OUTDOOR PROPAGATION PREDICTION AND MEASUREMENT POINT TO
POINT FOR WIRELESS LAN APPLICATION
NAJI ABDU EL.GADER AHMMED
UNIVERSITY TEKNOLOGI MALAYSIA
OUTDOOR PROPAGATION PREDICTOIN AND MEASUREMENTS POINT TO
POINT FOR WIRELESS LAN APPLICATION
NAJI. ABDU ELGADER AHMED
A dissertation submitted in fulfillment of the
requirements for the award of the degree of
Master of Engineering (Communication Engineering)
Faculty of Electrical Engineering
Universiti Technologi Malaysia
JUNE 2008
iii
To my beloved father and Mother
To my brothers and sisters
To my friends
iv
ACKNOWLEDGEMENT
In preparing this thesis, I was in contact with many people, researchers,
academicians, and practitioners. They have contributed towards my understanding and
thoughts. In particular, I wish to express my sincere appreciation to my dissertation
supervisor, Professor Dr. Tharek abd. Rahman, for his encouragement, guidance,
advices and motivation.
I would like to thank friends and staff in Wireless Communication Center
(WCC) for their help, facilities and for providing conducive working environment.
Besides, I am really thankful to Dr. Razwan from Civil Engineering (Land
Surveying Department) for all his efforts.
Finally, I am deeply and forever indebted to my parents, brothers and sisters for
their love, spiritual support and encouragement throughout my entire life.
v
ABSTRACT
Wireless Local Area Networks (WLANs) have emerged as a powerful
architecture capable of supporting the requirements of broadband wireless
communications. In this project, an outdoor propagation prediction is made for a pointto point microwave link (bridging) at Kolej KRP Universiti Teknologi Malaysia (UTM),
Johor, Malaysia. The link operates at frequency 5.8 GHz based on IEEE 802.11a
standard, the antenna gains was 17 dBi for both transmitter and receiver. The transmitted
power was 18 dBm. The measurement of the signal strength was carried out in the site
where the link stands. The transmitter antenna mounted on the top of the fellow
office
, while the receiver distance 113m, at the building
. A simulation of the
same microwave link was carried out using a site specific propagation prediction tool
provided by Site Ware Technologies. The simulation tool is a three-dimensional (3-D)
ray tracing code employing modified shoot and bounce ray (SBR) method know as the
Vertical Plane Launch (VPL). Then that presented simulation result into three
dimensional using Matlab software. The result From VPL simulation is a path loss about
-54 dB, the delay spread equal to 0.068 ns. The measured signal strength on the field
was -64 dBm which is less than the predicted from the simulation by 28 dB. Due to
many factors influencing the simulation like the data base accuracy, system errors the
which they led the differences between the measured and predicted signal strength.
vi
ABSTRAK
Rangkaian Kawasan Tempatan Tanpa Wayar (WLAN) telah menjadi sesuatu alat
yang berkuasa untuk menyokong keperluan komunikasi tanpa wayar berjalur lebar.
Didalam projek ini, anggaran Perambatan luaran titik-ke-titik jaluran gelombang mikro
sebagai penyambung di Kolej Rahman Putra (KRP), Universiti Teknologi Malaysia.
Jaluran itu beroperasi di frekuensi 5.8 GHz berasaskan piawaian IEEE 802.11a, antenna
adalah 17 dBi bagi kedua-dua transmitter dan penerimanya. Kuasa yang dipancarkan
adalah 18 dBm. Pengiraan kekuatan signal dilakukan di tapak dimana jaluran didirikan.
Pemancar tersebut dipasang pada atap bangunan pejabat KRP,
penerimanya terletak pada jarak 113m di bangunan
manakala
. Simulasi gelombang mikro
yang sama telah dilaksanakan melalui alat yang disediakan oleh Site Ware
Technologies. Alat simulasi ini adalah 3-dimensi (3-D) penjejak kod menggunakan
ubahsuaian ‘shoot and bounce ray’ (SBR) yang dikenali sebagai ‘Vertical Plane Launch’
(VPL). Simulasi itu diterjemahkan dalam 3-dimensi menggunakan perisian Matlab.
Keputusan simulasi VPL menunjukkan kehilangan signal sebanyak -54 dB, ‘delay
spread’ adalah bersamaan dengan 0.068 ns. Signal yang diukur adalah -64 dBm, kurang
daripada anggaran simualsi iaitu 28dB. Oleh kerana banyak faktor mempengaruhi
simulasi seperti ketepatan pangkalan data, ralat system menyebabkan perbezaan diantara
nilai yang diukur dan nilai anggaran kekuatan signal.
vii
LIST OF CONTENTS
CHAPTER
1
TITLE
PAGE
DECLARATION
ii
DEDICATION
iii
ACKNOWLEDGEMENT
iv
ABSTRACT
v
ABSTRAK
vi
TABLE OF CONTENTS
vii
LIST OF TABLES
xi
LIST OF FIGURES
xii
LIST OF SYMBOLS
xiv
LIST OF APPENDICES
xvii
INTRODUCTION
1
1.1
Introduction
1
1.2
Development of wireless technology
2
1.3
Problem statement
4
1.4
Objective
5
1.5
Scope of Project
5
1.6
Project methodology
6
1.6.1 Suite Survey and Topographical Map Building
6
viii
1.6.2
1.7
2
Data Collection of Terrain and Buildings
7
1.6.3 VPL Simulation.
8
1.6.4
8
Real time measurements
Organization of the Thesis
10
PROPAGATION AND CHANNEL MODELING
11
2.1
Introduction
11
2.2
Free Space Propagation
12
2.3
Basic Propagation Mechanisms
14
2.3.1
Reflection
15
2.3.1.1 Reflection from Dielectrics
15
2.3.1.2 Brewster Angle
16
2.3.1.3 Reflection from Perfect Conductors
17
2.3.1.4 Ground Reflection (Two-Ray) Model
17
2.3.1.5 Diffraction
19
2.3.1.6 Fresnel Zone Geometry
19
2.3.1.7 Scattering
21
2.4
Multipath Fading
21
2.5
Importance of Propagation Prediction
23
2.5.1
Challenges to the Propagation Modeling
24
2.5.2
Empirical, Theoretical, and Site-Specific Models
25
2.5.2.1 Okumura Model and Hata Model
26
2.5.2.2 Over-Rooftop Models
27
2.6
Ray Tracing Models
28
2.6.1
Shooting-and-Bouncing ray (SBR) launching algorithm 28
2.6.2
Image Method and Hybrid Method
30
2.6.3
Acceleration of Ray-Tracing Algorithms
31
2.6.4
Accuracy of Ray-Tracing
34
2.6.5
Conclusion
34
ix
3
4
Broad Band Channel Characteristics
35
3.1
Wireless LAN and IEEE 802.11a/g
35
3.2
Broadband Radio Channel Characteristics
37
3.2.1
Envelope Fading
38
3.2.2
Time Dispersive Channel
38
3.2.3
Frequency Dispersive Channel
40
3.2.4
Summary
41
RAY TRACING PROPAGATION PREDICTION
42
4.1
Introduction
42
4.2
Site Survey
43
4.3
Introduction to VPL Tool
43
4.4
Algorithm of Simulation Software
44
4.5
Data for Simulation
46
4.5.1
Building Database
46
4.5.2
Receiver Database
47
4.5.3
Terrain Elevation Database
47
4.5.4 Antenna Radiation Pattern Database
48
4.6
Simulation Command Input
50
4.7
Output of the Prediction Tool
50
4.7.1
Power and Delay Spread Output
52
4.7.2
Impulse Response Output
52
4.7.3
Ray Path Information Output
53
4.8
Result Visualization
55
4.9
Summary
57
x
5
TEST BED OF WIRELESS CAMPUS
58
5.1
Introduction
58
5.2
Setting up the MikroTik RouterOSTM …
.60
5.2.1 Logging into the MikroTik Router
61
5.2.2 Adding Software Packages
62
5.2.3
62
5.3
6
7
Software Licensing Issues
Navigating Terminal Console
62
5.3.1 Web Browser and WinBox Console
63
5.4
Configuration of MikroTik PC Router
64
5.5.
DHCP Client and Server
65
5.6
Summary
66
RESULT AND ANALYSIS
67
6.1
Overview
67
6.2
Measurement Result
67
6.3
VPL Result and Analysis
69
6.4
Comparison between Prediction and Measurement Result
73
CONCLUSION AND FUTURE WORK
75
7.1
Conclusion
75
7.2
Future Work
76
REFERENCES
Appendices A – C
77
xi
LIST OF TABLES
TABLE NO.
TITLE
PAGE
3.1
802.11a/g modem parameters
36
4.1
Command Input Simulation
51
6.1
signal strength in different data rates
68
xii
LIST OF FIGURES
FIGURE NO.
TITLE
PAGE
1.1
Boundary Limits
7
1.2
Flow chart of the methodology
9
2.1
Propagation mechanisms
14
2.2
Reflection coefficient between two dielectric
16
2.3
Two-ray ground reflection model
17
2.4
Fresnel zones
20
2.5
Ray launching procedure
28
2.6
Ray cone and ray tube
29
2.7
Illustration of image method
30
2.8
Schematic illustration of the ray-launching procedure in the VPL
33
3.1
Maximum emission in the UNII band
36
3.2
A time dispersive (frequency-selective) channel
39
3.3
A frequency dispersive (time selective) channel
40
4.1
Flow Chart of VPL Program
45
4.2
Terrain visualization
49
4.3
Receiver visualization
49
4.4
Radiation pattern in polar-logarithmic
49
4.5
Power and delay Spread Output
53
4.6
Impulse Response Output
54
4.7
Ray Path Information Output
54
4.8
VPL Output Visualization Using Math lap
55
4.9
Ray visualization in(Y, X, Z) Coordinates from front Angle
56
xiii
4.10
Ray visualization in(X, Y, Z) Coordinates from side Angle
56
5.1
Wireless campus test bed system.
58
5.2
Download and installation process of MikroTik RouterOSTM
60
5.3
WinBox Console
64
5.4
Network Setting for MikroTik PC Router
64
5.5
Setting of MikroTik PC router in WinBox
65
5.6
Network of the test bed of wireless campus
66
6.1
Measurement result
69
6.2
Prediction result
70
6.3
Ray visualization
71
6.4
Prediction result impulse response output
72
6.5
Prediction result delay spread output
72
6.6
Result Ray Path
73
xiv
LIST OF SYMBOLS
CAD
-
computer aided design
UNII
-
unlicensed-national information infrastructure
BW
-
Band width
Rms
-
Root mean square
QoS
-
Quality of service
QAM
-
Quadrate amplitude modulation
QPSK
-
Quadrate phase shift keying
BPSK
-
Binary phase shift keying
mW
-
mili Watt
PHY
-
physical
GTD
-
Geometrical theory of Diffraction
UTD
-
Uniform theory of Diffraction
FDTD
-
Finite difference time domain
2-D
-
Two Dimension
3-D
-
Three Dimension
LOS
-
Line of sight
DEM
-
Digital Elevation Model
PC’S
-
Computers
AO
-
Paper size
IP
-
Internet Protocol
MIMO
-
Multiple input multiple outputs
CDMA
-
Code division multiple access
W-CDMA
-
Wideband CDMA
IMT
-
International Mobile Telecommunications
xv
4G
-
fourth-generation wireless communications
PDC
-
Personal Digital Cellular
3G
-
The third generations of wireless communications
2G
-
the second-generation digital cellular systems
GSM
-
Global System for Mobile Communications
AMPS
-
Advanced Mobile Phone System
NMT
-
Nordic Mobile Telephone
FM
-
Frequency Modulation
RF
-
Radio Frequency
WLAN
-
wireless local area networks
FCC
-
Federal Communication Commission
IEEE
-
Institute of Electrical and Electronic Engineering
VPL
-
Vertical Plane Launch
LOS
-
Line of sight
OFDM
-
Orthogonal frequency division multiplexing
DSSS
-
Direct sequence spread spectrum
Pt
-
Transmitting power
Pr
-
Receiving power
-
Transmitter antenna gain
-
Receiver antenna gain
-
Effective aperture of antenna
λ
-
Wavelength
C
-
Velocity of light
dB
-
Decibels
θ
-
Incidence angle
f
-
Frequency
ht
-
High of receiver antenna
hr
-
High of transmitter antenna
d1
-
Distance from transmitter to obstacle
d2
-
Distance from transmitter to obstacle
τ
-
Delay spread
xvi
L
-
Path loss
D
-
Distance
τn
-
Arrival time
xvii
LIST OF APPENDICES
APPENDIX
TITLE
A
Ray Tracing Propagation Prediction
A.1
Simulation Command Input
A.2
Database for simulation
A.2.1
Building Database (Part of BLD0.txt)
A 2.2
Receiver Database
A.2.3
Terrain Elevation Database (Part of te.txt)
A.2.4
Antenna Radiation Pattern Database (Part of rd.txt)
A.3 A.4
B Output of the Prediction Tool
VPL Ray Tracing Visualization Code
Test of Wireless System
B.1
Configuration of MikroTik PC Router
B.2
Configuration of MikroTik Radio Unit #1
C Topographical Maps
C.1
UTM Map with Contour Lines Illustrated
C.2
UTM Contour map Creating Illustration
C.3
UTM Contour map combined with the Original image
C.4
The UTM Topographical Image
CHAPTER 1
INTRODUCTION
1.1
Introduction
With the success of wired local area networks (LANs), the local computing
market is moving toward wireless LAN (WLAN) with the same speed of current wired
LAN. WLANs are flexible data communication systems that can be used for
applications in which mobility is required. In the indoor business environment, although
mobility is not an absolute requirement, WLANs provide more flexibility than that
achieved by the wired LAN. WLANs are designed to operate in industrial, scientific,
and medical (ISM) radio bands and unlicensed-national information infrastructure (UNII) bands.
In the United States, the Federal Communications Commission (FCC) regulates
radio transmissions; however, the FCC does not require the end-user to buy a license to
use the ISM or UNII bands. Currently, WLANs can provide data rates up to 11 Mbps,
but the industry is making a move toward high-speed WLANs.
Manufacturers are developing WLANs to provide data rates up to 54 Mbps or
higher. High speed makes WLANs a promising technology for the future data
communications market [1].
2
The need of an effective mechanism to evaluate radio propagation outside
buildings is increasing. It is also critical when we are going to decide where to place the
base station in order to give us the best performance.
Outdoor propagation is strongly influenced by specific features like the terrain
profile which may vary from a simple curved earth profile to highly mountains profile,
the construction materials, and the building structure. Due to reflection, diffraction, and
refraction of radio waves by objects the signal reaches the receiver from many paths and
this causes the multipath fading.
1.2
Development of Wireless Technology
In early 1864 Maxwell comes up with Maxwell equation by unifying the works
of Lorentz, Faraday, Ampere and Gauss. He predicted the propagation of
electromagnetic waves in free space at the speed of light. He postulated that light was an
electromagnetic phenomenon of a particular wavelength and predicted that radiation
would occur at other wavelengths as well [2].
His theory was not well accepted until 20 years later, after Hertz validated the
electromagnetic wave (wireless) propagation. Hertz demonstrated radio frequency (RF)
generation, propagation, and reception in the laboratory. His radio system experiment
consisted of an end-loaded dipole transmitter and a resonant square-loop antenna
receiver operating at a wavelength of 4 m. For this work, Hertz is known as the father of
radio, and frequency is described in units of hertz (Hz) [2]. Hertz's work remained a
laboratory curiosity for almost two decades, until a young Italian, Guglielmo Marconi,
envisioned
a
commercialized
method
the
for
use
of
transmitting
and
electromagnetic
receiving
wave
information.
propagation
for
Marconi
wireless
communications and allowed the transfer of information from one continent to another
without a physical connection.
3
The telegraph became the means of fast communications. Distress signals from
the S.S. Titanic made a great impression on the public regarding the usefulness of
wireless communications. Marconi's wireless communications using the telegraph meant
that a ship was no longer isolated in the open seas and could have continuous contact to
report its positions. Marconi's efforts earned him the Nobel Prize in 1909.
World War II also created an urgent need for radar (standing for radio detection
and ranging). The acronym radar has since become a common term describing the use of
reflections from objects to detect and determine the distance to and relative speed of a
target. Radar’s resolution (i.e., the minimum object size that can be detected) is
proportional to wavelength. Therefore, shorter wavelengths or higher frequencies (i.e.,
microwave frequencies and above) are required to detect smaller objects such as fighter
aircraft.
Wireless communications using telegraphs, broadcasting, telephones, and pointto-point radio links were available before World War II. The widespread use of these
communication methods was accelerated during and after the war. For long-distance
wireless communications, relay systems or troposphere scattering were used. In 1959, J.
R. Pierce and R. Kompfner envisioned transoceanic communications by satellites [2].
This opened an era of global communications using satellites.
The satellite uses a broadband high-frequency system that can simultaneously
support thousands of telephone users, tens or hundreds of TV channels, and many data
links. The operating frequencies are in the gigahertz range. In the 1960s and 1970s, the
cellular concept was developed in Bell laboratories; the first generation of wireless
mobile communication system appeared in the 1980s and was based on analog
technology with FM modulation.
4
Examples of first-generation cellular sys-terms are the Nordic Mobile Telephone
(NMT) and Advanced Mobile Phone System (AMPS). In the early 1990s, the secondgeneration (2G) digital cellular systems were developed with varying standards [2].
Examples include the Group Special Mobile [(GSM), now Global System for
Mobile Communications)] in the U.K., IS-54/136 and IS-95 in the U.S., and the Personal
Digital Cellular (PDC) in Japan. In general, the 2G systems have improved spectral
efficiency and voice quality.
The third generations (3G) of wireless communications are currently being
installed in different regions of the world. The 3G systems provided multimedia services
and satisfy more requirements such as applications and communications “anytime and
anywhere” To this end, wide-band and broadband radio technologies will be necessary.
The examples of 3G standards are International Mobile Telecommunications 2000
(IMT-2000), CDMA-2000, and NTT DoCoMo W-CDMA systems.
The 4G system will provide an all-IP network that integrates several services
available at present and provides new ones, including broadcast, cellular, and cordless,
WLAN, and short-range communication systems. The general trend in the development
of wireless communication is the use of higher data rates (broader frequency band),
propagation in more complex environments, employment of smart antennas, and use of
multiple-input multiple-output (MIMO) systems [3].
1.3
Problem Statement
Wireless LAN have become widely spread on these day’s and by the fact that
wireless LAN can cover the places which they are quite difficult to access by wire line.
5
Due to the varying of the terrain profile from simple curved earth to highly
mountainous profile and the presence of trees, buildings, and other obstacles’ is that the
signal propagated from transmitter to receiver will experience many signal
transformation and paths and this will reduce the signal strength. This study is expected
to help in determining the accurate location of both the transmitter and receiver antennas
of the microwave link.
1.4
Objective
The main objective of this research is to predict and measure the path loss and delay
spread in a point to point microwave link at frequency 5.8 GHz, in order to obtain the
best link performance.
1.5
Scope of Project
The site related is located on kolej KRP inside Universiti Tekhnologi Malaysia
the transmitter placed on the top of ‫ܩ‬଴ଵ which is the fellow office and the receiver is on
‫ܩ‬଴ଶ which is one of the employer houses.
They are the locations over a terrain and in remote rural areas, this links are
already exist and this investigation will help in the future to predict for where to place a
link point to point bridging or long rang point to point microwave linking. The physical
model is to predict propagation effect in the related site by using ray tracing simulation
program based on vertical plane lunch (VPL) then the result visualized by math lab. The
empirical model represents by the path loss field measurements.
6
1.6
Project Methodology
1.6.1 Site Survey and Topographical Map Building
Site survey involved in locating the place which the plan will be held on and its
very important to see the actual specification of the field environment like terrain profile
the trees, buildings in-between the suggested link and is there any possibilities of lineof-sight.
The most difficulties lays on getting the Topographical Map normally for the
specified area which the work will held there are no such Digital Elevation Map ready to
use.
From a hard copy of topographical map size (AO) which scanned by special
scanner for these size of map the scanner was set to give us 200 dpi Pixel quality, the
result was JPG picture which its size 168 M Bytes, and this size is very heavy to normal
PC’s so the image compressed for more useful process and time accelerating, the picture
after a lot of compression reaches only 3 M Bytes.
After that map opened by AutoCAD by insert raster image and by land
surveying expert the map set to be on RSO WM Projection with scaling it to real scale as
it in the earth and rotate it to be on the true North. , then last step was to digitize the map
from raster mode to be on the vector mode now the Contour Map or Digital Elevation
Map ready for work. Appendix (C.4) shows the scanned AO size UTM map.
7
1.6.2 Data Collection of Terrain and Buildings
Firstly for the terrain data base the (DEM) of UTM is transformed to (X, Y, Z)
points by a powerful surveying under water licensed program called (Hydro Processing),
To get the terrain data base for the specified area, the original image matched with the
(.DEM) so as to specify the field which contain all the building included the ones which
the transmitter and receiver or placed on them, then by drawing a rectangular shape as
the boundary limits Fig (1.1) shows that.
Figure 1.1: Boundary Limits
After that the rectangular coordinate (X, Y) the maximum minimum taken to
software called (Surfer) to make a grid for the rectangular shape area with a suitable step
for the Y and X and lastly transform the grid to (X,Y,Z) matrix and this is what called
the (Terrain Data Base).
The Building Data Base is much easer respectively to the terrain, from the
combination of the DEM and the original scanned image the building has been drawn
and manually entered the heights, and then we can simply get the building data base. All
the data are transferred to an Ms Excel to organize them and on the last stage of all this
process save them as the text files to be accepted by the (VPL) Software.
8
1.6.3
VPL Simulation
Firstly selecting up the parameters for VPL like the number of reflections of the
rays from the objects which will considered, operating frequency, Antenna type which is
(directional antenna in our case), and simulation is carried out and the outcome of the
simulation is tested if no errors, the result can be plotted by the MATHLAP program. If
errors occur, then simulation must be repeated by changing either the parameters of the
VPL itself or the inputs text files.
1.6.4 Real time measurements
The measurements of the signal strength for the bridging link can be read directly
from the bridge which connected the receiver end. Once the real time measurement done
a comparison will be done with the predicted results, this results shows that the
prediction are efficient ant can be done at any similar environment to find the best places
where to place the transmitter and receiver for the microwave link.
.
9
¾
Site Survey
¾
Building Topographical Map
Data Collection Using Auto CAD
¾
Building data base
¾
Terrain data base
¾
Radiation pattern data
¾
Receiver data base
Collecting Parameters
No
Yes
VPL Simulation Success
Illustration by Mathlap
Real Measurements
Updating
Comparison
between Real measurements
Data base
and prediction
Done
Figure 1.2: Flow chart of the methodology
Result analysis
10
1.7
Organization of the Thesis
Chapter 1 contains the development of the wireless technology followed by the
problem statement, objective and scope of the project have been described and lastly the
flow chart of the work which have been carried.
Chapter 2 is all about literature review started from propagation mechanism such
as reflection, diffraction, multipath fading.
Talks about broadband channel characteristics held on Chapter 3, the starting
was from wireless LAN standard IEEE 80.2.11a/g brief discretion then switch to the
main broadband channel characteristics like envelope fading and dispersion.
Chapter 4 explains the whole propagation prediction steps starting from the site
survey followed by describing of the VPL software and their entire input databases
needed to complete the simulation, some examples are provided. The outputs of the
simulation software are briefly described. At the last some of the outcome result
visualized.
Chapter 5 talks about test bed of the wireless campus, through this operation tell
how the system construction with the all equipments in addition to system configuration
is made.
Chapter 6 contains the conducted results with analysis, and the comparison
between prediction and measurements. Chapter 7 is the final one and it’s a conclusion
and future work.
CHAPTER 2
PROPAGATION AND CHANNEL MODELING
2.1
Introduction
The transmission path between the receiver and transmitter can vary from
absolute line of sight to one that obstructed by buildings and any similar object. The
wired channel is easy to predict not like the wireless channel which are random and
difficult to analyze. Radio propagation models mostly focused on predicting the mean
signal strength which received from a given distance from the transmitter.
Mainly there are two types of propagation models, the first one is the
propagation model which characterize by the signal strength over large separation area
between the transmitter and the receiver and this called (large-scale propagation
models),secondly small-scale or fading models and they characterize by the rapid
fluctuation of the received signal over very short travel distance .
With accurate description of a given frequency band channel the designer of the
wireless system can predict the signal coverage and possible data rate. Channel models
are used to determine the optimum places for antenna installation and also to analyze the
interference between different systems.
12 2.2
Free Space Propagation:
Free space transmission is a primary consideration in essentially all wireless
communication system. In this case of line of sight (LOS) propagation, there are no
obstructions due to earth’s surface or other obstacles. The free space model predicts that
received power decays as a function of the transmitter-receiver separation distance
raised to some power. The free space received by a receiver antenna which separated
from a radiating transmitter antenna by a distance d, is given by the Friis free space
equation below:
(d) =
: is the transmit power,
(2.1)
(d): is the receive power which is function of the transmitter
–receiver separation.
: is the transmit antenna gain,
: is the receive antenna gain, d: is the transmit-
receive separation distance in meters, L: is the system loss factor not related to
propagation (L
1), when L=1 no hardware loss. The wavelength in meters is λ [4].
The gain of an antenna is related to its effective aperture
given by the equation
(2.2).
G=
2
(2.2)
An isotropic antenna is an ideal antenna which radiates power with unit gain
uniformly in all directions, and is often used to reference antenna gains in wireless
systems. The effective isotropic radiated power (EIRP) is defined as:
EIRP =
(2.3)
In practice unit of antenna gains is given as dBi (dB gain with respect to an
isotropic antenna).
13 The path loss which represents signal attenuation as positive quantity measured
in dB, is defined as the difference in dB between the effective transmit-receive power,
the path loss of the free space given by equation (2.4)
Path loss (dB) = 10
= 10
(2.4)
The Friis free space model only valid predictor for Pr for values of d which are in
the far-field of the transmit antenna. Fraunhofer region is defined as the region beyond
the far-field distance df which is related to the largest linear dimension of the transmit
antenna aperture and the carrier wavelength the Fraunhofer distance given is by the
equation below:
=
(2.5)
Where D is largest physical linear dimension of the antenna. Additionally to be
in the far field region,
must satisfy:
>> D
>> λ
Further more, it is clear that the Friis equation does not hold for d = 0. For this
reason large-scale propagation models use a close in-distance d0 as a known received
power reference point
(d) =
(d0)
The receive power
value of
(
d>
>
(d) at any distance d>
(2.6)
may be related to
at
.The
) may be predicted from equation (2.1) or may be measured in the radio
environment by taking the average received power at many points located at close inradial distance
from the transmitter [4].
14 2.3
Basic Propagation Mechanisms:
There are three main propagation mechanisms used with the propagation which
are the diffraction, reflection and scattering, the following paragraphs explain more these
mechanisms.
Diffraction occurs when radio path between the transmitter and receiver is
obstructed by surface that has sharp irregularities (edge), the secondary wave resulting
from obstructing surface are present throughout the space and even behind the obstacle,
even when a line-of-sight path does not exist between transmitter and receiver. At high
frequencies, diffraction, like reflection, depends on the geometry of the object, as well as
the amplitude, face a polarization of incident wave at the point of diffraction.
Reflection occurs when propagation of electromagnetic wave impinges upon an
object which has very large dimensions when compared to the wavelength of the
propagation wave.
Scattering occurs when the medium through which the wave travels consists of
objects with dimension that are small compared to the wavelength, and where the
number of obstacles per unit volume is large. Scattered waves are produced by rough
surface, small objects, or by irregularities in the channel. Fig 2.1 shows the propagation
mechanisms.
Figure 2.1: Propagation mechanisms
15 2.3.1
Reflection
When a radio wave propagating in one medium upon another medium having
different electrical properties, the wave is partially transmitted. If the plane wave is
incident on perfect dielectric, part of the energy is transmitted the second medium and
part of the energy is reflected back into the first medium, and there is no loss of energy
in absorption. If the second medium is a perfect conductor, then all incident energy is
reflected back into the first medium without loss of energy. The electric field intensity of
the reflected and transmitted waves may be related to the incident wave in the medium
of origin through the Fresnel reflection coefficient (Γ). The reflection coefficient is a
function of material properties, and generally depends on the polarization, angle of
incident, and frequency of the preparative wave.
2.3.1.1 Reflection from Dielectrics
Figure 2.2 shows an electromagnetic wave incident at an angle
i
with the plane
of the boundary between two dielectric media. The plane of incident is defined as the
plane containing the incident, reflected, and transmitted rays. The reflection coefficient
for the two cases of parallel and perpendicular E-field polarization at the boundary of
two dielectrics is given the equations:
Where
Γ =
=
Γ =
=
is the intrinsic impedance of the
(E- field in place of incidence)
(2.6)
(E- field not in plane of incidence) (2.7) medium, and is given by
the permittivity and permeability respectively.
, , represent
16 Figure 2.2: Reflection coefficients between two dielectric [4].
2.3.1.2 Brewster Angle
The Brewster angle is the angle at which no reflection occurs in the medium of
origin. It occurs when the incident angle θ B is such that the reflection coefficient Γ is
equal to zero. The Brewster angle is given by the value of θ B, which satisfies the
equation (2.7) [4].
Sin ( θ B) =
(2.8)
For case when the first medium has a relative permittivity
Sin ( θ B) =
can be expressed as:
(2.9)
Note that the Brewster angle occurs only for vertical (parallel) polarization
17 2.3.1.3 Reflection from Perfect Conductors Since electromagnetic energy cannot pass thought a perfect conductor a plane
wave incident on a conductor has all of its energy reflected. As the electric field at the
surface of the conductor must be equal to zero at all times in order to obey Maxwell’s
equations. The reflected wave must be equal in magnitude to the incident wave [4].
For the case when E-field polarization in the plane of incidence:
=
(E-field in the plane of incidence)
For the case when the E-field is not horizontally polarized:
=
(E-field normal to plane of incidence)
2.3.1.4 Ground Reflection (Two-Ray) Model
In the radio channels a single direct path between the transmitter and the receiver
is seldom the only physical means for propagation, and hence the free space propagation
model is in most cases inaccurate when used alone[4]. The two-ray ground reflection
model which shown in Fig 2.4 is a useful propagation that is based on geometric optics,
and consider both the direct path and ground reflected propagation path between
transmitter and receiver. This model has been found to be reasonably accurate for
predicting the large-scale strength over distances of several kilometers radio systems.
Figure 2.3: Two-ray ground reflection model [4]
18 In most communication systems, the maximum transmitter-receiver separation
distance is at most only a few ten of kilometers, and the earth may be assumed to be flat.
The total received E-field, E
TOT,
is then result of direct line- of sight component, E LOS
and the ground reflected component, E.g..
If E0 is the free space E-field (in units V/m) at a reference distance d0 from the
transmitter, then for d > d0, the received E-field can be approximated as:
=
λ
(d) =
(2.10)
(2.11)
The received power at a distance d from the transmitter for the two-ray ground
bounce model can be expressed as:
=
As seen from equation (2.12) at large distances (d
(2.12)
), the received power
falls off with distance raised to the forth power. This is a much more rapid path loss than
is experienced in free space. Note also that at large values of d the received power and
path loss become independent of frequency [4].
19
2.3.1.5 Diffraction
Diffraction allows radio signals to propagate around the curved surface of the
earth, beyond the horizon, and to propagate behind obstruction. Although the received
field strength decreases rapidly as the receiver moves deeper into the obstructed
(shadowed) region, the diffraction field still exists and often has sufficient strength to
produce a useful signal.
The phenomenon of diffraction can be explained by Huygen’s principle, which
states that all points on a wavefront can be considered as point source for the production
of secondary wavelets combine to produce a new wavefront in the direction of
propagation.
Diffraction caused by the propagation of secondary wavelets into a shadowed
region. The field strength of a diffracted wave in the shadowed region is the vector sum
of the electric field components of all secondary wavelets in the space around the
obstacles.
2.3.1.6 Fresnel Zone Geometry
Fresnel zones explain the concept of diffraction loss as a function of the path
difference around the obstruction. Fresnel zone represent successive region where
secondary waves have a path length from the transmitter to receiver, which are n λ
greater than the total path length of a line-of-sight path. Figure 2.4 demonstrate a
transparent plane located between a transmitter and receiver. The concentric circles on
the plane represent the loci of the origins of λ of successive circles. These circles called
Fresnel zones. The successive Fresnel zones have the effect of alternately providing
constructive and destructive interference to the total received signal [4].
20
Figure 2.4: Fresnel zones [4]
The radios of the nth Fresnel zone circle is denoted by r n and can be expressed in
terms of n,
=
,
and λ .
for
(2.13)
The excess total path length traversed by a ray passing through each circle is
n λ where n is an integer. The total half that for 1st zone alone. Loss small if 1st zone is
unobstructed. Half intensity (-6dB) if half the wavefront obstructed. The Fresnel zone of
figure 2.4 will have maximum radii if the plane is midway between the transmitters and
receiver, and the radii become smaller when the plane is moved towards either the
transmitter or receiver. This effect illustrates how shadowing is sensitive to the
frequency as well as the location of the obstruction [4]
21
2.3.1.7 Scattering
The actual received signal in radio environment is often stronger than what is
predicted by reflection and diffraction models alone and this because of when a radio
wave impinges on a rough surface, the reflected energy is spread out (diffused) in all
directions due to scattering. Objects such as lampposts and trees tend to scatter energy in
all directions, thereby providing additional radio energy at a receiver.
Flat surfaces that have larger dimension than a wavelength may be modeled as
reflective surface. However, the roughness of such surface often induces propagation
effects different from the seculars reflection. Surface roughness is often tested using
Rayleigh criterion that defines as a critical high (hc) of surface protuberance for a given
angle of incidence
, given by [4]:
=
λ
(2.14)
A surface is considered smooth its minimum to maximum protuberance h is less
than h r and is considered rough if the protuberance is greater than
. For
rough surfaces,
the flat surface reflection coefficient needs to be multiplied by a scattering loss factor ρ s
to account for the dimensioned reflected field
2.4
Multipath Fading
In most radio channels, the transmitted signal arrives at the receiver from various
directions over a multiplicity of paths. The phase and amplitude of a signal arriving on
each different path are related to the path length and conditions of the path. Solving the
Maxwell’s equations with boundary conditions representing the physical properties and
architecture of the environment can do an exact analysis of the multipath propagation.
22
Unfortunately, this method is computationally burdensome, and even with today’s most
sophisticated computers, only the simplest structures can be treated.
Hence, in order to be able to assess the performance capabilities of various
wireless systems, root mean square (rms) delay spread is a good measure to grossly
quantify the different multipath channels. The equation for rms delay spread (σ) [5] used
is
=
(2.15)
With mean excess delay ( )
=
∑
=
(2.16)
∑
∑
∑
(2.17)
Where P ( ) is the relative amplitudes of the multipath components and
is the
time delay during multipath energy falls.
In general, the channel gain can be decomposed into a path loss with large-scale
(long-term) shadowing components and small-scale (short-term) fading components.
The path loss represents the local mean of the channel gain and is therefore dependent
on the distance between the transmitter and receiver and on the propagation
environment. The short-term fading is due to multipath propagation and is in
independent of the distance between the transmitter–receiver. Rayleigh or Rician
distribution can characterize the short-term fading. The fading is due to unknown local
changes in the propagation environment such as people moving around the room,
passing vehicles.
23
For channel with dominant signal component present the effect of the dominant
signal arriving with weaker multipath signal gives rise to Rician distribution, we have
parameter K that is defined as the ratio between the deterministic signal power and the
variance of the multipath the equation below explain that.
K (dB) = 10 l
A
dB
(2.18)
Where:
A
= peak amplitude of dominant signal
= standard deviation of the local power
As the dominant signal becomes weaker (A
0, K
∞), the Rician
distribution degenerates to Rayleigh distribution. Raleigh distribution is the most
commonly used for multipath fading where all signals suffer neatly same attenuation,
but arrive with different phases [5].
2.5
Importance of Propagation Prediction
Before
implementing
designs
and
confirming
planning
of
wireless
communication systems, accurate propagation characteristics of the environment should
be known. Propagation prediction usually provides two types of parameters
corresponding to the large-scale path loss and small-scale fading statistics. The path-loss
information is vital for the determination of coverage of a base-station (BS) placement
and in optimizing it. The small-scale parameters usually provide statistical information
on local field variations and this, in turn, leads to the calculation of important parameters
that help improve receiver (Rx) designs and combat the multipath fading. Without
propagation predictions, these parameter estimations can only be obtained by field
measurements which are time consuming and expensive. The following subsections
provide a brief description of deterministic models, statistical models, and challenges
facing the development of accurate and sufficiently propagation prediction models.
24
2.5.1 Challenges to the Propagation Modeling
Wireless communication channels are inherently frequency dispersive, time
varying, and space selective, although only one or two of these dependencies will appear
in some cases. The fast evolution of wireless communications has lead to the use of
higher frequency bands, smaller cell sizes, and smart antenna systems, making the
propagation prediction issues more challenging.
In macrocells, since the transmitting antenna is usually located on a high tower,
simple empirical and statistical models are widely used with satisfactory accuracy. As
for the micro-cells and especially for picocells, the height of the transmitting antenna
may be lower than the average height of the buildings in the regions involved. In this
case, the geometry of the buildings and terrains will greatly affect the propagation of the
radio waves, causing wide shadow regions. The outdoor radio wave propagates through
reflections from vertical walls and ground, diffractions from vertical and horizontal
edges of buildings, and scattering from non-smooth surfaces, and all possible combinations. There is no general empirical and statistical model that can be used for prediction
of these complicated propagation environments.
Smart antenna systems exploiting space diversity require information on the
angle of arrival of the multipath in addition to the usual parameters such as path loss and
delay spread. A MIMO system uses the multipath to provide higher capacity completely
different from the classical systems where multipath is considered harmful. All these
new systems involve space-time and space-frequency channel models.
To deal with the new complex propagation environments, site-specific models
have been developed based on ray-tracing techniques. In a basic ray-tracing algorithm,
the main task is to determine the trajectory of a ray launched from a transmitting
antenna. This procedure involves the calculation of the intersection of a ray with a
surface (in three-dimensional (3-D) cases) or a ray with an edge segment (in twodimensional (2-D) cases). The computation time might be huge or even beyond the
capability of present computers if the propagation environment is large and/or complex.
25
The computation efficiency is then the biggest obstacle against the application of raytracing methods. An efficient ray-tracing procedure is also important for improving the
prediction accuracy since more types of rays such as reflected, transmitted, diffracted
and scattered rays and their combinations can be taken into account.
The accuracy of propagation prediction involves many aspects. These include the
accuracy of locations and sizes of buildings and accurate knowledge of the electric
parameters of walls and other objects involved. Trees, large posts, traffic, and
pedestrians in outdoor cases and furniture in indoor cases can also influence the results
and make a difference. Recently, accurate characterization of complex wall structures
including metal-framed windows is receiving attention due to the requirement of a more
accurate prediction of the indoor/outdoor propagation mechanism. To meet these
challenges, existing prediction methods should be modified and improved, and new
procedures and techniques have to be developed [3].
2.5.2
Empirical, Theoretical, and Site-Specific Models
The path-loss prediction models can be roughly divided into three types, as the
empirical, theoretical, and site-specific models. Empirical models are usually a set of
equations derived from extensive field measurements.
Empirical models are simple and efficient to use. They are accurate for
environments with the same characteristics as those where the measurements were
made. The input parameters for the empirical models are usually qualitative and not very
specific, for example a dense urban area, a rural area, and so on. One of the main
drawbacks of empirical models is that they cannot be used for different environments
without modification, and sometimes they are simply useless. For example, the
empirical model for macrocells cannot be used for indoor picocells. The output
parameters are basically range specific, not site specific.
26
Site-specific models are based on numerical methods such as the ray-tracing
method and the finite-difference time-domain (FDTD) method. The input parameters
can be very detailed and accurate. The disadvantages of the site-specific methods are the
large computational overhead that may be prohibitive for some complex environments.
Theoretical models are derived physically assuming some ideal conditions. For example,
the over-rooftop diffraction model is derived using physical optics assuming uniform
heights and spacing of buildings. Theoretical models are more efficient than the sitespecific models and more site-specific than the empirical models.
2.5.2 .1 Okumura Model and Hata Model
The Okumura model is an empirical model based on extensive measurements
made in Japan at several frequencies in the range from 150 to1920 MHz (it is also
extrapolated up to 3000 MHz)[3]. Okumura’s model is developed for macrocells with
cell diameters from 1 to 100 km. The heights of the BS antenna are between 30–1000 m.
The Okumura model takes into account some of the propagation parameters such as the
type of environment and the terrain irregularity. The basic prediction formula is as
follows:
(dB) =
Where
+
(f, d) – G (
)-G(
)-
(2.19)
(dB) is the median value of the propagation path loss.
is the free space path loss, and can be calculated using equation (2.4).
is the medium attenuation value relative free space in an urban area .
G(
) and G (
) are the height gain factors of BS and mobile antennas.
is correction factor due to an environment.
and
measurements. G (
are determined by looking up curves derived from
) and G (
) are calculated using simple formulas.
27
Terrain information can be qualitatively included in the Okumura model. For
example, the propagation environments are categorized as open area, quasi-open area,
and suburban area. Other information such as terrain modulation height and average
slope of terrain can also be included.
The Hata model [6] is a formula-based Okumura model (graphics-based) and can
be used more effectively. The frequencies range from 150 to 1500 MHz. It has been
extended to cover the frequency band from 1500 to 2000 MHz [7].
2.5.2 .2 Over-Rooftop Models
Over-rooftop models are typical theoretical models [8], [9] that are more precise
than the Okumura model for the description of the urban environments. Based on the
physical optics and some assumptions made for the geometry of the buildings and
heights of BS antennas, formulas are derived that give the average received signal for
mobiles at street level. Typical assumptions are that the heights of the buildings are
equal and the spacing between the buildings is identical.
In over-rooftop models, the path loss in decibels is the sum of free-space loss and
the so-called excess loss (
+
). The excess loss is further divided into two parts
=
. for example the diffraction of the fields at the rooftop before the mobile
down to the street level, and the reduction of the field at this rooftop as a result of
propagation over the previous rows of buildings.
28
2.6
Ray Tracing Models
Ray theory emerged as a highly promising procedure for providing an accurate
site-specific means to obtain useful simulation results [10], [11], [12], [13]. It should be
noted that the ray-tracing method also serves as a starting point for statistical modeling.
According to the ray optics and the uniform theory of diffraction (UTD), propagation
mechanisms may include direct (LOS), reflected, transmitted, diffracted, scattered, and
some combined rays, which in fact complicates and in many realistic propagation
environments, slows down the calculation procedure. Finally A ray tracing is a
technique that incorporates site-specific environmental data.
2.6.1 Shooting-and-Bouncing Ray (SBR) Launching Algorithm
The basic procedure of a ray-tracing method is the SBR algorithm [14]. First, a
ray is launched from the transmitting antenna (Tx), then the ray is traced to see if it hits
any object or is received by the receiving antenna. When an object is hit, reflection,
transmission, diffraction, or scattering will occur, depending on the geometry and the
electric properties of the object. When a ray is received by a receiving antenna, the
electric field (power) associated with the ray is calculated. A schematic of the SBR
method is shown in Fig 2.5.
Figure 2.5: Ray launching procedure.
This algorithm has some fundamental issues that need to be considered. The first
is how to launch a ray. The second is how to determine if a ray hits an object.
29
Third, if there are several possible objects that can be hit by the ray, how is it
determined which one is really hit? The fourth is how to determine whether a ray is
received. In the following, ray launching and reception criteria as well as ray intersection
with an object will be reviewed:
1- Ray Launching Model and Reception Criteria
A ray is actually a ray tube and is usually a cone, as shown in the Figure below
(a)
(b)
Figure.2.6: Ray cone and ray tube. (a) Ray cone. (b) Ray tube.
When ray cones are used to cover the spherical wavefront at the receiving
location, these cones have to overlap [10]. When ray tubes [see Fig 2.6 (b)] are used, the
spherical wavefront can be covered without the overlapping of ray tubes
To determine whether a ray is received or not by a receiving antenna, one has to
check if the receiving point is inside the ray cone or tube. If yes, the ray will be received;
otherwise, it will not. For the ray-cone scheme, the reception test can be easily carried
out by using a reception sphere centered at the receiving point with radius equal to
√
[10] Where
angle between two adjacent rays and d is is total length of the ray
2- Intersection Test of a Ray with an Object
To determine if a ray hits an object, one has to test the intersection of a ray with
the object. This is a classic problem in computational geometry and graphics [15]. A
naive SBR method tests all the objects to determine whether a ray hits an object. When
the number of objects is large, the testing can be very time consuming and inefficient.
30
2.6.2 Image Method and Hybrid Method
The image method is a simple and accurate method for determining the ray
trajectory between the transmitter (Tx) and Rx. Fig. (2.7) shows the basic idea of the
image method. For this simple case, the image of Tx due to W1 is first determined (Tx1
in Fig 2.7. Then the image Tx1 due to W2 is calculated (Tx2). Connected Rx and Tx2,
one can find a reflection point (P2) on W2. Another reflection point (P1) is the
intersection point of W1 with line connecting P2 and Tx1 [3].
The image method is accurate, but suffers from inefficiency when the number of
walls involved is large and reflection times are high. For realistic applications, special
techniques such as the hybrid and acceleration methods have to be used to reduce the
computation time.
Figure 2.7: Illustration of image method [3]
Tan et al. [16] proposed a hybrid method combining the image and SBR
methods. The SBR method is used to quickly identify a possible ray trajectory from
transmitter to receiver. When the trajectory is found, a series of walls involved can be
determined.The exact reflection positions can then be accurately found by the image
method. This method has the advantages of the SBR (efficient) and image (accurate)
methods.
31
2.6.3
Acceleration of Ray-Tracing Algorithms
The ray-tracing method is simple and is most widely used in the area of site-
specific propagation prediction. However, the ray-tracing method can be very
computationally inefficient. This is why there are many publications focusing on the
acceleration of the ray-tracing algorithms. There are several ways to achieve the
acceleration. The first is to reduce the number of objects on which actual ray-object
intersection will be performed. The second is to accelerate the calculation of the
intersection test. All acceleration methods concern the preprocessing of the propagation
environments and/or the positions of Tx and/or Rx. In this section, we will provide a
brief summary of these efforts.
1) Angular Z-Buffer (AZB): [17], [18]: This method is based on the light
buffer technique used in computer graphics. The basic idea is to divide the space into
angular regions according to a source point. The source point can be a Tx or an image of
it related to a reflection plane. When a ray is launched from the source point, only those
objects located in the angular region containing the ray need to be tested for ray
intersection. This method can accelerate the ray-tracing algorithm, but, when multiple
reflections are needed, the preprocessing is not easy. This is because there are many
source points (including the Tx and a large number of its images) and an AZB should be
established for each of them.
2) Ray-Path Search Algorithm: Based on the idea that ray-tracing routines
should be applied only to those areas where rays are likely to exist, the ray-path search
algorithm in [19] and [20] employs the visibility graph to limit the intersection test. The
visibility graph contains several layers. The first layer includes all objects visible to the
Tx (for LOS rays).
The second layer contains objects visible to the first layer (for transmitted,
reflected, and diffracted rays). Further layers are of similar recursive relationship. Since
the determination of visibility between two objects is not easy, acceleration methods
such as bounding boxes are employed for establishing the visibility graph.
32
When a ray is launched from the Tx, only those objects in the first layer of the
visibility graph need to be tested for the first intersection. To determine the
th
intersection of the ray, only objects in the n th layer need to be tested, thus leading to
saving of computing time. This method has similar drawbacks to the AZB method, i.e.,
when interaction levels are high, the establishment of the visibility graph will be much
more time consuming and complicated.
3) Dimension Reduction Method: To achieve efficient ray-tracing procedures
and retain acceptable accuracy, ray-tracing algorithms may be carried out in nonfull 3-D
geometries. Examples of this approach may include the 2-D/two-and-one-half
dimensional (2.5-D) method, the vertical plane launch (VPL) method, and so on. The
following is a brief summary of some of these methods.
a) 2-D/2.5-D Method: When the heights of buildings in a region are much larger
than the height of the Tx, the main propagation is a lateral one. In this case, the complex
3-D environment can be approximated by much simpler 2-D structures and a significant
saving in computation time can be achieved. Rizk et al. [21] presented a 2-D ray-tracing
modeling method for micro-cellular environments. Based on the image method, the
obtained prediction results compared well with measurement data.
b) VPL Method: The VPL technique is proposed in [11]. The usual 2-D ray
tracing is used in the horizontal plane. Each ray in the 2-D case represents a vertical
propagation plane. When a ray hits a vertical wall, specular reflection from the vertical
wall and diffraction from the rooftop horizontal edge can occur. When the ray hits a
vertical edge, diffraction also occurs.
The over-rooftop diffraction creates two vertical propagation planes, one in the
same direction as the incident ray and the other in the direction of reflection. Diffraction
from the vertical edge creates a new source and many new rays in 2-D planes should be
launched. These rays are further traced in a similar manner until some criteria are
reached. Fig. 2.8 is a schematic illustration of the VPL method [11].
33
Rizk et al. [22] compared the results using lateral, full 3-D, and VPL methods. It
is found that when the average building heights are around the Tx height, VPL can give
very good predictions.
Figure.2.8: Schematic illustration of the ray-launching procedure in the VPL [3]
4) Space-Division Method: The space-division method is widely used in
computer graphics[3]. The basic idea is to first create a grid (usually rectangular) in the
propagation environment, and then establish a lookup table registering objects residing
in each grid cell. When a ray is launched, it is traced in the grid. For each grid the ray is
traversing, the lookup table is checked to see if any objects reside in the grid. If yes, the
ray is tested for intersection with these objects. If any object is hit, a reflected (or
diffracted) and/or a transmitted ray will be created and the new rays will be further
traced.
The space-division method can give fast ray traversing and efficient ray tracing.
This is due to the fact that the algorithm for traversing the grid can be fast and the
intersection test is performed only on a small number of objects. Two types of spacedivision methods that have been applied to propagation in urban environments will be
summarized in the following subsections.
34
2.6.4 Accuracy of Ray-Tracing
The ray-tracing method can provide site-specific predictions. Due to the fact that
the environmental database may not be accurate and the materials of the objects in the
region of interest may not be known, the ray-tracing method can only provide approximate results for realistic propagation environments.
Another factor affecting the accuracy of the ray-tracing procedure is the
incomplete account for all kinds of rays. This is because the more rays taken into
account, the more computation time will be needed, leading to unacceptable efficiency.
On the other hand, the UTD/GTD (Geometrical Theory of Diffraction) model
may introduce several errors, among them are the error inherent in UTD due to the finit
size of the obstacles, the approximation in the treatment of reflection and diffraction in
dielectric material and also the assumption that surface is smooth and do not give diffuse
scattering. Besides, error in the ray-tracing algorithm in its code implementation also
appear. The code and the ray-tracing algorithm can never be sure that they run as the
way they were planned.
2.6.5
Conclusion
The tremendous development in wireless communications leads to the
emergence of new ideas and techniques to increase capacity and improve the QoS.
Smaller cell sizes, higher frequencies, and more complex environments need to be more
accurately modeled and site-specific propagation prediction models need to be
developed to achieve optimum design of next-generation communication systems. New
techniques such as smart antennas and multiinput and multioutput systems need new
propagation prediction models to characterize the joint spatio-temporal channel.
CHAPTER 3
BROAD BAND CHANNEL CHARACTERISTICS
3.1
Wireless LAN and IEEE 802.11a/g
As of today, the wireless LAN is arguably the most popular broadband wireless
network in the world. Standard LAN protocols, such as Ethernet, that operate at fairly
high speeds with inexpensive connection hardware can bring digital network to almost
any computer. The IEEE standard for wireless LANs (IEEE 802.11) introduces mobility
and flexibility to a LAN environment by allowing computers and other devices to
communicate with one another wireless. This technology is beneficial for improved
access to fixed LAN and inter-network infrastructure (including access to other wireless
LANs) via a network of access points, as well as creation of higher ad hoc networks.
The wireless LAN solutions that utilize OFDM are 802.11g and the802.11a. The
IEEEs 802.11g standard is designed as a higher-bandwidth (54Mbps) successor to the
popular 802.11b, or the Wi-Fi standard (11Mbps). While 802.11g is backwards
compatible with 802.11b at the 2.4GHz ISM (Industrial, scientific and medical) band,
802.11a operates in the newly allocated UNII band (Unlicensed National Information
Infrastructure). Figure (3.1) shows the frequency channel plan and the associated
maximum emission of the UNII band. Because of the power limitation, most applications
of wireless LAN are limited to home and office buildings.
36 0.8W
0.2W
20MHz channels
0.04W
…
5.15GHz
5.25GHz
…
5.725GHz
Figure 3.1: Maximum emission in the UNII band
The basic requirements of wireless LAN include
¾ Single MAC support multiple PHYs
¾ Overlap of multiple networks
¾ Robustness to interference
¾ Mechanics to deal with hiden nodes
¾ Provision for time bound services
Table (3.1) the 802.11a/g modem parameters
Data rate
6, 9, 12, 18, 24 ,36 , 48, 54 Mbps
Modulation
BPSK, QPSK, 16-QAM, 64-QAM
Coding rate
1.2, 2/3, 3/4
Number of subcarriers
52
Number pilots
4
OFDM symbol duration
4 us
Guard interval
800ns
Subcarrier spacing
312.5KHz
-3 dB bandwidth
16.56MHz
Channel spacing
20MHz
37 To meet these requirements, a number of challenges must be addressed. The
802.11a/g utilizes an OFDM modem to deliver a range of data rates from 6 Mbps up to
54 Mbps. Even higher speed versions (802.11n) are being rectified to blast data rate
beyond 100 Mbps. The parameters of its OFDM modem are summarized in Table (3.1)
At the current stage, the major limitations of the wireless LAN are its coverage
(several hundred feet) and quality of service (QoS) Support. While the coverage issue is
more regulatory than technical, the lack of QoS is inherent due to 802.11’s contention
based MAC are ongoing to expand support for LAN applications with quality of service
requirements.
The 802.11e is a working group to provide improvements in security and protocol
capabilities and efficiency. These enhancements, in combination with recent
improvements in PHY capabilities from 802.11a and 802.11b, will increase overall
system performance and expand the application space for 802.11.
Expand applications include transport of voice, audio and video over 802.11
wireless networks, video conference, media stream distribution, enhanced security
applications, and mobile and nomadic access applications.
3.2
Broadband Radio Channel Characteristics
Two difficulties arise when a signal is transmitted over the wireless medium. The
first is envelope fading, which attenuates the signal strength in an unpredictable way. The
other is dispersion, which alters the original signal waveforms in both time and
frequency domains.
38 3.2.1
Envelope Fading
The envelop fading manifests itself in the form of fluctuations in amplitude of
received signal. The main causes are multipath reflections. When the transmitted signal
arrives at the receiver through two paths with negligible delay between them. The
random scattering gives rise to different path attenuation in
X (t) =
1 s(t)
+
2
s(t) = (
1
+
2
1
2.
[14].
)s(t).
(3.1)
In this case, the channel response can be modeled as a single delta function with a
random envelop. Assuming
envelope of their sum, r =
1
1
+
2
are equal strength complex Gaussian, then the
, obeys a Rayleigh distribution:
2
=
(3.2)
With the mean and the variance
E{r} =
,
2
r
=
2
(3.3)
In the case when the multipath components are of the same strength (like
dominant line-of-sight scenario), the envelope can be more accurately described by the
Rican distribution.
3.2.2
Time Dispersive Channel
Multipath can be represented as a linear transform function h(t). Because of the
different propagation delays, the channel impulse response is superposition of delayed
delta functions equation (3.4). Whether these delays smear the signal depend on the
39 product bandwidth and the maximum differential delay spread [14]. A pictorial view of
the time dispersive channel is depicted in Figure (3.2).
h(t).= ∑
i
(t -
)
(3.4)
In the case Figure (3.2,) M = 2.
narrowband signal (flat channel)
h(t)
H(ƒ)
wide band signal(frequency
selective channel)
Delay spread
t
f
Figure 3.2: A time dispersive (frequency-selective) channel and its effect on
narrow-and broadband signals
Since the multipath delay, {
} are distinct, the frequency response of
H(ƒ) = Ŧ {h(t)}will exhibit multipath fluctuation. Such fluctuation in the frequency will
distort the wave form of broadband signal. More specifically in digital communication, a
channel is considered frequency-selective if the multipath delays are distinguishable
relative to the symbol period
-
:
(
-
) × (BW of signal) 1 (3.5)
On the other hand, if the signal bandwidth is sufficiently narrow, the channel
frequency response within the signal bandwidth can be approximated as constant. A
wireless channel is considered flat if the multipath delays are in distinguishable relative
to the symbol period: equation (3.6).
40 -
(
) × (BW of signal)
-
1
(3.6)
short symbol: time non selective
D(ƒ)
r(t)
Long symbol: time
selective
∆ƒ1 ∆ƒ2
ƒ
(a) Doppler effects
t
(b) Time selective\non selective
Figure 3.3: A frequency dispersive (time selective) channel and its effect on short
and long symbols
The often used parameters in characterizing a time dispersive channel include:
mean excess delay, root-mean squared (rms) delay spread:
coherence bandwidth:
3.2.3
, excess delay spread and
.
Frequency Dispersive Channel
The-short term fluctuation of the received signal in time domain can be best
explained by the Doppler effects due to movement of the transmitter, the receiver, or the
environment.
The Doppler introduce two types of distortion effects to the received signal:
signal variation over time, and broadened signal spectrum. Define channel coherence
time as
= 1/∆ƒ
(3.7)
41 Where the ∆ƒ
is the maximum Doppler frequency. When the Doppler shift
is comparable to the signal bandwidth (coherence time ~ the symbol period), the channel
is termed time selective (fast fading) or frequency dispersive.
On the other hand, if the Doppler shift is insignificant relative to the symbol rate
(channel coherence time
symbol period), the channel is termed nonselective (slow
fading) [23].
3.2.4 Summary
Envelope fading affects the signal strength and therefore fading margin in link
budget calculation of the wireless system. Power control and spatial diversity techniques
are among the most means to cope with envelope fading.
Frequency-selective fading alters the signal waveform and therefore the detection
performance. Traditionally, channel equalization is utilized to compensate the effect.
Alternatively, one can overcome the frequency selectivity by transferring a broadband
signal into parallel narrow streams.
Time-selective smear the signal spectrum and introduces variation too fast for
power control. Time interleaving and diversity techniques are most effective means of
coping with time-selective fading.
CHAPTER 4
RAY TRACING PROPAGATION PREDICTION
4.1
Introduction
Modeling the radio channel is a fundamental to predict the performance of
wireless radio system. Consequently, there have been many researchers over the past
several decades that have created channel models. Choosing and applying the
appropriate model is an important aspect of wireless system design. From the three basic
model classifications explained in chapter 2, site-specific ray tracing prediction model,
which is one of the physical models, is the best choice for fixed broadband wireless
system [24].
Ray tracing propagation models find dominant propagation paths and exhibit an
accuracy and efficiency over small ranges in urban area. These methods model the
physical paths and the mechanisms by which radio signals propagate from transmitter to
receiver. By using databases of the buildings and terrain at a specific site, rather than
using statistic averages, the true signal characteristics at the actual location can be
calculated and not those of an average or representative environment. This chapter
begins with a site survey and an introduction towards the ray tracing simulation
technique that applied in this research. This propagation model is based on VPL
technique. It is developed by Liang and Bertoni [11]. It covers frequencies 100 MHz and
above. The input parameters and databases for this simulation tool are described.
43 4.2
Site Survey
Before ray tracing propagation prediction, a visit to the related site is carried out.
The site constructed with buildings with mostly three floors. Transmit site is at fellow
office and it is higher than the other hostels by only few meters but the antenna is raised
up four times the receiver high the distance from the transmitter building till the receiver
building its like 113.6 meters. The site overlooked terrain of light rolling hills from the
fellow office you can easily see the hustle where the transmitter stands. Figure 1.2 shows
the site actual area from
which the transmitter stands there till
which the
receiver is.
4.3
Introduction to VPL Tool
Vertical-Plane-Launch (VPL) method provides a full three dimensional (3-D)
solution with computationally fast way to determine contributing rays and yields an
accurate propagation prediction. The VPL method considers specular reflections from
vertical surfaces and diffraction at vertical edges. It also allows approximation of
diffraction at horizontal edges along the plane of incidence.
The advantage of the VPL over full 3-D shoot and bounce ray (SBR) method is
that it can handle many multiple forward diffraction at horizontal edges. Besides this, the
VPL method provides many other advantages. The VPL method is applicable for rooftop
antenna and areas with mixed building heights that can not be properly handled by
vertical-plane/slant-plane (VP/SP) approximation.
The VPL method applies standard shoot and bounce method only at the
horizontal plane and use deterministic approach to determine the vertical displacement
of ray paths.
44 VPL takes account the nearly universal use of vertical walls in building
construction and differentiates the horizontal and vertical directions. In the horizontal
directions, 2D rays representing the vertical planes are launched from the source. This
method generates a binary tree at the point where the vertical plane intersects an exterior
face of a building wall, with one plane continuing along the incident direction and a
second plane going off in the direction seculars reflection as shown in Figure 2.8.
The plane that continues in the incident direction contains rays that propagate
directly over the building and rays that are diffracted over the buildings at its horizontal
edges. The plane that is spawned in the reflected direction contains rays that are either
secularly reflected from the building face or are diffracted at the top horizontal edge of
the wall. The path that a ray travels in the vertical direction is found by examining the
profile of all the buildings in the unfolded set of vertical plane segments between the
source and receiver and uses deterministic equation to calculate the vertical
displacement and received signal strength. A vertical plane segment is considered to
have illuminated the receiver if the ray intersects the capture circle of a receiver and lies
in the vertical wedge of the illumination
4.4
Algorithm of Simulation Software
The ray architecture is described by the flow chart shown in the Figure 4.1.
Firstly, the functionalities used to determine if a vertical plane intersects with the walls
of the building. Secondly, it determines whether a receiver will be illuminated by the
vertical plane and calculates the path loss associated with this path. And thirdly, it finds
all the vertical building corners that will be necessary to subsequently determine the
diffracted field at a receiver.
In this ray-tracing program, each of the vertical plane generated from a source
goes through all of the above three modules. Several assumptions have been made in this
45 program. The VPL method neglects diffuse scattering from the walls, rays that travel
under a structure and also reflections from the rooftop that travel upward and hence
away from the buildings and receivers. These simplifications are made because it is
believed that the rays do not contribute to the total received power in a micro cellular
environment, or that they occur very infrequently, and their inclusion would
substantially increase the model complexity and computation time.
Figure 4.1: Flow Chart of VPL Program [11]
46 4.5
Data for Simulation
There are four types of databases needed to run this simulation completely:
building database, receiver database terrain elevation database and antenna radiation
pattern database. The building database gives relative location of the building within the
predication area, whereas the receiver database contains the coordinates of the receiver
points. Terrain elevation database is used to model the effect of the ground on the ray
path. Antenna radiation pattern database gives the radiation pattern of the antenna at
every one degree. Building interior database is excluded in simulation, as it is only
needed when a receiver or a transmitter is placed inside a building. Here only outdoor
radio wave propagation prediction is concerned, thus building interior database is
neglected
4.5.1
Building Database
The building database is an American Standard Code for Information
Interchange (ASCII) file, which contains six columns of integer and floating-point
numbers that represent the building. The first column is a unique building identity
number that must be different from the building number before and after. The X and Y
coordinates are entered as a relative position from an arbitrary fixed reference position
of the database coordinate system in next two columns. The Z coordinates represent the
height of the building above the reference plane, and the vertical distance that the corner
of the building extends downward from Z are in the forth and fifth column. Integer of
the final column in the database is representing the relative dielectric constants. The
recommended dielectric constant is 6 because it provides the least error compared to
other values [11].
In reality many buildings have a more complex composition. The representation
of these multi-structure building is similar to the case for the single structure building.
47 Each distinct structure of the building is treated separately and entered into the database
in the same convention as in the single structure building case. In other words, each
structure is treated as a simple building even if it is merely a part of a complex building.
The program also has the capability to handle slant and peaked roofs for the buildings
with the prediction area. The procedure for handling this type of structure is similar to
that for a flat roof except that we now partition the roof of a single building into two
slanted surfaces.
4.5.2
Receiver Database
The receiver file is also in multi-column format, with each line containing the
coordinates of a single receiver point. The first column represents the receiver number
and the following three columns represent the location of the receiver in x, y and z
coordinates, with respect to the building database coordinate system. The z value of the
receiver point is the height of the ground at the point and not the absolute height of the
receiver. The height of the receiver above the ground, which is specified by the user in
the command line input, is added to the z value to get the actual height of the receiver.
The receiver database for simulation contains all the possible locations for receivers, but
in our case point to point there is only one receiver.
4.5.3
Terrain Elevation Database
Terrain elevation database is similar to a commercial used digital elevation map.
It is representing the terrain information to model the effect of the wound on the ray
path. Coordinate z at a particular (x, y) position is representing the height of the ground
above the fix reference. The complete file of these terrain points (x, y, z) can be viewed
as a grid for simulation area. The terrain database should be as large as possible to
48 support all the rays propagating from the transmitter to the receivers. This prediction
area covers 270 X 370 meter2. The same building database and terrain database will be
used in the simulation to predict and analyze the result on the receiver point. Part of the
actual databases, which are used for simulation, can be seen from Appendix A.2. to
A.2.4. Fig 4.2 and 4.3 shows the visualization of the Transmitter, Receiver and terrain
databases for the software.
4.5.4 Antenna Radiation Pattern Database
Antenna radiation pattern and gain are also important inputs in the software.
Market available planar array directional antennas are used in the wireless measurement
for both the transmitting and receiving sites. Unlike omnidirectional antenna that used in
mobile systems, the received power can be higher as much as the antenna’s gain, but
only if the arriving rays lie in the angular range of main lobe [5]. Before wireless
prediction and measurement being carried out, is a need to verify the antenna radiation
pattern and the gain of the antenna
As needed in the ray tracing simulation, measurement of radiation pattern and
gain of the antenna at 5.8 GHz has been carried out in an anechoic chamber following
the procedure which printed in[25], [26].. Two 2D patterns have been measured. They
are the x-z plane (elevation plane;
= 0), which represents the principal E- plane and
the x-y plane (azimuthally plane; θ= ), which represents the principal H- plane.
Antenna gain for both transmitter and receiver is 17dBi in. Part of the antenna radiation
pattern database is presented in the Appendix A.2.3. Figure 4.4 (a) and (b) shows the
radiation pattern in polar-logarithmic form, principal E which is a vertical plane-and
principal H which is the horizontal plane.
49 Figure 4.2: Terrain visualization
Y‐ Coordinate (meter) X‐Coordinate (meter)
Figure 4.3: Receiver visualization
(a) Horizontal-Plane (Azimuth)
(b) Vertical-Plane (Elevation)
Figure 4.4: Radiation pattern in polar-logarithmic
50 4.6
Simulation Command Input
The ray-tracing program is run in DOS mode where it performs command line
execution. Three arguments are required to initialize the program with a fourth argument
being optional as shown in the first command input in Table 4.1. The first argument is
building database file name, the second argument is receiver location file name and the
third argument is output file name. The optional input is the preprocessed data file name.
The associated directory of each file name must be defined correctly. After the program
has been initialized correctly, two lines of information are displayed as second command
input in Table 4.1. If the preprocessed input file name is not given at the initialization
stage, a question will prompt user to decide whether to have a preprocess run again.
Then, the program starts requesting a series of input parameters as listed in Table
4.1. The input parameters are in Italic font. Details of each input command line and
explanations are available in Appendix A.1. Number of grids in x and y, grid size, and
transmitter coordinates are varying depending on the input information such as building
and receiver database information. Once all required input parameters have been entered
correctly, the program starts executing the ray-tracing simulation. While the program is
running, information is continuously displayed and scrolled up. At the end of the
simulation, the program is terminated and returned back to DOS prompt again.
4.7
Output of the Prediction Tool
There are 3 types of outputs generated by the prediction program. They are
power and delay spread output, impulse response output, and ray paths information
output. Either power and delay spread output or impulse response output can be
produced in a simulation. It means two simulations are needed to produce both the
output files. On the other hand, ray path information outputs that contain the individual
ray paths for the receivers can be obtained together with any of the two output files.
51 Table 4.1: Command Input Simulation
No
Command Input
1
E:\…..\runvpl <building database file> <receiver location file> <output file>
[<preprocessed input>]
2
Site Ware Technologies Inc.
Site Specific Propagation Prediction Tool, ver 1.0 28SEP99
No preprocessed file was specified.
Do you want to do a preprocess run? [y/n]: n
3
4
Enter the angle that the ray trace will increase by: 1
Enter the maximum number of reflections to calculate: 10
5
6
7
8
Enter the number of diffraction at vertical edges that will be computed: 2
Enter the number of operating frequencies: 1
Enter the value of frequency I [MHz]: 5805
Enter the Fresnel zone width used to test screens: 1
9
10
Consider terrain using digital elevation database? [y/n]: y
Enter the filename of digital elevation database? : te.txt
11
12
Impulse response or power & delay spread output? [i/p]: p
Is directional antenna used? [y/n]: y
13
14
Output individual ray path data? [y/n]: y
Enter the x coordinate of the transmitter: 626480.0
15
16
17
18
Enter the y coordinate of the transmitter: 172268.5
Enter the z coordinate of the transmitter: 30.3
Number of different transmitter heights at (x,y,z): 1
Enter height 1 of the transmitter: 12
19
20
Enter the height of the receivers: 3
Use polynomial fit or read data file for the radiation pattern? [p/f]: f
21
22
23
24
Enter the name of the radiation pattern data file for 5805MHz: rd.txt
Enter the antenna gain at 5805MHz <dB>: 17
Enter tilt angle of the main beam relative to horizontal <E-plane>: 0
Enter azimuth angle of the main beam relative to due east <H-plane>: 0
52 4.7.1
Power and Delay Spread Output
The power and delay spread output file contains the predicted path loss for
receivers, a section that contains the different components that add together to get the
total power received, rms delay spread and mean excess delay. The results for each
receiver are listed in a multicolumn format on a single line with brief heading describing
the program execution parameters. Below the headers, the first column represents
receiver numbers while second to fourth columns list the x, y, and z coordinates for
those receivers. The fifth column is the predicted path loss value in dB. The column after
in between vertical line ( | ) separators is breakdown of the total power received into its
separate components. The first two columns indicate value in watt and number of LOS
rays. The second two columns show value in watt and number of reflected rays that
arrived at receiver. The third and forth two columns indicate value in watt and number
of rays that undergo 1 and 2 vertical edge diffraction beside on top of reflection. The
final two columns of data represent the rms delay spread and the mean excess delay in
seconds. Figure 4.5 is an example of power and delay spread output. Complete output
for the prediction in the related sites is given in Appendix A.3.
4.7.2
Impulse Response Output
In this result, the header is same with the one used for the power and delay
spread. Below the header is the individual path information according to the receiver.
The first line is the receiver number and the x, y, and z coordinates of the receiver.
Listed below the receiver are the individual rays contributed at the receiver. The
columns represent the angle at which the ray left the transmitter and path length of the
ray in meters, the propagation time in seconds and the predicted path loss in dB. The
fifth and final column is numerical representation of the type or class of ray. Example of
impulse response output is displayed in Figure 4.6.
53 4.7.3
Ray Path Information Output
The ray path information is stored in separate file for each receiver in every
simulation. These outputs generate details of each ray path that arrive at a particular
receiving point. Each group of information starts with a # sign heading representing a
single ray path as shown in Figure 4.7. The heading with a # sign shows the total path
length and total path loss associated with the ray. Information below the heading is a list
of x, y, z coordinates for all ray segments that combine together to form a complete path
from source to receiving point. The number of ray paths that arrives at a particular
receiving point is depending on the simulation output.
Header Receiver Receiver Path Power received Number Coordin‐
ate Loss For components Rms Delay Mean Excess Spread Delay Figure 4.5: Power and delay Spread Output
54 Header Receiver Rays Number & Contributed at a Coordinate Receiver Angle Path length Propagation time in Meters Seconds Path loss (dB) Class of ray Figure 4.6: Impulse Response Output
Length and path Coordinates Loss of each ray For all ray segments
Figure 4.7: Ray Path Information Output
55 4.8
Result Visualization
Matlab is a high-level technical computing language and interactive environment
for algorithm development, data visualization, data analysis, and numerical computation.
It includes a set of low-level file input output (I/O) functions that are based on the I/O
functions of (the American National Standards Institute ANSI) Standard C Library.
Here, a Matlab code that is similar to C language is written to extract data from the
numerical input and output files from the VPL ray tracing software. The data are then
presented in a 3D graphic display. The Matlab code written is presented in Appendix
C.4. Figure 4.8 shows the window of Matlab when the written Matlab code is running. A
figure 4.9 and 4.10 shows the visualization of the output. It supposes to be the building
profile and the terrain profile on the same layout but due to many difficulties and lack of
time they are in individual figures.
Figure 4.8: VPL Output Visualization Using Math lap
56 Figure 4.9: Ray visualization in(Y, X, Z) Coordinates from front Angle
For obstructed receiver
Figure 4.10 Ray visualization in(X, Y, Z) Coordinates from side Angle
For obstructed receiver
57 4.9
Summary
Accurate prediction of radio wave propagation in a communication channel is
essential in the development and design of an efficient and low cost wireless system.
This chapter introduces a physical based approach, known as VPL ray tracing modeling
to give channel characterization into mechanisms of radio propagation and inherently
provides highly accurate results. With this as a motivation, this propagation and channel
modeling is being pursued at the newly constructed hostels in UTM, which covers area
of 370 X 270
Matlab software.
. The obtained numerical output files are being visualized using
58 CHAPTER 5
TEST BED OF WIRELESS CAMPUS
5.1
Introduction
The test bed is prepared to act as a platform for networking configuration,
testing and training to staff involved in wireless campus project. This is also to ensure
before any implementation or changes are made to the real time networking system,
administrator can actually perform a testing step through the test bed system without
any service interruption to subscriber. Further more, the test bed demonstrates concept
and model of wireless campus.
FLAT ANTENNA
PtP
Figure 5.1: Wireless campus test bed system [27].
59 MikroTik Router OSTM is independent Linux-based Operating System for PCbased routers and thinrouters. It does not require any additional components and has no
software pre-requirements. It is designed with easy-to-use yet powerful interface
allowing network administrators to deploy network structures and functions. Mikrotik
Router OSTM V2.7 is the networking operating system that used in configuring IP
address routing, interfaces setting, bridging, wireless interfaces setting, DHCP client
and server, IP pool management, authentication and etc. The test bed consists of FLAT
antenna for point to point and also point to multipoint at 5.8GHz, Mikrotik radio unit
and monitoring PC. This chapter shows the system construction and system setup. The
main from this chapter is the construction of the point to point 5.8 GHz
MikroTik Router OSTM turns a standard PC computer into a network router.
Just add standard network PC interfaces to expand the router capabilities [27]. The
features of MikroTik Router OSTM are mentioned below.
Remote control with easy real-time Windows application (WinBox)
Telnet/console/serial console control
Advanced bandwidth control
Network firewall with packet-filtering, masquerading, network address translation,
logging and network monitoring
DHCP support
Hotspot technology
Ethernet 10/100/1000 Mb/s
Wireless client and AP 2.4GHz II Mb/s
V.35 synchronous 5Mb/s with frame-relay
Asynch PPP/RADIUS (up to 32 ports) for modem pools
Cyclades with El/T1 support
IP Telephony Gateway
Built-in Web-proxy and etc
60 5.2
Setting up the MikroTik Router OSTM
Figure 5.2: Download and installation process of MikroTik Router OSTM
Depending on the desired media to be used for installing the MikroTik
RouterOSTM, choose one of the following archive types for downloading, in this case
ISO image was used.
ISO image- The ISO image is in the MTcdimage_v2-7—xdd—mmm—
yyyy.zip archive file containing a bootable CD image. The CD will be used for
booting up the dedicated PC and installing the MikroTik Router OSTM on its harddrive or flash-drive [28].
MikroTik Disk Maker- To create 3.5" installation floppies. The Disk Maker is
a self—extracting archive DiskMaker_v2-7—x dd—mmm—yyyy.exe file, which should
be run on your Win95/98/NT4/21(AP workstation to create the installation
floppies. The floppies installation will be used for booting up the dedicated PC and
installing the MikroTik Router OSTM on its hard—drive or flash—drive.
61 Netinstall, if you want to install Router OSTM over a LAN with one floppy
boot disk, or alternatively using PXE—boot option supported by some network interface
cards, that allows truly networked installation.
The installing process of the test bed was continuing by creating ISO image
archive onto a blank CD. A secondary master CD drive set as primary boot device for
installing the Mikrotik Router OSTM onto the primary master HDD. A monitor and
keyboard does not need to be connected to the router after installation process
completed.
After successful installation, remove the installation media and reboot the router.
While the router will be starting up for the first time administrator will be given a
Software ID for your installation and asked to supply a valid software license key
(Software Key) for it. The software ID will be required to obtain the Software License
through the MikroTik Account Server [27].
5.2.1 Logging into the MikroTik Router
When logging into the router via terminal console, administrator will be
presented with the MikroTik RouterOSTM login prompt. Use `admin' and no password
(press 'Enter') for logging on to the router. For example:
MikroTik v.2.7
Login:
admin
Password:
The password can be changed with the `/password command'.
62 5.2.2 Adding Software Packages
The basic installation comes with only the system package and few other
packages. This includes basic IP routing and router administration. To have additional Features such as IP telephony, OSPF, wireless and so on, additional software
packages are required.
The additional software packages should have the same version as the system
package. If not, the package won't be installed. Please consult the MikroTik
RouterOSTM Software Package Installation and Upgrading Manual for more detailed
information about installing additional software packages.
5.2.3
Software Licensing Issues
In order to upgrade to a 'paid' version of MikroTik RouterOSTM installation, the
new Software License KEY must be purchased for the software ID that currently in use.
Similarly, if additional license is required to enable the functionality of a software
package, the license should be obtained for the Software ID of your system. The new
key should be entered using the `/system license set key' command and the router
should be rebooted afterwards:
5.3
Navigating Terminal Console
After logging into the router you will be presented with the MikroTik
Router OSTM Welcome Screen and command prompt, for example:
63 MMM MMM
KKK
TTTTTTTTTTTKKK
MNMM MMMM KKK
TTTTTTTTTTTKKK
MMM CQ44M MMM III KKK KKK RRRRRR 000000
TTT
III KKK KKK
MMM MM MtM M III KKKKKRRR RRR 000 000
TTT III
KKKKK
MMM MMM III KKK. KKK. RRRRRR000 000 TTT III KKK KKK.
MMM M M M I I I K K K . K K K R R R R R R 0 0 0 0 0 0
TTT
III KKK KKK
MikroTik Router OS v2.7 (c) 1999-2003 http://www.mikrotik.com/
Terminal xterm detected, using multiline mode
[admin@MikroTik] >
The command prompt shows the identity name of the router and the current menu
level as shown below:
[admin@MikroTik] > Base level menu
[admin@MikroTik] interface> Interface configuration
[admin@MikroTik] ip address> IP Address management
5.3.1
Web Browser and WinBox Console
The MikroTik router can also be accessed remotely using http and WinBox
Console as shown in Figure 5.3. WinBox Console is used for accessing the MikroTik
Router configuration and management features using graphical user interface. All
WinBox interface functions are as close as possible to Console functions: all WinBox
functions are exactly in the same place in Terminal Console and vice versa (except
functions that are not implemented in WinBox).
64 Figure 5.3: Win Box Console
5.4
Configuration of MikroTik PC Router
Before configuring the IP addresses and routes please check the `/interface'
menu to see the list of available interfaces [27]. If a plug and play cards installed
in the router, it is most likely that the device drivers have been loaded for them
automatically, and the relevant interfaces appear on the ‘interface print’ list.
Figure: 5.4 Network Setting for MikroTik PC Router
65 5.5
DHCP Client and Server
DHCP (Dynamic Host Configuration Protocol) supports easy distribution of IP
addresses for a network. The MikroTik RouterOS implementation includes both
server and client modes and is compliant with RFC2131.
General usage of DHCP:
IP assignment in LAN, cable—modem, and wireless systems
Obtaining IP settings on cable—modem systems
DHCP server can be used with MikroTik Router OS HotSpot feature to
authenticate and account for DHCP clients. The DHCP protocol gives and allocates IP
addresses to IP clients. DHCP is basically insecure and should only be used on secure
networks. DHCP server listens on UDP 67 port, DHCP client — on UDP 68 port.
Figure 5.5: Setting of MikroTik PC router in Win Box
66 Figure 5.6: Network of the test bed of wireless campus [27]
5.6
Summary
The microwave link is a part of Wireless Local Network and one of many
links which they are all together made the WLAN. This chapter gives an idea about
the whole system constellation as well as the link constructor. The chapter also talked
about the system installation but all the setup details appended to the appendix and
for the Radio Units only Radio unit#1 explained its installation and the rest are
similar.
67 CHAPTER 6
RESULT AND ANALYSIS
6.1
Overview
This chapter discusses the comparison between the simulation result and the real
time measurements of propagation prediction for one wireless system bridge link in
University Technology Malaysia. The study of outdoor propagation environment done in
order to obtain the best accuracy, efficiency and coverage of signal strength. A study to
the area where the microwave link stand first done to collect all possible observation and
then build the data base for the site which shown in appendix (c) after that the prediction
done. Signal strength reads taken from the receiving end of the microwave link which
represents real measurement side.
6.2
Measurement Result
In the previous chapter the system of point to point inside whole WLAN which
constructed and the entire configuration was made, to measure the signal strength on the
specified link a Laptop and connected it with the switch which connected to the receiver
to read the measurement
68 This measurement held on the link which stands from (
bridging link , signal which received on
to
) and its
was -64 dBm and the path loss is -82 dB.
The – 82 dB.path loss comes from the equation below:
(dB) =
(dB )
(dB )……………………….(6.1)
(dB) : the path loss in dB.
(dB ): the transmitted power indB .
(dB ): the received power indB .
The transmit power was 70 mW which is equal to 18 dB
and the power
received was – 64 dB , by using equation (6.1) the path loss is -82 dB.
A comparison between this value and predicted value fro Vertical Plane Launch
software will be shown later on. The value above taken from the receiving end bridge
directly, appendix () shows other similar link signal strength value which is – 67 dBm.
Table 6.1: Shows the signal strength in different data rates
Data Rare
Signal Strength
6 Mbps
-64 dB
9 Mbps
-64 dB
12 Mbps
-64 dB
18 Mbps
-63 dB
24 Mbps
-63 dB
36 Mbps
-66 dB
48 Mbps
-69 dB
54 Mbps
-72 dB
69 .
Figure 6.1: Measurement result
From Fig 6.1 it’s clear that when the signal strength is – 63 dB , a data rate till
24 Mbps can be achieved , for data rate more than 25 Mbps the signal strength will start
to drop till the signal strength reach – 72 dB at data rate of 54 Mbps. The conclusion of
the above that to achieve high data rate it is essential that the signal strength should be
very strong.
6.3
VPL Result and Analysis
The prediction which carried on the 5.805 GHz (UNII) band point to point link
within distance of 113.60 meters separating between the transmitter and the receiver
shows that the Path Loss is about –54 dB, .figure 6.2 shows the output of the prediction
70 tools, in the first line is the receiver number and the x,y,z coordinates of the receiver in
the second line the first column indicates the angle (in radians) at which at the ray left
the transmitter the second is the path length in meters and the value is 113.60 as
mentioned, the third column is propagation time in seconds which is equaled 0.379e-006
this value known as the mean excess delay ,the mean excess delay represent the time
which the signal takes to reach the receiver. The fourth column is representing the
predicted path loss in dB, the last column value -1 represent line of sight ray.
Figure 6.2: Prediction result
From the above Fig, at distance of 223 meters the signal strength was -83 dB
and at distance of 335 the signal strength was -93dB , that explains as the signal travel
further more signal strength decreases. It is clear from the figure that in signal strength
of -91dB
and -98dB the distant was 140 meter for both and this weakness of the
signal in small distance because of the signal undergoes diffraction which causes the
signal weakness. From the above observation the distant from the receiver to the
transmitter can affect the signal strength, but for short ranges of transmitting the factors
71 which influencing the performance are the multipath factors like: diffraction, reflection,
refraction, and that why in small distances the signal strength is weak as in Fig 6.2. The
power received from the prediction is equal to -36.83dB . Figure 6.4 shows the path
coordinates of transmitted signal which has only one path the line of sight.
On Figure 6.3, the column before the last on the figure shows that the r.m.s.
delay spread TRMS is the standard deviation (or root-mean-square) value of the delay of
reflections, weighted proportional to the energy in the reflected waves is0.0680e-009 ns
which is almost zero and that because there are only dominate line of sight ray no any
reflection or diffraction.
In indoor and micro-cellular channels, the delay spread is usually smaller, and
rarely exceed a few hundred nanoseconds. Seidel and Rappaport reported delay spreads
in four European cities of less than 8 microsec in macro-cellular channels, less than 2
microsec in micro-cellular channels, and between 50 and 300 ns in pico-cellular
channels [4].
For a digital signal with high bit rate, this dispersion is experienced as frequency
selective fading and inters symbol interference (ISI). No serious ISI is likely to occur if
the symbol duration is longer than, say, ten times the r.m.s. delay spread. The prediction
result above shows that the system can run with high bit rate without any problem of
(ISI).
Figure 6.3: Ray visualization
72 Figure 6.4: Prediction result impulse response output
Figure 6.5: Prediction result delay spread output
73 Figure 6.6: Result Ray Path
6.4
Comparison between Prediction and Measurement Result
The discussed ray tracing wave propagation prediction software tool is used to
compute the path loss value with respect to the slow fading process at the given receiver
locations. Visualizations were done on the receiver location in order to understand the
different ray components contained
The predictions loss for the microwave link from
28 dB more than
measurement data. The severe difference is due to the irregular vegetation effects in
Fresnel zone which is hard to model and is not considered in VPL ray tracing prediction.
The location is in LOS conditions. Hence to consider the obstruction loss of vegetation
in Fresnel zone, the deviation within free space loss and measurement loss will be used.
The free space loss model is used to predict received signal strength when the
transmitter and receiver have a clear, unobstructed LOS path between them. The
equation of the free space loss equation (6.2) is:
(dB) = 32.44 10log
10log
20log
20log
(6.2)
74 The predicted path loss from the VPL software tool was -54 dB, after using the
free space loss to correct the sever to the vegetation factor now the path loss is -64 dB.
The difference became now after the correction between predicted path losses of the
microwave link from
is about 18 dB.
The difference could be related to many reasons, one of them that the data base
which have been collected that they are not 100% accurate, the Radiation Pattern was
taken every two degrees then to make it suitable for VPL software the mean between
every two neighborhood degree are made to interpolate from two degree to one degree
difference and that get the corresponded power.
The previous operation has a great affect in increasing the radiation pattern and
that led to strong signal. The lake of accuracy of the building structure and that
represented by many errors in few building shape as depicted in Fig 6.6 in addition to
that many building are omitted from the predicted area all that together may led to have
signal stronger than the measured,.
By comparing the result collected from this work by the previous one [5]. In that
work the predictions loss for 24 locations has range from 3.61 to 33.03 dB less than
measurement data. The severe difference is due to the irregular vegetation and all the
locations are in LOS. Comparing the prediction outcome from the point to point link to
[5] work the 28 dB is inside the range from 3.61 to 33.03 dB.
When the signals arrives to the receiver there are usually a combination of direct
and indirect path, if the electromagnetic phase of the signals are the same, the signal
strength became much stronger, and if the electromagnetic phase of signals shifted or
inversed it will drop the signal strength. From the Fig 6.6 and the visualize of the output
shows the case of the obstructed receiver case , on this case we found that the path loss
is much higher because the signal as clearly visible in the figures are reflection from
surrounding objects .
75 CHAPTER 7
CONCLUSION AND FUTURE WORK
7.1
Conclusion
The objectives of the project have been achieved. The study on the outdoor
environmental effect, which affect the radio wave propagation and visualization of the
radio wave propagation with 3D dimensional introduces effect of reflection, diffraction,
delay spread and multipath fading have been done. The objectives to measure and
simulate signal strength for bridge link and compare between the prediction and the
measurements.
We found that the simulation software base on Site Specific Outdoor/Indoor
Propagation Prediction Code has high reliable and accurate prediction tool, since the
simulation result was closer to result that obtain from the measurement
We realize that there are various elements that can effect the radio wave
propagation, for instance, diffraction, reflection, refraction, multipath fading, delay
spread, Doppler frequency shift, noise and scattering. However, on this project we found
that most factor which affects the microwave link is the obstruction of the Fresnel zone
means unclear line of sight which might lead to block the receiver from the signal. Fig
6.3 shows a received signal by reflection only, this depicts the mentioned above
observation.
76 7.2
Future Work
In the future there are lots of improvements which can be done to enhance the
work which have been accomplished done: firstly the building database accuracy needed
to be increase because in the previous work the slop of the rooftop are ignored and the
presence of it might add much strength to the received signal, another factor which can
be enhanced that on the terrain profile where the buildings stand the bottom of the
building needed to be more accurately matched with terrain profile so as to get the exact
position and height of the building database.
The previous work which have been done for small area which called (short
distance microwave link and this work could basic start for doing point to point long
distance microwave links ,
Finally more subprograms can be written in Matlab or software to link with VPL
and make it to accept CAD building file automatically without have to construct again
use normal format to be more user-friendly.
77 REFERENCES
1.
Vijay K. Garg (2007). Wireless Communications & Networking, Pages 713-776. 2.
Kai Chang, RF Microwave Wireless Systems. Texas A&M University: John
Wiley & Sons, Inc 2000.
3.
Magdy, F. Iskander., Zhengqing, Yun. (2002). Propagation Prediction Models
for Wireless Communication Systems. IEEE Transaction on Microwave Theory
and Techniques, 50, 3.
4.
Rappaport, T. S. Wireless Communications Principles and Practice. 2nd. Ed.
Upper Saddle River, N.J 07458: Prentice Hall PTR. 2002
5.
Tang Min Keen (2005). Channel Modeling and Bit Error Rate Performance
Simulation for Fixed Broadband Wireless Systems. M.S. Thesis. Univesiti
Teknologi Malaysia, Skudai
6.
M. Hata, “Empirical formula for propagation loss in land mobile radio services,”
IEEE Trans. Veh. Technol., vol. VT-29, pp. 317–325, Aug. 1980.
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D. J. Cichon and T. Kurner. Propagation prediction models. COST 231 Final
Rep. [Online]. Available: http://www.lx.it.pt/cost231/ 8.
J.Walfisch and H. L. Bertoni, “A theoretical model of UHF propagation in urban
environments,” IEEE Trans. Antennas Propagat., vol. 36, pp.1788–1796, Dec.
1988 78 9
L. R. Maciel, H. L. Bertoni, and H. H. Xia, “Unified approach to prediction of
propagation over buildings for all ranges of base station antenna height,” IEEE
Trans. Veh. Technol., vol. 42, pp. 41–45, Feb. 1993. 10.
S. Y. Seidel and T. S. Rappaport, “Site-specific propagation prediction for
wireless in-building personal communication system design,” IEEE Trans. Veh.
Technol., vol. 43, pp. 879–891, Nov. 1994 11.
G. Liang and H. L. Bertoni, “A new approach to 3-D ray tracing for propagation
prediction in cities,” IEEE Trans. Antennas Propagat., vol. 46, pp. 853–863,
June 1998
12.
L. Piazzi and H. L. Bertoni, “Achievable accuracy of site-specific path-loss
predictions in residential environments,” IEEE Trans. Antennas Propagat., vol.
48, pp. 922–930, May 1999.
13.
S. Kim, B. J. Guarino, T. M. Willis, III, V. Erceg, S. J. Fortune, R. A.
Valenzuela, L. W.Thomas, J. Ling, and J. D. Moore, “Radio propagation
measurements and prediction using three dimensional ray tracing in urban
environments at 908 MHz and 1.9 GHz,” IEEE Trans. Veh. Technol., vol. 48, pp.
931–946, May 1999.
14.
H. Ling, R. Chou, and S. Lee, “Shooting and bouncing rays: Calculating the RCS
of an arbitrarily shaped cavity,” IEEE Trans. Antennas Propagat., vol. 37, pp.
194–205, Feb. 1989.
15.
J. O’Rourke, Computational Geometry in C. Cambridge, U.K.: Cambridge Univ.
Press, 1993.
79 16.
S. Y. Tan and H. S. Tan, “A microcellular communications propagation model
based on the uniform theory of diffraction and multiple image theory,” IEEE
Trans. Antennas Propagat., vol. 44, pp. 1317–1326, Oct. 1996.
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M. F. Catedra, J. Perez, F. S. de Anana, and O. Gutierrez, “Efficientray-tracing
techniques
for
three-dimensional
analyses
of
propagationin
mobile
communications: Application to picocell and microcell scenarios,”IEEE
Anntenas Propagat. Mag., vol. 40, pp. 15–28, Apr. 1998.
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F. S. de Adana, O. G. Blonco, I. G. Diego, J. P. Arriaga, and M. F. Catedra,
“Propagation model based on ray tracing for the design of personal
communication systems in indoor environments,” IEEE Trans. Veh. Technol.,
vol. 49, pp. 2105–2112, Nov. 2000.
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F. A. Agelet, F. P. Fontan, and A. Formella, “Fast ray-tracing for microcellular
and indoor environments,” IEEE Trans. Magn., vol. 33, pp.1484–1487, Mar.
1997.
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F. A. Agelet, A. Formella, J. M. H. Rabanos, F. I. de Vicente, and F. P.Fontan,
“Efficient ray-tracing acceleration techniques for radio propagation modeling,”
IEEE Trans. Veh. Technol., vol. 49, pp. 2089–2104, Nov. 2000.
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K. Rizk, J. Wagen, and F. Gardiol, “Two-dimensional ray-tracing modeling for
propagation in microcellular environments,” IEEE Trans. Veh. Technol., vol. 46,
pp. 508–517, May 1997.
22
K. Rizk, R. Valenzuela, S. Fortune, D. Chizhik, and F. Gardiol, “Lateral, full-3D
and vertical plane propagation in microcells and small cells,” in 48th IEEE Veh.
Technol. Conf., vol. 2, 1998, pp. 998–1002.
80 23
Hui Lui and Guoqing Li, “OFDM Based Broadband Wireless Networks Design
and Optimization, “John Wiley & Sons, Inc, Publication 2005.
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Anderson, H. R Fixed Broadband and Wireless: System Design. West Sussex
P0198SQ, England: John Wiley & Sons Ltd. 2003 25
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Test Procedures for Antennas. USA: ANSI/IEEE Std. 149-1979, 1979.
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Stutzman, W. L. and Thiele, G. A. Antenna Theory And Design 2nd. Ed. 605
Third Avenue: New York. Jhon Wiley & Sons, Inc. 1998
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So Hong Teck (2006). Characterization And Implementation of Radial Line Slot
Array Antenna At 5.8 GHz Test Bed Setup For Wireless Campus Project. M.S.
Thesis. Universiti Teknologi Malaysia, Skudai.
81 Appendix A:
Ray Tracing Propagation Prediction
A.1
Simulation Command Input
Site Specific Code is available for different type of simulation .The runtime
Parameter will be determined from the command line input during the simulation and
the output results are different depending on the input parameters. An example of
running the prediction program is shown in Figure A.1. First, we begin the execution of
the prediction program by typing the following.
runvpl < building file ><receiver point file><output file > [<preprocessed input
file>]
The command inputs are as follow:
•
Enter the angle that the ray trace will increment by:
The question prompts for the incremental angle between successive rays when launched
from a source. An integer fraction of 360° should be entered.
82 •
Enter the maximum number of reflections to calculate:
This parameter set the total reflection calculated during the program execution. There is
no upper limitation for the calculated reflections and the input should be an integer.
•
Enter the number of diffraction at vertical edges that will be computed :
It represents the number of levels of vertical edge diffractions that program will perform
.Only 0, 1 or 2 are valid inputs for this parameter.
•
Enter the number of operating frequencies :
This question prompts the user for the number of frequencies that program will predict
for simultaneously. Since the geometrical ray trace is identical at all frequencies it is
possible to perform one ray trace while producing results at a number of frequencies.
The responds to this question should be an integer number.
•
Enter the value of frequency 1 [MHz]:
•
Enter the value of frequency 2 [MHz]:
: : •
Enter the value of frequency n [MHz]:
This question will be asked n number of times for each frequency in MHz depending on
the number of frequencies entered in the previous question.
83 •
Enter the Fresnel zone width used to test screens:
The answer to this question sets the width of the Fresnel zone use within the program.
The program uses this criterion to test which screens are taken into accounted when
calculating diffraction over buildings. The input represents the Fresnel width with input
of 1 representing the first Fresnel zone. Any positive real number may be entered while
entering 0representa zero width.
•
Consider terrain using digital elevation database?[y\n]
The parameter requires an alpha input with a case insensitive y or Y representing ‘yes’
and n or N representing ‘no’. Answer will be n for indoor wireless.
•
Impulse Response or Power & Delay Spread Output? [i/p]
It prompts for one of two possible alpha responses, which determines the type of output
that is produced by the program. A lowercase ‘i’ response will direct the program to
produce a impulse response output while a lowercase ‘p’ will give an output that states
the total power received at each receiver point.
•
Compute with 2 ray model? [y/n]:
If yes is answered for this question the program will calculate the ground reflected ray
associated with each direct ray. The program will automatically determine the location
and refection coefficient for each direct ray based on a localize at ground model. 84 •
Impulse Response or Power & Delay Spread Output? [i/p]:
This question prompts the user for one of two possible alpha responses which
determines the type of output that is produce by the program. A lowercase “i” response
will direct the program to produce a impulse response output while a lowercase “p” will
give an output that states the total power received at each receiver point.
•
Output individual ray path data? [y/n]
This question asks the user whether individual ray paths for each receiver point should
be output to a file so that a visual picture can be constructed .the ray paths for each
receiver points are outputted into separate files labeled “ray paths rx#” where # is the
receiver number. Refer to the chapter on the output file format for details and
information contain in the ray paths file.
•
Enter the x coordinate of the transmitter:
•
Enter the y coordinate of the transmitter :
•
Enter the z coordinate of the transmitter
These question prompt for a numerical input to set the location of the transmitter when
the transmitter location is represented by the x and y coordinate while coordinate z
representing the height of transmitter from the ground level. If the transmitter is on a
rooftop location the z value should be the z of the position at the top of the roof(i.e. the
height of the roof) above some fix reference.
85 •
Number of different transmitter heights at (x,y,z):
This question asks for the number of transmitter heights that the program will
simultaneously simulate.
•
Enter height 1of the transmitter :
: : •
Enter height 2 of the transmitter:
This question prompts for the heights of the transmitter above the ground at transmitter
location (x,y,z) which wan entered previously. This value is added to the z location
value to obtain the absolute location of the transmitter in a 3 dimensional Cartesian
coordinates system.
•
Enter the height of the receiver :
It is referring to the height of the receiver above the ground and this value is added to the
z value of each receiver points in the receiver database.
The following set of questions appears after the previous set of questions if yes is
answered for the question regarding whether a directional antenna is used:
•
Use polynomial fit or read data file for the radiation pattern? [p/f]:
This question prompts the user for the polynomial order for the radiation pattern fit in
the H field plane.
86 •
Enter the name of the radiation pattern data file for xxx MHz:
The name of the file that contains the antenna radiation pattern database should be
entered. The complete path of the file can be entered to specify the relative location of
the file.
•
Enter the antenna gain at xxx MHz(dB):
This question sets the antenna gain for the antenna used at the xxx frequency.
•
Enter the tilt angle of the main beam relative to horizontal (E-plane):
This question prompts the user to set the tilt of the boresight of the radiation pattern in
the E plane. The tilt angle is specified in degrees relative to a horizontal boresight with a
positive value is used for an upward tilt and a negative value for a downward tilt.
•
Enter the azimuth angle of the main beam relative to due east (H-plane):
This question prompts the user for the boresight azimuth direction relative to the positive
x-axis and is specified in degrees.
87 Figure A.1 program running
88 A.2
Database for Simulations
A.2.1 Building Database (Part of BLD0.txt)
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 626445.4 626451.8 626459.4 626474.4 626482.4 626490.1 626487.2 626474 626468.6 626471.1 626468.5 626476 626477.8 626484.2 626491.3 626493.4 626491.3 626485.9 626480.2 626478.5 626470 626470.8 626462.4 626457.8 626451.8 626447.9 626434.8 626422 626410.9 626405.3 626408.8 626419.5 626421.7 626415.2 626418.4 626434.4 626445.4 626451.8 626459.4 172200.2
172215.5
172219 172214.2
172216.6
172231.8
172246 172250.6
172266.9
172272.6
172287 172284 172278.1
172275.3
172278.1
172284.2
172290.5
172293.4
172292.1
172287.7
172291.1
172294 172297.2
172285.6
172283.2
172276.3
172272 172276.5
172272.5
172259.4
172245 172240 172232.4
172214.5
172201.3
172195.9
172200.2
172215.5
172219 15.24 15.24 15.24 15.24 15.24 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 15.24 15.24 15.24 32.24 32.24 32.24 15.24 15.24 15.24 15.24 15.24 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 15.24 15.24 15.24 17 17 17 6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
89 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 626474.4 626482.4 626490.1 626487.2 626474 626468.6 626471.1 626468.5 626476 626477.8 626484.2 626491.3 626493.4 626491.3 626485.9 626480.2 626478.5 626470 626470.8 626462.4 626457.8 626451.8 626447.9 626434.8 626422 626410.9 626405.3 626408.8 626419.5 626421.7 626415.2 626418.4 626434.4 626444.6 626459.9 626462 626456.8 626448.9 626434.1 626430.4 626438.5 626444.6 626459.9 172214.2
172216.6
172231.8
172246 172250.6
172266.9
172272.6
172287 172284 172278.1
172275.3
172278.1
172284.2
172290.5
172293.4
172292.1
172287.7
172291.1
172294 172297.2
172285.6
172283.2
172276.3
172272 172276.5
172272.5
172259.4
172245 172240 172232.4
172214.5
172201.3
172195.9
172260.8
172253.5
172247.2
172230.5
172228.3
172237.2
172243.7
172259 172260.8
172253.5
32.24 32.24 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 35.288 32.24 32.24 32.24 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 22.288 22.288 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 17 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 4 4 6
6
6
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6
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6
6
90 2 2 2 2 2 2 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 4 4 4 4 4 4 4 4 4 4 4 4 5 5 5 5 5 626462 626456.8 626448.9 626434.1 626430.4 626438.5 626538.2 626538.2 626552.7 626552.7 626550.9 626550.9 626553.1 626553.1 626537.9 626552.9 626538.2 626538.2 626552.7 626552.7 626550.9 626550.9 626553.1 626553.1 626537.9 626552.9 626552.9 626550.8 626550.8 626552.4 626552.4 626537.8 626552.9 626550.8 626550.8 626552.4 626552.4 626537.8 626551.9 626551.9 626550.7 626550.7 626551.8 172247.2
172230.5
172228.3
172237.2
172243.7
172259 172305.7
172282.5
172282.5
172291.2
172291.2
172298.6
172298.6
172305.6
172340.4
172340.4
172305.7
172282.5
172282.5
172291.2
172291.2
172298.6
172298.6
172305.6
172340.4
172340.4
172333.3
172333.3
172327.1
172327.1
172318.2
172318.2
172333.3
172333.3
172327.1
172327.1
172318.2
172318.2
172354.7
172363 172363 172368.5
172368.5
22.288 22.288 22.288 22.288 22.288 22.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 31.288 31.288 31.288 34.336 34.336 34.336 34.336 34.336 34.336 34.336 21.336 21.336 21.336 21.336 21.336 21.336 34.336 34.336 34.336 34.336 34.336 34.336 24.384 24.384 24.384 24.384 24.384 4 4 4 4 4 4 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 18.288 13 13 13 13 13 13 13 13 13 13 21.336 21.336 21.336 21.336 21.336 21.336 13 13 13 13 13 13 24.384 24.384 24.384 24.384 24.384 6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
91 5 5 5 5 626551.8 626538.3 626538.3 626551.9 172377.4
172377.4
172354.6
172354.7
24.384 24.384 24.384 37.384 24.384 24.384 24.384 13 6
6
6
6
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
13 13 13 13 24.384 24.384 24.384 24.384 24.384 24.384 17 17 17 17 17 17 21.336 21.336 21.336 21.336 21.336 21.336 21.336 21.336 21.336 21.336 13 13 13 13 13 13 13 13 13 6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
10 10 10 10 11 11 11 11 11 11 11 11 11 11 11 11 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 626466.1 626468.3 626470.2 626470.2 626475.9 626478.9 626478.9 626455.9 626455.9 626470.2 626475.9 626478.9 626478.9 626455.9 626455.9 626470.2 626433.4 626433.4 626446.2 626446.2 626423.3 626423.3 626414.8 626414.8 626427.5 626427.5 626433.4 626433.4 626446.2 626446.2 626423.3 626423.3 626414.8 626414.8 626427.5 172389.2
172389.2
172390.9
172397 172397.2
172397.2
172405.8
172404.3
172395.7
172397 172397.2
172397.2
172405.8
172404.3
172395.7
172397 172399.6
172393.1
172393.1
172378.6
172378.6
172386.1
172386.1
172396.3
172396.3
172401 172399.6
172393.1
172393.1
172378.6
172378.6
172386.1
172386.1
172396.3
172396.3
37.384 37.384 37.384 37.384 24.384 24.384 24.384 24.384 24.384 24.384 41.384 41.384 41.384 41.384 41.384 41.384 21.336 21.336 21.336 21.336 21.336 21.336 21.336 21.336 21.336 21.336 34.366 34.366 34.366 34.366 34.366 34.366 34.366 34.366 34.366 92 12 13 13 13 13 13 13 13 13 13 13 13 13 14 14 14 14 14 14 14 14 14 14 14 14 14 14 14 14 14 14 14 14 14 14 14 14 14 14 14 14 14 14 626427.5 626433.4 626443.2 626443.2 626423.5 626423.5 626427.5 626433.4 626443.2 626443.2 626423.5 626423.5 626427.5 626537 626533.9 626529.7 626524.9 626532.5 626538.2 626545.8 626543.7 626555.9 626559.7 626561.6 626577 626574 626583.4 626589.6 626585 626587.2 626587.9 626538.4 626537 626533.9 626529.7 626524.9 626532.5 626538.2 626545.8 626543.7 626555.9 626559.7 626561.6 172401 172399.6
172399.6
172412 172412 172401 172401 172399.6
172399.6
172412 172412 172401 172401 172448.6
172441.3
172443.6
172430.7
172427 172437.4
172434.3
172430.4
172424.3
172422.7
172427.5
172419.3
172409.2
172405.6
172420.3
172421.7
172429.2
172431.3
172451 172448.6
172441.3
172443.6
172430.7
172427 172437.4
172434.3
172430.4
172424.3
172422.7
172427.5
34.366 21.336 21.336 21.336 21.336 21.336 21.336 38.366 38.366 38.366 38.366 38.366 38.366 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 37.432 37.432 37.432 37.432 37.432 37.432 37.432 37.432 37.432 37.432 37.432 13 21.336 21.336 21.336 21.336 21.336 21.336 17 17 17 17 17 17 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 27.432 10 10 10 10 10 10 10 10 10 10 10 6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
93 14 14 14 14 14 14 14 14 626577 626574 626583.4 626589.6 626585 626587.2 626587.9 626538.4 172419.3
172409.2
172405.6
172420.3
172421.7
172429.2
172431.3
172451 37.432 37.432 37.432 37.432 37.432 37.432 37.432 37.432 10 10 10 10 10 10 10 10 A.2.2 Receiver Database
1
626538.324
172365.273
27.384
1
626551.353
172378.909
27.384
1
626550.2
172380.5
27.384
1
626546.526
172375.556
27.384
A.2.3 Terrain Elevation Database (Part of te.txt)
5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 19.9972
20.24458
20.49195
20.73933
20.9867
21.23408
21.56355
21.94821
22.31057
22.67293
23.03529
23.39765
23.74756
24.0932
24.41501
24.61649
24.80676
6
6
6
6
6
6
6
6
94 90 95 100 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240 245 250 255 260 265 270 0 5 10 15 20 25 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 205 205 205 205 205 205 24.95694
25.10712
25.2573
25.30105
25.32314
25.34522
25.36731
25.38939
25.41148
25.43357
25.27983
25.12412
24.98731
24.85247
24.73048
24.60743
24.38607
24.0378
23.7813
23.48585
23.26443
23.01358
22.75866
22.60679
22.41428
22.24114
22.08874
21.95576
21.84973
21.68453
21.58013
21.47521
21.39023
21.29604
21.1844
21.07276
20.93484
20.08801
20.22686
20.36571
20.54611
20.79348
21.04086
95 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 205 21.28823
21.64798
22.03365
22.41932
22.80499
23.18638
23.54874
23.9111
24.25726
24.51065
24.71213
24.9136
25.10705
25.25723
25.40741
25.53669
25.55878
25.58086
25.60295
25.62504
25.64712
25.64829
25.49258
25.34265
25.2078
25.07295
25.04112
24.87541
24.65405
24.4327
24.1563
23.86085
23.62668
23.31213
23.12266
22.93833
22.74582
22.57893
22.42653
22.34166
22.2345
22.08222
21.97945
96 245 250 255 260 265 270 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180 205 205 205 205 205 205 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 21.85586
21.77088
21.6859
21.60092
21.51594
21.3942
20.32398
20.46283
20.60168
20.74053
20.87938
21.09501
21.34675
21.73241
22.11808
22.50375
22.88942
23.27509
23.66076
24.04643
24.4048
24.60628
24.80776
25.00924
25.21072
25.40735
25.55753
25.70771
25.79442
25.8165
25.83859
25.86068
25.88276
25.86103
25.70532
25.56314
25.42829
25.35744
25.35176
25.14339
24.92204
24.70445
24.49019
97 185 190 195 200 205 210 215 220 225 230 235 240 245 250 255 260 265 270 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 210 24.23977
23.92522
23.63541
23.46238
23.26986
23.07735
22.91672
22.79269
22.72756
22.61928
22.48188
22.36209
22.2365
22.15152
22.06654
21.98157
21.89048
21.76086
.
.
.
.
.
.
.
.
.
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 25.55879
25.29864
25.03849
24.77834
24.51819
24.38171
24.38171
24.38171
24.38171
24.38171
24.38171
24.38171
24.38171
24.38171
24.38171
24.31806
24.21258
24.1071
24.05735
24.03371
24.01006
98 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240 245 250 255 260 265 270 0 5 10 15 20 25 30 35 40 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 365 370 370 370 370 370 370 370 370 370 23.98642
24.02192
24.11171
24.2015
24.29128
24.38107
24.60336
24.93272
25.26208
25.58604
25.88107
26.17611
26.47114
26.76618
27.06121
27.35625
27.66598
27.98949
28.31299
28.6365
28.96
29.28351
29.60701
29.94352
30.30817
30.48074
30.48074
30.48074
30.48074
30.48074
30.52087
30.73994
30.95901
31.17808
25.68575
25.4256
25.16545
24.9053
24.64515
24.385
24.38171
24.38171
24.38171
99 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 205 210 215 220 225 230 235 240 245 250 255 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 370 24.38171
24.38171
24.38171
24.38171
24.37768
24.20814
24.10266
23.99718
23.8917
23.83777
23.81413
23.79049
23.76684
23.80858
23.89836
23.98815
24.07794
24.16773
24.33358
24.62476
24.95411
25.26267
25.5577
25.85274
26.14777
26.44755
26.75347
27.02097
27.3658
27.6935
28.017
28.34051
28.66401
28.98752
29.31102
29.65872
30.02337
30.38801
30.48074
30.48074
30.48074
30.49905
30.71812
100 260 265 270 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 370 370 370 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 30.93719
31.15626
31.37533
25.81271
25.55256
25.29241
25.03226
24.77211
24.51196
24.38171
24.38171
24.38171
24.38171
24.38171
24.38171
24.37226
24.19107
24.00988
23.88726
23.78177
23.67629
23.6182
23.59455
23.57091
23.54726
23.59523
23.68502
23.77481
23.8646
23.97821
24.16186
24.34551
24.64427
24.9393
25.24078
25.54669
25.85261
26.15853
26.42472
26.70547
27.0503
27.39513
27.72102
101 200 205 210 215 220 225 230 235 240 245 250 255 260 265 270 375 375 375 375 375 375 375 375 375 375 375 375 375 375 375 28.04452
28.36803
28.69153
29.01504
29.37392
29.73857
30.10321
30.46785
30.48074
30.48074
30.69629
30.91537
31.13444
31.35351
31.57258
A.2.4 Antenna Radiation Pattern Database (Part of rd.txt)
H, 0 , 6.30957E‐07 H, 1 , 6.30957E‐07 H, 2 , 6.30957E‐07 H, 3 , 6.30957E‐07 H, 4 , 6.30957E‐07 H, 5 , 6.30957E‐07 H, 6 , 6.30957E‐07 H, 7 , 5.62341E‐07 H, 8 , 5.01187E‐07 H, 9 , 5.01187E‐07 H, 10 , 5.01187E‐07 H, 11 , 4.46684E‐07 H, 12 , 3.98107E‐07 102 H, 13 , 3.54813E‐07 H, 14 , 3.16228E‐07 H, 15 , 2.81838E‐07 H, 16 , 2.51189E‐07 H, 17 , 2.23872E‐07 H, 18 , 1.99526E‐07 H, 19 , 1.77828E‐07 H, 20 , 1.58489E‐07 H, 21 , 1.41254E‐07 H, 22 , 1.25893E‐07 H, 23 , 0.0000001 H, 24 , 7.94328E‐08 H, 25 , 6.30957E‐08 H, 26 , 5.01187E‐08 H, 27 , 4.46684E‐08 H, 28 , 3.98107E‐08 H, 29 , 3.98107E‐08 H, 30 , 3.98107E‐08 H, 31 , 3.54813E‐08 H, 32 , 3.16228E‐08 H, 33 , 2.81838E‐08 H, 34 , 2.51189E‐08 H, 35 , 2.23872E‐08 H, 36 , 1.99526E‐08 H, 37 , 1.77828E‐08 H, 38 , 1.58489E‐08 103 H, 39 , 1.25893E‐08 H, 40 , 0.00000001 H, 41 , 7.94328E‐09 H, 42 , 6.30957E‐09 H, 43 , 5.62341E‐09 H, 44 , 5.01187E‐09 H, 45 , 5.01187E‐09 H, 46 , 5.01187E‐09 H, 47 , 5.62341E‐09 H, 48 , 6.30957E‐09 H, 49 , 6.30957E‐09 H, 50 , 6.30957E‐09 H, 51 , 7.07946E‐09 H, 52 , 7.94328E‐09 H, 53 , 8.91251E‐09 H, 54 , 0.00000001 H, 55 , 0.00000001 H, 56 , 0.00000001 H, 57 , 1.12202E‐08 H, 58 , 1.25893E‐08 H, 59 , 1.25893E‐08 H, 60 , 1.25893E‐08 H, 61 , 1.41254E‐08 H, 62 , 1.58489E‐08 H, 63 , 1.77828E‐08 H, 64 , 1.99526E‐08 104 H, 65 , 1.99526E‐08 H, 66 , 1.99526E‐08 H, 67 , 1.99526E‐08 H, 68 , 1.99526E‐08 H, 69 , 1.99526E‐08 H, 70 , 1.99526E‐08 H, 71 , 1.99526E‐08 H, 72 , 1.99526E‐08 H, 73 , 1.77828E‐08 H, 74 , 1.58489E‐08 H, 75 , 1.41254E‐08 H, 76 , 1.25893E‐08 H, 77 , 1.25893E‐08 H, 78 , 1.25893E‐08 H, 79 , 1.12202E‐08 H, 80 , 0.00000001 H, 81 , 0.00000001 H, 82 , 0.00000001 H, 83 , 0.00000001 H, 84 , 0.00000001 H, 85 , 7.94328E‐09 H, 86 , 6.30957E‐09 H, 87 , 5.62341E‐09 H, 88 , 5.01187E‐09 H, 89 , 5.01187E‐09 H, 90 , 5.01187E‐09 105 H, 91 , 5.01187E‐09 H, 92 , 5.01187E‐09 H, 93 , 5.62341E‐09 H, 94 , 6.30957E‐09 H, 95 , 6.30957E‐09 H, 96 , 6.30957E‐09 H, 97 , 7.07946E‐09 H, 98 , 7.94328E‐09 H, 99 , 7.94328E‐09 H, 100 , 7.94328E‐09 .
.
.
.
.
.
.
.
.
V, 304 , 1.25893E‐09 V, 305 , 1.42889E‐09 V, 306 , 1.62181E‐09 V, 307 , 2.13796E‐09 V, 308 , 2.81838E‐09 V, 309 , 3.23594E‐09 V, 310 , 3.71535E‐09 V, 311 , 4.31519E‐09 V, 312 , 5.01187E‐09 V, 313 , 5.30884E‐09 V, 314 , 5.62341E‐09 V, 315 , 6.30957E‐09 V, 316 , 7.07946E‐09 106 V, 317 , 6.83912E‐09 V, 318 , 6.60693E‐09 V, 319 , 8.12831E‐09 V, 320 , 0.00000001 V, 321 , 8.31764E‐09 V, 322 , 6.91831E‐09 V, 323 , 7.4131E‐09 V, 324 , 7.94328E‐09 V, 325 , 6.30957E‐09 V, 326 , 5.01187E‐09 V, 327 , 4.46684E‐09 V, 328 , 3.98107E‐09 V, 329 , 4.46684E‐09 V, 330 , 5.01187E‐09 V, 331 , 5.62341E‐09 V, 332 , 6.30957E‐09 V, 333 , 7.94328E‐09 V, 334 , 0.00000001 V, 335 , 1.25893E‐08 V, 336 , 1.58489E‐08 V, 337 , 2.23872E‐08 V, 338 , 3.16228E‐08 V, 339 , 6.30957E‐08 V, 340 , 1.25893E‐07 V, 341 , 1.41254E‐07 V, 342 , 1.58489E‐07 107 V, 343 , 1.6788E‐07 V, 344 , 1.77828E‐07 V, 345 , 1.88365E‐07 V, 346 , 1.99526E‐07 V, 347 , 2.23872E‐07 V, 348 , 2.51189E‐07 V, 349 , 2.81838E‐07 V, 350 , 3.16228E‐07 V, 351 , 3.54813E‐07 V, 352 , 3.98107E‐07 V, 353 , 5.01187E‐07 V, 354 , 6.30957E‐07 V, 355 , 6.30957E‐07 V, 356 , 6.30957E‐07 V, 357 , 7.07946E‐07 V, 358 , 7.94328E‐07 V, 359 , 8.91251E‐07 V, 360 , 0.000001 108 A.3
Output of the Prediction Tool
#Start Time: Fri Mar 21 20:49:15 2008 #End Time: Fri Mar 21 20:49:35 2008 #**************************************** #*** INPUT FILES #*** Buildings: BLD0.txt #*** Receivers: rdbb.txt #*** Terrain: te.txt #*** Indoor Features: none #*** Preprocessed Data: none #**************************************** #*** INPUT PARAMETERS #*** Incremental angle 1.000 #*** Number of Reflections 10 #*** Number of Diffractions 2 #*** Prediction Frequency 5805.0MHz #*** Fresnel Width Used n=1.00 #*** Single Ray Model Was Used #*** Transmitter Located at x=626480.0 y=172268.5 z=30.3 #*** Height of Transmitter 12.0 #*** Height of Receivers 3.0 #**************************************** 1 626550.2 172380.5 30.4 ‐80.39 | 0.00e+000 0 6.03e‐009 4 2.99e‐009 9 1.21e‐010 1 | 1.20e‐007 7.34e‐007 109 #Start Time: Sun Mar 23 06:19:25 2008 #End Time: Sun Mar 23 06:19:47 2008 #**************************************** #*** INPUT FILES #*** Buildings: BLD0.txt #*** Receivers: rdbm.txt #*** Terrain: te.txt #*** Indoor Features: none #*** Preprocessed Data: none #**************************************** #*** INPUT PARAMETERS #*** Incremental angle 1.000 #*** Number of Reflections 10 #*** Number of Diffractions 2 #*** Prediction Frequency 5805.0MHz #*** Fresnel Width Used n=1.00 #*** Single Ray Model Was Used #*** Transmitter Located at x=626480.0 y=172268.5 z=30.3 #*** Height of Transmitter 12.0 #*** Height of Receivers 3.0 #**************************************** 1 626538.3 172365.3 30.4 ‐54.83 | 3.29e‐006 1 0.00e+000 0 0.00e+000 0 0.00e+000 0 | 6.80e‐011 3.79e‐007 110 #Start Time: Thu Mar 13 00:20:34 2008 #End Time: Thu Mar 13 00:20:55 2008 #**************************************** #*** INPUT FILES #*** Buildings: BLD0.txt #*** Receivers: rdb0.txt #*** Terrain: te.txt #*** Indoor Features: none #*** Preprocessed Data: none #**************************************** #*** INPUT PARAMETERS #*** Incremental angle 1.000 #*** Number of Reflections 10 #*** Number of Diffractions 2 #*** Prediction Frequency 5805.0MHz #*** Fresnel Width Used n=1.00 #*** Single Ray Model Was Used #*** Transmitter Located at x=626480.0 y=172268.5 z=30.3 #*** Height of Transmitter 12.0 #*** Height of Receivers 3.0 #**************************************** 1 626551.4 172378.9 30.4 ‐81.63 | 0.00e+000 0 5.61e‐009 4 1.26e‐009 5 0.00e+000 0 | 7.97e‐008 7.34e‐007 111 #Start Time: Fri Mar 21 09:44:41 2008 #End Time: Fri Mar 21 09:45:02 2008 #**************************************** #*** INPUT FILES #*** Buildings: BLD0.txt #*** Receivers: rdb1.txt #*** Terrain: te.txt #*** Indoor Features: none #*** Preprocessed Data: none #**************************************** #*** INPUT PARAMETERS #*** Incremental angle 1.000 #*** Number of Reflections 10 #*** Number of Diffractions 2 #*** Prediction Frequency 5805.0MHz #*** Fresnel Width Used n=1.00 #*** Single Ray Model Was Used #*** Transmitter Located at x=626480.0 y=172268.5 z=30.3 #*** Height of Transmitter 12.0 #*** Height of Receivers 3.0 #**************************************** 1 626550.8 172377.9 30.4 ‐81.13 | 0.00e+000 0 6.34e‐009 5 1.36e‐009 7 0.00e+000 0 | 4.86e‐008 7.52e‐007 112 #Start Time: Mon Mar 24 11:07:20 2008 #End Time: Mon Mar 24 11:07:41 2008 #**************************************** #*** INPUT FILES #*** Buildings: BLD0.txt #*** Receivers: rdbm.txt #*** Terrain: te.txt #*** Indoor Features: none #*** Preprocessed Data: none #**************************************** #*** INPUT PARAMETERS #*** Incremental angle 1.000 #*** Number of Reflections 10 #*** Number of Diffractions 2 #*** Prediction Frequency 5805.0MHz #*** Fresnel Width Used n=1.00 #*** Single Ray Model Was Used #*** Transmitter Located at x=626480.0 y=172268.5 z=30.3 #*** Height of Transmitter 12.0 #*** Height of Receivers 3.0 #**************************************** 1 626538.3 172365.3 30.4 1.03 4.17 0.104986 113.60 3.79e‐007 ‐54.83 ‐1 113 A.4
VPL Ray Tracing Visualization Code
disp('++++++++++++++++++++++++++++++++++++++++++++++++++++++++++')
disp('
VPL Ray Tracing Visualization
')
disp('
Copyright (c) 2003, 2004 by
')
disp('
Wireless Communication Centre (WCC) ')
disp('++++++++++++++++++++++++++++++++++++++++++++++++++++++++++')
disp('
')
disp('
')
disp('************************* Program is running.********************* **')
bd=input('Please insert a building database filename: ','s');
te=input('Please insert a terrain database filename: ','s');
name=input('Please insert simulation result filename: ','s');
startno=input('Ray trace at receiver number (start) : ','s');
stopno=input('Ray trace at receiver number (end) : ','s');
freq=input('Please insert frequency used [MHz] during simulation (eg:2000) :','s');
file1=fopen(bd,'r');
file2=fopen('M_build.txt','w');
build=fscanf(file1,'%d %f %f %f %f %*d \n')';
fprintf(file2,'%d %f %f %f %f \n',build);
build=[reshape(build,5,[])]';
fclose(file1);
fclose(file2);
figure;
hold on
file5=fopen(te,'r');
te=fscanf(file5,'%f %f %f \n')';
te=[reshape(te,3,[])]';
[Y,X] = meshgrid(0:5:370,0:5:270);
Z = te(:,3);
114 Z=[reshape(Z,55,[])];
[C,h] = contour3(X,Y,Z,30);
hold on;
surface(X,Y,Z,'EdgeColor',[.5 .5 .5],'FaceColor','interp','CDataMapping','direct')
hold on;
colormap summer
fclose(file5);
xlabel('x-coordinat (meter)')
ylabel('y-coordinat (meter)')
title('Ray Path Tracing','FontSize',16)
set(gca,'color','w','xcolor','k','ycolor','k')
set(get(gca,'title'),'color',[1 0 0])
set(get(gca,'xlabel'),'color',[0 0 1])
set(get(gca,'ylabel'),'color',[0 0 1])
set(get(gca,'zlabel'),'color',[0 0 1])
set(gcf,'color','w')
data=[name,'_tx1_',freq,'MHz'];
file5=fopen(data,'rt');
file6=fopen('M_rxpoint.txt','w');
status=fseek(file5,698,-1);
result=fscanf(file5,'%d %f %f %f %*4d %*s %*s %*4d %*s %*d %*4d %*s %*d
%*4d %*s %*d %*4d %*s %*d%*s %*4d %*s %*4d %*s\n')';
fprintf(file6,'%d %f %f %f \n',result);
result=[reshape(result,4,[])]';
fclose(file5);
fclose(file6);
% read location of transmitter %
data=[name,'_tx1_',freq,'MHz'];
file3=fopen(data,'rt');
status=fseek(file3,494,-1);
115 Xt=fscanf(file3,'%*4s %*11s %*7s %*2s %f');
status=fseek(file3,494,-1);
Yt=fscanf(file3,'%*4s %*11s %*7s %*2s %*f %*2s %f');
status=fseek(file3,494,-1);
Zt=fscanf(file3,'%*4s %*11s %*7s %*2s %*f %*2s %*f %*2s %f');
status=fseek(file3,550,-1);
height=fscanf(file3,'%*4s %*11s %*7s %*2s %*f %*2s %*f %*2s %*f\n %*4s %*6s
%*2s %*11s %f');
fclose(file3);
plot3(Xt,Yt,Zt,'*b')
hold on;
plot3([Xt Xt],[Yt Yt],[Zt Zt+height],'-g*','LineWidth',1,'MarkerEdgeColor',[0 0
0],'MarkerFaceColor',[0 0 0])
hold on;
legend('Receiver Point','Transmitter',4);
plot3([ Xt Xt],[ Yt Yt],[Zt Zt+height],'-g','LineWidth',5);
hold on;
plot3(Xt,Yt,Zt,'*k')
hold on;
plot3(Xt,Yt,Zt+height,'*k')
hold on;
% building drawing %
n=length(build);
i=1;
m=0;
while i<=n-1
if build(i+1,1)==build(i,1)
xa=[build(i,2) build(i,2) build(i+1,2) build(i+1,2)];
ya=[build(i,3) build(i,3) build(i+1,3) build(i+1,3)];
116 za=[build(i,4)-build(i,5) build(i,4) build(i+1,4) build(i+1,4)-build(i+1,5)];
fill3(xa,ya,za,'y')
hold on;
m=m+1;
else
xa=[build(i,2) build(i,2) build(i-m,2) build(i-m,2)];
ya=[build(i,3) build(i,3) build(i-m,3) build(i-m,3)];
za=[build(i,4)-build(i,5) build(i,4) build(i-m,4) build(i-m,4)-build(i-m,5) ];
fill3(xa,ya,za,'y')
hold on;
xb=build(i-m:i,2);
yb=[build(i-m:i,3)];
zb=[build(i-m:i,4)-build(i-m:i,5)];
fill3(xb,yb,zb,'y')
hold on;
xc=build(i-m:i,2);
yc=[build(i-m:i,3)];
zc=[build(i-m:i,4)];
fill3(xc,yc,zc,'r')
hold on;
m=0;
end
i=i+1;
end
xa=[build(i,2) build(i,2) build(i-m,2) build(i-m,2)];
ya=[build(i,3) build(i,3) build(i-m,3) build(i-m,3)];
za=[build(i,4)-build(i,5) build(i,4) build(i-m,4) build(i-m,4)-build(i-m,5) ];
fill3(xa,ya,za,'y')
xb=build(i-m:i,2);
yb=[build(i-m:i,3)];
zb=[build(i-m:i,4)-build(i-m:i,5)];
117 fill3(xb,yb,zb,'y')
xc=build(i-m:i,2);
yc=[build(i-m:i,3)];
zc=[build(i-m:i,4)];
fill3(xc,yc,zc,'y')
% ray tracing visualization %
startno=strread(startno,'%u');
stopno=strread(stopno,'%u');
num=startno;
while num<=stopno
number=int2str(num);
file4=fopen('M_ray_edit.txt','w');
rayfile=['C:\TL\ray_paths_tx1_rx',number,'_',freq,'MHz'];
[x,y,z]=textread(rayfile,'%f %f %f','whitespace','\n','commentstyle','shell');
ray=[x,y,z];
fprintf(file4,'%f %f %f \n',ray);
fclose(file4);
plot3(result(num,2),result(num,3),result(num,4),'*b');
n=length(ray);
i=2;
while i<=n
if i==n
plot3([ray(i,1) ray(i-1,1)],[ray(i,2) ray(i-1,2)],[ray(i,3) ray(i-1,3)],'r');
plot3([ray(i,1) result(num,2)],[ray(i,2) result(num,3)],[ray(i,3) result(num,4)],'r');
i=i+1;
elseif n==3&i==2
plot3([ray(i,1) ray(i-1,1)],[ray(i,2) ray(i-1,2)],[ray(i,3) ray(i-1,3)],'r');
plot3([ray(i,1) result(num,2)],[ray(i,2) result(num,3)],[ray(i,3) result(num,4)],'r');
i=i+2;
elseif ray(i,1)==ray(1,1)&ray(i,2)==ray(1,2)&ray(i,3)==ray(1,3)
118 plot3([ray(i-1,1) result(num,2)],[ray(i-1,2) result(num,3)],[ray(i-1,3)
result(num,4)],'r');
i=i+1;
else
plot3([ray(i,1) ray(i-1,1)],[ray(i,2) ray(i-1,2)],[ray(i,3) ray(i-1,3)],'r');
i=i+1;
end
end
num=num+1;
end
hold off
disp('************************* Ray Visualized Successfully.******** ********')
119 Appendix B
TEST OF WIRELESS SYSTEM
B.1
Configuration of MikroTik PC Router
Interface Setting
[admin@MikroTik] interface> print
Flags: X - disabled, D - dynamic, R - running
NAME TYPE MTU
o X etherl ether 1500
0 X ether2 ether 1500
[admin@MikroTik] interface> enable 0
[admin@MikroTik] interface> enable ether2
[admin@MikroTik] interface> print
Flags: X - disabled, D - dynamic, R - running
NAME
TYPE
MTU
0 R etherl
ether
1500
0 R ether2
ether
1500
[admin@MikroTik] interface>
120 Interfaces can be enabled by using the name or number of the interface in the enable
command. The interface name can be changed to a more descriptive one by using the
`/interface set' command:
[admin@MikroTik] interface> set 0 name-isp
[admin@MikroTik] interface> set 1 name=internet
[admin@MikroTik] interface> print
Flags: X - disabled, D - dynamic, R - running
# NAME
TYPE
MTU
0 R isp
ether
1500
0 R internet
ether
1500
[admin@MikroTik] interface>
IP Setting
The addresses can be added and viewed using the following commands:
[admin@MikroTik] ip address> add address 10.6.3.252/23 interface isp
[admin@MikroTik] ip address> add address 10.1.2.254/24 interface Internet
[admin@MikroTik] ip address> print
Flags: X - disabled, I - invalid, D
dynamic
# ADDRESS
NETWORK BROADCASTINTERFACE
0 10.6.3.252/23
10.6.3.0
10.6.3.255
1 10.1.2.254/24
10.1.2.0
10.1.2.255
isp
Internet
[admin@MikroTik] ip address>
IP Route Setting
Two dynamic (D) and connected (C) routes will appear, which have been added
121 automatically when the addresses were added in the above procedure:
[admin@MikroTik] ip route> print
Flags: X - disabled, I - invalid, D - dynamic, J - rejected,
C - connect, S - static, R - rip, 0 - ospf, B - bgp
# DST-ADDRESS
G GATEWAY
DISTANCE
INTERFACE
0 DC 10.1.2.0/24
r 0.0.0.0
0
Internet
1 DC 10.6.3.0/23
r 0.0.0.0
0
isp
[admin@MikroTik] ip route> print detail
Flags: X - disabled, I - invalid, D - dynamic, J - rejected,
C - connect, S - static, R - rip, 0 - ospf, B - bgp
0 DC dst-address=10.1.2.0/24 preferred-source=10.1.2.254
gateway=0.0.0.0 gateway-state-reachable distance-0 interface=internet
1 DC dst-address-10.6.3.0/23 preferred-source=10.6.3.252 gateway=0.0.0.0
gateway-state=reachable distance=0 interface=isp
[admin@MikroTik] ip route>
These routes show that IP packets with destination to 10.6.3.0/23 would be sent
through the interface isp', whereas IP packets with destination to 10.1.2.0/24 would be
sent through the interface `internet'. However, you need to specify where the router
should forward packets, which have destination other than networks connected
directly to the router.
In the following command the default route (destination 0.0.0.0, netmask
0.0.0.0) will be added. In this case it is the ISP's gateway 10.6.3.252 which can
be reached through the interface `isp':
admin@MikroTik] ip route> add gateway=10.6.3.250
[admin@MikroTik] ip route> print
Flags: X - disabled, I - invalid, D - dynamic, J - rejected,
122 C - connect, S - static, R - rip, 0 - ospf, B - bgp
# DST-ADDRESS
0S
0.0.0.0/0
G GATEWAY
DISTANCE
INTERFACE
r 10.6.3.250
1
isp
1 DC
10.1.2.0/24
r 0.0.0.0
0
internet
2 DC
10.6.3.0/23
r 0.0.0.0
0
isp
[admin@MikroTik] ip route>
The default route is listed under #0. As we see, the gateway 10.6.3.250 can be
reached through the interface `isp'. If the gateway was specified incorrectly, the value
for the argument 'interface' would be unknown.
Connectivity Testing
From now on, the `/ping' command can be used to test the network connectivity
on both interfaces. Any host on both connected networks can be reach from the router.
[admin@MikroTik] ip route> /ping 10.6.3.250
10.6.3.250 64 byte pong: tt1=255 time=7 ms
10.6.3.250 64 byte pong: tt1=255 time=5 ms
10.6.3.250 64 byte pong: tt1=255 time=5 ms
3 packets transmitted, 3 packets received, 0% packet loss
round-trip min/avg/max = 5/5.6/7 ms
[admin@MikroTIk] ip route>
[admin@MikroTik] ip route> /ping 10.1.2.250
10.1.2.250 64 byte pong: tt1=255 time<1 ms
10.1.2.250 64 byte pong: tt1=255 time<1 ms
10.1.2.250 64 byte pong: tt1=255 time<1 ms
3 packets transmitted, 3 packets received, 0% packet loss
round-trip min/avg/max = 0/0.0/0 ms
[admin@MikroTik] ip route>
123 The monitoring PC can reach (ping) the router at its local address 10.1.2.0/24, if
the router's address 10.1.2.254/24 is specified as the default gateway in the TCP/IP
configuration.
C :\ > ping 10 .1 .2. 250
Reply from 10. 1.2 .250 : bytes = 32 time = 10 ms TTL 253
Reply from 10. 1.2 .250 : bytes = 32 time = 10 ms TTL 253
Reply from 10. 1.2 .250 : bytes = 32 time = 10 ms TTL 253
C :\> ping 10.6.3.250
Request timed out.
Request timed out.
Request timed out.
Beyond the router (network 10.6.3.0/23 and the 'interne' interface) are not
accessible, unless you do the following [16]:
Use source network address translation (masquerading) on the MikroTik router to
'hide' your private LAN 10.1.2.0/24 (see the information below), or
Add a static route on the ISP's gateway 10.6.3.250, which specifies the host
10.6.3.252 as the gateway to network 10.1.2.0/24. Then all hosts on the ISP's
network, including the server, will be able to communicate with the hosts on the LAN.
Next will be discussed situation with 'hiding' the private LAN 10.1.2.0/24
'behind' one address 10.6.3.252 given to the interface `isp'.
124 Masquerading
To 'hide' the private LAN 10.1.2.0/24 'behind' one address 10.6,3.252 given by
the ISP, use the source network address translation (masquerading) feature of the
MikroTik router. Masquerading is useful, if you want to access the ISP's network and
the Internet appearing as all requests coming from the host 10.6.3.252 of the ISP's
network. The masquerading will change the source IP address and port of the packets
originated from the network 10.1.2.0/24 to the address 10.6.3.252 of the router when the
packet is routed through it.
Masquerading conserves the number of global IP addresses required and it lets
the whole network use a single IP address in its communication with the world. To use
masquerading, a source NAT rule with action 'masquerade' should be added to the
firewall configuration:
admin@MikroTik] ip firewall src-nat> add action=masquerade out-interface=isp
[admin@MikroTik] ip firewall src-nat> print
Flags: X - disabled, I - invalid, D - dynamic
0 src-address=0.0.0.0/0:0-65535 dst-address=0.0.0.0/0:0-65535
out-interface=isp protocol=all icmp-options=any:any flow=""
limit-count=0 limit-burst=0 limit-time=Os action=masquerade
to-src-address=0.0.0.0 to-src-port=0-65535
[admin@MikroTik] ip firewall src-nat>
125 DHCP Client Setup
The MikroTik RouterOS DHCP client may be enabled on one Ethernet—like
interface. The client will accept an address, netmask, default gateway, and two dns
server addresses. The IP address will be added to the interface with the netmask. The
default gateway will be added to the routing table as a dynamic entry. When the DHCP
client is disabled, the dynamic default route will be removed. If there is already a
default route installed prior the DHCP client obtains one, the route obtained by the
DHCP client would be shown as invalid.
The DNS-server from the DHCP server will be used as the router's default
DNS if the router's DNS is set to 0.0.0.0 under the Yip dns' settings.
To enable DHCP client on `isp' interface:
[admin@MikroTik] ip dhcp-client> set enabled-yes interface=isp
[admin@MikroTik] ip dhcp-client> print
enabled: yes interface: isp host-name: "" client-id: "" add-default-route: yes
use-peer-dns: yes
To show obtained leases:
[admin@MikroTik] ip dhcp-client> lease print address: 10.1.2.0/24
expires: oct/20/2002 09:43:50
gateway: 10.1.2.254
primary-dns: 161.139.250.2
secondary-dns: 161.139.16.2
[admin@MikroTik] ip dhcp-client>
126 DHCP Server Setup
The router supports an individual server for each Ethernet like interface. The
MikroTik RouterOS DHCP server supports the basic functions of giving each
requesting client an IP address/netmask lease, default gateway, domain name, DNSserver(s) and WINS-server(s) (for Windows clients) information. Specify address
pool to be used for DHCP clients in order to use MikroTik RouterOS DHCP server
feature. Address pools are added/managed under the Yip pool' menu.
[admin@MikroTik] ip pool> add name=pooll ranges=10.1.2.2-10.1.2.200
[admin@MikroTik] ip pool> print
NAME
0 pooll
RANGES
10.1.2.2-10.1.2.200
[admin@MikroTik] ip pool>
Do not inlude the DHCP server's (interface's) address into the pool range!
Add a DHCP server to the interface:
[admin@MikroTik] ip dhcp-server> add name=dhcppooll \
\... address-pool=pooll interface=internet lease-time=72h netmask=23 \
\... gateway=10.1.2.254 dns-server=161.139.250.2, 161.139.16.2 domain=mt.lv
[admin@MikroTik] ip dhcp-server> enable dhcppooll
[admin@MikroTik] ip dhcp-server> print
Flags: X - disabled, I - invalid
0 name="dhcppooll" interface=internet lease-time=72h
address-pool=pooll netmask=23 gateway=10.1.2.254
src-address=10.1.2.254 dns-server=161.139.250.2, 161.139.16.2 domain="mt.lv"
wins-server="" add-arp=yes
[admin@MikroTik] ip dhcp-server>
127 B.2
Configuration of MikroTik Radio Unit #1
Ethernet port of MikroTik Router #1 is connected to DHCP server through a
switch. Therefore Ether port will be given an IP address range from 10.1.2.210.1.2.200, as specified in `pool/'.
Wireless Interface Configuration
Atheros 5G/ABM Wireless adapter is a new generation solution for wireless
applications. This universal Multi-Band (2.4 GHz, 5.2 GHz, 5.8 GHz) PCI operates in
any existing IEEE wireless standard. It minimizes any potential confusion or
incompatibilities caused by having three separate wireless devices. The Multi-Band
Wireless PCI operates in both 2.4 GHz and 5 GHz wireless bands The MikroTik
RouterOS supports as many Atheros chipset based cards as many free resources are
there on your system. MikroTik router is connected to an AP using Atheros card and
the AP is operating in IEEE 802.11b standard with ssid=PtP.
The following command should be issued to change the settings for the wireless AP
interface:
[admin@MikroTik] interface wireless> print
Flags: X - disabled, R - running
0 X name="wlanl" mtu=1500 mac-address=00:01:24:70:03:75 arp=enabled
card-type=Atheros AR5211 2.4/5 GHz mode-station ssid="MikroTik"
frequency=5180 band=5GHz scan-list=default-ism
supported-rates-a=6Mbps,9Mbps,12Mbps,18Mbps,24Mbps,36Mbps,48Mbps,54Mbps
basic-rates-a=6Mbps supported-rates-b=1Mbps,2Mbps,5.5Mbps,11Mbps
basic-rates-b=lMbps ack-timeout=default tx-power=default default-key-0=""
default-key-l="" default-key-2="" default-key-3="" station-private-key=""
128 transmit-key-id=0 encryption=none used-authentication=open-system
accepted-authentication=open-system default-authentication=yes
default-forwarding=yes 802.1x-enable=no
[admin@MikroTik] interface wireless> set 0 mode=ap-bridge frequency=5785MHz
ssid=PtP; enable 0
[admin@MikroTik] interface wireless> print
Flags: X - disabled, R - running
0 R name="pointopint" mtu=1500 mac-address=00:01:24:70:03:75 arp=enabled
card-type-Atheros AR5213 2.4/5 GHz mode=ap-bridge ssid="PtP"
frequency=5785 band=5GHz scan-list-default-ism
supported-rates-a=6Mbps,9Mbps,12Mbps,18Mbps,24Mbps,36Mbps,48Mbps,54Mbps
basic-rates-a-6Mbps supported-rates-b-1Mbps,2Mbps,5.5Mbps,11Mbps
basic-rates-b-1Mbps ack-timeout=default tx-power=default
default-key-0="" default-key-1-"" default-key-2="" default-key-3=""
station-private-key="" transmit-key-id=0 encryption=none
used-authentication=open-system accepted-authentication=open-system
default-authentication=yes default-forwarding=yes 802.1x-enable-no
[admin@MikroTik] interface wireless>
Interfaces Setting
By default there are 2 interfaces available which is wlanl and etherl.
Enable both intetrfaces by using commands below:
[admin@MikroTik] interface> print
Flags: X - disabled, D - dynamic,
R – running
# NAME
TYPE
MTU
0 X etherl
ethernet
1500
1 X wlanl
wireless (Atheros AR5213)
1500
129 [admin@MikroTik] interface> enable 0
[admin@MikroTik] interface> enable wlanl
[admin@MikroTik] interface> print
Flags: X - disabled, D - dynamic,
R - running
# NAME
TYPE
MTU
0 R etherl
ethernet
1500
1 R wlanl
wireless(Atheros AR5213)
1500
2 R *wdsl
WDS
1500
[admin@MikroTik] interface>
*wdsl available only after wireless client interfaces has been set to station mode
The interface name can be changed to a more descriptive one by using the `/interface
set' command:
[admin@MikroTik] interface> set 0 name=etherl
[admin@MikroTik] interface> set 1 name=pointopoint
[admin@MikroTik] interface> print
Flags: X - disabled, D - dynamic, R - running
# NAME
TYPE
MTU
0 R etherl
ether
1500
1 R pointopoint
wireless (Atheros AR5213)
[admin@MikroTik] interface>
1500
130 IP Setting
After the both interfaces have been enabled, then IP address can be imposed
to it. Dynamic IP will be assigned by DHCP server to 'etherl’.
[admin@MikroTik] ip address> add address 10.1.1.254/24 interface pointopoint
[admin@MikroTik] ip address> print
Flags: X - disabled, I - invalid, D - dynamic
ADDRESS
NETWORK BROADCAST
INTERFACE
0 D 10.1.2.197/24
10.1.2.0
10.1.2.255
etherl
1
10.1.1.0
10.1.1.255
pointopoint
10.1.1.254/24
[admin@MikroTik] ip address>
IP Route Setting
Connected routes are created automatically when adding address to an interface.
These routes specify networks, which can be accessed directly through the interface
such as route #2 and #3. Static routes are users-defined routes that specify the router
that can forward traffic to the specified network. They are useful for specifying the
default gateway as route #1 and #2.
[admin@MikroTik] ip route> add dst-address=192.168.0.0/24 gateway=10.1.1.252
[admin@MikroTik] ip route> add gateway 10.1.2.254
[admin@MikroTik] ip route> print
Flags: X - disabled, I - invalid, D - dynamic, J - rejected,
C - connect, S - static, r - rip, o - ospf, b - bgp
#
DST-ADDRESS
G GATEWAY
DISTANCE
INTERFACE
0 AS
192.168.0.0/16
r 10.1.1.252
0
pointopoint
1 DA
0.0.0.0/0
r 10.1.2.254
0
etherl
131 2 DAC 10.1.1.0/24
r 0.0.0.0
0
pointopoint
3 DAC 10.1.2.0/24
r 0.0.0.0
0
etherl
Bridge Interface Setup
Ethernet—like networks (Ethernet, Ethernet over IP, IEEE802.1 1 Wireless
interfaces in AP mode) can be connected together using MAC Bridges. The bridge
feature allows the interconnection of stations connected to separate LANs (using EolP,
geographically distributed networks can be bridged as well if any kind of IP network
interconnection exists between them) as if they were attached to a single LAN. As
bridges are transparent, they do not appear in trace route list, and no utility can make a
distinction between a host working in one LAN and a host working in another LAN if
these LANs are bridged (depending on the way the LANs are interconnected, latency
and data rate between hosts may vary).
To bridge a number of networks into one bridge, a bridge interface should be
created, that will group all the bridged interfaces. One MAC address will be assigned to
all the bridged interfaces. Note that you may only assign IP addresses to the bridge
interface (the one is created in this submenu level), not the bridged interfaces (the ones
which will be grouped in the bridge).
To add and enable a bridge interface that will forward all the protocols:
[admin@MikroTik] interface bridge> add
[admin@MikroTik] interface bridge> print
Flags: X - disabled, R - running
1 X name="bridgel" mtu=1500 arp=enabled mac-address=00:00:00:00:00:00
forward-protocols=ip,arp,appletalk,ipx,ipv6,other priority=l
[admin@MikroTik] interface bridge> enable 0
132 Port Setting
Interface bridge port is used to group interfaces in a particular bridge interface.
To group `pointopoint' and `wdsl' in the 'bridge l' bridge:
[admin@MikroTik] interface bridge port> set pointopoint, wdsl bridge=bridgel
[admin@MikroTik] interface bridge port> print
Flags: X - disabled
# INTERFACE
BRIDGE
0 pointopoint
bridgel
1 etherl
none
2 *wdsl
bridgel
[admin@MikroTik] interface bridge port>
*wdsl available only after wireless client interfaces has been set to station mode
When configuring the bridge setting, each protocol that should be forwarded should be
Figure B1: Configuration of MikroTik Unit#1 in Win Box
133 Figure B2: Example Bridge reads values
134 Appendix C
Topographical Maps
C.1
UTM Map with Contour Lines Illustrated
Figure C.1: UTM Topographical Map with Contour Lines
135 C.2
UTM Contour map Creating Illustration
Figure C.2: UTM Contour map Building by Auto cad
Figure C.3: UTM Contour map combined with the Original image
136 Figure C.4: The UTM Topographical Image