Laboratory Manual
Telecommunication Engineering
2013 - 2018
TELECOMMUNICATION LABORATORY
ELECTRICAL ENGINEERING DEPARTMENT, FACULTY OF ENGINEERING,
UNIVERSITY OF INDONESIA
KampusBaru UI Depok 16424 Phone : +62-21-7270078 ext.131
TELECOMMUNICATION LABORATORY
ELECTRICAL ENGINEERING DEPARTMENT
FACULTY OF ENGINEERING, UNIVERSITAS INDONESIA
Kampus Baru UI Depok 16424 Telp. 7270078 ext.131, Fax 7270050
Redaction Team
Supervisor
: Dr. Fitri Yuli Zulkifli, S.T.MSc.
Editor
: Aisyah
Author
: Adhitya Satria Pratama
Sarah Karimah
Desta Rianto
Nurul Muhtadin
Ina Gustiana
Sayid Hasan
Budiman Budhiardianto
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TELECOMMUNICATION LABORATORY
ELECTRICAL ENGINEERING DEPARTMENT
FACULTY OF ENGINEERING, UNIVERSITAS INDONESIA
Kampus Baru UI Depok 16424 Telp. 7270078 ext.131, Fax 7270050
TABLE OF CONTENT
I.
Vision and Mission of the Department ............................................................ 2
II. GENERAL LABORATORY GUIDELINES .................................................. 3
III.
PRACTICAL/LABORATORY WORK AND MODULES ........................ 4
1.
TRANSMISSION LINE ...............................................................................4
2.
ANALOG MODULATION ....................................................................... 13
3.
DIGITAL MODULATION ....................................................................... 26
4.
TELEPHONY SYSTEM, PCM, AND TDM ............................................ 33
5.
FIR FILTER USING DSK TMS320C671................................................ 41
6.
RADIO LINES USING RADIO MOBILE SOFTWARE AND MINILINKTM DEVICES ................................................................................. 49
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TELECOMMUNICATION LABORATORY
ELECTRICAL ENGINEERING DEPARTMENT
FACULTY OF ENGINEERING, UNIVERSITAS INDONESIA
Kampus Baru UI Depok 16424 Telp. 7270078 ext.131, Fax 7270050
I. VISION AND MISSION OF THE DEPARTMENT
Vision
The department has the vision to become a high standard of excellence in
education and research in the field of electrical engineering
Missions
In order to achieve such vision, the department has defined its mission to
produce Electrical Engineer graduates who are able to compete beyond the
national labor market
The graduates will capable to respond to the vast growing engineering
technology development through the support of excellent educational process,
excellent management, and organization, international standard of competence
of the teaching staff and international reputation in specific research activities.
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TELECOMMUNICATION LABORATORY
ELECTRICAL ENGINEERING DEPARTMENT
FACULTY OF ENGINEERING, UNIVERSITAS INDONESIA
Kampus Baru UI Depok 16424 Telp. 7270078 ext.131, Fax 7270050
II. GENERAL LABORATORY GUIDELINES
This laboratory manual has evolved over the years to meet the needs of
students taking Telecommunication Engineering at the Electrical Engineering
Department, Faculty of Engineering, University of Indonesia. The intention is
to provide the student with an organized, user-friendly tool to better enable
him or her to understand laboratory aspects of telecommunication engineering
as well as to hopefully make learning laboratory material and preparing for lab
activity a bit easier.
Each lab practical module is set up as a complete module that
demonstrates some basic telecommunication engineering principle or
technique. In this manual, nine practical are included. Each module includes
the objectives, basic theory, equipments needed, and step-by-step procedure
that provides all the information needed to understand that lab. Finally, each
lab module ends with a set of questions form that tells the student exactly what
he or she gets on the lab activity.
The lab module are designed to give the student "hands-on" laboratory
experience to better reinforce certain topics discussed in lecture as well as to
present a number of selected telecommunication engineering principles not
covered in lecture.
Practitioners must follow whole series of Telecommunication Engineering
Lab consisting of six practical modules. Practitioners must prepare lab
materials, through lab module, course materials, and other related sources.
Each practitioner must do and collect the Preliminary Task before the
laboratory activities begin. The time late that can be tolerated is 15 minutes. If
practitioners late more than 15 minuters without any reasonable cause, they
cannot join the laboratory activity on that module. If the practitioners do not
follow the laboratory activity, they would have grade 0 on that module. At the
end of the activity, practitioners must answer the questions and problems from
the practical sheet base on the experiment. We hope you can utilize this
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TELECOMMUNICATION LABORATORY
ELECTRICAL ENGINEERING DEPARTMENT
FACULTY OF ENGINEERING, UNIVERSITAS INDONESIA
Kampus Baru UI Depok 16424 Telp. 7270078 ext.131, Fax 7270050
laboratory manual and also hope it makes your study of telecommunication
engineering easier.
III.
PRACTICAL/LABORATORY WORK AND MODULES
1. TRANSMISSION LINE
In this assignment the measurement of voltage standing wave (vswr) of
waveguide components is undertaken using a waveguide slotted-line and probe
detector. Voltage standing wave ratio, invariably abbreviated to vswr, is one of
the fundamental parameters used in specifying component performance. It
quantifies the degree of mismatch a component presents to the waveguide feed
line.
The concept of impedance in waveguides and the use of the Smith Chart
in impedance and matching calculations are introduced. The measurement of
impedance of a waveguide component is carried out and the results used to
determine the position of a capacitative probe to effect matching.
1.1 Objectives
1. Understand the concept of Voltage Standing Wave Ratio in the
transmission line;
2. Understand the concept of impedance and admittance in the transmission
line
3. Understand how to use Smith Chart to determine the value of impedance
and admittance in the transmission line.
Theory
Energy moves along the transmission line as electromagnetic wave. The wave
generated by the signal source and flows in a transmission line to load is called as
incident wave. If the value of the load impedance, ZL , is equal to the value of the
characteristic impedance of the transmission line, Z0 , then all the energy comes
from the source will be absorbed by the load. In other words, if the transmission
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line with finite length terminated with load impedanceZL = Z0 , then for
the incident wave, line will appear as a line with an infinite length, because at all
points, including at the load terminal, the ratio between the voltage and current
will be equal to𝑍𝑂 . If the load impedance is not equal to the characteristic
impedance of the line, there is energy reflected back toward the source and called
as reflected wave. In Figure 1.1 is shown a picture of a transmission line
terminated by load.
Figure 7.1. A transmission line terminated by load
These reflected waves set up standing wave patterns in the transmission lineas
illustrated in figure 1.2.
Figure 7.2 standing wave
The ratio of maximum and minimum voltage amplitude on a standing wave called
as Voltage Standing Wave Ratio (VSWR) and defined as:
𝑉𝑆𝑊𝑅 =
𝑒𝑚𝑎𝑥
𝑒𝑚𝑖𝑛
…. (1.1)
If the electric field is probed with a diode detector at low power levels, the diode
detector will obey a square law. That is, the current measured in the diode detector
will be proportional to the square of the electric field being probed so that:
𝑖 = 𝑘𝑒 2
…. (1.2)
where k is a constant of proportionality.
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𝑖𝑚𝑎𝑥 𝑘𝑒𝑚𝑎𝑥 2
=
= 𝑉𝑆𝑊𝑅 2
𝑖𝑚𝑖𝑛
𝑘𝑒𝑚𝑖𝑛 2
𝑖
𝑉𝑆𝑊𝑅 = √ 𝑖𝑚𝑎𝑥
.... (1.3)
𝑚𝑖𝑛
The corresponding waveguide reflection coefficient is
𝑉𝑆𝑊𝑅−1
𝛤 = 𝑉𝑆𝑊𝑅+1
…. (1.4)
The waveguide return loss (in dB) is defined as
…. (1.5)
There are two ways in determining the value of VSWR, namely:
1. Direct Methods
By measuring the current values along the transmission line, the results of these
measurements will obtain current value at each point in the transmission line,
VSWR graphs can be drawn by plotting each value of current at any point in the
transmission line.
2. Indirect method (Double minimum method)
Indirect method is used to improve the direct method if the value of VSWR more
than 10.
Reflected waves indicate that the load impedance does not match to the
line impedance.This causes the calculation of the amount of transmission becomes
complicated. To simplify the calculations, we use Smith Chart. Smith Chart is a
diagram
used
to
understand
the
characteristics
of
transmission
lines
and microwave circuit elements. This diagram consists of real and imaginary
component, in which the real component is shown by full circles, while the
imaginary component is shown by the curved shape. Some characteristics of
transmission line can be calculated by the Smith Chart, such as VSWR, load
impedance, load admittance and reflection coefficient. From the Smith Chart, it
can be determined whether the transmission line is matching or not.
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TELECOMMUNICATION LABORATORY
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Impedance is the ratio of voltage to current at a point in the transmission
line, while admittance is the ratio of current to voltage at a point in the
transmission line.
Equipment Required
All experiments using FEEDBACK Microwave Trainer MWT530.
No
Component
Quantity
1
Microwave Trainer Board
1
2
Variabel Attenuator
1
3
X-band CW Gun Oscilator Source 1
4
Slotted line
1
5
Probe diode detector
1
6
Short circuit plate
1
7
Resistive termination
1
8
Waveguide horn antenna
1
9
E-plane tee
1
1. Microwave Trainer Board
Figure 7.3 Microwave Trainer Board
2. Variabel Attenuator
Is a resistive vane-central slot type; used to set attenuation level and
control power transmission in waveguides. Maximum attenuation vane
setting 0◦ approx. 36 dB; minimum at 90ᵒ less than 1 dB.
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TELECOMMUNICATION LABORATORY
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Figure 7.4 Variabel Attenuator
3. X-band CW Gun Oscilator Source
Frequency:fixed 10.687 Ghz
Output Power: 10 mW typical; 5Mw minimum.
Figure 7.5 X-band CW Gun Oscilator Source
4. Slotted line
Waveguide slotted line; for sampling electric field pattern in waveguide;
used with probe detector to measure guide wavelength, VSWR and
impedance.
Figure 7.6 Slotted Line
5. Probe diode detector
Probe detector, diode detector mounted in coaxial section with inner
conductor acting as a probe;used in conjunction with slotted line and
directional coupler to detect microwave signals. The diode detector in
waveguide mount itself is used to rectify microwave signals for their
detection; at low power levels diode detector output current is directly
proportional to the microwave power being detected.
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Figure 7.7 Probe diode detector
6. Short circuit plate
Metal plates used to short-circuit waveguide section; employed in
impedance measurements to determine reference planes, also used to
measure guide wavelength and crystal detector law in conjunction with
slotted line.
Figure 7.8 Short Circuit Plate
7. Resistive termination
Is a waveguide section containing a taper lossy material to absorb incident
microwave signals; ideally should absorb totally incoming signals without
any reflection- it then acts as a matched load.
Figure 7.9 Resistive Termination
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8. Waveguide horn antenna
Is an important microwave antenna widely used as a feed to microwave
parabolic reflectors in radio, satellite, and radar systems, and also as an
antenna in its own right.
Figure 7.10 Waveguide horn antenna
9. E-plane tee
Acts as a power divider in the plane containing the incident E (electric
field).
Figure 7.11 E-Plane Tee
Experiment Procedure
1.2.1
Measurement of VSWR using Direct Method
1. Set up the equipment as shown in figure 1.12 .
2. Set up the switch conditions on the console as follows:
Amplifier and detector: switch to detector output.
Left-hand keying switch: switch to internal keying.
Right-hand switch: initially off.
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Figure 1.12
3. Set the sensitivity to mid-position. Set the attenuator at position
20°. After switch on the console power supply, the main green
switch, then energize the microwave bench by switching the righthand switch on.
4. When the detector probe is moved along the slotted line, then the
value of current will vary. Adjust the sensitivity and, if necessary,
the attenuator setting to obtain a meter reading close to full-scale
deflection.
5. Carefully move the probe detector to locate the position of the
first minimum current. Record the 𝐼𝑚𝑖𝑛1 and the postition as x1.
6. Carefully move the probe detector to locate the position of the
first maximum current. Record the 𝐼𝑚𝑎𝑥2 and the postition as x2.
And also the next minimum current (𝐼𝑚𝑖𝑛3 ) and the postition as x3.
7. Using the same procedure, do it for short circuit and horn antenna.
1.2.2
Measurement of Impedance (normalized)
Here is how to determine the load impedance by using the Smith Chart:
1. Determine the VSWR with a direct method;
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2. Draw VSWR circle on the Smith Chart;
3. Point Q where r = 1/VSWR represents the input impedance of the
load at electric field minimum
4. Calculate the length of guide wavelength (𝜆𝑔 ) by the formula
𝜆𝑔 = 2(𝑥3𝑠𝑐 − 𝑥1𝑠𝑐 )
5. The distance d of first electric field minimum from the load input is
defined by
𝑑 = 𝑥1 = 𝑥3 − 𝑥3𝑠𝑐
6. Move 𝑑/𝜆𝑔 from the point Q .
7. Find the value of normalized load impedance.
1.2.3
Caution and equipment explanation
WARNING: Although the microwave power levels generated by the
equipment are below 10 mW and not normally dangerous, the human eye
can suffer damage by exposure to direct microwave radiation. Therefore:
NEVER look directly into an energized waveguide.
REFERENCE:
1. Manual Feedback Microwave Trainer MWT530
2. William H.Hyat and John A.Buck. Elektromagnetika, 7th ed. Erlangga.
2006
3. Stuart M. Wentworth. Fundamentals of Electromagnetics with
Engineering Aplications.Wiley.2005
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2. ANALOG MODULATION
This laboratory work is part of the Telecommunication Engineering Lab
series. Each tutorial in this series teaches you a specific topic of common
analogue modulation by explaining the theory and giving practical examples. This
tutorial covers an introduction to analogue modulation, amplitude modulation,
frequency modulation, and its properties.
2.1
Objective
In this practical, you will learn some types of analog modulation, especially
AM and FM modulation.
Theory
Modulation is the process of laying on the information signal to the signal
carrier. In other words, modulation is the process to vary the carrier signal
based on the information signal variation.
Two types of modulation schemes:

Linear modulation: linear relationship between the modulated signal and the
message signal(e.g. AM, DSB-SC, SSB, VSB).

Angle modulation: the angle of the carrier wave is varied according to the
message signal(e.g. FM,PM)
2.1.1
Amplitude modulation (AM)
Amplitude modulation uses a variation of signal amplitude to carry or
represent information. The wave that the amplitude being varied called as
carrier signal. Signal that makes the variation is called as modulating
signal (information
signal). Suppose
the carrier signal
is
vCand
the
information signal is vM, shown by equation:
vC (t) = VC sin(ωC t)
vM (t) = VM sin(ωM t)
.... (3.1)
.... (3.2)
So, the modulated signal is
v(t) = (VC + VM sin(ωM t))sin(ωC t)
.... (3.3)
It can be changed into
v(t) = VC (sin(ωC t) + m sin(ωM t)sin(ωC t))
.... (3.4)
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where m= VM /VC = index modulation. Because of
sin(ωM t)sin(ωC t)) = (1/2)[cos((ωC − ωM )t) − cos((ωC + ωM )t)],
so, there are three different frequency components, they are:

The original carrier wave, with frequency ωC , there is no variation and
doesn’t bring any information.

Components with frequency(ωC − ωM ), the amplitude is proportional to the
modulation index. This component is called as lower side frequency.

Components with frequency(ωC + ωM ), the amplitude is proportional to the
modulation index. This component is called as upper side frequency.
There are some information in lower side frequency and upper side
frequency.
2.1.2
Frequency modulation (FM)
Frequency modulation technique also involves the carrier wave and signal
information. FM
uses
frequency
changes
to
represent
the
information. Frequency variation is shown by how many changes in the phase
of result signal of modulation. At constant frequency (angular)ω radians /
second, phase changes every radians / second. Phase of carrier signal that has
not been modulated vc=Vc sinω ct is s = ωct. In FM, the signal information
varies the frequency of the carrier signal, so that the frequency of the
modulating signal becomes:
ω = ωC + DcosωM t
.... (2.5)
WhereD = kVM is peak value of deviation and k = frequency slope of
frequency modulator.
The total phase change in time, t, is
s =  ( c + D cos  mt )dt = ct  D  sin mt
 m 
…. (2.6)
so the modulated signal can be define as


v  Vc sin  c t  D  sin  mt 

m

 

vc  Vc sin ct   sin m  t  Vc F
…. (2.7)
…. (2.8)
…. (2.9)
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F  sin ct cos   sin m  t  cos ct sin   sin m  t
By using the Bessel functions,
F  J 0    sin  c t  J1    sin  c   m  t  sin  c   m  t 
 J 2    sin  c  2 m  t  sin  c  2 m  t 
 J 3    sin  c  3 m  t  sin  c  3 m  t 
…. (3.10)
...
This equation has infinite component. So it means an FM also has
sideband that is infinite number. But in practice if higher the order, Bessel
function value gets smaller, so that its bandwidth can be limited.
Equipment Required
2.1.3
No
2.1.6
1
2.1.4
2.1.7
Component
53-100
RAT
2.1.5
Measuring 2.1.8
Quantity
1
system
2.1.9
2
2.1.10 Amplitude
Modulation 2.1.11 1
Workboard 53-130
2.1.12 3
2.1.13 Computer set
2.1.15 4
2.1.16 Arbitrary
2.1.14 1
function 2.1.17 1
generator AFG 3081
2.1.18 5
2.1.19 Digital
Storage 2.1.20 1
Oscilloscope GDS-820C
2.1.21 6
2.1.22 Spectrum
Analyzer 2.1.23 1
GSP827
2.1.24 7
2.1.25 Coaxial Cable
2.1.26 2
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Figure 3.1Arbitrary function generator AFG 3081
1
2
5
3
4
6
7
1.
Carrier Frequency
5.
Time Constant
2.
Carrier Level
6.
BFO frequency
3.
Modulation Level
7.
Carrier Balance
4.
1 kHz Level
Figure 3.2 Amplitude Modulation Workboard
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Figure 3.3Spectrum Analyzer GSP827
Figure 3.4Digital Storage Oscilloscope GDS-820C
Experiment Procedure
2.1.27 Amplitude Modulation
For analog modulation, Feedback software is used. General procedure for
operating Feedback software:
a. Starting to operate Feedback software:
1. From main menu, click toolbar: system → index
2. Choose the assignment according to the practical sheet
3. Choose the practical.
b. Ending the practical:
1. Click: System → end practical
2. If you want to end your practical in Feedback software, click: System
→ quit
2.1.28 ASSIGNMENT 1 PRACTICAL 1: Amplitude Modulation with
Full
Carrier
1. Set the <carrier level> to maximum
2. Set <modulation level> to zero
3. Note the signal at all monitoring points
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4. Now increase the <modulation level> and observe at monitor point
<6>
5. Increase the <modulation level> until the carrier amplitude just reaches
zero on negative modulation peak.
6. Observe the signals at all the monitoring points both with the
oscilloscope and the spectrum analyzer at various modulation levels.
Figure 3.5 Assignment 1 Practical 1 configurations
2.1.29 ASSIGNMENT 1 PRACTICAL 2: Demodulation using an Envelope
Detector
Here the signal from the amplitude modulator from Assignment 1
Practical 1 is demodulated using an envelope detector.
1. Select <Practical 2> from the <Practicals> menu in Assignment 1.
2. Set the <carrier level> to maximum.
3. Set the <modulation level>to about half scale.
4. Set the <time constant> to minimum.
5. Use the oscilloscope to monitor the detector output at monitor point
<16> and adjust the <time constant>.
6. Increase the time constant and note that the amplitude of the detected
output.
7. Use the spectrum analyzer to observe the carrier component amplitude.
8. Compare the original modulating signal with the detector output in
both shape and phase at various time constants using the oscilloscope.
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Figure 3.6 Assignment 1 Practical 2 configurations
2.1.30 ASSIGNMENT 2 PRACTICAL 1: Double Sideband with Suppressed
Carrier
1. Use the oscilloscope and spectrum analyzer to examine the signals at
monitor point <4> and <5>.
2. Set the <carrier balance> to mid-scale.
3. Examine at <6> and note the wave shape.
4. Use the spectrum analyzer to observe that there are two sidebands but
no carrier.
5. Adjust the <carrier balance>.
6. Note the effect on carrier amplitude.
7. Adjust <modulation level> and <carrier level> and no the effect.
8. Monitor at <13> and adjust the <BFO Frequency> for stable trace, so
that the BFO is in phase with the original carrier.
9. Observe that the product detector output is the same as the modulating
signal.
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Figure 3.7 Assignment 2 Practical 1 configurations
2.1.31 Frequency Modulation
Spectrum analyzer, Function Generator, and oscilloscope are used for FM
practical
4.2.1 Time Domain Analysis
1. Switch on the function generator and oscilloscope.
2. Using coaxial cable, connect the output from the function generator
with the channel from oscilloscope.
3. Set the frequency value of the carrier signal in function generator.
4. Set the frequency deviation in function generator.
5. Push <autoset> at oscilloscope to ease the observation automatically.
6. Observe the message signal and the modulated signal at the
oscilloscope’s monitor.
2.1.32 Frequency Domain Analysis
1. Switch on the function generator and spectrum analyzer.
2. Using coaxial cable, connect the output from the function generator
with the channel from oscilloscope.
3. Set the frequency value of the carrier signal in function generator.
4. Set the frequency deviation in function generator.
5. Adjust the frequency range of view in spectrum analyzer
6. Observe the spectrum of the signal
7. Analyze by using Bessel function and Carson Rule
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3. DIGITAL MODULATION
In this chapter, we covered various aspects on digital transmission of
information at baseband frequencies. When it is required to transmit binary data
through a radio communication channel or to make more efficient utilization of
the bandwidth of a line communication channel, it becomes advantages to
modulate a carrier signal with the digital data before transmission. Three basic
forms of digital modulation, corresponding to the equivalent analog modulation
schemes of AM, FM, and PM, are known as amplitude-shift keying (ASK),
frequency-shift keying (FSK), and phase-shift keying (PSK). We will consider
each of these modulation briefly.
1.1 Objective
In this practical, you will learn kinds of digital modulation, especially ASK
modulation and FSK modulation.
Theory
Generally, information source is an analog signal, such as speech signal.
Dealing with some advantage over the analog signal, digital signal is created.
Digital communication block diagram shown below.
Figure 4.1 Digital Communication Block Diagram
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Just like basic telecommunication system block diagram, the system
consists of transmitter, channel, and receiver. As shown above, signals are
transmitted over the noisy channel. The information transmitted will be corrupted
by noise. This condition will create some information error when the signal is
received in the receiver.
The advantages of digital communication over the analog communication are:

Minimalizing the effect of noise in the signals transmitted

Easy to be multiplexed and processed

Easy to evaluate error

Cost effective implementation
a. Information Source
Information source can be a continuous signal or discrete signals. In digital
communication, analog signals should be converted into the digital one using
Analog to Digital Converter (ADC).
b. Source Encoder andDecoder
Source coding is used to code information source in order to make information
more suitable for being transmitted. Source encoder will reduce the number of
bit needed for transmitting some kinds of information. This technique will
reduce the bandwidth needed. Source decoder is used to decode information
after signals received in the receiver.
c. Line Coding andDecoding
Line coding applies digital data format without using modulation technique.
The requirements of line coding are spectrum at low frequency, transmission
bandwidth required, timing content, error monitoring, and code efficiency.
The examples of line coding are Non Return to Zero (NRZ), Return to Zero
(RZ), Manchester, Alternate Mark Inversion (AMI), HDB3, etc.
d. Encryption andScrambling
Two main reasons for using encryption and scrambling are confidentiality and
authentication.
e. Channel Coding dan Decoding
In high speed data transmission, the ‘1’ and ‘0’ are usually of very short
duration. Channel coding and decoding is applied for reducing bit errors that
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are caused by the noisy channel. Channel coding process data stream to make
it compatible with channel characteristic. The technique is applied by adding
some parity bits to the digital word.
f. Digital Carrier Modulator andDemodulator
The main purpose of digital modulator is to map binary information into
signal waveforms in order to make the binary information capable to be
transmitted over the channel.
g. Communication Channel
Communication channel is any medium that is used to transmit signals from
transmitter to receiver. In practice, the channel is noisy and will disturb
signals.
Amplitude Shift Keying (ASK)
Amplitude Shift Keying (ASK) is digital modulation technique represented by
amplitude level of the information. In ASK, binary information, such as 0 and 1,
will be stated as a different amplitude level. In a band pass ASK, the signal is
represented by:
(1)
Figure 4.2 ASK modulatedDigital signal
There are two kinds of demodulation and detection schemes for ASK: no coherent
(asynchronous) and coherent (synchronous).
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Frequency Shift Keying (FSK)
In frequecy shift keying, the frequency of the carrier varies with the baseband
informantion. For example, binary 0 will have carrier frequency f1 while binary 1
will have carrier frequency f2. The modulated signal for binary FSK is formulated
by
(2)
Figure 4.3 FSK modulatedDigital signal
FSK signals can be demodulated and detected by using both non coherent
technique and coherent technique.
Phase Shift Keying
Phase Shift Keying (PSK) is digital modulation technique that using different
phase carrier according to the binary information.
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Figure 4.4 PSK modulatedDigital signal
Equipment Required
All experiments using TEKNIKIT FEEDBACK
• 53-100 RAT Measuring system
• Modulation and Keying Workboard 53-160
Figure 4.5 Modulation and Keying Work board 53-160
4.2 Experiment Procedure
General procedure for operating Feedback software:
a. Starting to operate Feedback software:
1. From main menu, click toolbar: system → index
2. Choose your assignment according to your lesson
3. Choose practical according to your lesson
b. Ending the practical:
1. Click: System → end practical
2. If you want to end your practical in Feedback software, click: System
→ quit
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3.2.1
ASSIGNMENT23 PRACTICAL 1 :Production of ASK
1. Set all the potentiometer on work board into the middle level.
2.
See signal in every points using oscilloscope and spectrum analyzer.
Write the practical result on your practical sheet. For your information,
you can maximize your oscilloscope and spectrum analyzer view by:
2.1 Click: condition menu.
2.2 Click: change size.
3. Set MS bit switch <7> and LS bit switch <8> according to the data word
needed.
3.2.2
ASSIGNMENT 23 PRACTICAL 3 : Suppressed Carrier ASK
1. Set all the potentiometer on work board into the middle level.
2. See signal in every points using oscilloscope and spectrum analyzer. Write
the practical result on your practical sheet. For your information, you can
maximize your oscilloscope and spectrum analyzer view by:
a. Click: condition menu.
b. Click: change size.
3. Set MS bit switch <7> and LS bit switch <8> according to the data word
needed.
3.2.3
ASSIGNMENT 24 PRACTICAL 2 :Production of FSK
1. Set all the potentiometer on work board into the middle level.
2. Set MS bit switch to 0 and LS bit switch to 2
3. See signal in every points using oscilloscope and spectrum analyzer. Write
the practical result on your practical sheet. For your information, you can
maximize your oscilloscope and spectrum analyzer view by:
a. Click: condition menu.
b. Click: change size.
3.2.4
ASSIGNMENT 24 PRACTICAL 3 : PLL Demodulation of FSK
1. Set all the potentiometer on work board into the middle level.
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2. See signal in every points using osciloscope and spectrum analyzer. Write the
practical result on your practical sheet.
4.3 References
1. George W. Hutchson, John K.H. Leong, Lim Choon Kwee, Nah Cherng
Kai. “Communication Principles and Systems”. School pof Engineering,
Temasek Polytechnic, Singapore.
2. Shanmugam, Sam. “Digital Analog Communication Systems”. John Wiley
& Sons, Inc. Canada. 1979.
3. “___”.”Teknikit Digital Communication”. Feedback Instrument Ltd,
England.
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4. TELEPHONY SYSTEM
Objective

Examines how a single telephone sends and receives signals in the
telephone system.

Learning the principle of the conversion of analog signals into digital signals

Knowing the working principles of multiplexing especially TDM.
Theory
This is a simplified circuit of the whole TELEPHONE to demonstrate the
pirinciples of operation. There are 3 circuits elements used : TELEPHONE,
HANDSET and the LINE to the switching centre.
Figure 2.1 Basic Telephony system
There are three signaling circuits in the main telephone, the SWITCH
HOOK, which is operated when telephone is first lifted, the KEYPAD for sending
numbers and the ALERTER. There are also three speech circuits, a RECEIVER
(Rec), TRANSMITTER (Tx) or microphone, and the HYBRID circuit. In this
practicals, we will use three functions of telephony system : 1. Switch Hook, 2.
Keypad Operation, 3. Keypad code of DTMF for signaling detection.
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4.2.1
Switch Hook
This practical demonstrate the simple but essential function of the switch hook. Its
names derives from the first telephones in which the receiver hung from a hook at
the upright telephone. The functions are :

Signaling to the switching centre that the telephones is in use

Disconnecting the alerter, and connecting to the other telephone.
4.2.2
Keypad Operation
This practical is an introduce to the operation of KEYPAD, which uses DTMF
signaling.
4.2.3
DTMF
Dual Tone Multi-Frequency signaling, or Touch tone dialing. There are 7
frequencies available in the keypad circuit. The two frequencies are chosen from a
set of 4 low frequencies (697 to 941 Hz) and 3 high frequencies (1.21 to 1.48
KHz). One low and one high frequency are used for each button.
Figure 2.2 DTMF signaling on keypad
DTMF signaling is a replacement for the pulse dialing previously used in
automatic telephones. Pulse dialing operates at the 10 pulses per second, by
interrupting the current flow from the SLIC.
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4.2.4
PCM
Transmitted signals will decrease the quality. This degradation is caused by
theexistence of things, among others:

Attenuation

Noise

Interference
To reduce these impact, the analog signals need to be converted to digital
form, because it is more resistant to noise and attenuation. The conversion of
analog signals into digital form through three stages of the process of sampling,
quantization, and coding that all three are part of the Pulse Code Modulation
(PCM).
Sampling
Sampling is the process of measuring the amplitude of a continuous-time
signal at discrete instants. It converts a continuous-time signal to a discrete-time
signal.Sampling frequency which is usually used in the process of digitizing the
voice signal is 8 KHz for digital telephony. Mathematically this can be
analogous to sampling as a result of multiplication (combining) signals are
sampled with a sampling signal. Here is a picture of the information signal, the
signal wave sample and sampling results:
Figure 5.1 Information Signal
Figure 5.2 Digital Signal
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Figure 5.3 Signal Sampling Result
Quantization
Quantization represents the sampled values of the amplitude by a finite set of levels.
It converts a continuous-amplitude sample to a discrete-amplitude sample. In this
quantizing many comparator level is 2n where n is the number of bits used.
Coding
Coding designates each quantized level by a (binary) code. Here is a picture of
quantization and coding process:
Figure 5.4 Quantizing
Figure 5.5 Coding
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4.2.5
TDM
Multiplexing is a method of using a channel of communication together.
Multiplexing is intended to save resources from the communications channel. One
form of multiplexing is the Time Division Multiplexing (TDM).TDM is the time
interleaving of samples from several sources so that the information from these sources
can be transmitted serially over a single communication channel.In which one frame is
divided into several time slots. Each time slot has the same period and each frame has
the same number of time slots, so each time slot on each channel talks repeatedly at
fixed intervals, so that TDM is a synchronous system. Time slots can be used by one
user to a channel talks. Other types of multiplexing are Frequency Division
Multiplexing (FDM) and Code Division Multiplexing (CDM).
Figure 5.6 The principle of time divison multiplexing (TDM)
Equipment Required
All experiments using TEKNIKIT FEEDBACK
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4.2.6
No
4.2.9
1
4.2.7
4.2.10 53-100
Component
RAT
4.2.8
Quantity
Measuring 4.2.11 1
system
4.2.12 2
4.2.13 Telephone and Interface 4.2.14 1
58-100
4.2.15 3
4.2.16 Computer set
4.2.17 1
Figure 2.3Telephone and Interface 58-100
Experiment Procedure
USING FEEDBACK SOFTWARE Practical Instruction (done at the time of
beginning using software Feedback)

From the main menu to find out the tasks to be performed, click toolbar >>
index. It will show a collection of assignment.

Click the assignment you are doing

Then click the toolbar Practical accordance with the practical you are
doing
To proceed to the next practical,
a. click toolbarSystem>>End practical
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b. Then start over by clicking the next toolbarPractical.
ASSIGNMENT 1 PRACTICAL 1 : SWITCH HOOK
1. Press the button below the microphone handset,
2. Note the operation change-over switch and reading on the ammeter
ASSIGNMENT 1 PRACTICAL 2 : KEYPAD OPERATION
1. Switch the telephone to the ‘TONE’ position
2. Keep the telephone Off Hook, and leave the line current control at the normal
centre position
3. Press one button on the keypad. Observe the signal on the line, shown on the
oscilloscope. Keep the button pressed for this. Use the ‘options’ menu to
display the full screen oscilloscope
ASSIGNMENT 4 PRACTICAL 1 : KEYPAD CODES
1
Press the button on keypad
2
Observe the signals on the line
3
Observe the frequency of signal at the output of each filter
ASSIGNMENT 7 PRACTICAL 1 and 4: Basic Sampling and Aliasing Error
1. Follow the general instructions. click toolbar practical → basic sampling
2. Set frequency of oscilloscope 1 to approximately 800 Hz and output Vpp 2 volt.
(Change display size with a `menu option ').
3. Observe the waveform on the oscilloscope 1, the clock, the sampling wave (at
test point 7) and the output on the low pass filter. Analysis it!
4. Change the sample time by using the menu 'option' to ¼. Observe the
waveform occurs. Analysis it!
5. Repeat step 3 by changing the sample time into 1 / 8.
6. Repeat steps 1-3 for 500 and 2 kHz frequency.
7. Analysis the result
ASSIGNMENT 9 PRACTICAL 1 : Quantizing
1. Follow the general instructions. click toolbar practical → quantization
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2. Set the voltage to 0 (zero) volt, using `DC Test Linear controllers' and
recalibration to get accurate results.
3. Set the input voltage to 1 V, observe the digital output.
4. Repeat for 2 V and a maximum voltage untill the digital display does not
change. Observe the digital output.
5. Repeat to -1 V and -2 V and to a minimum. Observe the code changes' at zero
voltage.
6. Analysis!
ASSIGNMENT 9 PRACTICAL2 : Quantizing Noise
2. Follow the general instructions. click toolbar practical → quantization noise
3. Set the frequency at 300 Hz and voltage amplitude (peak) at 0.2 volts by
using the controller `Fine control '.
4. Set the resolution to 4 bits, by using the menu 'Option ".
5. Observe the digital output (test point 7) and the results of the output filter (test
point 8)
6. Repeat for different bits of resolution.
7. Use the 'spectrum analyzer' to see the output
8. Analysis!
ASSIGNMENT 9 PRACTICAL1 : Introduction of Multiplexing
1. Follow the general instructions. click toolbar practical→introduction to
multiplexing
2. Observe the output on the oscillator 4 which is a result of demultiplexing (test
point 7) and output filters.
3. Compare the form of waves (test point 14) by using a large display. set
oscillator 1 to 0 (zero) volt and varying the amplitude to determine the time
slots used by each signal.
4. Increase the output value of oscillator 1.
5. Compare the input waveforms for each oscillator with output wave by using
the menu `option 'to choose a time slot.
5. FIR filter using DSK TMS320C6713
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Objectives

Understand the DSP and its applications

Understand the concept of FIR filters and design FIR filter
Theory
5.2.1
Overview of DSK
DSK TMS320C6713 is one of the types C6000 that can work on a fixed-
point or floating-point. However, DSP is still a starter kit, which is a platform that
can simulate DSP C6713. This type is intended for educational purposes, research,
and evaluation. However, the results of the application that we created in the DSK
type is very likely to apply to the actual C6713 DSP.
Texas Instruments publish a series of DSP board for applications DSP
processors with low cost, one of which is a series of DSK TMS320C6713 DSP
board. Basically, this board was developed as a low-cost platform that has high
performance to facilitate learning for all about digital signal processing. On the
DSP board is already integrated components that related with signal processing
using DSP (Digital Signal Processor). Components of board is hardware, but can
be programmed using Code Composer Studio software. In Figure 1 and Figure 2
respectively display DSK TMS320C6713 and the block diagram of DSK
TMS320C6713.
Figure 1.1 Display DSK TMS320C6713
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Figure 1.2 Block diagram of DSK TMS320C6713
The main components as well as supporters of the DSK TMS320C6713 include:

Processor TMS320C6713
It is a processor with a clock speed of 225 Hz which support the operation
of fixed-point and floating-point. Operating speed can reach 1350 million
floating-point operations per second (Mflops) and 1800 million
instructions per second (MIPS). In addition, the processor is able to
perform 450 million multiply-accumulate operations per second.

CPLD (Complex Programmable Logic Device)
CPLD contains registers that serves to regulate the features that exist on
the board. On the DSK C6713, there are 4 types of CPLD registers,
namely:
2. USER_REG, Register to set switches and LEDs as desired by users.
3. DC_REG, Register to monitor and control the daughter card.
4. VERSION Register for indications that related to the version of the
board and CPLD.
5. MISC Register to manage other functions on the board.

Flash memory
DSK uses flash memory to booting. In the flash contains a small program
that called POST (Power On Self Test). This program is run when DSK
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was first on. POST program will examine the basic board functions as a
USB connection, audio codec, LEDs, switches, and so on.

SDRAM
The main memory that serves as a repository of instructions and data.

AIC23 Codec
Serves as ADC and DAC for the incoming signal to the board.

Daughter card interface
Additional connectors are useful for developing applications on board.
There are three connectors, namely memory expansion, peripheral
expansion, and Host Port Interface.

LEDs and Switches
LEDs and switches is a feature that can help in building applications
because can be programmed as desired by the user.

JTAG (Joint Test Action Group)
Is a connector that can transfer data at very high speeds. This will be
useful in real-time applications.
DSK can be used for many things, ranging from communication
simulation, control system to image and sound processing. DSP commonly used
in communications applications (mobile). Embedded DSP can be found in cellular
phones, fax / modems, disk drives, radios, printers, hearing aids (hearing aids),
MP3 player, high-definition television (HDTV), digital cameras and others. The
use of DSP in many tools can reduce the price of production, because the DSP can
be programmed according to the needs, the softaware is cheap and sufficient
hardware support.
5.2.2
Digital Filters
The digital filter is a mathematical procedure or algorithm that processes
the digital input signal and generates a digital output signal that has certain
properties in accordance with the purpose of the filter. This filter can use in many
applications. Most of the signal processing applications using filters. In PSD, the
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filter that designed is digital filter. Digital filter can be divided into two IIR
Digital Filters (infinite impulse response) and FIR (finite impulse response). This
division is based on impulse response filter. FIR has a finite impulse response
length, whereas IIR infinite. FIR not has pole, then the stability can be guaranteed,
while IIR has poles so more unstable. In the high-order digital filter, error that
happen because rounding the filter coefficients can cause instability.
In general:
a. Finite Impulse Response (FIR)
Formula FIR can be seen as follows:
N 1
y (n)   h(k )x(n  k )
(1)
k 0
b. Infinite Impulse Response (IIR)
IIR formula can be seen as follows:

y ( n)   h( k ) x ( n  k )
(2)
k 0
The basic operation that used in signal processing just a simple
multiplication and summation. However, these two operations are performed is
very numerous, so to implement in the application is required a very fast
processor to perform mathematical calculations. So, designed a microprocessor
that works specifically for digital signal processing called the Digital Signal
Processor (DSP).
5.2.3
FIR Filter
FIR filter serves to operate a real-time digital filter on a DSP. Named
"finite" or limited because there is no feedback on the type of filter. There is no
feedback because the value of a signal sample is limited to the value of (N-1) so
that the number of samples depends on the number of coefficients N. On the
TMS320C6713 DSK, the use of FIR filters include the use of the ADC and DAC
are integrated with the DSP board. ADC serves to capture and transform the
signal into discrete form, whereas the DAC function transform back into an
analog signal.
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In general, an FIR is defined by the impulse responses, h(n), where h(n) is
filter coefficients as found in Figure 3. The value and number of filter coefficients
are determined by the desired filter specifications. Manually a value and the
number of filter coefficients can be searched using a variety of methods that
exploit the concept of discrete Fourier transform and windowing techniques.
Figure 1.3 FIR Filter
with bi is the value of filter coefficients and q is number of filter coefficients.
Equipment Required
In practical to this module used such tools in Table 1 below.
Table 1 Equipment used in Module Digital Modulation
No
Component
Quantity
1
DSK TMS320C6713
1
2
Software MATLAB
1
4
Software Code Composer Studio
1
5
Microphone
1
6
Audio Speaker
1
Experimental Procedure
In general, this experiment using MATLAB Simulink software and
integrated with CCS studio so it can be programmed on the TMS320C6713 DSK.
The above process is called as the targeting process. For digital filter design is
done in Simulink with the help of FDA Tool.
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5.2.4
targetting Simulink in the DSK TMS320C6713
Simply, the targeting process used SIMULINK ® and CCS. To connect
SIMULINK with DSK needed ® Real Time Workshop, Embedded Target for TI
C6000 DSP, and Link for CCS. These three things can be found in SIMULINK ®
and must be done configuration settings. The third relationship that can be seen in
the figure below.
In Figure 2 below show the process of debugging and verification
conducted by the CCS software. The use of CCS allows to generate codes that
will be used in the DSP C6000 so that no need programming manually because it
was done by the CCS
Figure 1.4 Flowchart of targetting in DSK C6000
5.2.5
Design of Filters
Designing Filters use the help of Filter Design and Analysis (FDA) tool
that found in MATLAB software. The results from the use of this tool will be
obtained FIR filter coefficients required specifications. In this design, used
methods Blackman.
Specification of Digital Filter design:

Low Pass Filter

Sampling Frequency (fs) = 16 000 Hz

Cut off Frequency (fs) = 3000 Hz

Transition Width = 1000
In this design method is used Blackman
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f = transition width / sampling frequency
= 1000 Hz/16000Hz
= 0.0625
The number of coefficients
(N)
= 3.3 / f
= 3.3 / 0.0625
= 53
Furthermore, the number of coefficients will be entered into the FDA tool.
5.2.6
Practical Procedures
By using the filter specifications such as the example above, then the steps
to create a filter is as follows: (Assistant MUST accompany)
1. Open the Simulink file FIR.mdl. Then, DSK connect with a computer, Perform
diagnostics and enable the studio CCS program when there is no alarm;
2. Then open the block FDA Tool in FIR.mdl (available 3 blocks FDA tool where
each FDA tool will be controlled by a single button on the DSK). In Figure 3
below display the simulation FIR filter
Figure 1.5 Display FIR filter simulation
3. Fill in the desired filter specifications on the display are simulated as in Figure
4 below;
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Figure 1.6 Input simulation parameters
4. Perform targetting from Simulink to DSK TMS320C6713 by pressing the
incremental build as contained in Figure 5 below. Remember DO NOT SAVE
IN;
Figure 1.7 Display icon to perform targetting
5. Connect the Line in DSK with output on the computer, and Line Out DSK on
the computer microphone input. Connect the headphones on DSK with
Loudspeaker;
6. Open the file 44100.wav that will serve as an input audio signal. This file is
generated signal at a frequency of 100-7000 Hz;
7. Open the file spectrumliat.mdl and run it;
8. Press the DIP switch on the DSK to see the results of the filters;
9. Fill borang observations and perform the above steps to design a filter with the
specifications given by the assistant then. In the process of targeting the
experimentalist must be accompanied by an assistant.
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6. RADIO LINES USING RADIO MOBILE SOFTWARE AND
MINI-LINKTM DEVICES
6.1
Objective
1. Learning to simulate one or more radio lines with modified
parameters using Radio Mobile software
2. Understanding type and function of components on MINI-LINK
Theory
6.2.1
General Theory
Radio waves which propagating on the air will experience several
different physical phenomena, such as reflection, transmission, diffraction and
scattering. Propagation environment is the geographical environment in which
radio waves propagate from transmitter to receiver. Propagation environments
strongly influenced by the physical parameters such as pressure, temperature,
humidity, refractive index, topography, vegetation distribution, roads, and
buildings. Radio wave propagation can be determined by modeling the
different physical mechanisms, such as damping vacuum, atmospheric
attenuation, attenuation due to vegetation, and others.
The simplest radio propagation is line-of-sight. Microwave signals can
be blocked by buildings or valleys. The waves must avoid any obstacles or tilt
on the earth to make transmission. If the position between the building is
blocked, it is necessary to put an antenna tower higher, in order to remain in a
position to "see each other" (line of sight). In general, the propagation is called
line-of-sight if there are no waves diffraction effects, this means that there is
no obstacles in first Fresnel ellipsoid. In Figure 7.1 below shown a simple
model of radio propagation path analysis line-of-sight.
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TELECOMMUNICATION LABORATORY
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Figure 9.1 Simple Radio Line Propagation
In Figure 9.1, the power vacuum propagation loss(free space loss)
is given by equation (1) below.
(1)
If transmission loss, LR and LT on Figure 1 is not counted, the power
received is
(2)
All units on quotation (2) on International Standard.
6.2.2
Radio Mobile Software
The first step to create a wireless system is to make a design and
simulation of the system. One of the tools to design and simulate a wireless
system is the software Radio Mobile. Radio Mobile is a software developed
byRoger Coude for amateur radio users. Radio Mobile using digital
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TELECOMMUNICATION LABORATORY
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terrainelevation model for the calculation of the coverage and signal
strengthreceived at various points along the radio path. Radio Mobile
automaticallybuilds a profile between two points on a digital map showing
the coverage area and first Fresnel zone. During the simulation, the software will
check the line-of-sight and calculate the path loss. By using Radio Mobile, it is
possible to make a network of several different topologies, including network
master/slave, point-to-multipoint. This software can be used to calculate the
coverage area of a base station in a point-to-multipoint, working for a system that
has frequency of 100 kHz to 200 GHz.
6.2.3
TM
MINI-LINK
Ericsson is a company that already has experience in the field of
microwave technology for over forty years and experience in the field of
telecommunications for more than 130 years. Ericsson was the first company
that has successfully demonstrated the direct speed of 2.5 Gbps over the air
and also the first to introduce commercial products with a 512 QAM
modulation.
MINI-LINKT M manufactured by Ericsson in its own factory in
Sweden. Ericsson has had extensive experience of MINI-LINKT M ranging
from planning to construction of MINI-LINKT M networks around the
world. MINI-LINKT M a microwave transmission technology devices are
the most widely used around the world.
MINI-LINKT Mis the world's leading microwave solution, suitable
forany network scenario. It enables flexible and speedy network rollout, and
provides gigabit capacity and carrier-grade availability. Ericsson's
microwave offering consists of a number of products:
MINI-LINKT MTN, a modular solution for evolving networks
providingtransport technology flexibility and integrated traffic handling
MINI-LINKT MCN, compact and cost efficient hop solutions
formicrowave transport
MINI-LINKT MPT, all outdoor solutions for packet microwave transport
MINI-LINKT MSP, multi access aggregation node and indoor unit for
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MINI-LINKT MPT
MINI-LINKT MLH, an Ethernet Trunk Radio providing high capacities
over long hops
Marconi LH, a compact high-capacity trunk radio solution for SDH
Figure 9.2 Ericsson Microwave Portofolio
Ericsson developed a microwave as the transmission technology for
several reasons:
• Environmental conditions that are difficult to reach. Especially
inIndonesia, many environmental conditions such as islands, mountains,
forests, etc.. Environmental conditions like this right if you use radiobased transmission techniques (microwave).
• The implementation does not take a long time. To build an optical fiberbased transmission lines, sometimes it takes more than six months.
• The high cost of installation per meter of fiber optic technology.
• Transmission technology is easy to add capacity and capabilities.
Some applications that take advantage of MINI-LINKTM is a mobile
network, the transmission of an enterprise to operator, transmission networks in
government and the military, and microwave backbone network. In figure 7.3
shown some application MINI-LINKTM .
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Figure9. 3 MINI-LINKTMapplication
MINI-LINK equipment on Telecommunication Laboratory:
1. Outdoor units (ODU) consisted of a radio unit (RAU) and a
compact antenna. ODU is the part that relates to the frequency bands
allocation and in no way depends on the traffic.
a) Radio unit (RAU)
The basic functions of the radio unit (RAU) is to transmit and
receive RF signals and converts them to / from the cable signal
format radio (cable radio). Cable radio is part of that serves to
connect the RAU and MMU (Modem Unit). RAU can be
connected to an antenna that has a wide band width on an
integrated system or separately. RAU connected to the antenna
through a waveguide interface. RAU removal and replacement
can be done without affecting the antenna.
Figure 9.4 Radio unit MINI-LINKTM
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Radio frequency spectrum available on the MINI-LINKTM RAU
is 6, 7, 8, 10, 11.13,, 15, 18, 23, 26, 28, 32, 38 GHz for Radio Split
and 70/80 GHz for All Indoor. Here is a performance RAU table.
Tabel 9.1 RAU MINI-LINKT M Performance
b. Antenna
Microwave antennas on the MINI-LINK have a diameter variation
between 0.2 m to 3.7 m, and consists of a singlepolarization and
dual polarization. All antennas are compact, or in other words
low profile. Shown in Figure 7.5 MINI-LINK microwave
antennas.
Figure 9.5 Antenna
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Antenna with RAU can be a separate system or integrated, as there are
in Figure 7.6 (a) and 7.6 (b). In Table 7.2 show specifications antenna
used on MINI-LINKT M.
Figure 9.6 Antenna which separately installed with RAU and antenna
which installed integrated with RAU on MINI-LINKT M
Tabel 9.2 Antenna specification used on MINI-LINKT M
2. Indoor Unit (IDU)
Indoor section, the access module, a part that was in the room. IDU traffic
capacity version is supplied with different modulation schemes (CQPSK or 16
QAM), system configuration, and does not depend on the frequency band used.
Modules contained in the Mini-Link E are not all the same as the modules
contained in the Mini-Link TN.
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The following are IDUs devices, both of which are on the Mini-Link E as well
as the Mini-Link TN, which was granted by PT Ericsson Indonesia to DTE FTUI:
a. Access Module Magazine (AMM)
AMM is a place to put a variety of indoor devices. AMM is comprised of
various sizes. In the Mini-Link E, AMM measures include: AMM 2U-3,
and AMM 4U1, while the Mini-Link TN, ukran AMM AMM including 1p,
2p B AMM, AMM 6p C, AMM 6p D, and AMM 20p B . Keep in mind, U
is a unit of length dimension which is used to indicate the height AMM, U =
44 mm. AMM can be mounted fitting into 19-inch racks.
AMM installed on MINI-LINKT M in Telecommunication Laboratory DTE
FTUI is:
AMM 2U-3 for Mini-Link E
AMM 2U-3 can be mounted 1 piece SAU2: one high school, and two
MMU. The modules are mounted on AMM 2U-3 in the
Telecommunications Laboratory DTE UI is one fruit and one fruit SMU
MMU. Display shown in Figure 7.7 AMM 2U-3.
Figure 9.7 AMM 2U-3
Keep in mind, the composition of the modules tepasang the AMM shall
comply with the provisions as shown in Figure 7.8. If only one MMU is
installed, then the MMU must be placed in the second slot (second from
top).
Figure 9.8 Slot on AMM 2U-3
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AMM 2p B for Mini-Link TN
AMM 2p B consists of four slots, the slots 00, 01, 02, and 03. 00 slots
reserved for NPU3 or NPU3B. The power supply required for the AMM 2p
B is a DC voltage of -48 V or +24 V. Display shown in Figure 9 AMM 2p
B and arrangement of the AMM 2p slot B.
Figure 9.9 AMM 2p B (a) and
Slot on AMM 2p B (b)
b. Modem Unit (MMU)
MMU is a modulator and demodulator unit. MMU can be mounted on a
Mini-Link E-and Mini-Link TN. MMU Mini-Link E produced Ericsson
consists of various size capacities, including 2x2 Mbit / s, 4x2 / 8 Mbit / s,
2x8 Mbit / s, 2x8 Mbit / s, 34 +2 Mbit / s, and the MMU can directly have
the capacity 2x2Mbit / s - 34 +2 Mbit / sMMU on Telecommunications
Laboratory DTE UI is MMU 2x8 Mbit / s are used for Mini-Link E.
Display shown in Figure 10 MMU 2x8 Mbit / s.
Figure 9.10 MMU 2x8 Mbit/s
In Table 7.3 below the MMU specification described in the
Telecommunications Laboratory DTE UI. In the block diagram shown
Figure 7.11 MMU 2x8 Mbit /s.
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TELECOMMUNICATION LABORATORY
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Table 9.3 MMU 2x8 Mbit/s Specification
Figure 9.11 MMU 2x8 Mbit/s block diagram
c. Switch Multiplexer Unit (SMU)
SMU is a unit that works to reduce traffic from MMU and / or provide
protection for the benefit of switching between microwave network
connection. SMU consists of several types, such as Sw (2 & 4 E1), 8x2
Mbit / s, and 16x2 Mbit / s. SMU found on the Mini-Link E. SMU in the
Telecommunications Laboratory DTE UI is SMU 8x2 Mbit / s. In Figure
7.12 and 7.13 respectively shown SMU 8x2 Mbit / s and the block diagram.
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Figure 9.12 SMU 8x2 Mbit/s
Figure 9.13 SMU 8x2 Mbit/sblock diagram
d. Node Processor Unit (NPU)
NPU is the brain of the Node. NPU holds the overall configuration of
Node. DCM LAN connection are the NPU. In addition, there is also a USB
port if you want to use the Local Craft Tool (LCT). NPU consists of several
types, including NPU1 B, NPU1C, NPU3, and NPU3 B.
Figure 9.14 NPU 3
In addition to the ODU and IDU above, there are also other components
contained in the MINI-LINKT M's in Telecommunications Laboratories
DTE UI.
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1.
Radio Cable
Radio cable is a cable used as a waveguide. In other words
diberfungsi radio wiring for guiding radio waves.
2.
Coaxial Connector
Coaxial cable connector also called radio connector. Coaxial
connector is used for connecting between the coaxial cable as well as
coaxial xable with a device having input/output ports of radio waves. In
figure 7.16 shown the various types of coaxial connector used on the MINILINKTM contained in the Telecommunication Laboratory DTE UI.
Figure 9.15 Types coaxial cable used on MINI-LINKTM
3.
Grounding Cable & Grounding Bar
Grounding cable and grounding grounding bar is a device that aims to
protect if there is excessive current.
Figure 9.16 grounding bar
4.
Mini Circuit Breaker (MCB)
MCB serves as a contact point and the power supply breaker.
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Figure 7.17 MCB
5.
LSA
LSA used as a place to put traffic connection cable.
Figure 7.18 LSA
6.
19 inchi rack
19 inch rack used as a place to put modules, power supplies, DC
power distribution, DDF panels, etc.
Figure 7.19 19 inch rack
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7.
E1 Cable
E1 Cable is where traffic is channeled.
Figure 7.20 E1cable
8. Dummy Unit
Dummy units are used if there is an empty slot in the AMM. Dummy units
required as the device is essential to maintain the cooling air in the AMM.
Figure 7.21 Dummy unit
9. Cooling Arrangement (Fan Unit)
FAN works to provide cooling unit is good and right for the Node.
Figure 7.22 Fan unit
10. Software
This software is used to configure and analyze MINI-LINKT M performance.
Mini-Link Service Manager
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Mini-Link Craft
3.
Equipment Required
Table 4 The equipment that used in the Module Path Using Software
Radio Mobile Radio and Microwave Radio Path using the MINILINK Produced by Ericsson
No
1
2
4
5
6
7
Component
Quantity
Radio Mobile Software
1
MINI-LINK E Device
1
MINI-LINK TN Device
1
MINI-LINK Service Manager Software 1
Insertion tool
1
Computer
1
Practical Procedures
6.2.4
Radio Line using Radio Mobile Software
Point-to-Point Radio System
1. Open Radio Mobile software (rmweng.exe);
2. Open the Folder Properties (F8), select the name of the city with
Select a city name or enter a position (lattitude and longitude) of the
city and select the size of the image (Size height);
3. Open the Network properties (ctrl N), then open System. Make
the desired system. Set the parameters of the system;
4. Open unit properties (ctrl U), place the appropriate unit
desired location;
5. Open the Network properties, and open membership, specify
the system used for each unit;
6. To display all units on the map, click View, then click Show
network, and the click All.
7. Calculate the link budget for the link by clicking Tools, then
click the radio link (F2). It can also display the details of the
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simulation output. (Tools → Radio → link → view details)
8. Change parameters, such as antenna height, the unit being TX .
RX. Give your analysis!
Repeater on Point-to-Multi Point Radio System
1. Open Radio Mobile software (rmweng.exe);
2. Open the Folder Properties (F8), select the name of the city with
Select a city name or enter a position (lattitude and longitude) of the
city and select the size of the image (Size height);
3. Open the Network properties (ctrl N), and open the Parameters.
Make the desired parameters. Set the parameters of the parameter;
4. Select System. Create two systems (repeaters and hand held) is
desired. Set the parameters of the parameter;
5. Select Membership.
For repeater:
• Select Command on Role of Repeater table;
• Repeater on System.
For Hand held:
• Select Subordinate on Role of Repeater table;
• Hand held on System.
6. Click Tools, select Coverage, select Find best site
7. Give your analysis!
References:

H. P. Westman et al., (ed), Reference Data for Radio Engineers, Fifth
Edition, 1968, Howard W. Sams and Co., no ISBN, Library of Congress
Card No. 43-14665 page 26-1

Demetrius T Paris and F. Kenneth Hurd, Basic Electromagnetic Theory,
McGraw Hill, New York 1969 ISBN -0 048470-8, Chapter 8

Christopher Haslett, Essentials of radio wave propagation, Cambridge
University Press, 2008 052187565X pages 119-120

MINI-LINK Overview for University 2010-06-21 PA1, Ericsson.
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
MINI-LINK E ETSI Technical Description Rev B, Ericsson, 2005

Mariantoro, Rony. Mini-Link E & TN Operation and Maintenance. PT.
Ericsson Indonesia, 2010.

Petunjuk Konfigurasi Mini-Link E dan Traffic Node, Ericsson, 2010
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