Forth Edition
Louis Frenzel
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Wireless Technologies
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.








21-1: Wireless LAN
21-2: PANs and Bluetooth
21-3: ZigBee and Mesh Wireless Networks
21-4: WiMAX and Metropolitan-Area
Networks
21-5: Infrared Wireless
21-6: Radio-Frequency Identification and
Near-Field Communications
21-7: Ultra Wideband Wireless
21-8 Additional Wireless Applications
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.



In addition to cell phones, there are many
more wireless systems and applications in
common use today.
These are primarily short-range systems that
have a range of a few inches up to several
miles depending upon the application.
Each of these popular systems is defined by a
specific industry standard and is identified
with one or a few well-known applications.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Figure 21-2: Types of WLANs. (a) Access point extension to a wired LAN. (b) Public
access point via an Internet service provider (ISP).
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.




Local-area networks (LANs) within a company or
an organization are still interconnected mainly
by CAT5 or CAT6 twisted pair.
Wireless extensions and even complete wireless
LANs have become more common now that
reliable, low-cost wireless modems are available.
Wireless is a great way to expand an existing
network.
What makes the wireless LAN so appealing is
that it offers flexibility, convenience, and lower
costs.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.



Wireless access points (APs) are available not
only within offices, but also in restaurants,
coffee shops, airports, hotels, convention
centers, and other public places.
Access points are more commonly known as
“hot spots.” Some cities are installing municipal
hot spots.
Anyone with a laptop equipped with a LAN
modem interface can link up to the AP and
access his or her e-mail or the Internet. There are
hundreds of thousands of hot spots around the
world.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.



Another growing use of wireless LANs is in the
implementation of home networks.
Installing a wireless LAN is fast, easy, and very
inexpensive. A special box called a residential
gateway or wireless router connects to the
cable TV or DSL and serves as the access point.
This gateway or router uses a software approach
called network address translation (NAT) to
make it appear as if each networked PC has its
own Internet address, when in reality only the
one associated with the incoming broadband
line is used.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Hardware of Wireless LANs
 The hardware devices in a wireless LAN are the access
point or the gateway/router and the radio modems in
the PCs.
 The access point is a box containing a transceiver that
interfaces to an existing LAN by way of CAT5/6 wiring.
 It gets its dc operating power via the twisted-pair
cabling.
 The IEEE 802.3af standard related to furnishing dc
power over the network cable is referred to as Power
over Ethernet (PoE).
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Hardware of Wireless LANs
 In a home network, the gateway or router is
designed to attach to the DSL or cable TV modem
with CAT5/6 cable.
 It often attaches to one of the PCs in the home
network by cable.
 The other PCs link to the gateway/router
wirelessly.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Wireless LAN Standards
 One standard for wireless LANs has emerged as the




most flexible, affordable, and reliable.
Known as the IEEE 802.11 standard, it is available in
multiple forms for different needs.
The earliest useful and most widely adopted version
of the 802.11 standard is 802.11b.
It operates in 11 channels in the 2.4-GHz unlicensed
ISM band.
This band extends from 2.4 to 2.4835 MHz for a total
bandwidth of 83.5 MHz.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Wireless LAN Standards
 The access method is direct sequence spread
spectrum (DSSS) so that multiple signals may share
the same band.
 The 802.11b standard specifies a maximum data rate
to 11 Mbps. This rate is achieved only under the most
favorable path conditions.
 Increasing range or noise causes the rate to
automatically drop off to 5.5, 2, or 1 Mbps, which
helps ensure a reliable connection despite the lower
speed.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Wireless LAN Standards: IEEE 802.11n
 The newest standard is the 802.11n version.
 It uses the 2.4-GHz band and OFDM.
 A primary feature of this standard is the use of
multiple-input multiple-output (MIMO) antenna
systems to improve reliability of the link.
 APs for 802.11n use two or more transmit antennas
and three or more receive antennas. The wireless
nodes use a similar arrangement. In each case
multiple transceivers are required for the AP and the
node.
 MIMO systems reduce multipath problems and
extend the range and reliability of the wireless link.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Wireless LAN Standards: Wireless Security
 The 802.11 standard also includes provision for
encryption to protect the privacy of wireless users.
 Since radio signals can literally be picked up by
anyone with an appropriate receiver, those concerned
about privacy and security should use the encryption
feature built into the system.
 The basic security protocol is called Wired Equivalent
Privacy (WEP) and uses the RC4 encryption standard
and authentication.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Wireless LAN Standards: Wireless Security
 WEP may be turned off or on by the user. It does
provide a basic level of security; however, WEP has
been cracked by hackers and is not totally secure from
the most high-tech data thieves.
 Two stronger encryption standards called Wi-Fi
Protected Access (WPA) and WPA2 are also available
in several forms to further boost the encryption
process.
 The IEEE also has a security standard called 802.11i
that provides the ultimate in protection.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.




A personal-area network (PAN) is a very
small network that is created informally or on
an ad hoc basis.
A PAN typically involves two or three nodes,
but some systems permit many nodes to be
connected in a small area.
PANs can be wired, but today all are wireless.
The most popular wireless PAN system is
Bluetooth, a standard developed by the cell
phone company Ericsson for use as a cable
replacement.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.



Bluetooth is a digital radio standard that uses
frequency-hopping spread spectrum (FHSS)
in the unlicensed 2.4-GHz ISM band.
Three levels of transmission power have been
defined, depending upon the application.
Bluetooth transceivers are available as singlechip transceivers that interface to the device
to be part of a PAN.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.




Bluetooth transceivers send out search signals
and then listen for nearby Bluetooth-equipped
devices.
If another Bluetooth device comes into range,
the two Bluetooth devices automatically
interconnect and exchange data.
These devices form what is called a piconet, the
linking of one Bluetooth device that serves as a
master controller to up to seven other Bluetooth
slave devices.
Bluetooth devices can also link to other piconets
to establish larger scatternets.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Figure 21-3: Bluetooth piconet with scatternet link. Up to seven devices can be actively
connected.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.



The main applications for Bluetooth are cordless
headsets for cell phones, wireless connections
between PCs, or laptop computers and PDAs.
Bluetooth applications include: laptop
connections at meetings, wireless printer-to-PC
connections, laptop-to-cell phone connections,
wireless audio headsets, and wireless digital
camera-to-TV set connections.
The Bluetooth standard is maintained by the
Bluetooth Special Interest Group (SIG) and
supported by more than 2000 manufacturers.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.




ZigBee is the commercial name for another
PAN network technology based on the IEEE
802.15.4 wireless standard.
Like Bluetooth, it is a short-range technology
with networking capability.
It was designed primarily for commercial,
industrial, and home monitoring and control
applications.
ZigBee is designed to operate in the licensefree spectrum.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.


There are three basic bands and versions (below).
Data rates are low, but most applications are
simply transmitting sensor data or making simple
on/off operations.
Frequency
Band
Number of
Channels
Modulation
Max. Data Rate, Kbps
868 MHz
(Europe)
1
DSSS/BPSK
20
915 MHz
1
DSSS/BPSK
40
2.4 GHz
16
DSSS/O-QPSK
250
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.



ZigBee’s virtue is its versatile networking
capability.
The standard supports three topologies: star,
mesh, and cluster tree. The most commonly
used are the star and mesh.
These network topologies are made up of
three types of ZigBee nodes:
 ZigBee coordinator (ZC)
 ZigBee router (ZR)
 ZigBee end device (ZED).
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.




The ZC initiates a network formation. There is
only one ZC per network.
The ZR serves as monitor or control device
that observes a sensor or initiates off/on
operations on some end device.
It also serves as a router as it can receive data
from other nodes and retransmit it to other
nodes.
The ZED is simply an end monitor or control
device that only receives data or transmits it.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Figure 21-4: Most common
ZigBee network topologies.
(a) Star. (b) Mesh.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.


In the mesh topology, most of the nodes are
ZRs that can serve as monitor and control
points and can also repeat or route data to
and from other nodes.
The mesh topology can greatly extend the
range of the network, and enhance its
network reliability or robustness.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.





ZigBee can address a wide range of wireless needs.
It was designed primarily for monitoring and control.
Monitoring refers to looking at a wide range of
physical conditions, especially temperature, humidity,
pressure, the presence of light, speed, and position
information.
Control refers to the sending of command signals to
initiate some action.
Typically commands are used to turn things off and
on, such as lights, motors, solenoids, relays, and other
devices.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.

Popular applications of ZigBee include:
 Monitoring and controlling lights;
 Heating, ventilating, and air conditioning (HVAC)






systems in large buildings;
Industrial monitoring and control in factories,
chemical plants, and manufacturing operations.
Automatic electric and gas meter reading.
Medical uses, such as wireless patient monitoring.
Automotive sensor systems.
Military battlefield monitoring.
Consumer applications such as home monitoring and
control, remote control of other objects, and security.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.



Metropolitan-area networks (MANs) are
primarily fiber-optic networks, most often
SONET rings, that connect enterprise LANs
to WANs or the Internet backbone.
Another typical MAN is a local cable TV
network.
A new wireless contender for metropolitanarea networking is known as WiMAX. It is
defined by the IEEE 802.16 standard.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.



It was developed to provide a wireless
alternative to consumers for broadband
Internet connections.
These connections are now dominated by
cable TV and DSL, but with the new WiMAX
standard, wireless Internet service providers
(WISPs) may soon be offering wireless
broadband connections.
The primary standard is known as IEEE
802.16-2004 or 802.16d.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.



Perhaps the most widespread wireless
system uses infrared (IR) light for shortdistance data communication.
The most widely used is the wireless remote
control on TV sets, VCRs, and DVD players
and on most audio CD stereo systems.
Infrared has also been used for wireless LANs
and PANs.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
TV Remote Control
 Almost every TV set sold these days, regardless of
size or cost, has a wireless remote control.
 Other consumer electronic products have remote
controls including VCRs, cable TV converters, CD
and DVD players, stereo audio systems, and some
ordinary radios.
 Generic remote controls are available to hook up
to any device that you wish to control remotely.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
TV Remote Control
 All remote control devices work on the same
principle.
 A small handheld battery-powered unit transmits
a serial digital code via an IR beam to a receiver
that decodes it and carries out the specific action
defined by the code.
 A TV remote control is one of the more
sophisticated of these controls, for it requires
many codes to perform volume control, channel
selection, and other functions.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
TV Remote Control
 The keyboard is a matrix of single-pole single-throw
(SPST) pushbuttons.
 The row and column connections are made to a
keyboard encoder circuit inside the IC.
 When a key is depressed, the pulses from one of the
column outputs are connected to one of the row
inputs.
 The encoder circuit converts this input to a unique
binary code representing a number for channel
selection or some function such as volume control.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
TV Remote Control
 The serial output is generated by the shift register as




data is shifted out.
A standard nonreturn to zero (NRZ) serial code is
generated and applied to a serial encoder.
The serial bit stream turns a higher-frequency pulse
source off and on.
The pulses modulate the IR light source by turning it
off and on.
The IR source is usually one or more IR LEDs. Two or
more LEDs are used to ensure a sufficient level of IR
radiation to the receiver in the TV set.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Figure 21-5: IR TV remote control transmitter.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
TV Remote Control
 In an IR receiver, the PIN IR photodiode is mounted on




the front of the TV set, where it picks up the IR signal
from the transmitter.
Two or more high-gain amplifiers boost the signal
level.
The incoming pulses are detected, shaped, and
converted to the original serial data train.
This serial data is read by the control microcomputer
that is usually part of the TV receiver.
The microcontroller inputs and decodes the incoming
signal and issues output control signals to all other
circuits.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
IR PANs
 Besides remote control, the primary application
for IR data communication is in short-distance
links between computers, computers and printers,
or ad hoc PANs.
 Distance links are typically up to 1 m, however
under some conditions, the distance can be
extended to 9 m.
 There must be a clear line of sight between the
transmitter and receiver.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Figure 21-8: Common applications for IR data communication.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
IR PANs
 An IR transceiver connects to interface circuitry in
the PC or PDA.
 The interface is typically a small embedded
controller inside the computer or PDA.
 The encoder puts the serial digital data from the
PC or PDA into the proper format for
transmission.
 A high-current bipolar transistor or MOSFET
drives one or more IR LEDs.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
IR PANs
 The receiver consists of the PIN diode that picks up
the IR light from a nearby transmitter.
 The signal is amplified and shaped and then sent to
the decoder, which recovers the original data.
 Although many laptops and PDAs have a built-in
transceiver, their use is often restricted by this need
for line of sight.
 A better arrangement is a transceiver dongle which
consists of a cable attached to the interface in the PC
or PDA and to the movable dongle containing the
LED and PIN diode.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Figure 21-8: IR wireless LAN transceiver.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.



Another growing wireless technique is radio
frequency identification (RFID).
RFID uses thin, inexpensive tags or labels
containing passive radio circuits that can be
queried by a remote wireless interrogation
unit.
The tags are attached to any item that is to
be monitored, tracked, accessed, located, or
otherwise identified.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
RFID tags are widely used in inventory control,
container and parcel shipping, capital equipment
and other asset management, baggage
handling, and manufacturing and production
line tracking.
 Other applications for RFID tags are personnel
security checking and access, animal tracking,
and theft prevention, automatic toll collection
and parking access for vehicles.
 As the technology develops, prices drop and
new applications are being discovered.

Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.



The tag is a very thin label-like device into
which is embedded a simple passive singlechip radio transceiver and antenna.
The chip also contains a memory that stores a
digital ID code unique to the tagged item.
For the item to be identified, it must pass by
the interrogation or reader unit, or the reader
must physically go to a location near the
item.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.



The reader unit sends out a radio signal that
may travel from a few inches up to no more
than a hundred feet or so.
The radio signal is strong enough to activate
the tag.
The tag rectifies and filters the RF signal into
direct current that operates the transceiver.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.


This activates a low-power transmitter that
sends a signal back to the interrogator unit
along with its embedded ID code.
The reader checks its attached computer,
where it notes the presence of the item and
may perform other processing tasks
associated with the application.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Figure 21-10: Basic concept and components of an RFID system.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Figure 21-12: RFID tag configurations.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.




The most recent new RFID standard is called Gen 2 for
second generation.
The standard is under the auspices of EPCGlobal, the
organization that also standardizes the Electronic
Product Code (EPC) used on all tagged items.
A key benefit of the new standard is that it is designed
to read multiple tags faster. Tag read rates as high as
1500 tags per second are possible.
The Gen 2 tags can operate reliably in an environment
with multiple readers transmitting and receiving
simultaneously.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Near-Field Communications
 One of the newest forms of wireless is a version of
RFID called near-field communications (NFC).
 It is an ultrashort-range wireless whose range is
rarely more than a few inches.
 It is a technology used in smart cards and cell
phones to pay for purchases or gain admittance to
some facilities.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.



Perhaps the newest and most unusual form of
wireless is known as ultrawideband (UWB)
wireless.
There are two basic forms of UWB: the original
version based on very narrow impulses, and the
newer kind based on OFDM.
The original UWB, also known as impulse,
baseband, or carrierless wireless, transmits data
in the form of very short pulses, typically less
than 1 ns.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Impulse UWB Hardware
 The UWB transmitter circuits use BPSK to generate




pulses which are applied directly to the antenna.
The receiver amplifies the incoming signal and then
applies it to a correlator consisting of a multiplier,
where it is multiplied by a stream of coded pulses
similar to those transmitted.
If the multiplier output exceeds a specific level, it is
considered to be detected and recovered.
The recognized signal is then demodulated into the
original data.
Broadband antennas are used for UWB.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Multiband OFDM UWB
 The newest form of UWB is called multiband OFDM or
MB-OFDM UWB.
 This form of UWB divides the lower end of the
assigned spectrum into three 528-MHz-wide
channels, extending from 3.168 to 4.952 GHz.
 Each band is designed to hold an OFDM data signal.
 There are 128 carriers per band: 100 carry the data; 12
are used as pilot carriers; the remaining ones serve as
guard bands.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Multiband OFDM UWB
 The signal is divided up among the carriers, and
each is modulated by BPSK or QPSK depending
on the data speed selected.
 The system permits a wide range of data rates
from about 53 to 480 Mbps.
 Implementation of an OFDM UWB transceiver is
just like that of any OFDM device.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Advantages and Disadvantages of UWB
 UWB offers many benefits to radar, imaging, and
communication applications:
▪ Superior resolution in radar and imaging.
▪ Immunity to multipath propagation effects.
▪ Higher data rates than are possible with other wireless
technologies.
▪ License-free operation
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Advantages and Disadvantages of UWB
 No interference to other signals using the same
frequency band. UWB signals appear as random noise
to conventional radios.
 Power-efficient. Extremely low-power operation.
Peak power levels are in the milliwatt region, and
average power in microwatts.
▪ This low power severely limits the range of operation.
 Simple circuitry, most of which can be integrated in
standard CMOS.
 Potentially low cost.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Primary Application of UWB
 The primary application of impulse UWB to date has




been in military radar.
UWB radar is used by fire, emergency, and police
personnel to see through walls and doors.
Medical versions permit body imaging for diagnosis.
Low-cost, short-range UWB radars that can be used in
cars and trucks for collision avoidance, automatic
braking, improved air bag deployment, and
suspension systems are under development.
Target markets for UWB include computer peripherals
and wirelessly connecting video equipment.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.
Copyright © 2016 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.