and automation technologies increasingly shape various industries, the ethical and legal
dilemmas associated with them are becoming more pronounced. The potential for AI to
significantly alter the workforce, decision-making, and even the human experience brings about
complex challenges.#### 12.1 **Bias and Discrimination in AI Systems**AI and machine
learning systems are increasingly being employed in decision-making processes, from hiring
practices to criminal justice sentencing and credit scoring. A major ethical concern is the
potential for bias in these systems, as algorithms may inadvertently perpetuate existing
inequalities. If AI models are trained on biased data (e.g., reflecting historical discrimination),
they can reproduce and even amplify these biases, leading to discriminatory outcomes.From a
SOLUTIONS MANUAL
WIRELESS COMMUNICATIONS AND
NETWORKS
SECOND EDITION
WILLIAM STALLINGS
,TABLE OF CONTENTS
Chapter 2: Transmission Fundamentals .......................................................................5
Chapter 3: Communication Networks..........................................................................8
Chapter 4: Protocols and the TCP/IP Suite ............................................................... 14
Chapter 5: Antennas and Propagation .......................................................................17
Chapter 6: Signal Encoding Techniques .....................................................................22
Chapter 7: Spread Spectrum ........................................................................................ 28
Chapter 8: Coding and Error Control .........................................................................34
Chapter 9: Satellite Communications..........................................................................44
Chapter 10: Cellular Wireless Networks ......................................................................48
Chapter 11: Cordless Systems and Wireless Local Loop ...........................................54
Chapter 12: Mobile IP and Wireless Access Protocol ................................................. 56
Chapter 13: Wireless LAN Technology ........................................................................59
Chapter 14: Wi-Fi and the IEEE 802.11 Wireless LAN Standard .............................. 61
Chapter 15: Bluetooth and IEEE 802.15 ........................................................................65
and automation technologies increasingly shape various industries, the ethical and legal
dilemmas associated with them are becoming more pronounced. The potential for AI to
significantly alter the workforce, decision-making, and even the human experience brings
about complex challenges.#### 12.1 **Bias and Discrimination in AI Systems**AI and machine
learning systems are increasingly being employed in decision-making processes, from hiring
practices to criminal justice sentencing and credit scoring. A major ethical concern is the
potential for bias in these systems, as algorithms may inadvertently perpetuate existing
inequalities. If AI models are trained on biased data (e.g., reflecting historical discrimination),
they can reproduce and even amplify these biases, leading to discriminatory outcomes.From
a
, CHAPTER 2
TRANSMISSION FUNDAMENTALS
A NSWERS TO Q UESTIONS
and automation technologies increasingly shape various industries, the ethical and legal
dilemmas associated with them are becoming more pronounced. The potential for AI to
significantly alter the workforce, decision-making, and even the human experience brings
about complex challenges.#### 12.1 **Bias and Discrimination in AI Systems**AI and
machine learning systems are increasingly being employed in decision-making processes,
from hiring practices to criminal justice sentencing and credit scoring. A major ethical
concern is the potential for bias in these systems, as algorithms may inadvertently
perpetuate existing inequalities. If AI models are trained on biased data (e.g., reflecting
historical discrimination), they can reproduce and even amplify these biases, leading to
discriminatory outcomes.From a
2.1 A continuous or analog signal is one in which the signal intensity varies in a
smooth fashion over time while a discrete or digital signal is one in which the signal
intensity maintains one of a finite number of constant levels for some period of time
and then changes to another constant level.
2.2 Amplitude, frequency, and phase are three important characteristics of a periodic
signal.
2.3 2π radians.
2.4 The relationship is f = v, where is the wavelength, f is the frequency, and v is the
speed at which the signal is traveling.
2.5 The spectrum of a signal consists of the frequencies it contains; the bandwidth of a
signal is the width of the spectrum.
2.6 Attenuation is the gradual weakening of a signal over distance.
2.7 The rate at which data can be transmitted over a given communication path, or
channel, under given conditions, is referred to as the channel capacity.
2.8 Bandwidth, noise, and error rate affect channel capacity.
2.9 With guided media, the electromagnetic waves are guided along an enclosed
physical path, whereas unguided media provide a means for transmitting
electromagnetic waves through space, air, or water, but do not guide them.
2.10 Point-to-point microwave transmission has a high data rate and less attenuation
than twisted pair or coaxial cable. It is affected by rainfall, however, especially
above 10 GHz. It is also requires line of sight and is subject to interference from
, other microwave transmission, which can be intense in some places.
2.11 Direct broadcast transmission is a technique in which satellite video signals are
transmitted directly to the home for continuous operation.
2.12 A satellite must use different uplink and downlink frequencies for continuous
operation in order to avoid interference.
2.13 Broadcast is omnidirectional, does not require dish shaped antennas, and the
antennas do not have to be rigidly mounted in precise alignment.
2.14 Multiplexing is cost-effective because the higher the data rate, the more
cost-effective the transmission facility.
2.15 Interference is avoided under frequency division multiplexing by the use of guard
bands, which are unused portions of the frequency spectrum between
subchannels.
2.16 A synchronous time division multiplexer interleaves bits from each signal and
takes turns transmitting bits from each of the signals in a round-robin fashion.
and automation technologies increasingly shape various industries, the ethical and legal
dilemmas associated with them are becoming more pronounced. The potential for AI to
significantly alter the workforce, decision-making, and even the human experience brings
about complex challenges.#### 12.1 **Bias and Discrimination in AI Systems**AI and machine
learning systems are increasingly being employed in decision-making processes, from hiring
practices to criminal justice sentencing and credit scoring. A major ethical concern is the
potential for bias in these systems, as algorithms may inadvertently perpetuate existing
inequalities. If AI models are trained on biased data (e.g., reflecting historical discrimination),
they can reproduce and even amplify these biases, leading to discriminatory outcomes.From
a
A NSWERS TO PROBLEMS
2.1 Period = 1/1000 = 0.001 s = 1 ms.
2.2 a. sin (2ft – ) + sin (2ft + ) = 2 sin (2ft + ) or 2 sin (2ft – ) or - 2 sin (2ft)
b. sin (2ft) + sin (2ft – ) = 0.
2.3
N C D E F G A B C
F 264 297 330 352 396 440 495 528
D 33 33 22 44 44 55 33
W 1.25 1.11 1 0.93 0.83 0.75 0.67 0.63
N = note; F = frequency (Hz); D = frequency difference; W = wavelength (m)
2.4 2 sin(4t + ); A = 2, f = 2, =
2.5 (1 + 0.1 cos 5t) cos 100t = cos 100t + 0.1 cos 5t cos 100t. From the trigonometric
identity cos a cos b = (1/2)(cos(a + b) + cos(a – b)), this equation can be rewritten as
the linear combination of three sinusoids:
cos 100t + 0.05 cos 105t + 0.05 cos 95t
dilemmas associated with them are becoming more pronounced. The potential for AI to
significantly alter the workforce, decision-making, and even the human experience brings about
complex challenges.#### 12.1 **Bias and Discrimination in AI Systems**AI and machine
learning systems are increasingly being employed in decision-making processes, from hiring
practices to criminal justice sentencing and credit scoring. A major ethical concern is the
potential for bias in these systems, as algorithms may inadvertently perpetuate existing
inequalities. If AI models are trained on biased data (e.g., reflecting historical discrimination),
they can reproduce and even amplify these biases, leading to discriminatory outcomes.From a
SOLUTIONS MANUAL
WIRELESS COMMUNICATIONS AND
NETWORKS
SECOND EDITION
WILLIAM STALLINGS
,TABLE OF CONTENTS
Chapter 2: Transmission Fundamentals .......................................................................5
Chapter 3: Communication Networks..........................................................................8
Chapter 4: Protocols and the TCP/IP Suite ............................................................... 14
Chapter 5: Antennas and Propagation .......................................................................17
Chapter 6: Signal Encoding Techniques .....................................................................22
Chapter 7: Spread Spectrum ........................................................................................ 28
Chapter 8: Coding and Error Control .........................................................................34
Chapter 9: Satellite Communications..........................................................................44
Chapter 10: Cellular Wireless Networks ......................................................................48
Chapter 11: Cordless Systems and Wireless Local Loop ...........................................54
Chapter 12: Mobile IP and Wireless Access Protocol ................................................. 56
Chapter 13: Wireless LAN Technology ........................................................................59
Chapter 14: Wi-Fi and the IEEE 802.11 Wireless LAN Standard .............................. 61
Chapter 15: Bluetooth and IEEE 802.15 ........................................................................65
and automation technologies increasingly shape various industries, the ethical and legal
dilemmas associated with them are becoming more pronounced. The potential for AI to
significantly alter the workforce, decision-making, and even the human experience brings
about complex challenges.#### 12.1 **Bias and Discrimination in AI Systems**AI and machine
learning systems are increasingly being employed in decision-making processes, from hiring
practices to criminal justice sentencing and credit scoring. A major ethical concern is the
potential for bias in these systems, as algorithms may inadvertently perpetuate existing
inequalities. If AI models are trained on biased data (e.g., reflecting historical discrimination),
they can reproduce and even amplify these biases, leading to discriminatory outcomes.From
a
, CHAPTER 2
TRANSMISSION FUNDAMENTALS
A NSWERS TO Q UESTIONS
and automation technologies increasingly shape various industries, the ethical and legal
dilemmas associated with them are becoming more pronounced. The potential for AI to
significantly alter the workforce, decision-making, and even the human experience brings
about complex challenges.#### 12.1 **Bias and Discrimination in AI Systems**AI and
machine learning systems are increasingly being employed in decision-making processes,
from hiring practices to criminal justice sentencing and credit scoring. A major ethical
concern is the potential for bias in these systems, as algorithms may inadvertently
perpetuate existing inequalities. If AI models are trained on biased data (e.g., reflecting
historical discrimination), they can reproduce and even amplify these biases, leading to
discriminatory outcomes.From a
2.1 A continuous or analog signal is one in which the signal intensity varies in a
smooth fashion over time while a discrete or digital signal is one in which the signal
intensity maintains one of a finite number of constant levels for some period of time
and then changes to another constant level.
2.2 Amplitude, frequency, and phase are three important characteristics of a periodic
signal.
2.3 2π radians.
2.4 The relationship is f = v, where is the wavelength, f is the frequency, and v is the
speed at which the signal is traveling.
2.5 The spectrum of a signal consists of the frequencies it contains; the bandwidth of a
signal is the width of the spectrum.
2.6 Attenuation is the gradual weakening of a signal over distance.
2.7 The rate at which data can be transmitted over a given communication path, or
channel, under given conditions, is referred to as the channel capacity.
2.8 Bandwidth, noise, and error rate affect channel capacity.
2.9 With guided media, the electromagnetic waves are guided along an enclosed
physical path, whereas unguided media provide a means for transmitting
electromagnetic waves through space, air, or water, but do not guide them.
2.10 Point-to-point microwave transmission has a high data rate and less attenuation
than twisted pair or coaxial cable. It is affected by rainfall, however, especially
above 10 GHz. It is also requires line of sight and is subject to interference from
, other microwave transmission, which can be intense in some places.
2.11 Direct broadcast transmission is a technique in which satellite video signals are
transmitted directly to the home for continuous operation.
2.12 A satellite must use different uplink and downlink frequencies for continuous
operation in order to avoid interference.
2.13 Broadcast is omnidirectional, does not require dish shaped antennas, and the
antennas do not have to be rigidly mounted in precise alignment.
2.14 Multiplexing is cost-effective because the higher the data rate, the more
cost-effective the transmission facility.
2.15 Interference is avoided under frequency division multiplexing by the use of guard
bands, which are unused portions of the frequency spectrum between
subchannels.
2.16 A synchronous time division multiplexer interleaves bits from each signal and
takes turns transmitting bits from each of the signals in a round-robin fashion.
and automation technologies increasingly shape various industries, the ethical and legal
dilemmas associated with them are becoming more pronounced. The potential for AI to
significantly alter the workforce, decision-making, and even the human experience brings
about complex challenges.#### 12.1 **Bias and Discrimination in AI Systems**AI and machine
learning systems are increasingly being employed in decision-making processes, from hiring
practices to criminal justice sentencing and credit scoring. A major ethical concern is the
potential for bias in these systems, as algorithms may inadvertently perpetuate existing
inequalities. If AI models are trained on biased data (e.g., reflecting historical discrimination),
they can reproduce and even amplify these biases, leading to discriminatory outcomes.From
a
A NSWERS TO PROBLEMS
2.1 Period = 1/1000 = 0.001 s = 1 ms.
2.2 a. sin (2ft – ) + sin (2ft + ) = 2 sin (2ft + ) or 2 sin (2ft – ) or - 2 sin (2ft)
b. sin (2ft) + sin (2ft – ) = 0.
2.3
N C D E F G A B C
F 264 297 330 352 396 440 495 528
D 33 33 22 44 44 55 33
W 1.25 1.11 1 0.93 0.83 0.75 0.67 0.63
N = note; F = frequency (Hz); D = frequency difference; W = wavelength (m)
2.4 2 sin(4t + ); A = 2, f = 2, =
2.5 (1 + 0.1 cos 5t) cos 100t = cos 100t + 0.1 cos 5t cos 100t. From the trigonometric
identity cos a cos b = (1/2)(cos(a + b) + cos(a – b)), this equation can be rewritten as
the linear combination of three sinusoids:
cos 100t + 0.05 cos 105t + 0.05 cos 95t
