ESAT Forouzan - Chapter 5: Analog Transmission Flashcards
ASK, PSK, FSK nad QAM are examples of __________ modulation.
a. Digital-to-analog
b. Digital-to-analog
c. Analog-to-analog
d. Analog-to-digital
a. Digital-to-analog
AM and FM are examples of ___________ modulation.
a. Digital-to-analog
b. Digital-to-analog
c. Analog-to-analog
d. Analog-to-digital
c. Analog-to-analog
In QAM, both phase and ____________ of a carrier frequency are varied.
a. Amplitude
b. Frequency
c. Bit rate
d. Baud rate
a. Amplitude
Which of the following is most affected by noise?
a. PSK
b. ASK
c. FSK
d. QAM
b. ASK
If the baud rate is 400 for a 4-PSK signal, the bit rate is _________ bps.
a. 100
b. 400
c. 800
d. 1600
c. 800
If the bit rate for an ASK signal is 1200 bps, the baud rate is __________.
a. 300
b. 400
c. 600
d. 1200
d. 1200
If the bit rate for an FSK signal is 1200 bps, the baud rate is __________.
a. 300
b. 400
c. 600
d. 1200
d. 1200
If the bit rate for a QAM signal is 3000 bps and a signal unit is represented by a tribit, what is the baud rate?
a. 300
b. 400
c. 1000
d. 1200
c. 1000
If the baud rate for a QAM signal is 3000 and a signal unit is represented by a tribit, what is the bit rate?
a. 300
b. 400
c. 1000
d. 9000
d. 9000
If the baud rate for a QAM signal is 1800 and the bit rate is 9000, how many bits are there per signal unit?
a. 3
b. 4
c. 5
d. 6
c. 5
In 16-QAM, there are 16 __________.
a. Combination of phase and amplitude
b. Amplitudes
c. Phases
d. Bps
a. Combination of phase and amplitude
Which modulation technique involves tribits, eight different phase shifts, and one amplitude?
a. FSK
b. 8-PSK
c. ASK
d. 4-PSK
b. 8-PSK
Given an AM radio signal with a bandwidth of 10 KHz and the highest-frequency component at 705 KHz, what is the frequency of the carrier signal?
a. 700 KHz
b. 705 KHz
c. 710 KHz
d. Cannot be determined from given information
a. 700 KHz
A modulated signal is formed by ________.
a. Changing the modulating signal by the carrier wave
b. Changing the carrier wave by the modulating signal
c. Quantization of the source data
d. Sampling at the Nyquist frequency
b. Changing the carrier wave by the modulating signal
If FCC regulations are followed, the carrier frequencies of adjacent AM radio station are _________ apart.
a. 5 KHz
b. 10 KHz
c. 200 KHz
d. 530 KHz
b. 10 KHz
If FCC regulations are followed, ___________ potential FM stations are theoretically possible in a given area.
a. 50
b. 100
c. 133
d. 150
a. 50
When an ASK signal is decomposed, the result is _____________.
a. Always one sine wave
b. Always two sine waves
c. An infinite number of sine waves
d. None of the above
c. An infinite number of sine waves
The bandwidth of an FM signal requires 10 times the bandwidth of the __________ signal.
a. Carrier
b. Modulating
c. Bipolar
d. Sampling
b. Modulating
Modulation of an analog signal can be accomplished through changing the ______ of the carrier signal.
a. Amplitude
b. Frequency
c. Phase
d. Any of the above
d. Any of the above
For a telephone line, the bandwidth for voice is usually _________ the bandwidth for data.
a. Equivalent to
b. Less than
c. Greater than
d. Twice
c. Greater than
For a given bit rate, the minimum bandwidth for ASK is ______ the minimum bandwidth for FSK.
a. Equivalent to
b. Less than
c. Greater than
d. Twice
b. Less than
As the bit rate of an FSK signal increases, the bandwidth ___________.
a. Decreases
b. Increases
c. Remains the same
d. Doubles
b. Increases
For FSK, as the difference between the two carrier frequencies increases, the bandwidth ________.
a. Decreases
b. Increases
c. Remains the same
d. Halves
b. Increases
Which ITU-T modems standard uses trellis coding
a. V.32
b. V.33
c. V.34
d. (a) and (b)
a. V.32
In trellis coding the number of data bits is _________ the number of transmitted bits.
a. Equal to
b. Less than
c. More than
d. Double that of
b. Less than
What is the object of trellis coding?
a. To narrow the bandwidth
b. To simplify modulation
c. To increases the data rate
d. To reduce the error rate
d. To reduce the error rate
The bit rate always equal the baud rate in which type of signal?
a. FSK
b. QAM
c. 4-PSK
d. All the above
a. FSK
A modulator converts a(n) _________ signal to a(n) ____________ signal.
a. Digital; analog
b. Analog; digital
c. PSK; FSK
d. FSK; PSK
b. Analog; digital
A 56K modem can download at a rate of ___________ Kbps and upload at a rate of ______________ Kbps.
a. 33.6; 33.6
b. 33.6; 56.3
c. 56.6; 33.6
d. 56.6; 56.6
c. 56.6; 33.6