Question 1

The point where the communications carrier brings in service to a facility is called the:

Accepted Answer

A)  point of presence 
B)  patch line 
C)  CSU/DSU 
D)  termination line 
A)  point of presence 
B)  patch line 
C)  CSU/DSU 
D)  termination line A

Question 2

A cell relay technique designed for voice, data and video traffic and considered to be an evolution of packet switching is:

Accepted Answer

A)  POP 
B)  ATM 
C)  ACR-3 
D)  MPEG-2 
A)  POP 
B)  ATM 
C)  ACR-3 
D)  MPEG-2 B

Question 3

A technique used to transport data from multiple users over the same data channel is:

Accepted Answer

A)  Fractional T1 
B)  FDMA 
C)  TDMA 
D)  CDMA 
A)  Fractional T1 
B)  FDMA 
C)  TDMA 
D)  CDMA C

Question 4

What is the coding efficiency if a language has 18 letters in its alphabet?

Accepted Answer

A)  95% 
B)  87% 
C)  83% 
D)  none of the above 
A)  95% 
B)  87% 
C)  83% 
D)  none of the above

Question 5

A two-tone amplitude modulation system uses 400 Hz for a "one" and 550 Hz for a "zero" and a carrier frequency of 9.35 MHz. The required bandwidth for this communication channel is:

Accepted Answer

A)  400 Hz. 
B)  1100 Hz 
C)  550 Hz 
D)  950 Hz 
E)  800 Hz 
A)  400 Hz. 
B)  1100 Hz 
C)  550 Hz 
D)  950 Hz 
E)  800 Hz

Question 6

Which of the following can be used to generate PWM?

Accepted Answer

A)  PTM 
B)  PAM 
C)  PCM 
D)  PPM 
A)  PTM 
B)  PAM 
C)  PCM 
D)  PPM

Question 7

Which is not an advantage of digital data communication systems over analog communications?

Accepted Answer

A)  They eliminate errors in the received signal 
B)  They have narrower bandwidths 
C)  They have superior noise performance 
D)  They have the ability to process the signal at the transmitter and receiver using digital signal processing techniques 
A)  They eliminate errors in the received signal 
B)  They have narrower bandwidths 
C)  They have superior noise performance 
D)  They have the ability to process the signal at the transmitter and receiver using digital signal processing techniques

Question 8

An example of a packet switching network designed to carry data traffic over a public data network is:

Accepted Answer

A)  IEEE 802.5 
B)  frame relay 
C)  IEEE 802.3 
D)  none of the above 
A)  IEEE 802.5 
B)  frame relay 
C)  IEEE 802.3 
D)  none of the above

Question 9

The major advantage of a delta modulator over PCM circuitry is its

Accepted Answer

A)  greater resistance to any error produced by noise 
B)  bandwidth characteristics 
C)  frequency response of the intelligence signal 
D)  simplicity in design 
A)  greater resistance to any error produced by noise 
B)  bandwidth characteristics 
C)  frequency response of the intelligence signal 
D)  simplicity in design

Question 10

A certain language has 18 letters in its alphabet. How many bits are required to represent the 18 letters?

Accepted Answer

A)  5 
B)  6.1 
C)  4.2 
D)  3.8 
A)  5 
B)  6.1 
C)  4.2 
D)  3.8

Question 11

The T1 data rate is:

Accepted Answer

A)  512 kbps 
B)  56 kbps 
C)  1.544 Mbps 
D)  44.736 Mbps 
A)  512 kbps 
B)  56 kbps 
C)  1.544 Mbps 
D)  44.736 Mbps

Question 12

Another name for delta modulation is

Accepted Answer

A)  pulse modulation 
B)  codec 
C)  slope modulation 
D)  all of the above 
A)  pulse modulation 
B)  codec 
C)  slope modulation 
D)  all of the above

Question 13

Which of the following is not a major protocol function?

Accepted Answer

A)  character insertion 
B)  line control 
C)  flow control 
D)  framing 
A)  character insertion 
B)  line control 
C)  flow control 
D)  framing

Question 14

In what type of transmission is bit rate and baud rate the same?

Accepted Answer

A)  hexadecimal transmission 
B)  binary transmission 
C)  analog 
D)  pulse amplitude modulation 
A)  hexadecimal transmission 
B)  binary transmission 
C)  analog 
D)  pulse amplitude modulation

Question 15

A term used to indicate that only a portion of the data bandwidth of a T1 line is being used is:

Accepted Answer

A)  Companded T1 
B)  Multiplexed T1 
C)  Fractional T1 
D)  T1/2 
A)  Companded T1 
B)  Multiplexed T1 
C)  Fractional T1 
D)  T1/2

Question 16

Baseband analog data channels are characterized by:

Accepted Answer

A)  the fact that a coder has converted the digital intelligence into a specific coding format for subsequent transmission. 
B)  the fact that a modem has converted the intelligence to an analog signal for use on an analog channel 
C)  the fact that the intelligence is being transmitted at its base frequencies; no modulation to another frequency range has occurred. 
D)  the fact that a modulator has converted the analog intelligence into a modulated analog signal on another frequency range 
A)  the fact that a coder has converted the digital intelligence into a specific coding format for subsequent transmission. 
B)  the fact that a modem has converted the intelligence to an analog signal for use on an analog channel 
C)  the fact that the intelligence is being transmitted at its base frequencies; no modulation to another frequency range has occurred. 
D)  the fact that a modulator has converted the analog intelligence into a modulated analog signal on another frequency range

Question 17

The most desired pulse modulation scheme is:

Accepted Answer

A)  pulse position modulation (PPM). 
B)  pulse width modulation (PWM). 
C)  pulse frequency modulation (PFM). 
D)  pulse amplitude modulation (PAM). 
A)  pulse position modulation (PPM). 
B)  pulse width modulation (PWM). 
C)  pulse frequency modulation (PFM). 
D)  pulse amplitude modulation (PAM).

Question 18

An advantage of PPM over PWM is

Accepted Answer

A)  its frequency response of the intelligence signal 
B)  its greater resistance to any error produced by noise 
C)  its simplicity in design 
D)  its limited bandwidth 
A)  its frequency response of the intelligence signal 
B)  its greater resistance to any error produced by noise 
C)  its simplicity in design 
D)  its limited bandwidth

Question 19

A digital transmission has an error probability of 1 x 10^-5 and is 1 x 10^8 bits long. Its BER is:

Accepted Answer

A)  1 x 10^-3 
B)  1 x 10^-8 
C)  1 x 10^-5 
D)  1 x 10^-4 
A)  1 x 10^-3 
B)  1 x 10^-8 
C)  1 x 10^-5 
D)  1 x 10^-4

The point where the communications carrier brings in service to a facility is called the:

A cell relay technique designed for voice, data and video traffic and considered to be an evolution of packet switching is:

A technique used to transport data from multiple users over the same data channel is:

What is the coding efficiency if a language has 18 letters in its alphabet?

A two-tone amplitude modulation system uses 400 Hz for a "one" and 550 Hz for a "zero" and a carrier frequency of 9.35 MHz. The required bandwidth for this communication channel is:

Which of the following can be used to generate PWM?

Which is not an advantage of digital data communication systems over analog communications?

An example of a packet switching network designed to carry data traffic over a public data network is:

The major advantage of a delta modulator over PCM circuitry is its

A certain language has 18 letters in its alphabet. How many bits are required to represent the 18 letters?

The T1 data rate is:

Another name for delta modulation is

Which of the following is not a major protocol function?

In what type of transmission is bit rate and baud rate the same?

A term used to indicate that only a portion of the data bandwidth of a T1 line is being used is:

Baseband analog data channels are characterized by:

The most desired pulse modulation scheme is:

An advantage of PPM over PWM is

A digital transmission has an error probability of 1 x 10^-5 and is 1 x 10^8 bits long. Its BER is:

Introductory Topics

Amplitude Modulation: Transmission

Amplitude Modulation: Reception

Single-Sideband Communications

Frequency Modulation: Transmission

Frequency Modulation: Reception

Communications Techniques

Digital Communications: Coding Techniques

Wireless Digital Communications

Network Communications

Transmission Lines

Wave Propagation

Antennas

Waveguides and Radar

Microwaves and Lasers

Television

Fiber Optics

Filters

Exam 9: Wired Digital Communications

The point where the communications carrier brings in service to a facility is called the:

A cell relay technique designed for voice, data and video traffic and considered to be an evolution of packet switching is:

A technique used to transport data from multiple users over the same data channel is:

What is the coding efficiency if a language has 18 letters in its alphabet?

A two-tone amplitude modulation system uses 400 Hz for a "one" and 550 Hz for a "zero" and a carrier frequency of 9.35 MHz. The required bandwidth for this communication channel is:

Which of the following can be used to generate PWM?

Which is not an advantage of digital data communication systems over analog communications?

An example of a packet switching network designed to carry data traffic over a public data network is:

The major advantage of a delta modulator over PCM circuitry is its

A certain language has 18 letters in its alphabet. How many bits are required to represent the 18 letters?

The T1 data rate is:

Another name for delta modulation is

Which of the following is not a major protocol function?

In what type of transmission is bit rate and baud rate the same?

A term used to indicate that only a portion of the data bandwidth of a T1 line is being used is:

Baseband analog data channels are characterized by:

The most desired pulse modulation scheme is:

An advantage of PPM over PWM is

A digital transmission has an error probability of 1 x 10^-5 and is 1 x 10^8 bits long. Its BER is:

Introductory Topics

Amplitude Modulation: Transmission

Amplitude Modulation: Reception

Single-Sideband Communications

Frequency Modulation: Transmission

Frequency Modulation: Reception

Communications Techniques

Digital Communications: Coding Techniques

Wireless Digital Communications

Network Communications

Transmission Lines

Wave Propagation

Antennas

Waveguides and Radar

Microwaves and Lasers

Television

Fiber Optics

Filters