QUESTION 11

Identify the correct grouping of line coding techniques (i.e., mapping logical 1s and 0s directly to an electrical baseband signal).

a. ASK, FSK, PSK

b. ASK, QAM, NRZ

c. NRZ, Bipolar AMI, Manchester

d. AM, FM, PM

QUESTION 12:4B5B differs from line coding techniques in that is ensures that strings of consecutive 1s and 0s do not exist prior to being line coded. Select the correct statement(s) regarding 4B5B.

a. since 4B5B eliminates long string of logical 1s and 0s, simpler line coding techniques such as NRZ can be used.

b. since one bit out of every five bits sent is not real information, the data link suffers from a 1/5 or 20% overhead cost (i.e., reduction in data throughput

c. only 80% of the data sent using 4B5B is real information

d. all of the above are correct statements

QUESTION 13:Select the line coding technique in which the signal is sampled in the center of the clock pulse, and where a voltage transition essentially guarantees signal changes despite the transmission of long strings of logical 1s or 0s.

a. NRZ

b. Bipolar AMI

c. Manchester

d. B8ZS

QUESTION 14: Analog information can be converted into digital data using techniques such as PCM (pulse code modulation). Select the correct statement(s).

a. in order to convert an analog signal that consists of an infinite number of values, it must be sampled using the Nyquist sampling theorem

b. digitized analog signals always experience quantization loss

c. signal aliasing is experienced when sampling falls under the recommended Nyquist sampling rate

d. all of the above are correct

QUESTION 15:During the ADC process, failure to follow the Nyquist sampling theorem will result in a poor digital representation of the digitized analog signal. The result is signal aliasing.

True False

QUESTION 16:When digitizing an analog signal, quantization errors will always be present regardless of bit-depth used.

True False

QUESTION 17: Digital compression techniques can be classified as either lossless or lossy.

True False

QUESTION 18: What does a BER of 10-7 mean?

a. there will be no errors during transmission since the BER is so low

b. there is a probability of one error for every 10,000,000 bits transmitted

c. does not mean anything unless associated with a transmission data rate (bit rate)

d. None of the above