Key Topic 83: Coding and Multiplexing

Question 1

3-83M1: What is a CODEC?

A. A device to read Morse code.
B. A computer operated digital encoding compandor.
C. A coder/decoder IC or circuitry that converts a voice signal into a predetermined digital format for encrypted transmission.
D. A voice amplitude compression chip.

Answer 1

C. A coder/decoder IC or circuitry that converts a voice signal into a predetermined digital format for encrypted transmission.

Question 2

3-83M2: The GSM (Global System for Mobile Communications) uses what type of CODEC for digital mobile radio system communications?

A. Regular-Pulse Excited (RPE).
B. Code-Excited Linear Predictive (CLEP).
C. Multi-Pulse Excited (MPE).
D. Linear Excited Code (LEC).

Answer 2

A. Regular-Pulse Excited (RPE).

Question 3

3-83M3: Which of the following codes has gained the widest acceptance for exchange of data from one computer to another?

A. Gray.
B. Baudot.
C. Morse.
D. ASCII.

Answer 3

D. ASCII.

Question 4

3-83M4: The International Organization for Standardization has developed a seven-level reference model for a packet-radio communications structure. What level is responsible for the actual transmission of data and handshaking signals?

A. The physical layer.
B. The transport layer.
C. The communications layer.
D. The synchronization layer.

Answer 4

A The physical layer.

Question 5

3-83M5: What CODEC is used in Phase 2 P25 radios?

A. IWCE
B. IMBC
C. IMMM
D. BMBE

Answer 5

D. BMBE

Question 6

3-83M6: The international Organization for Standardization has developed a seven-level reference model for a packet-radio communications structure. The ___ level arranges the bits into frames and controls data flow.

A. Transport layer.
B. Link layer.
C. Communications layer.
D. Synchronization layer.

Answer 6

B. Link layer.