UGC NET CSE | December 2015 | Part 2 | Question: 23

Question

Four channels are multiplexed using TDM. If each channel sends 100 bytes/second and we multiplex 1 byte per channel, then the bit rate for the link is

• A. 400 bps
• B. 800 bps
• C. 1600 bps
• D. 3200 bps

Answer 1

Each frame carries 1 byte from each channel; we have 4 channels

The size of each frame, therefore, is 1x4= 4 bytes, or 32 bits.

Each channel is sending 100 bytes/s and a frame carries 1 byte from each channel, the frame rate must be 100 frames per second. The bit rate is 100 × 32 = 3200 bps.

Answer D

Answer 2

one channel  sends 100 bytes/sec

four channel send 400 bytes    multiplex one complete byte per channel

bit rate =400x8=3200bps

hecnce ans is D