Q 71 pg 376 A PCMTDM system multiplexes 24 voiceband channel

(Q 7-1, pg. 376) A PCM-TDM system multiplexes 24 voice-band channels. Each sample is encoded into seven bits, and a framing bit is added to each frame. The sampling rate is 9000 samples per second. BPRZ-AMI encoding is the line format. Determine:

a. Line speed in bits per second.

b. Minimum Nyquist bandwidth.

Solution

Sample rate = 9000 samples per second

No of bits per sample = 7

Therefore Line speed = 9000samples per second * 7 bits per sample = 63000 bits per second

The minimum Nyquist Bandwidth for PCM - TDM id 300 to 3000 Hz. These numbers 24 voice band are standard.