24 telephone channels, each band limited to 3.4 kHz, are to be time division multiplexed by using PCM, calculate the bandwidth of PCM system for 128 quantization levels and an 8 KHz sampling frequency

Electronics and Communication Engineering (ECE) : Communication Systems - Quiz(MCQ)

1.299 MHz

1.54 MHz

2 MHz

192 kHz

Correct Answer : Option (B) : 1.54 MHz

Explanation :

Given, n = 24, f_m = 3.4 kHz

M = 128,

2^N = 128 => n = 7

But f_s = 2f_m, here we will consider f_s (sampling) frequency

instead at 2f_m => 2 x 3.4 kHz => 6.8 KHz.

B.W. = [24(7 + 1)] 8 kHz = 1.54 MHz.

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