Question

A TDM link has 20 signal channels and each channel is sampled 8000 times/sec. Each sample is represented by seven binary bits and contains an additional bit for synchronization. The total bit rate for the TDM link is

(a) 1180 K bits/sec

(b) 1280 K bits/sec

(c) 1180 M bits/sec

(d) 1280 M bits/sec

This question was addressed to me in unit test.

My question is based upon Digital Transmission topic in division EDC Overview of Electronic Devices & Circuits

Answer 1

Correct answer is (b) 1280 K bits/sec

To explain I would say: Total sample  8000 x 20 = 160 k sample/sec

Bit for each sample  7 + 1 = 8

Bit Rate = 160k x 8 = 1280   kilobits/sec.