Two analog signals x 1 (t) and x 2 (t) are to be transmitted over
| Two analog signals x1(t) and x2(t) are to be transmitted over a channel by means of time division multiplexing (TDM). The highest frequency of x1(t) = 4 kHz and that of x2(t) is 4.5 kHz. The minimum value of the sampling rate is:
A. 8 kHz
B. <p>9 kHz</p>
C. 4.5 kHz
D. 4 kHz
Please scroll down to see the correct answer and solution guide.
Right Answer is: B
SOLUTION
Concept:
Two signals when time division multiplexed must be sampled at a Nyquist frequency of the highest frequency signal.
i.e. if x1(t) is limited to fm1 and x2(t) is limited to fm2,
such that fm2 > fm1
then fm2 will decide the Nyquist rate.
Calculation:
Given, Highest frequency of x1(t) = 4 kHz
And highest frequency of x2(t) = 4.5 kHz
So, the minimum sampling frequency is decided by x2(t)
(Sampling Frequency) fs= 2.fm2
= 2 × 4.5 k
= 9 kHz