Time scaling operation is also known as:
A. Down-sampling
B. Up-sampling
C. Sampling
D. None of the mentioned
Answer:A
Time scaling operation is also known as:
A. Down-sampling B. Up-sampling C. Sampling D. None of the mentioned
Explanation: If the signal x(n) was originally obtained by sampling a signal xa(t), then x(n)=xa(nT). Now, y(n)=x(2n)(say)=xa(2nT). Hence the time scaling operation is equivalent to changing the sampling rate from 1/T to 1/2T, that is to decrease the rate by a factor of 2. So, time scaling is also called as down-sampling.