Question

_______ of a stationary process is actually the variance of the rate of change.

(a) Mean

(b) Mean square

(c) Mean squared derivative

(d) Mean squared integral

The question was asked in examination.

My query is from Multipath Shape Factors for Small topic in division Mobile Radio Propagation: Small – Scale Fading and Multipath of Wireless/Mobile

Answer 1

Correct answer is (c) Mean squared derivative

To elaborate: Mean squared derivative of a stationary process is actually the variance of the rate of change. The mean derivative of the stationary process is zero; the mean squared derivative is the simplest statistics that measures the fading rate of a channel.