Question

Received signal can be expressed as ______ of transmitted signal with channel impulse response.

(a) Addition

(b) Subtraction

(c) Division

(d) Convolution

I have been asked this question in examination.

This intriguing question originated from Impulse Response Model of a Multipath Channel topic in section Mobile Radio Propagation: Small – Scale Fading and Multipath of Wireless/Mobile

Answer 1

Correct option is (d) Convolution

To elaborate: The received signal y(t) can be expressed as a convolution of transmitted signal x(t) with impulse response of mobile radio channel. The variable t represents the time variations due to motion and the channel impulse multipath delay for fixed value of t.