Question

Autocorrelation function of which noise is a constant?

(a) white noise

(b) shot noise

(c) transit time noise

(d) extraterrestrial noise

The question was posed to me in an online quiz.

This interesting question is from Hilbert Transform topic in chapter Double Sideband Suppressed Carrier Modulation of Analog Communications

Answer 1

Right option is (a) white noise

The explanation is: White noise is a random signal having equal intensities at different frequencies. The autocorrelation of white noise signal has a straight vertical line at origin and is zero for rest points. Thus the Autocorrelation function of white noise is constant.