Question

The spectral density of white noise is ____________

(a) Exponential

(b) Uniform

(c) Poisson

(d) Gaussian

I got this question during an interview.

Enquiry is from Properties of ROC in section Laplace Transform and System Design of Signals and Systems

Answer 1

Correct option is (b) Uniform

To elaborate: The distribution of White noise is homogeneous over all frequencies. Power spectrum is the Fourier transform of the autocorrelation function. Therefore, the power spectral density of white noise is uniform.