Question

White noise with power density No/2 = 6 microW/Hz is applied to an ideal filter of gain 1 and bandwidth W rad/s. If the output’s average noise power is 15 watts, the bandwidth W is

(a) 2.5 x 10 ^ (-6)

(b) 2.5p x 10  ^  (-6)

(c) 5 x 10  ^  (-6)

(d) p5 x 10  ^  (-6)

I have been asked this question in quiz.

I want to ask this question from Random Process in chapter EDC Overview of Electronic Devices & Circuits

Answer 1

Right choice is (b) 2.5p x 10  ^  (-6)

The best I can explain: Pyy = 1/2p Integral(?xx(w) |H(w)|^2 dw ) from plus infinity to minus infinity. Hence solve for W.