Question

If the spectrum of a narrow band noise is symmetrical and it has a power density spectrum 4×10-6. Power density of quadrature component is ________

(a) 2 x 10^-6

(b) 5 x 10^-6

(c) 3 x 10^-6

(d) 4 x 10^-6

I got this question in homework.

The above asked question is from Modulation Using Non-Linear Devices (Balanced Modulator) topic in section Amplitude Modulation of Analog Communications

Answer 1

Correct option is (a) 2 x 10^-6

For explanation: Power density is the amount of power per unit volume. Quadrature component is a amplitude modulated sinusoid which is offset in phase by one quarter cycle.

Power density of quadrature component is