Question

The ratio of ______ the notch filter to the ____ the notch filter gives the Noise Power Ratio.

(a) maximum spectral density inside, spectral density outside

(b) spectral density inside , maximum spectral density outside

(c) spectral density outside, maximum spectral density inside

(d) maximum spectral density outside, spectral density inside

I got this question in an online quiz.

My question is based upon ADC Tradeoffs topic in section Technology Tradeoffs in Software Defined Radio of Cognitive Radio

Answer 1

Correct choice is (c) spectral density outside, maximum spectral density inside

For explanation: The ratio of spectral density outside the notch filter to the maximum spectral density inside the notch filter gives the Noise Power Ratio. Noise Power Ratio is the preferred metric when the number of narrow band channels in the signal spectrum is high. It is measured by flooding the Nyquist bandwidth with white noise.