Question

The ______ of out-of-band signal with bandpass characteristic of the receiver gives the interference in the receiver owing to out-of-band energy at the transmitter.

(a) correlation

(b) correlation and convolution

(c) integral

(d) convolution

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This interesting question is from RF and IF Processing Tradeoffs topic in division Technology Tradeoffs in Software Defined Radio of Cognitive Radio

Answer 1

Correct answer is (d) convolution

The best explanation: The convolution of out-of-band signal with bandpass characteristic of the receiver gives the interference in the receiver owing to out-of-band energy at the transmitter.This type of interference can affect the roll-offs. Frequency separation is employed to suppress this type of interference.