A base-band signal can be up-converted using
A. Sine wave
B. Cosine wave
C. Filtering
D. None of the mentioned
The question was asked in a national level competition.
My question is from Signals topic in section Signals and Spectra of Digital Communications
The correct answer is B. Cosine wave
For explanation: A base-band signal can be up-converted to band-pass filter by applying cosine wave.