Question

In amplitude modulation, which of the following varies?

(a) Frequency of the carrier

(b) Frequency of the information signal

(c) Amplitude of the carrier wave

(d) Amplitude of the information signal

The question was posed to me during a job interview.

I need to ask this question from Modulation and Multiplexing topic in division Introduction to Electronic Communication of Avionics

Answer 1

Correct option is (c) Amplitude of the carrier wave

Easiest explanation: In amplitude modulation, the amplitude of the carrier wave is modulated with respect to the information signal. The frequency and the phase of both the carrier and the information signal remain constant.