Question

Examples of continuous wave analog modulation is
(A) AM
(B) PAM
(C) SAM
(D) None of the above

Answer 1

Hint: We need to identify the different types of modulation in the signal. Continuous analogue modulations are modulations which are applied continuously on the input signal.

Complete answer:
In general, analogue modulation is a kind of modulation technique where the modulation is continuously applied to the input analogue signal. A few examples of analogue modulation include Amplitude modulation, and angle modulation. Angle modulation is majorly divided into frequency modulation and phase modulation.
Amplitude modulation – this is the kind of modulation done by varying the amplitude of the carrier wave (input signal) with the amplitude of the modulating wave.
Frequency – this is a kind of modulation performed by the variation of the frequency of the input signal (carrier signal) usually in accordance to a modulating signal.
Phase modulation - this is the variation of the phase of the wave of the input signal (carrier signal) in accordance to the modulating signal.
Another technique of modulation is the pulse modulation technique – in this technique the modulation is not continuously applied on the input signal, but rather applied at intervals.
Examples of these types of modulation includes pulse amplitude modulation (PAM), the pulse duration modulation, the pulse position modulation (PPM) and pulse width modulation (PWM).
Hence, from these we can conclude that the amplitude modulation (AM) is the continuous wave analogue modulation.
So the correct option is A.

Note:
A popular application of modulation is to carry audio signals uniquely to the receiver end without interference from other signals. The FM and AM radio stations use modulation techniques. For example, the frequency tuned in when listening to an FM radio station is actually the frequency of their modulation signal, which allows their audio signal to be carried uniquely without interference from other radio stations.