Analog Communication

Amplitude of the carrier varies ✘ Frequency of the carrier remains constant ✘ Phase of the carrier remains constant ✘ All of the above ✔

The baseband signal is not preserved in the envelope of the AM signal ✘ The recovered signal is distorted ✘ It is called over modulation ✘ All of the above ✔

Square law diode modulation ✘ Switching modulation ✘ Frequency discrimination method ✘ Both a and b ✔

Carrier frequency (ωc ) with amplitude A ✘ Upper side band (ωc + ωm) having amplitude mA/2 ✘ Lower side band (ωc – ωm) having amplitude mA/2 ✘ All of the above ✔

Suppresses output audio ✘ Works when there is insufficient desired input signal ✘ Is used to suppress the unwanted channel noise when there is no reception by the receiver ✘ All of the above ✔

Gain of the receiver is adjusted ✘ The gain adjustment depends upon the strength of the received signal ✘ The output provided is a DC voltage ✘ All of the above ✔

Gain of the IF amplifier ✘ Noise figure of the receiver ✘ Gain of RF amplifier ✘ All of the above ✔

Changes with incoming signal frequency ✘ Is poorer at high frequencies ✘ Is the rejection of the adjacent channel at the receiver ✘ All of the above ✔

Better selectivity ✘ Better sensitivity ✘ Improved signal to noise ratio ✘ All of the above ✔

High IF results in poor selectivity ✘ High IF results in problems in tracking of signals ✘ Image frequency rejection becomes poor at low IF ✘ All of the above ✔