List of top Communication Systems Questions

Given below are two statements, one is labelled as Assertion (A) and the other is labelled as Reason (R):
Assertion (A): The sampling theorem is applicable to continuous time band limited signal.
Reason (R) : The sampling theorem is applicable to stochastic signal. 
In the light of the above statements, choose the correct answer from the options given below.
The power spectral density of a real process X(t) for positive frequencies is shown in figure. Then what is the value of $ R_X (O)$ where $R_X (T)$ is the auto- correlation of X(t)
If X is a Gaussian random variable with mean zero and variance 10, the differential entropy of X is
The biggest advantage of generating an FM signal from the PM signal is
To avoid slope overload distortion in delta modulation for m(t)=10cos(2,000πt) to maintain minimum $(SNR)_Q$ (Signal to Quantization Noise Ratio), the minimum required sampling rate is
The first stage of a two-stage amplifier has a voltage gain of 10, input resistance 600 Ω, equivalent noise resistance 1600 Ω and output resistance 27 KΩ. For a second stage, these values are 25, 81 kΩ and 1 MΩ, respectively. If it is driven by the generator with output impedance 50 Ω, find the noise figure of the amplifier.
The gate used in a DPSK modulator is
What is the minimum number of satellites required from which signals can be recorded to enable a global positioning system receiver to determine latitude, longitude and altitude?
Satellite having the same orbital period as the period of rotation of the earth about its own axis is known as _____
Which of the following is a method of probability sampling ?