Principles of Communication Engineering

What is the purpose of pre-emphasis in FM transmission?
(i) Reduce low-frequency noise components
(ii) Improve signal-to-noise ratio
(iii) Suppress higher-frequency
(iv) Increase bandwidth

If a noise signal has a mean of 0 and a standard deviation of 1, what is its variance?
(i) 0
(ii) 1
(iii) 2
(iv) 4

The power spectral density of white noise is
(i) Zero
(ii) Constant
(iii) Exponential
(iv) Parabolic

Discuss the impact of white noise in amplitude modulation systems and derive the signal-to-noise ratio (SNR).

Explain the concept of probability density function (PDF) and cumulative distribution function (CDF) in random processes.

Explain the basics of probability and random processes used in communication systems.

What are pre-emphasis and de-emphasis networks? Explain their need in communication systems.