Communication Systems

Concept: According to the Nyquist Sampling Theorem, the minimum sampling rate required to avoid aliasing must be at least twice the maximum frequency present in the signal.
Step 1: Nyquist rate formula.

Step 2: Substitute given value.

Step 3: Conclusion.
Thus, the Nyquist rate is 10 kHz.

Concept: Noise primarily affects the amplitude of signals in communication systems. Different modulation techniques respond differently to noise.
Step 1: Understanding AM.
In Amplitude Modulation (AM), information is carried by varying the amplitude of the carrier signal.
Step 2: Understanding FM.
In Frequency Modulation (FM), information is carried by varying the frequency, while amplitude remains constant.
Step 3: Effect of noise.

• Noise mainly affects amplitude
• AM signals are easily distorted by noise
• FM signals resist noise since amplitude variations are ignored

Step 4: Conclusion.
Thus, FM is more immune to noise compared to AM.