Question

Which modulation technique is more immune to noise: AM or FM?

• A. AM
• B. FM
• C. Both equally
• D. None

Hint:

FM → More noise resistant (amplitude unaffected); AM → Noise sensitive.

Answer 1

The Correct Option is B

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.