In FM to AM conversion, the input of the frequency-modulated signal converted into amplitude modulated signal by

Question

In FM to AM conversion, the input of the frequency-modulated signal converted into amplitude modulated signal by

1. A. Differentiator (Correct answer)
2. B. Integrator
3. C. Comparator
4. D. None of the above

Correct Answer

Option A — Differentiator

Detailed Solution & Explanation

The correct answer is Differentiator.

Key Points

• FM-to-AM conversion is performed by a differentiator.
• Differentiating a frequency-modulated wave produces an output whose amplitude is proportional to the instantaneous frequency of the input, converting frequency variations into amplitude variations.
• The resulting AM signal can then be recovered with a simple envelope detector.

Additional Information

• This is the operating principle of the slope detector and the balanced slope detector, among the earliest FM demodulators.
• An integrator performs the reverse operation and is used in the generation of indirect FM from phase modulation.