Which modulation technique is more resistant to amplitude noise?

Which modulation technique is more resistant to amplitude noise?

• A. Amplitude modulation
• B. Frequency modulation
• C. Both equally
• D. Neither

Answer: (B)

Noise immunity hinges on where the information is carried in the signal. In amplitude modulation, the information sits in the envelope, so any amplitude noise directly alters that envelope and distorts the message, reducing the clarity of the recovered signal. In frequency modulation, the information is contained in the instantaneous frequency rather than the amplitude. receivers typically use a limiter to keep the amplitude nearly constant before demodulation, so amplitude fluctuations from noise don’t much affect the extracted frequency changes. That makes the output more robust to amplitude noise. So frequency modulation is more resistant to amplitude noise.

Noise immunity hinges on where the information is carried in the signal. In amplitude modulation, the information sits in the envelope, so any amplitude noise directly alters that envelope and distorts the message, reducing the clarity of the recovered signal. In frequency modulation, the information is contained in the instantaneous frequency rather than the amplitude. receivers typically use a limiter to keep the amplitude nearly constant before demodulation, so amplitude fluctuations from noise don’t much affect the extracted frequency changes. That makes the output more robust to amplitude noise. So frequency modulation is more resistant to amplitude noise.