Which type of modulation is more resistant to noise and interference?

Frequency Modulation (FM) is known for its resilience to noise and interference in communication systems. This resilience arises from the way FM encodes information on the carrier wave. In FM, the frequency of the carrier signal varies with the amplitude of the incoming signal, rather than modulating the amplitude itself as in Amplitude Modulation (AM).

Noise tends to affect the amplitude of the signal, making AM more susceptible to fluctuations caused by interference from external sources. In contrast, FM's method of varying frequency means that minor changes in the amplitude caused by noise don’t significantly impact the information being transmitted. The receiver can effectively ignore these amplitude variations, focusing instead on changes in frequency. This inherent characteristic allows FM to maintain a clearer and more reliable signal, even in challenging environments filled with potential interference.

Pulsed Modulation and Phase Modulation also have their specific uses and benefits, but they do not achieve the same level of noise resistance as Frequency Modulation does. Pulsed Modulation deals more with distinct pulses rather than continuous signals, while Phase Modulation varies the phase of the carrier signal. While both can be effective, neither matches FM in terms of noise resistance for continuous wave communications.