What type of modulation is least affected by noise?

Frequency Modulation (FM) is the type of modulation that is least affected by noise. This is primarily because FM conveys information through variations in the frequency of the carrier wave, rather than its amplitude. Noise typically affects amplitude more significantly than frequency.

In FM, even if there is interference that alters the amplitude of the signal, the receiver can usually still accurately reconstruct the original information as long as the frequency deviation is within a certain range. This capability makes FM particularly robust in environments with high levels of electrical noise, such as radio transmissions and audio broadcasting. As a result, FM is commonly used in applications like music broadcasting where sound quality is crucial.

In contrast, other modulation types, such as Amplitude Modulation (AM), can experience greater distortions in signal quality when interference alters the amplitude, leading to a loss of fidelity in the received signals. Pulse Width Modulation (PWM) and Quadrature Amplitude Modulation (QAM) also face challenges with noise that can affect signal integrity during transmission. Thus, Frequency Modulation stands out for its resilience against noise.