What aspect of radio equipment does frequency modulation (FM) improve?

Frequency modulation (FM) primarily improves the resistance to noise and fading in radio signal transmission. This enhancement occurs because the information in an FM signal is encoded in variations of frequency rather than amplitude. As a result, FM is less susceptible to the amplitude variations caused by interference and noise in the environment.

In practical terms, this means that during transmission, fluctuations in signal strength, which could be caused by obstacles, atmospheric conditions, or electrical interference, have a minimal impact on the audio quality or signal integrity in FM broadcasts. Listeners experience clearer and more consistent audio, even in challenging conditions.

This increased resistance to noise and fading is one of the reasons FM is widely used for high-fidelity music and communication. Factors such as amplitude control, signal range, and broadcasting time, while relevant to radio communications, do not relate directly to the main benefit that frequency modulation provides over amplitude modulation (AM) in tackling interference and maintaining sound quality.