in full frequency modulation
Variation of the frequency of a carrier wave (commonly a radio wave ) in accordance with variations in the audio signal being sent.
Developed by American electrical engineer AM . Such noise generally affects the amplitude of a radio wave but not its frequency, so an FM signal remains virtually unchanged. FM is also better able to transmit sounds in stereo than AM. Commercial FM broadcasting stations transmit their signals in the frequency range of 88 megahertz (MHz) to 108 MHz.