Source : WordNet®

frequency modulation
     n : modulation of the frequency of the (radio) carrier wave
         [syn: {FM}]

Source : Free On-Line Dictionary of Computing

Frequency Modulation
     
         (FM) A method of encoding data by varying the
        frequency of a constant amplitude {carrier signal}.
     
        Contrast {Amplitude Modulation}.
     
        (2001-04-02)