US 5,465,396 A – In-band on-channel digital broadcasting

1. A method for broadcasting information in a composite signal from a transmitter to one or more receivers, comprising:

• a) frequency modulating an FM message to generate an FM waveform;

  b) multiplying said FM waveform by an AM message to generate a suppressed carrier AM over FM signal;

  c) combining said suppressed carrier AM over FM signal with said FM waveform to generate a large carrier AM over FM composite signal;

  d) transmitting said large carrier AM over FM composite signal;

  e) receiving said large carrier AM over FM composite signal;

  f) recovering one of said FM message and an AM waveform corresponding to said AM message over FM composite signal.