A system for broadcasting data (D) that can transmit information in the passband of a broadcast audio-frequency signal (S). The system can determine at least one frequency band (F'.sub.13, . . . , F'.sub.24) and the amplitude (A'.sub.13, . . . , A'.sub.24) of the audio-frequency signal (S). The system...http://www.google.fr/patents/US6151578?utm_source=gb-gplus-shareBrevet US6151578 - System for broadcast of data in an audio signal by substitution of imperceptible audio band with data
System for broadcast of data in an audio signal by substitution of ...
