Patent ID: 6018358
Filing Date: 2000-01-25
Classification: H04H,H04N

Abstract:
A communication circuit comprising at least one source of program material, at least one carrier frequency signal source and at least one first modulator for modulating the at least one carrier frequency signal source with the at least one program material source, the at least one first modulator having a first input terminal, a second input terminal and a first output terminal, and at least one terminal apparatus for demodulating program material-modulated carrier frequency signals, the at least one terminal apparatus including automatic gain control (AGC) means having an AGC bandwidth, at least one first means for coupling the at least one program material source to the at least one first input terminal, at least one second means for coupling the at least one carrier frequency signal source to the at least one second input terminal, and at least one third means for coupling the at least one first output terminal to the at least one terminal apparatus, the at least one first coupling means comprising a second modulator having a third input terminal, a fourth input terminal and a second output terminal, a source of signals having a frequency in the AGC bandwidth, means for coupling the source of signals in the AGC bandwidth to the third input terminal, means for coupling the at least one source of program material to the fourth input terminal, and means for coupling the second output terminal to the first input terminal.