Patent ID: 6418300
Filing Date: 2002-07-09
Classification: H04H

Abstract:
A process of transmitting mixed analog and digital signals by one and the same transmitter and intended to be received either by amplitude-modulation receivers or single-sideband receivers and digital type receivers adapted for the demodulation of multi-subcarriers, said process comprising:transmitting a composite signal whose frequency spectrum includes a first analog spectrum representative of an amplitude modulation or of a single sideband and of a second spectrum including the multi-subcarriers; and regulating a residual-carrier level of the mixed signal, wherein the first and second spectra occupy two disjoint frequency bands, wherein the spectrum of the analog signal is one of an amplitude-modulated signal, a single-sideband-modulated signal, and a VSB modulated signal, and wherein the spectrum of the digital signal includes a specified number of regularly spaced subcarriers which are modulated independently of one another according to a multiple phase state modulation process.