COAXIAL CABLE COMMUNICATIONS SYSTEMS AND APPARATUS EMPLOYINGSINGLE AND MULTIPLE SINEWAVE MODULATION AND DEMODULATION TECHNIQUES

摘要

A method for generating a substantially sinusoidal waveform containing encod ed digital data having one of a first value and a second value at selected phas e angles .theta.n comprises generating the waveform having an amplitude Y defined by a first function at phase angles lying outside of regions having a range .DELTA..theta. beginning at each phase angle .theta.n, said first function being Y=sin.theta.; generating the waveform having an amplitude Y defined by the first function at phase angles lying inside the regions havin g a range of .DELTA..theta. beginning at each phase angle .theta.n where data of the first value is to be encoded; and generating the waveform having an amplitude Y defined by a second function at phase angles lying inside the regions having a range of .DELTA..theta. associated with each phase angle .theta.n where data of the second value is to be encoded, the second functio n being different from Y=sin.theta..