SINGLE AND MULTIPLE SINEWAVE MODULATION AND DEMODULATION TECHNIQUES EMPLOYING CARRIER-ZERO AND CARRIER-PEAK DATA-WORD START AND STOP

摘要

A method for detecting encoded digital data from a substantially sinusoidal waveform, the encoded digital data having one of a first value and a second value at selected phase angles θ_n comprises generating the waveform having an amplitude Y defined by a first function at phase angles lying outside of regions having a range Δθ beginning at each phase angle θ_n, said first function being Y=sin θ; generating the waveform having an amplitude Y defined by the first function at phase angles lying inside the regions having a range of Δθ beginning at each phase angle θ_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 Δθ associated with each phase angle θ_n where data of the second value is to be encoded, the second function being different from Y=sin θ, the detection including deriving sync pulses from minima and maxima of the substantially sinusoidal waveform to frame data words.