DEMODULATION OF A SIGNAL TRANSMITTED OVER A FADING CHANNEL USING PHASE ESTIMATION, METHOD AND APPARATUS THEREFOR

摘要

A method and apparatus for estimating the phase differential of a transmitted electromagnetic signal from the amplitude envelope of the signal. The apparatus includes a sampler, phase estimator and demodulator. The phase estimator uses a Hilbert transform. An approximation of the Hilbert transform may also be used to estimate the phase differential with sign ambiguity. The method of determining the sign ambiguity and the approximation of the Hilbert transform may be applied to time domain or frequency domain signals. The phase differential is estimated by taking the differential of a function of the envelope, and applying the Hilbert transform to this differential. The resulting phase differential, after correction for sign ambiguity may be used to demodulate the received signal. Sign ambiguity is resolved by comparing the estimated phase with the ideal phase.