A new method of television signal deghosting

A multipath channel in television broadcasting can result in overlaid images (ghosts) or distorted noisy images on the display and is a major problem to be overcome. We propose a method to equalize the multipath distortion for the case of digital transmission and nonminimum phase channels. The method employs noncausal allpass recursive filters operating in reversed time followed by a decision feedback equalizer (DFE). It does not require the computation of zeros of the channel impulse response, and the channel noise level is not enhanced. The equalized impulse response is such that, in most cases, the first nonnegligible sample has the largest magnitude, as appropriate for DFE decoders. Computer simulation results verifying the proposed approach are included.<<ETX>>

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