Patent Document ID: 4644562
Application ID: 06770174
Patent Flag: 1

Claim One:
1. Apparatus for combined cross polarization interference cancellation and intersymbol interference equalization of signals received over dispersive terrestrial digital radio transmission channels said signals being in dual polarization mode, said apparatus comprising means for obtaining samples of said signals having cross polarization interference and intersymbol interference, means for equalizing said samples, said means for equalizing being adaptively adjusted by first error signals, said means for equalizing comprising a first transversal filter, said first filter being tapped at selected intervals, means for detecting said equalized samples and for deriving output signals, means for deriving said first error signals by comparing said equalized samples with expected samples of said received signals, and means for canceling said cross polarization interference in said samples by receiving said output signals, said canceler means comprising a second transversal filter which is adaptively adjusted by said first error signals, said second transversal filter being tapped at selected intervals, said canceler means generating second error signals and sending said second error signals to means for subtracting said second error signals from said equalized samples, said equalizer taps being at different intervals from said canceler taps.