Super-exponentially convergent blind fractionally-spaced equalization

The super exponentially convergent method (SEM) of Shalvi and Weinstein (1993) is extended here to adapt a fractionally spaced equalizer (FSE) instead of a symbol-spaced equalizer to recover man-made communication signals distorted by linear time-invariant systems. The extended SEM (ESEM) is applicable to PAM, and AM, PSK, and ASK signals having non-Gaussian symbol sequences received in additive WSS Gaussian noise. It is shown for 64-QAM signals that the ESEM can perform properly when the original SEM cannot do so for examples of the following channels of practical interest: (1) dense multipath channels, and (2) effective channels that arise when bandstop filters are applied to reject partially spectrally overlapping cochannel interference and accordingly reject a portion of the desired signal, too.

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