New Constant Modulus Blind Equalizer with Optimum Tap-length for QAM Signals

Blind equalization algorithms such as Constant Modulus Algorithm (CMA) are used to compensate for signal distortion attributed to inter-symbol interference (ISI) without resorting to training sequence. In QAM signal demodulators, the highest computational load is derived from equalization part. Conventional design of blind equalizers pre-assumes the filter's size, however, this approach could compromise the filter performance or 3 cost. In this paper, a new algorithm named Variable Length CMA (VL-CMA) is proposed using the pseudo Fractional Tap-length (FT) concept to estimate the optimal equalizer's weights and tap-length simultaneously and hence enhancing the equalization process in blind mode with extra efficiency.