A region-based algorithm for blind equalization of QAM signals

We propose a region-based multimodulus algorithm for blind equalization of high-order quadrature amplitude modulation (QAM) signals. It treats nonconstant modulus constellations as constant modulus ones, converging approximately to the Wiener solution. To avoid divergence, it rejects non-consistent estimates of the transmitted signal. When compared to existing blind multimodulus-type algorithms for equalization of QAM signals, it exhibits considerably lower misadjustment, faster convergence, good tracking capability, without compromising the computational cost. Its good behavior is illustrated through simulation results.