Fractionally spaced blind equalization with low-complexity concurrent constant modulus algorithm and soft decisiondirected scheme

The paper proposes a low-complexity concurrent constant modulus algorithm (CMA) and soft decision-directed (SDD) scheme for fractionally spaced blind equalization of high-order quadrature amplitude modulation channels. We compare our proposed blind equalizer with the recently introduced state-of-art concurrent CMA and decision-directed (DD) scheme. The proposed CMA + SDD blind equalizer is shown to have simpler computational complexity per weight update, faster convergence speed, and slightly improved steady-state equalization performance, compared with the existing CMA + DD blind equalizer. Copyright (c) 2004 John Wiley & Sons, Ltd.