Dual‐mode multi‐modulus algorithms for blind equalisation of QAM signals

Abstract

SUMMARYA dual-mode multi-modulus algorithm (DM-MMA) and a stop-and-go dual-mode multi-modulus algorithm (SAG-DMMMA) for blind equalisation of high-order quadrature amplitude modulation (QAM) signals are proposed. Simulation results show the proposed blind equalisation algorithms have faster convergence speed and smaller steady-state mean square error, compared with the recently introduced multi-modulus algorithm.

Min‐norm based alphabet‐matching algorithm for adaptive blind equalisation of high‐order QAM signals

“…To overcome the problems caused by switching in dual mode , a hybrid strategy was proposed in that involves minimising the MM cost function J MM penalised by J Gauss , thus leading to the cost function where parameter β tunes the weights of J MM ( w ) and J Gauss ( w ) in J Gauss‐MM ( w ). The resulting algorithm will be referred to as Gauss‐MMA.…”

“…To overcome the problems caused by switching in dual mode [6,7], a hybrid strategy was proposed in [8] that involves minimising the MM cost function J MM penalised by J Gauss , thus leading to the cost function [8]…”

“…More recently, the family of alphabet‐matching (AM) function‐based algorithms has been proposed and proven to outperform the MMA. The AM function is used either in a dual mode with conventional algorithms like CMA and MMA or as a penalty term added to the cost function of one of these conventional algorithms .…”