Blind Channel Equalization in Downlink MC-CDMA Systems Exploiting Guard Interval Redundancy and Excess Codes

This paper introduces a new blind time domain equalization (TEQ) technique for downlink MC-CDMA systems operating in multipath fading channels. This equalization exploits the guard interval redundancy (GI) together with the excess codes (EC). Indeed, since in CDMA-based wireless systems, the number of users per cell is significantly less than the spreading factor, a base station can set apart a subset of the codes, the excess codes that will not be used for spreading. A main advantage of this method is its simplicity compared to subspace based techniques and its relative efficiency illustrated by simulation results