Adaptive forgetting factor RLS algorithm equalizer for DS-CDMA system based on adaptive Laguerre lattice filter

A new RLS adaptive algorithm with variable forgetting factor for direct sequence code division multiple access (DS-CDMA) communication system is presented. Intersymbol interference (ISI) arises due to multipath propagation, which destroys the code orthogonality, gives rise to multiple access interference(MAI). Therefore, the objective of this paper is to minimize the effect of ISI with a long impulse response environment based on the proposed receiver. We consider an adaptive Laguerre lattice equalizer which applies an optimal method based on the variable step-size least mean square (VSLMS) algorithm for adaptable forgetting factor RLS algorithm to improve bit error rate (BER) performance of the receiver.