Stochastic conjugate gradient based multi-user constant modulus algorithm for use in multiuser DS-CDMA environment

A Stochastic Conjugate Gradient Algorithms (SCGA) is proposed for the solving nonlinear optimization problem assodated with the multi-nser constant modulus algorithm (CC-CMA) for DSCDMA receivers in a multi-user environment. The algorithm referred to as the stochastic conjngate gradient CC-CMA (SCGCC-CMA). Simulatious show that the SCGCCCMA algorithm preserves the fast convergence rate of the block-sbaMo cross correlation wnstmt modulus algorithm (BSCC-CMA) [I], can be configored to perform slmilar to the recursive leist squares (IUS) version of the CC-CMA algorithm, and can outperform the wnventional CC-CMA for less wst. The proposed algoritbna can also he used In DWCDMA systems to solve the problem of joint blind channel eqndization and blind source reparation in a singleuser and multi-user environment. Alternatively, a window sliding parameter may be adjusted to trade off between performance and computation to match system requirements. We will also propose a convergence analysis for the proposed algorithms.