Application of conjugate gradient methods in MMSE equalization for the forward link of DS-CDMA

The chip-level MMSE estimate of the (multiuser) synchronous sum signal transmitted by the base-station, followed by a correlate and sum, has been shown to perform very well in the CDMA forward link using orthogonal channel codes. In this paper, adaptive chip-level MMSE estimation based on the conjugate gradient (CG) algorithm is presented. Our simulations show that, adaptive CG using the pilot channel for training can achieve excellent convergence at a moderate computational cost.

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