Adaptive Minimum BER Reduced-Rank Interference Suppression Algorithms Based on Joint and Iterative Optimization of Parameters

TL;DR

This paper introduces a new adaptive reduced-rank interference suppression method that jointly optimizes filters to minimize BER, with automatic rank selection, demonstrating superior performance in DS-CDMA systems.

Contribution

It presents a novel joint iterative optimization approach for reduced-rank filters based on BER minimization, including adaptive algorithms and automatic rank selection.

Findings

Significantly outperforms existing interference suppression schemes

Effective automatic rank selection based on BER criterion

Improves DS-CDMA system performance

Abstract

In this letter, we propose a novel adaptive reduced-rank strategy based on joint iterative optimization (JIO) of filters according to the minimization of the bit error rate (BER) cost function. The proposed optimization technique adjusts the weights of a subspace projection matrix and a reduced-rank filter jointly. We develop stochastic gradient (SG) algorithms for their adaptive implementation and introduce a novel automatic rank selection method based on the BER criterion. Simulation results for direct-sequence code-division-multiple-access (DS-CDMA) systems show that the proposed adaptive algorithms significantly outperform the existing schemes.