Abstract
Chi and Chen recently reported a blind equalization algorithm using cumulant based multi-input multi-output inverse filter criteria (MIMO-IFC) for multiuser DS/CDMA systems in multipath. Assuming that the user of interest is the weak user with signal power ε 1 and signal powers of all the interferers are identical, denoted ε, the performance of Chi and Chen's algorithm is superior to that of Tsatsa-his and Xu's blind minimum variance (MV) equalizer for low near-far ratio (NFR) (= ε/ε 1 ≥ 1). In this paper, two blind equalization algorithms, called Algorithms 2 and 3, also using cumulant based MIMO-IFC are proposed. The former (Algorithm 2) can improve the performance of the MV equalizer. The latter (Algorithm 3) based on the former performs as well as Chi and Chen's algorithm for low NFR and outperforms Chi and Chen's algorithm and the MV equalizer for high NFR. Some simulation results are presented to support the efficacy of the proposed algorithms.