A Robust Block - Shanno Adaptive Blind Multiuser Receiver for DS - CDMA Systems
نویسندگان
چکیده
A robust block adaptive blind multiuser receiver based on block-Shanno constant modulus algorithm (BSCMA) with a Quadratic Inequality (QI) constraint on the weight vector norm is developed in this paper. Quadratic constraint has been a widespread methodology to improve the robustness of least-mean square detectors. The BSCMA is realized using a modified Newton’s algorithm without inverse of Hessian matrix estimation. The partition linear interference canceller (PLIC) structure with multiple constraints is invoked to identify the multiple access interference (MAI). The Lagrange multiplier methodology is exploited to solve the QI constraint problem. Simulations are conducted in rich multipath environment under imperfect power control to authenticate the robustness of the proposed detector.
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