A reduced complexity chip-level SOR-SIC multiuser detector for long-code CDMA systems

In this work a reduced complexity chip-level linear SIC multiuser structure that is asymptotically equivalent to successive over-relaxation (SOR) iteration, which is known to outperform the conventional Gauss-Seidel iteration by an order of magnitude in terms of convergence speed, is proposed. The main advantage of the proposed scheme is its low computational complexity compared to other chip-level and symbol-level SIC schemes equivalent to successive over-relaxation (SOR) iteration. We study the convergence behaviour of the proposed scheme and prove that it converges if the relaxation factor is in the interval. Simulation results are in excellent agreement with theory.