A low-complexity soft-input/soft-output multiuser detector based on local search algorithms

In this contribution, we consider iterative multiuser detection over coded code-division multiple-access (CDMA) channels from a combinatorial optimization viewpoint and propose a low-complexity soft-input/soft-output (SISO) multiuser detector based on the k-opt local search (LS) algorithm, which was previously used for solving the traveling salesperson problem (TSP). Simulation results and complexity analysis show that the proposed detector can approach closely the performance of the full-complexity a posteriori probability (APP) multiuser detector over highly correlated convolutionally coded channels.