A successive interference cancellation algorithm in MIMO systems via breadth-first search

A successive interference cancellation (SIC) algorithm based on breadth-first search (BFS) is developed to achieve a soft-input soft-output detector via the tree structure of the MIMO system model in this paper. Instead of visiting all nodes of the tree, the proposed BFS-SIC algorithm only browses and extends those paths with large metrics. If paths are enough, the performance of BFS-SIC algorithm can approach that of sphere decoding but is much more flexible due to its providing a good tradeoff between complexity and performance. Moreover, the BFS-SIC algorithm possesses path metrics including only scalar operations rather than matrix operations. Simulation results demonstrate the effectiveness of the proposed algorithm.