A Complexity-Efficient Sphere Decoder for MIMO Systems

It is well known that although the conventional sphere decoder (SD) achieves optimal maximum likelihood (ML) performance at a reduced complexity compared to the naive ML detector, the SD computational complexity varies with signal noise ratio (SNR) and is high in the low SNR region. This paper proposes a new idea to overcome these drawback that reduces the complexity significantly at a negligible performance loss. The main idea is to scale the...