A Stable Expected Complexity Sphere Detection with IRA Enhancement

A new detection method based on sphere decoding (SD) is proposed in this paper to approach near-maximum likelihood (ML) performance for multi-input multi- output (MIMO) detection. The feature of the proposed method is that the complexity which means the electric power consumption in detection processing is stable for a wide range of signal-to-noise ratios (SNRs) and a number of antennas. We hold the complexity by a tree pruning mechanism which obtains detection radius through the close-form expression for the SD expected complexity R.Gowaikar and B.Hassibi, 2007. And the Increasing Radii Algorithm (IRA) mechanism is used in the method to reduce the SER at the stable expected complexity. The simulation results show that the method gets a low stable expected complexity without sacrificing much in terms of performance.