A new approach for iterative decoding on MIMO channels via sphere decoding

A soft iterative detection and decoding (IDD) scheme based on the sphere decoding technique for coded multiple-input multiple-output spatial multiplexing (MIMO-SM) systems is considered in this paper. We propose a new approach to approximate the maximum a-posteriori (MAP) cost function by a quadratic function such that the MAP search can be carried out by list sphere decoding (LSD). Performance of the coded MIMO-SM system with this approach is evaluated by simulation. It is shown that the proposed approach can achieve performance comparable to an existing approach.