IRA code design for MIMO systems with iterative receivers

We consider the design optimization of the irregular repeat accumulate (IRA) codes for multiple-input-multiple-output (MIMO) systems employing iterative receivers. We present the density evolution-based procedure for optimizing IRA code ensemble with the extrinsic information transfer (EXIT) chart matched with that of the soft MIMO demodulator. With a code ensemble mapping relationship between an IRA code and an LDPC code, an optimal IRA code can also be obtained by transforming an optimal LDPC code designed for MIMO systems. Two types of soft MIMO detectors are treated, namely, the MAP detector and the soft interference canceller with linear MMSE filtering (SIC-MMSE).

我们考虑用于采用迭代接收机的多输入多输出（MIMO）系统的不规则重复累积（IRA）码的设计优化。我们提出了基于密度进化的过程，用于优化IRA码系综，使其外信息转移（EXIT）图与软MIMO解调器的EXIT图相匹配。通过IRA码和低密度奇偶校验（LDPC）码之间的码系综映射关系，也可以通过转换为MIMO系统设计的最优LDPC码来获得最优IRA码。我们研究了两种类型的软MIMO检测器，即最大后验概率（MAP）检测器和带有线性最小均方误差（MMSE）滤波的软干扰消除器（SIC - MMSE）。