对于原型图低密度奇偶校验(P-LDPC)码的比特交织编码调制系统，P-LDPC码和比特交织器是系统获得良好性能的关键. 针对高阶QAM调制的P-LDPC码编码调制系统，采用修正的EXIT方法分析了不同变量节点度数匹配交织映射方案下系统的收敛门限，从而提出一种基于节点度数匹配的通用交织优化设计准则. 数值分析和仿真结果验证了优化准则的正确性.
As a crucial part in bit-interleavered coded modulation (BICM), protograph low-density paritycheck(P-LDPC) codes and interleavers can greatly improve the performance of a BICM system. In this paper, we use a modified EXIT analysis method to analyze thresholds for a P-LDPC coded BICM system
with high-order QAM in different variable degree matched mapping (VDMM) schemes. A general criterion for optimization of VDMM interleavers is proposed. Results of numerical analysis and simulation show correctness of the optimization criterion.
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