CAJ | 학술논문

针对时变信道下 LDPC 编码的比特交织编码调制（Low Density Parity-Check coded Bit-Interleaved Coded Modulation，LDPC-BICM）系统的因子图模型中信道估计精度低与复杂度较高等问题，改进传统参数消息调度机制，提出一种新的非参数消息调度机制实现联合信道估计与译码。为获得性能与复杂度的折中，一方面从全局角度考虑，合理选择不同的内外迭代组合形式，设计了稀疏估计的消息调度机制，一方面从迭代译码角度考虑，通过选择不同的门限和比较准则，设计了局部选择性更新的消息调度机制。同时，将max-sum规则与MCMC粒子滤波相结合，给出基于硬判决的信道消息更新机制，有效解决了粒子样本枯竭问题，提高了信道估计精度。仿真结果表明，这种消息调度机制不仅有效降低复杂度，并且优于传统的消息调度机制。
침대시변신도하 LDPC 편마적비특교직편마조제（Low Density Parity-Check coded Bit-Interleaved Coded Modulation，LDPC-BICM）계통적인자도모형중신도고계정도저여복잡도교고등문제，개진전통삼수소식조도궤제，제출일충신적비삼수소식조도궤제실현연합신도고계여역마。위획득성능여복잡도적절중，일방면종전국각도고필，합리선택불동적내외질대조합형식，설계료희소고계적소식조도궤제，일방면종질대역마각도고필，통과선택불동적문한화비교준칙，설계료국부선택성경신적소식조도궤제。동시，장max-sum규칙여MCMC입자려파상결합，급출기우경판결적신도소식경신궤제，유효해결료입자양본고갈문제，제고료신도고계정도。방진결과표명，저충소식조도궤제불부유효강저복잡도，병차우우전통적소식조도궤제。
Compared to conventional message schedule in factor graph model of LDPC-BICM(low density parity-check co-ded Bit-Interleaved Coded Modulation)system,a novel nonparametric message update schedule is proposed to get a good trade-off between the performance and complexity.From a global perspective,a message update schedule with sparse channel estimation is designed by selecting different kinds of combination of the outer and inner iteration.And a partial selective mes-sage update schedule is designed from the local iterative decoding perspective by choosing proper comparison rule and thresh-old.In addition,a channel message update schedule is presented to prevent particle impoverishment and improve channel es-timation precision by combining Markov Chain Monte Carlo (MCMC)particle filters (PF)into max-sum rule.Simulation re-sults illustrate effectiveness and performance superiority of the proposed schedule compared to conventional schedule.