基于低密度校驗碼編碼的MIMO系統(tǒng)方案
LDPC Coded MIMO System Scheme
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摘要: 該文采用數(shù)值仿真的方法探討了MIMO系統(tǒng)中采用低密度校驗(LDPC)碼作為信道編碼后的系統(tǒng)性能,針對LDPC碼的置信度傳播譯碼算法,提出了基于因子圖(Factor graph)的聯(lián)合迭代檢測譯碼最大后驗概率(MAP)算法,分析比較了發(fā)射端分別采用獨立編碼和聯(lián)合編碼對系統(tǒng)性能的影響,仿真結(jié)果表明,LDPC碼可以充分利用MIMO系統(tǒng)中空間分集和時間分集性能提高系統(tǒng)的有效分集增益,并且聯(lián)合迭代檢測譯碼算法對這兩種發(fā)射端編碼結(jié)構(gòu)的系統(tǒng)性能增益有較大差別。
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關(guān)鍵詞:
- 低密度校驗碼; MIMO系統(tǒng); 因子圖
Abstract: In this paper, the performance of the LDPC coded MIMO system scheme is evaluated through numerical simulations, and according to the belief propagation decoding algorithm of LDPC codes, a combined iterative detection/decoding MAP algorithm based on the factor-graph representation is proposed. The system performance is analyzed under two transmitter encoding structures, namely the separate encoding structure and the combined encoding structure respectively. Simulation results show that LDPC codes can increase the effective diversity gain by utilizing both the space and the time diversity effects of the MIMO system, and the combined iterative detection/decoding algorithm results in different performance gain for the two transmitter encoding structures. -
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