阈值系统中的LDPC译码随机共振及应用研究

发布时间：2018-04-25 04:09

本文选题：随机共振 + 阈上随机共振　；参考：《南京邮电大学学报(自然科学版)》2017年02期

【摘要】：研究阈值阵列系统中低密度奇偶校验码(LDPC)的译码随机共振现象。经过LDPC编码调制的信源序列通过阈值阵列系统添加独立同分布的高斯噪声,接收端采用BP迭代译码算法,译码性能以误码率为测度。仿真结果表明,当信号是阈下时,噪声强度增加,误码率先降后增,随机共振发生,且在阈值单元个数较多时,随机共振现象越明显;当信号是阈上时,噪声总是恶化译码的性能,随机共振不存在。进而研究莱斯噪声作用下的译码随机共振现象,并发现存在阈上随机共振。最后推广到图像在LDPC编译码系统中传输的实际应用中,证实了噪声对其传输效果的明显改善作用。这些结果显示了非线性系统信道译码中噪声的改善作用,扩展了随机共振在信道译码中的应用。
[Abstract]:The decode stochastic resonance of low density parity check codes (LDPCs) in threshold array systems is studied. The source sequence encoded by LDPC is used to add independent and distributed Gao Si noise through the threshold array system. The receiver adopts BP iterative decoding algorithm, and the decoding performance is measured by the bit error rate (BER). The simulation results show that when the signal is subthreshold, the noise intensity increases, the bit error rate decreases first and then increases, the stochastic resonance occurs, and when the number of threshold units is large, the stochastic resonance phenomenon becomes more obvious, and when the signal is on the threshold, The noise always deteriorates the decoding performance, and the stochastic resonance does not exist. Furthermore, the phenomenon of decoded stochastic resonance under Rice noise is studied, and the existence of suprathreshold stochastic resonance is found. Finally, it is extended to the practical application of image transmission in LDPC codec / decode system, and it is proved that the noise can improve the transmission effect obviously. These results show the improvement of noise in channel decoding of nonlinear systems and extend the application of stochastic resonance in channel decoding.
【作者单位】：南京邮电大学理学院;南京邮电大学通信与信息工程学院;
【基金】：国家自然科学基金(61179027) 江苏省“青蓝工程”基金(QL06212006)资助项目
【分类号】：TN911.22

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