The 16-ary quadrature amplitude modulation （16QAM） is a high spectral efficient scheme for high-speed transmission systems. To remove the phase ambiguity in the coherent detection system, differential-encoded 16QAM ...The 16-ary quadrature amplitude modulation （16QAM） is a high spectral efficient scheme for high-speed transmission systems. To remove the phase ambiguity in the coherent detection system, differential-encoded 16QAM （DE-16QAM） is usually used, however, it will cause performance degradation about 3 dB as compared to the conventional 16QAM. To overcome the performance loss, a serial concatenated system with outer low density parity check （LDPC） codes and inner DE-16QAM is proposed. At the receiver, joint iterative differential demodulation and decoding （ID） is carried out to approach the maximum likelihood performance. Moreover, a genetic evolution algorithm based on the extrinsic information transfer chart is proposed to optimize the degree distribution of the outer LDPC codes. Both theoretical analyses and simulation results indicate that this algorithm not only compensates the performance loss, but also obtains a significant performance gain, which is up to 1 dB as compared to the conventional non-DE-16QAM.展开更多
将二维映射下的软输入软输出解映射MAX-LOG-MAP算法扩展到多维映射比特交织编码调制及迭代译码(BICM-ID)系统,并首次结合多天线系统下的列表球形译码,提出一种简化MD-LSD(multi-dimensional list sphere decoding)算法。新算法大幅降低...将二维映射下的软输入软输出解映射MAX-LOG-MAP算法扩展到多维映射比特交织编码调制及迭代译码(BICM-ID)系统,并首次结合多天线系统下的列表球形译码,提出一种简化MD-LSD(multi-dimensional list sphere decoding)算法。新算法大幅降低了多维解映射的计算复杂度。仿真结果表明,列表长度满足一定范围时,采用简化MD-LSD算法解映射算法的性能损失可以忽略。展开更多
基金supported by the National Natural Science Foundation of China(61171101)the State Major Science and Technology Special Projects(2009ZX03003-011-03)
文摘The 16-ary quadrature amplitude modulation （16QAM） is a high spectral efficient scheme for high-speed transmission systems. To remove the phase ambiguity in the coherent detection system, differential-encoded 16QAM （DE-16QAM） is usually used, however, it will cause performance degradation about 3 dB as compared to the conventional 16QAM. To overcome the performance loss, a serial concatenated system with outer low density parity check （LDPC） codes and inner DE-16QAM is proposed. At the receiver, joint iterative differential demodulation and decoding （ID） is carried out to approach the maximum likelihood performance. Moreover, a genetic evolution algorithm based on the extrinsic information transfer chart is proposed to optimize the degree distribution of the outer LDPC codes. Both theoretical analyses and simulation results indicate that this algorithm not only compensates the performance loss, but also obtains a significant performance gain, which is up to 1 dB as compared to the conventional non-DE-16QAM.
文摘将二维映射下的软输入软输出解映射MAX-LOG-MAP算法扩展到多维映射比特交织编码调制及迭代译码(BICM-ID)系统,并首次结合多天线系统下的列表球形译码,提出一种简化MD-LSD(multi-dimensional list sphere decoding)算法。新算法大幅降低了多维解映射的计算复杂度。仿真结果表明,列表长度满足一定范围时,采用简化MD-LSD算法解映射算法的性能损失可以忽略。
