Optimization of mapping rule of bit-interleaved Turbo coded modulation with 16 quadrature amplitude modulation (QAM) is investigated based on different impacts of various encoded bits sequence on Turbo decoding perfor...Optimization of mapping rule of bit-interleaved Turbo coded modulation with 16 quadrature amplitude modulation (QAM) is investigated based on different impacts of various encoded bits sequence on Turbo decoding performance. Furthermore, bit-interleaved in-phase and quadrature phase (I-Q) Turbo coded modulation scheme are designed similarly with I-Q trellis coded modulation (TCM). Through performance evaluation and analysis, it can be seen that the novel mapping rule outperforms traditional one and the I-Q Turbo coded modulation can not achieve good performance as expected. Therefore, there is not obvious advantage in using I-Q method in bit-interleaved Turbo coded modulation.展开更多
Iterative demodulation and decoding scheme is analyzed and modulation labeling is considered to be one of the crucial factors to this scheme. By analyzing the existent mapping design criterion, four aspects are found ...Iterative demodulation and decoding scheme is analyzed and modulation labeling is considered to be one of the crucial factors to this scheme. By analyzing the existent mapping design criterion, four aspects are found as the key techniques for choosing a label mapping. Based on this discovery, a novel mapping design criteflon is proposed and two label mappings are searched according to it. Simulation results show that the performance of BICM-ID using the novel mappings is better than the former ones. The extrinsic information transfer （EXIT） chart is introduced and it is used to evaluate the proposed mapping design criteria.展开更多
介绍了协同分集技术与放大前传(Amplify and Forward,AF)和解码前传(Decode and Forward,DF)两种中继模式,把两用户协同推广至多用户协同,并通过仿真比较了PSK(Phase Shifting Keying)与QAM(Quadrature Amplitude Modulation)两种调制...介绍了协同分集技术与放大前传(Amplify and Forward,AF)和解码前传(Decode and Forward,DF)两种中继模式,把两用户协同推广至多用户协同,并通过仿真比较了PSK(Phase Shifting Keying)与QAM(Quadrature Amplitude Modulation)两种调制下的性能.结果表明:性能随着协同用户数的增加而提高;且QAM调制下系统性能优于PSK调制.展开更多
基于Vi t erbi-Vi t erbi算法原理,提出了一种适用于Square m-QAM相干光通信系统载波相位估计的改进算法,能够充分利用所有符号的相位信息进行载波相位估计。仿真分析表明,改进算法比现有其它算法复杂度更低,相位噪声容限更大,当BER=10-...基于Vi t erbi-Vi t erbi算法原理,提出了一种适用于Square m-QAM相干光通信系统载波相位估计的改进算法,能够充分利用所有符号的相位信息进行载波相位估计。仿真分析表明,改进算法比现有其它算法复杂度更低,相位噪声容限更大,当BER=10-3、SNR代价为2dB时,16-QAM和64-QAM允许的激光线宽分别为1.1MHz和0.25MHz。展开更多
Mapping design criteria of bit-interleaved coded modulation with iterative decoding (BICM-ID) with square 16QAM are analyzed. Three of the existing criteria are analyzed and compared with each other. Through the compa...Mapping design criteria of bit-interleaved coded modulation with iterative decoding (BICM-ID) with square 16QAM are analyzed. Three of the existing criteria are analyzed and compared with each other. Through the comparison, two main characters of the mapping design criteria are found. They are the harmonic mean of the minimum squared Euclidean distance and the average of Hamming distances with the nearest Euclidean distance. Based on these two characters, a novel mapping design criterion is proposed and a label mapping named mixed mapping is searched according to it. Simulation results show that mixed mapping performs better than the other mappings in BICM-ID system.展开更多
文摘Optimization of mapping rule of bit-interleaved Turbo coded modulation with 16 quadrature amplitude modulation (QAM) is investigated based on different impacts of various encoded bits sequence on Turbo decoding performance. Furthermore, bit-interleaved in-phase and quadrature phase (I-Q) Turbo coded modulation scheme are designed similarly with I-Q trellis coded modulation (TCM). Through performance evaluation and analysis, it can be seen that the novel mapping rule outperforms traditional one and the I-Q Turbo coded modulation can not achieve good performance as expected. Therefore, there is not obvious advantage in using I-Q method in bit-interleaved Turbo coded modulation.
文摘Iterative demodulation and decoding scheme is analyzed and modulation labeling is considered to be one of the crucial factors to this scheme. By analyzing the existent mapping design criterion, four aspects are found as the key techniques for choosing a label mapping. Based on this discovery, a novel mapping design criteflon is proposed and two label mappings are searched according to it. Simulation results show that the performance of BICM-ID using the novel mappings is better than the former ones. The extrinsic information transfer （EXIT） chart is introduced and it is used to evaluate the proposed mapping design criteria.
文摘介绍了协同分集技术与放大前传(Amplify and Forward,AF)和解码前传(Decode and Forward,DF)两种中继模式,把两用户协同推广至多用户协同,并通过仿真比较了PSK(Phase Shifting Keying)与QAM(Quadrature Amplitude Modulation)两种调制下的性能.结果表明:性能随着协同用户数的增加而提高;且QAM调制下系统性能优于PSK调制.
文摘基于Vi t erbi-Vi t erbi算法原理,提出了一种适用于Square m-QAM相干光通信系统载波相位估计的改进算法,能够充分利用所有符号的相位信息进行载波相位估计。仿真分析表明,改进算法比现有其它算法复杂度更低,相位噪声容限更大,当BER=10-3、SNR代价为2dB时,16-QAM和64-QAM允许的激光线宽分别为1.1MHz和0.25MHz。
文摘Mapping design criteria of bit-interleaved coded modulation with iterative decoding (BICM-ID) with square 16QAM are analyzed. Three of the existing criteria are analyzed and compared with each other. Through the comparison, two main characters of the mapping design criteria are found. They are the harmonic mean of the minimum squared Euclidean distance and the average of Hamming distances with the nearest Euclidean distance. Based on these two characters, a novel mapping design criterion is proposed and a label mapping named mixed mapping is searched according to it. Simulation results show that mixed mapping performs better than the other mappings in BICM-ID system.
