为提高水声通信系统的数据传输速率和可靠性,提出一种新的基于软信道估计的联合迭代均衡译码(joint iterative equalization and decoding,JIED)水声通信方法。该方法利用软输入软输出(soft in soft out,SISO)译码器反馈的外似然比计算...为提高水声通信系统的数据传输速率和可靠性,提出一种新的基于软信道估计的联合迭代均衡译码(joint iterative equalization and decoding,JIED)水声通信方法。该方法利用软输入软输出(soft in soft out,SISO)译码器反馈的外似然比计算符号软估计信息,并应用于稀疏自适应信道估计器的抽头系数更新过程。经过译码器和均衡器之间多次迭代交换软信息联合处理接收信号,信道估计精度与均衡效果显著提高。水声通信实验结果表明在通信距离1.8km、2kHz有效带宽内,新方法在第2次迭代后即可实现2kb/s的无误码传输,可以有效提高系统可靠性和传输速率。展开更多
针对BCH-LDPC级联编码的MIMO系统,提出一种外码译码反馈联合迭代检测译码算法。该算法在迭代检测译码结构的基础上,引入外码硬判决译码反馈。MIMO检测器利用反馈的硬判决信息,经过映射处理后用于更新检测器的检测列表,以减小迭代检测译...针对BCH-LDPC级联编码的MIMO系统,提出一种外码译码反馈联合迭代检测译码算法。该算法在迭代检测译码结构的基础上,引入外码硬判决译码反馈。MIMO检测器利用反馈的硬判决信息,经过映射处理后用于更新检测器的检测列表,以减小迭代检测译码算法的运算量。同时,利用外码译码结果直接计算部分LDPC码译码初始信息,提高软信息的可靠性,从而提高系统性能。仿真结果表明,与迭代检测译码算法相比,所提算法能够使处理一帧数据时的平均检测次数减少57.1%,从而降低算法运算量。同时由于外码译码反馈的引入,所提算法至少能够获得0.2 d B性能增益。展开更多
This paper describes a coded cooperative multiple-input multiple-output(MIMO) scheme,where structured low-density parity-check(LDPC) codes belonging to a family of repeat-accumulate(RA) codes are employed.The outage p...This paper describes a coded cooperative multiple-input multiple-output(MIMO) scheme,where structured low-density parity-check(LDPC) codes belonging to a family of repeat-accumulate(RA) codes are employed.The outage probability of the scheme over Rayleigh fading channels is deduced.In an unknown channel state information(CSI) scenario,adaptive transversal filters based on a spatio-temporal recursive least squares(ST-RLS) algorithm are adopted in the destination to realize receive diversity gain.Also,a joint 'Min-Sum' iterative decoding is effectively carried out in the destination.Such a decoding algorithm agrees with the bilayer Tanner graph that can be used to fully characterize two distinct structured LDPC codes employed by the source and relay.Simulation results verify the effectiveness of the adopted filter in the coded cooperative MIMO scheme.Theoretical analysis and numerical simulations show that the LDPC coded cooperative MIMO scheme can well combine cooperation diversity,multi-receive diversity,and channel coding gains,and clearly outperforms coded noncooperation schemes under the same conditions.展开更多
文摘为提高水声通信系统的数据传输速率和可靠性,提出一种新的基于软信道估计的联合迭代均衡译码(joint iterative equalization and decoding,JIED)水声通信方法。该方法利用软输入软输出(soft in soft out,SISO)译码器反馈的外似然比计算符号软估计信息,并应用于稀疏自适应信道估计器的抽头系数更新过程。经过译码器和均衡器之间多次迭代交换软信息联合处理接收信号,信道估计精度与均衡效果显著提高。水声通信实验结果表明在通信距离1.8km、2kHz有效带宽内,新方法在第2次迭代后即可实现2kb/s的无误码传输,可以有效提高系统可靠性和传输速率。
文摘针对BCH-LDPC级联编码的MIMO系统,提出一种外码译码反馈联合迭代检测译码算法。该算法在迭代检测译码结构的基础上,引入外码硬判决译码反馈。MIMO检测器利用反馈的硬判决信息,经过映射处理后用于更新检测器的检测列表,以减小迭代检测译码算法的运算量。同时,利用外码译码结果直接计算部分LDPC码译码初始信息,提高软信息的可靠性,从而提高系统性能。仿真结果表明,与迭代检测译码算法相比,所提算法能够使处理一帧数据时的平均检测次数减少57.1%,从而降低算法运算量。同时由于外码译码反馈的引入,所提算法至少能够获得0.2 d B性能增益。
基金Project (No. 20105552) supported by the Science and Technology on Avionics Integration LaboratoryNational Aeronautical Science Foundation of China
文摘This paper describes a coded cooperative multiple-input multiple-output(MIMO) scheme,where structured low-density parity-check(LDPC) codes belonging to a family of repeat-accumulate(RA) codes are employed.The outage probability of the scheme over Rayleigh fading channels is deduced.In an unknown channel state information(CSI) scenario,adaptive transversal filters based on a spatio-temporal recursive least squares(ST-RLS) algorithm are adopted in the destination to realize receive diversity gain.Also,a joint 'Min-Sum' iterative decoding is effectively carried out in the destination.Such a decoding algorithm agrees with the bilayer Tanner graph that can be used to fully characterize two distinct structured LDPC codes employed by the source and relay.Simulation results verify the effectiveness of the adopted filter in the coded cooperative MIMO scheme.Theoretical analysis and numerical simulations show that the LDPC coded cooperative MIMO scheme can well combine cooperation diversity,multi-receive diversity,and channel coding gains,and clearly outperforms coded noncooperation schemes under the same conditions.