Adaptive digital filtering has traditionally been developed based on the minimum mean square error (MMSE) criterion and has found ever-increasing applications in communications. This paper presents an alternative ad...Adaptive digital filtering has traditionally been developed based on the minimum mean square error (MMSE) criterion and has found ever-increasing applications in communications. This paper presents an alternative adaptive filtering design based on the minimum symbol error rate (MSER) criterion for communication applications. It is shown that the MSER filtering is smarter, as it exploits the non-Gaussian distribution of filter output effectively. Consequently, it provides significant performance gain in terms of smaller symbol error over the MMSE approach. Adopting Parzen window or kernel density estimation for a probability density function, a block-data gradient adaptive MSER algorithm is derived. A stochastic gradient adaptive MSER algorithm, referred to as the least symbol error rate, is further developed for sample-by-sample adaptive implementation of the MSER filtering. Two applications, involving single-user channel equalization and beamforming assisted receiver, are included to demonstrate the effectiveness and generality of the proposed adaptive MSER filtering approach.展开更多
在n-Rayleigh信道下,研究了使用选择合并(SC)接收的移动无线传感器网络系统的平均符号误码率(ASEP)和信道容量。基于矩生成函数(MGF)方法,推导了系统采用相干检测的相移键控调制(PSK),正交幅度调制(QAM),脉冲幅度调制(PAM)等数字调制方...在n-Rayleigh信道下,研究了使用选择合并(SC)接收的移动无线传感器网络系统的平均符号误码率(ASEP)和信道容量。基于矩生成函数(MGF)方法,推导了系统采用相干检测的相移键控调制(PSK),正交幅度调制(QAM),脉冲幅度调制(PAM)等数字调制方式的ASEP的精确表达式。同时,也得到了系统信道容量的精确表达式。然后对不同条件下的ASEP和信道容量性能做了数值仿真,理论分析结果与仿真结果相吻合,验证了理论分析结果的正确性。仿真结果表明:随着分集支路数的增加,系统的ASEP和信道容量性能得到了很好的改善,当使用QPSK调制,信噪比为16 d B时,分集支路数L=1,系统的误码率是6×10-2,信道容量是4(bit/s)/Hz;分集支路数L=2,系统的误码率是1×10-2,信道容量是5.1(bit/s)/Hz;分集支路数L=3,系统的误码率是2×10-3,信道容量是5.8(bit/s)/Hz。展开更多
联合战术信息分发系统(Joint Tactical Information Distribution System,JTIDS)是美军C4ISR系统的核心组成部分。它采用RS编码、循环码移键控调制(Cyclic Code-Shift Keying,CCSK)、跳频MSK波形调制等相结合的技术体制。通过对该技术...联合战术信息分发系统(Joint Tactical Information Distribution System,JTIDS)是美军C4ISR系统的核心组成部分。它采用RS编码、循环码移键控调制(Cyclic Code-Shift Keying,CCSK)、跳频MSK波形调制等相结合的技术体制。通过对该技术体制进行研究,分析了JTIDS数据链采用相干解调方式在莱斯衰落信道环境下传输性能,研究并得出了JTIDS系统在莱斯衰落信道下的报文符号错误概率,并应用Matlab仿真工具对JTIDS系统进行了链路级仿真;仿真结果符合JTIDS性能特性,验证了理论分析的正确性。为后续建立JTIDS网络仿真平台,评估JTIDS系统通信网络性能提供了理论依据。展开更多
文摘Adaptive digital filtering has traditionally been developed based on the minimum mean square error (MMSE) criterion and has found ever-increasing applications in communications. This paper presents an alternative adaptive filtering design based on the minimum symbol error rate (MSER) criterion for communication applications. It is shown that the MSER filtering is smarter, as it exploits the non-Gaussian distribution of filter output effectively. Consequently, it provides significant performance gain in terms of smaller symbol error over the MMSE approach. Adopting Parzen window or kernel density estimation for a probability density function, a block-data gradient adaptive MSER algorithm is derived. A stochastic gradient adaptive MSER algorithm, referred to as the least symbol error rate, is further developed for sample-by-sample adaptive implementation of the MSER filtering. Two applications, involving single-user channel equalization and beamforming assisted receiver, are included to demonstrate the effectiveness and generality of the proposed adaptive MSER filtering approach.
文摘在n-Rayleigh信道下,研究了使用选择合并(SC)接收的移动无线传感器网络系统的平均符号误码率(ASEP)和信道容量。基于矩生成函数(MGF)方法,推导了系统采用相干检测的相移键控调制(PSK),正交幅度调制(QAM),脉冲幅度调制(PAM)等数字调制方式的ASEP的精确表达式。同时,也得到了系统信道容量的精确表达式。然后对不同条件下的ASEP和信道容量性能做了数值仿真,理论分析结果与仿真结果相吻合,验证了理论分析结果的正确性。仿真结果表明:随着分集支路数的增加,系统的ASEP和信道容量性能得到了很好的改善,当使用QPSK调制,信噪比为16 d B时,分集支路数L=1,系统的误码率是6×10-2,信道容量是4(bit/s)/Hz;分集支路数L=2,系统的误码率是1×10-2,信道容量是5.1(bit/s)/Hz;分集支路数L=3,系统的误码率是2×10-3,信道容量是5.8(bit/s)/Hz。
文摘联合战术信息分发系统(Joint Tactical Information Distribution System,JTIDS)是美军C4ISR系统的核心组成部分。它采用RS编码、循环码移键控调制(Cyclic Code-Shift Keying,CCSK)、跳频MSK波形调制等相结合的技术体制。通过对该技术体制进行研究,分析了JTIDS数据链采用相干解调方式在莱斯衰落信道环境下传输性能,研究并得出了JTIDS系统在莱斯衰落信道下的报文符号错误概率,并应用Matlab仿真工具对JTIDS系统进行了链路级仿真;仿真结果符合JTIDS性能特性,验证了理论分析的正确性。为后续建立JTIDS网络仿真平台,评估JTIDS系统通信网络性能提供了理论依据。