利用微波在对流层的散射现象进行电磁侦测是实现超视距雷达辐射源探测的有效手段之一.随着探测威力、分辨力要求的提高,对于散射多径引起的衰落相关导致接收协方差矩阵秩亏损,令多重信号分类(multiple signal classification,MUSIC)等...利用微波在对流层的散射现象进行电磁侦测是实现超视距雷达辐射源探测的有效手段之一.随着探测威力、分辨力要求的提高,对于散射多径引起的衰落相关导致接收协方差矩阵秩亏损,令多重信号分类(multiple signal classification,MUSIC)等基于特征分解的超分辨类测向算法失效,以及散射机制下大型分布式源产生的相位扩散导致接收阵列流形失配等问题,文章根据近期建立的散射衰落相关模型设计相互独立的多波束排布,并相应地提出一种修正的线性约束最小方差(linearly constrained minimum variance,LCMV)方法补偿相位扩散影响,将接收信号由受衰落相关影响的阵元域变换到独立的波束域,并在波束域进行超分辨测向.仿真结果验证了测向算法在散射多径衰落条件下的有效性,对600km目标散射信号积累300快拍能达到0.5°的估角精度.展开更多
An ultra-wideband impulse radar was studied for the detection of buried life in coal mines. An improved Empirical Mode Decomposition (EMD) method based on a cross-correlation filter was proposed for reduction of multi...An ultra-wideband impulse radar was studied for the detection of buried life in coal mines. An improved Empirical Mode Decomposition (EMD) method based on a cross-correlation filter was proposed for reduction of multipath and noise interference. Multipath interference was first removed by cross-corre- lation filtering. Then the delays of each pulse in every echo were summed. An EMD algorithm was used for noise reduction for the total delay of each echo. The corresponding EMD results of every echo were then summed and averaged. Finally, evidence for the existence of buried life and their position were obtained from amplitude-frequency curves of the averaged EMD results. Detailed simulation experi- ments are presented to validate the effectiveness of this proposed method. The experimental results show that this method can efficiently eliminate multipath interference and reduce noise interference in echoes, which makes detection and location of buried life in coal mines more accurate.展开更多
Y99-61517-433 9915280接收机算法和性能分析(含7篇文章)=Session 13:re-ceiver algorithms and performance analysis[会,英]//1998 IEEE International Conference on Communica-tions,Vol.1 of 3.—433～469(MaG)本组7篇文章。讨论...Y99-61517-433 9915280接收机算法和性能分析(含7篇文章)=Session 13:re-ceiver algorithms and performance analysis[会,英]//1998 IEEE International Conference on Communica-tions,Vol.1 of 3.—433～469(MaG)本组7篇文章。讨论了在线性时间选择性瑞利衰落信道上传输的相移键控信号的差分检测,M 元相移键控的非相干序列检测的性能分析,利用有非相干前端的接收机的预编码信号的检测,受时间相关多径现象损害的数字无线链路的截止速率,对于时变信道的强顽健自适应信号传送,一般衰落信道上线性调制信号差错率计算的一种统一方法,联合信道和数据估计及干扰抑制。展开更多
基金support forour work by the National Science and Technology Support Project of China (No. 2006BAK03B00)
文摘An ultra-wideband impulse radar was studied for the detection of buried life in coal mines. An improved Empirical Mode Decomposition (EMD) method based on a cross-correlation filter was proposed for reduction of multipath and noise interference. Multipath interference was first removed by cross-corre- lation filtering. Then the delays of each pulse in every echo were summed. An EMD algorithm was used for noise reduction for the total delay of each echo. The corresponding EMD results of every echo were then summed and averaged. Finally, evidence for the existence of buried life and their position were obtained from amplitude-frequency curves of the averaged EMD results. Detailed simulation experi- ments are presented to validate the effectiveness of this proposed method. The experimental results show that this method can efficiently eliminate multipath interference and reduce noise interference in echoes, which makes detection and location of buried life in coal mines more accurate.
文摘Y99-61517-433 9915280接收机算法和性能分析(含7篇文章)=Session 13:re-ceiver algorithms and performance analysis[会,英]//1998 IEEE International Conference on Communica-tions,Vol.1 of 3.—433～469(MaG)本组7篇文章。讨论了在线性时间选择性瑞利衰落信道上传输的相移键控信号的差分检测,M 元相移键控的非相干序列检测的性能分析,利用有非相干前端的接收机的预编码信号的检测,受时间相关多径现象损害的数字无线链路的截止速率,对于时变信道的强顽健自适应信号传送,一般衰落信道上线性调制信号差错率计算的一种统一方法,联合信道和数据估计及干扰抑制。
