A novel adaptive detector for airborne radar space-time adaptive detection （STAD） in partially homogeneous environments is proposed. The novel detector combines the numerically stable Krylov subspace technique and d...A novel adaptive detector for airborne radar space-time adaptive detection （STAD） in partially homogeneous environments is proposed. The novel detector combines the numerically stable Krylov subspace technique and diagonal loading technique, and it uses the framework of the adaptive coherence estimator （ACE）. It can effectively detect a target with low sample support. Compared with its natural competitors, the novel detector has higher proba- bility of detection （PD）, especially when the number of the training data is low. Moreover, it is shown to be practically constant false alarm rate （CFAR）.展开更多
An adaptive algorithm named low complexity phase off- set estimation （LC-POE） is proposed for orthogonal frequency division multiplexing （OFDM） signals. Depending on the requirement, the estimation procedure is di...An adaptive algorithm named low complexity phase off- set estimation （LC-POE） is proposed for orthogonal frequency division multiplexing （OFDM） signals. Depending on the requirement, the estimation procedure is divided into several scales to accelerate the adaptive convergence speed and ensure the estimation accuracy. The true phase offset is estimated through shrinking the detection range and raising the resolution scale step by step. Both the convergence performance and complexity are discussed in the paper. Simulation results show the effectiveness of the proposed algorithm. The LC-POE algorithm is promising in the application of OFDM systems.展开更多
The problem of adaptive detection in the situation of signal mismatch is considered; that is, the actual signal steering vector is not aligned with the nominal one. Two novel tunable detectors are proposed. They can c...The problem of adaptive detection in the situation of signal mismatch is considered; that is, the actual signal steering vector is not aligned with the nominal one. Two novel tunable detectors are proposed. They can control the degree to which the mismatched signals are rejected. Remarkably, it is found that they both cover existing famous detectors as their special cases. More importantly, they possess the constant false alarm rate（CFAR）property and achieve enhanced mismatched signal rejection or improved robustness than their natural competitors. Besides, they can provide slightly better matched signals detection performance than the existing detectors.展开更多
分布式相参雷达在抗干扰和目标探测性能方面具有明显优势,但分布式构型带来的栅瓣问题给目标到达方向(direction of arrival,DOA)估计带来很大的困难。在均匀分布式相参阵列的基础上,拓展和差波束形成(sum and difference beamforming,S...分布式相参雷达在抗干扰和目标探测性能方面具有明显优势,但分布式构型带来的栅瓣问题给目标到达方向(direction of arrival,DOA)估计带来很大的困难。在均匀分布式相参阵列的基础上,拓展和差波束形成(sum and difference beamforming,SDB)方法至分布式阵列的栅瓣区域,并采用双指向法分析鉴角曲线(angular response curve,ARC)特性,提出一种基于多载频自适应SDB(multi-frequency adaptive SDB,MF-ASDB)的解模糊测角方法。该方法在不同频点下利用密集栅瓣辅助扫描检测,通过ASDB方法计算模糊主值后,将其拓展得到包含目标真实角度的DOA模糊值;根据频率与栅瓣周期之间的角度偏移关系,使用最小二乘方法实现DOA解模糊。仿真结果验证了所提方法的有效性。展开更多
为了得到稳定的波束方向图、进一步提高极化敏感阵列的滤波性能,文中提出了一种极化域-空域联合的四元数幅度相位估计(Q-APES,Quaternion-Amplitude and Phase EStimation)自适应波束形成算法。首先,利用四元数信号模型很好的保持了两...为了得到稳定的波束方向图、进一步提高极化敏感阵列的滤波性能,文中提出了一种极化域-空域联合的四元数幅度相位估计(Q-APES,Quaternion-Amplitude and Phase EStimation)自适应波束形成算法。首先,利用四元数信号模型很好的保持了两分量阵列各阵元输出信号分量之间固有的正交特性,使得该模型较传统的长矢量模型更适合于极化敏感阵列信号处理。然后,将纯空域的APES算法拓展到极化域-空域联合处理中,给出了Q-APES算法的理论推导和分析,得出了四元数最优滤波权向量,并通过仿真实验验证了文中算法的有效性。计算机仿真结果表明,在强期望信号、低采样快拍数或是入射干扰信号与期望信号相干的情况下,文中算法都可以很好的实现极化域-空域联合自适应滤波。展开更多
基金supported by the National Natural Science Foundation of China(609250056110216961501505)
文摘A novel adaptive detector for airborne radar space-time adaptive detection （STAD） in partially homogeneous environments is proposed. The novel detector combines the numerically stable Krylov subspace technique and diagonal loading technique, and it uses the framework of the adaptive coherence estimator （ACE）. It can effectively detect a target with low sample support. Compared with its natural competitors, the novel detector has higher proba- bility of detection （PD）, especially when the number of the training data is low. Moreover, it is shown to be practically constant false alarm rate （CFAR）.
基金supported by the National Natural Science Foundation of China (60972072)the National Science and Technology Major Projects: the New Generation Broadband Wireless Mobile Communication Network (2009ZX03003-03)the "111 Project" of China (B08038)
文摘An adaptive algorithm named low complexity phase off- set estimation （LC-POE） is proposed for orthogonal frequency division multiplexing （OFDM） signals. Depending on the requirement, the estimation procedure is divided into several scales to accelerate the adaptive convergence speed and ensure the estimation accuracy. The true phase offset is estimated through shrinking the detection range and raising the resolution scale step by step. Both the convergence performance and complexity are discussed in the paper. Simulation results show the effectiveness of the proposed algorithm. The LC-POE algorithm is promising in the application of OFDM systems.
基金supported by the National Natural Science Foundation of China(6110216960925005)
文摘The problem of adaptive detection in the situation of signal mismatch is considered; that is, the actual signal steering vector is not aligned with the nominal one. Two novel tunable detectors are proposed. They can control the degree to which the mismatched signals are rejected. Remarkably, it is found that they both cover existing famous detectors as their special cases. More importantly, they possess the constant false alarm rate（CFAR）property and achieve enhanced mismatched signal rejection or improved robustness than their natural competitors. Besides, they can provide slightly better matched signals detection performance than the existing detectors.
文摘分布式相参雷达在抗干扰和目标探测性能方面具有明显优势,但分布式构型带来的栅瓣问题给目标到达方向(direction of arrival,DOA)估计带来很大的困难。在均匀分布式相参阵列的基础上,拓展和差波束形成(sum and difference beamforming,SDB)方法至分布式阵列的栅瓣区域,并采用双指向法分析鉴角曲线(angular response curve,ARC)特性,提出一种基于多载频自适应SDB(multi-frequency adaptive SDB,MF-ASDB)的解模糊测角方法。该方法在不同频点下利用密集栅瓣辅助扫描检测,通过ASDB方法计算模糊主值后,将其拓展得到包含目标真实角度的DOA模糊值;根据频率与栅瓣周期之间的角度偏移关系,使用最小二乘方法实现DOA解模糊。仿真结果验证了所提方法的有效性。
文摘为了得到稳定的波束方向图、进一步提高极化敏感阵列的滤波性能,文中提出了一种极化域-空域联合的四元数幅度相位估计(Q-APES,Quaternion-Amplitude and Phase EStimation)自适应波束形成算法。首先,利用四元数信号模型很好的保持了两分量阵列各阵元输出信号分量之间固有的正交特性,使得该模型较传统的长矢量模型更适合于极化敏感阵列信号处理。然后,将纯空域的APES算法拓展到极化域-空域联合处理中,给出了Q-APES算法的理论推导和分析,得出了四元数最优滤波权向量,并通过仿真实验验证了文中算法的有效性。计算机仿真结果表明,在强期望信号、低采样快拍数或是入射干扰信号与期望信号相干的情况下,文中算法都可以很好的实现极化域-空域联合自适应滤波。
基金2013 Major National Development of Special Equipment(No.2013YQ160487)2013 Beijing University of Post and Communication 863 Program(Nos.2013AA013403,2012AA010407)the Natural Science Foundation fo China(No.61007043)
