基于极化敏感阵列的参数估计及波束形成算法研究
发布时间：2018-12-18 05:57
【摘要】：极化敏感阵列(PSA)可以获取入射电磁波的极化状态,相比于标量阵列其具有诸多性能优势,成为近些年来的热点研究课题之一。然而目前针对极化阵列的处理方法,大多是传统阵列处理方法的直接拓展,没有过多利用极化阵列的特殊流型结构,极化阵列处理的性能还有待进一步提高。针对这一问题,本文主要针对极化阵列参数估计和波束形成的方法展开研究,充分利用电偶极子对的正交结构,且基于一种分布式极化阵列布阵模型给出了参数估计和波束形成的方法,并通过计算机仿真给出了实验结果。针对极化阵列参数估计,同时考虑入射非相干和相干信源的情况。针对非相干信源,给出了常见的Lv-Music和极化ESPRIT参数估计算法,并利用两分量阵列的流型结构,基于四元数Music方法完成了参数估计。计算机仿真结果表明基于四元数的方法多参数估计性能优于基于复数的方法。针对相干信源,给出了极化阵列空间平滑和极化平滑解相干算法,并给出了二者的改进方法。仿真结果表明文中改进算法具有更低的参数估计均方根误差和更好的角度分辨力,且改进的极化平滑算法还具有对噪声的适应性。针对极化阵列波束形成,介绍了联合滤波的原理和准则,给出了常规的波束形成和基于四元数的波束形成方法。基于特征空间的思想,推导了导数约束和零点约束条件下的最优加权矢量,并通过仿真验证不同约束条件对联合滤波波束方向图和滤波性能的影响。利用两分量极化阵列共点分量之间固有的正交特性,推导了基于四元数的波束形成,包括Q-MVDR和Q-APES算法,给出了算法的理论推导得到了最优加权矢量的表达式。计算机仿真结果表明,Q-APES算法在目标信号功率较大、快拍数较少、干扰与目标信号相干的情况下都具有稳定的波束图,且在极化阵列存在指向误差时也表现具有一定的稳健性。为了有效减少极化阵列共点分量之间互耦的影响,降低硬件实现的成本和算法处理的复杂度,考虑将两分量极化阵列阵元各分量在空间交替分散放置。给出了一种分布式极化阵列的布阵模型,利用其流型结构特点完成了参数估计和波束形成方法的理论推导,并与两分量共点极化阵列和传统的标量阵列分别在不同条件下对比了参数估计和联合滤波的性能。
[Abstract]:Polarization-sensitive array (PSA) can obtain the polarization state of incident electromagnetic wave. Compared with scalar array, it has many performance advantages and has become one of the hot research topics in recent years. However, most of the current processing methods for polarization array are the direct expansion of traditional array processing methods, and the performance of polarization array processing needs to be further improved without making too much use of the special flow pattern structure of polarization array. In order to solve this problem, this paper mainly studies the parameter estimation of polarization array and the beamforming method, and makes full use of the orthogonal structure of electric dipole pair. The method of parameter estimation and beamforming based on a distributed polarization array model is given, and the experimental results are given by computer simulation. For the parameter estimation of polarization array, the incident incoherent and coherent sources are considered at the same time. For incoherent sources, common Lv-Music and polarimetric ESPRIT parameter estimation algorithms are presented, and the parameters are estimated based on quaternion Music method using the flow pattern structure of two-component array. The results of computer simulation show that the performance of multi-parameter estimation based on quaternion is better than that based on complex number. For coherent sources, the spatial smoothing and polarimetric smoothing algorithms of polarimetric array are presented, and the improved methods are given. The simulation results show that the improved algorithm has lower root mean square error and better angular resolution, and the improved polarization smoothing algorithm is adaptive to noise. Aiming at polarization array beamforming, the principle and criterion of joint filtering are introduced, and the conventional beamforming and quaternion based beamforming methods are presented. Based on the idea of feature space, the optimal weighted vector with derivative constraint and zero constraint is derived, and the effects of different constraints on the beam pattern and filtering performance of joint filtering are verified by simulation. Based on the inherent orthogonality between the common point components of a two-component polarization array, a quaternion based beamforming algorithm, including Q-MVDR and Q-APES algorithms, is derived. The theoretical derivation of the algorithm is given to obtain the expression of the optimal weighted vector. The computer simulation results show that the Q-APES algorithm has a stable beam diagram when the signal power of the target is large, the number of rapids is small, and the interference is coherent with the target signal. And the polarization array has some robustness when there is pointing error. In order to reduce the influence of mutual coupling between common point components of polarization array, reduce the cost of hardware implementation and the complexity of algorithm processing, we consider placing the components of two-component polarization array alternately in space. An array model of distributed polarization array is presented. The theoretical derivation of parameter estimation and beamforming method is completed by using its flow pattern structure. The performance of parameter estimation and joint filtering are compared with two-component co-point polarization array and traditional scalar array under different conditions.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN911.7
本文编号：2385458
[Abstract]:Polarization-sensitive array (PSA) can obtain the polarization state of incident electromagnetic wave. Compared with scalar array, it has many performance advantages and has become one of the hot research topics in recent years. However, most of the current processing methods for polarization array are the direct expansion of traditional array processing methods, and the performance of polarization array processing needs to be further improved without making too much use of the special flow pattern structure of polarization array. In order to solve this problem, this paper mainly studies the parameter estimation of polarization array and the beamforming method, and makes full use of the orthogonal structure of electric dipole pair. The method of parameter estimation and beamforming based on a distributed polarization array model is given, and the experimental results are given by computer simulation. For the parameter estimation of polarization array, the incident incoherent and coherent sources are considered at the same time. For incoherent sources, common Lv-Music and polarimetric ESPRIT parameter estimation algorithms are presented, and the parameters are estimated based on quaternion Music method using the flow pattern structure of two-component array. The results of computer simulation show that the performance of multi-parameter estimation based on quaternion is better than that based on complex number. For coherent sources, the spatial smoothing and polarimetric smoothing algorithms of polarimetric array are presented, and the improved methods are given. The simulation results show that the improved algorithm has lower root mean square error and better angular resolution, and the improved polarization smoothing algorithm is adaptive to noise. Aiming at polarization array beamforming, the principle and criterion of joint filtering are introduced, and the conventional beamforming and quaternion based beamforming methods are presented. Based on the idea of feature space, the optimal weighted vector with derivative constraint and zero constraint is derived, and the effects of different constraints on the beam pattern and filtering performance of joint filtering are verified by simulation. Based on the inherent orthogonality between the common point components of a two-component polarization array, a quaternion based beamforming algorithm, including Q-MVDR and Q-APES algorithms, is derived. The theoretical derivation of the algorithm is given to obtain the expression of the optimal weighted vector. The computer simulation results show that the Q-APES algorithm has a stable beam diagram when the signal power of the target is large, the number of rapids is small, and the interference is coherent with the target signal. And the polarization array has some robustness when there is pointing error. In order to reduce the influence of mutual coupling between common point components of polarization array, reduce the cost of hardware implementation and the complexity of algorithm processing, we consider placing the components of two-component polarization array alternately in space. An array model of distributed polarization array is presented. The theoretical derivation of parameter estimation and beamforming method is completed by using its flow pattern structure. The performance of parameter estimation and joint filtering are compared with two-component co-point polarization array and traditional scalar array under different conditions.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN911.7
【参考文献】
相关期刊论文 前1条
1 李会勇;刘芳;王宇;樊勇;何子述;;极化域-空域联合的四元数APES波束形成算法[J];信号处理;2014年10期
，本文编号：2385458
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