共查询到19条相似文献,搜索用时 62 毫秒
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针对实际应用中多个非圆信号从某一先验已知角度范围内入射的情况,提出了一种采用方向域滤波的非圆信号测向算法。新算法首先利用非圆信号测向MUSIC(NC-MUISC)算法得到入射信号的空间谱,再利用信号先验入射角度范围将其空间谱函数在方向域进行滤波,得到虚拟扩展协方差矩阵,然后仿照NC-MUISC算法求得信号入射方向。仿真结果表明,新算法保持了NC-MUISC算法的阵列扩展能力,同时在分辨力和测向精度方面进一步提高,且先验角度范围越准确则算法性能越好,具有良好的实用价值。 相似文献
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近年来,针对非圆信号的测向算法已陆续提出,对这些算法的渐近性能及Cramer-Rao界的分析也已见报道,但仍未涉及模型误差对此类算法影响的分析.本文概括介绍了用于非圆信号测向的MUSIC(Multiple Signal Classification)算法,对其空间谱函数进行一阶泰勒展开,得到了测向误差的表达式,从而求得测向均方误差统计意义上的表达式.仿真实验验证了推导的正确性,并由理论结果分析了模型误差条件下测向误差与角度间隔和非圆相位差的关系. 相似文献
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非圆信号阵列测向的研究概况 总被引:3,自引:0,他引:3
阵列测向的理论与技术已日臻完善,近期研究主要集中在算法实用化以及利用信号的特殊性质等方面。BPSK等信号具有非圆特性,MSK等信号经过一定预处理也具有非圆特性,利用信号非圆特性的阵列测向问题逐渐成为一个研究热点。文章介绍了非圆信号的定义与分类,综述了非圆信号测向的现状,包括各种非圆信号测向算法及其性能分析,以及非圆信号信源个数估计等其它问题,并对其发展方向进行了预测。 相似文献
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基于扩展传播算子的非圆信号测向方法 总被引:2,自引:1,他引:2
现代通信系统大量使用非圆信号,利用经典高分辨算法对其测向没有充分利用非圆信号的信息,因而性能受限.本文提出的扩展传播算子测向算法(EPM)先对数据进行共轭扩展,再利用传播算子方法(PM)测向,充分利用了非圆信号的特点,从而可对多于阵元数的信号进行测向,分辨力和测角精度优于OPM(正交传播算子测向算法)和MUSIC算法,同时保持了PM算法的特点,不需要特征分解(ED)或奇异值分解(SVD).文中还分析了EPM算法的均方误差性能和计算复杂度,得到了均方误差的解析表达式.仿真实验验证了EPM算法的优良性能,均方误差的理论结果与仿真值相符. 相似文献
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针对传统联合估计方法计算量大、需要多维谱峰搜索的问题,该文提出了一种基于垂直阵列结构的任意初始相位非圆信号2 维DOA (Direction Of Arrival)和初相联合估计方法,利用垂直阵列特点,将3维参数估计问题转化为可并行处理的3个2维参数估计,在每一个子阵上,同时使用噪声子空间正交性和信号子空间旋转不变性,将2维参数估计进一步转化为1维估计问题,最终只需要对扩展协方差矩阵进行一次特征分解即可实现2维DOA和初相的联合估计及自动配对。该方法适用于空间信源处于过载的情形和低信噪比、短快拍环境,可估计信源数为2(M1)。数值仿真验证了该算法的有效性。 相似文献
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基于最大非圆率信号的改进SWEDE算法 总被引:1,自引:0,他引:1
SWEDE(Subspace method Without Eigen DEcomposition)算法是一种不需要协方差阵分解的波达方向估计算法。该方法能降低传统超分辨算法的计算量和复杂度,但也同时降低了均匀线性阵的可测最大信号数。本文基于非圆信号具有椭圆协方差矩阵不为零的特征,并结合SWEDE算法的基本思想,提出了一种改进SWEDE算法:NC-SWEDE算法。该算法利用最大非圆率信号的增维数据模型,相当于将线性阵的可利用阵元数加倍,因而提高了SWEDE算法可测的最大信源数,并提高了算法的分辨力和估计精度。由于引入了非圆信号的相位参数,该算法需要进行二维谱峰搜索,本文采用求极值方法达到了降维的目的。本文分别进行了NC-SWEDE算法最大可分辨信号数、不同 矩阵取法下的算法性能及与传统SWEDE算法性能比较的仿真实验,结果验证了该算法的优越性。 相似文献
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快速二维高分辨率测向方法研究 总被引:9,自引:1,他引:8
本文提出了一处基于“十“字架型阵列接收系统的二维高分辨率测向快速分维处理方法。它具有粗粒度的并行性,且运算量大大小于二维直接处理方法或已有的其它分维处理方法。文中还给出了两种改进措施来减少分维处理所带来的性能损失。最后给出了部分计算机模拟实现结果。 相似文献
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In order to solve the problem that the high computational burden of the multiple signal classification algorithm of non-circular signal (NC-MUSIC) in direction-of-arrival (DOA) estimation,a novel computationally efficient DOA estimation algorithm based on subspace rotation technique was proposed.Firstly,the partitioning of noise subspace matrix and the subspace rotation technique (SRT) were used to construct a new reduced-dimension noise subspace.Then,the two-dimensional peak searching was converted to the one-dimensional peak searching on the basis of the separation of variables and the orthogonality between the new reduced-dimension noise subspace and the space spanned by the columns of the extended manifold matrix.The proposed algorithm can enhance the computational efficiency by means of the conversion of the two-dimensional peak searching into the one-dimensional peak searching and the removal of redundant computations.Theoretical analysis and simulation results show that the proposed algorithm can reduce the computational complexity to less than 5% as compared to NC-MUSIC algorithm on the premise of ensuring the accuracy of DOA estimation.Especially,the efficiency advantage of the proposed algorithm is more obvious in scenarios where the large numbers of sensors are required. 相似文献
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Researchers have recently shown an increased interest in estimating the direction-of-arrival (DOA) of wideband noncircular sources, but existing studies have been restricted to subspace-based methods. An off-grid sparse recovery-based algorithm is proposed in this paper to improve the accuracy of existing algorithms in low signal-to-noise ratio situations. The covariance and pseudo covariance matrices can be jointly represented subject to block sparsity constraints by taking advantage of the joint sparsity between signal components and bias. Furthermore, the estimation problem is transformed into a single measurement vector problem utilizing the focused operation, resulting in a significant reduction in computational complexity. The proposed algorithm's error threshold and the Cramer–Rao bound for wideband noncircular DOA estimation are deduced in detail. The proposed algorithm's effectiveness and feasibility are demonstrated by simulation results. 相似文献
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Li Ping'an Yu Bianzhang Sun Jincai 《电子科学学刊(英文版)》1996,13(4):319-324
In array signal processing, 2-D spatial-spectrum estimation is required to determine DOA of multiple signals. The circular array of sensors is found to possess several nice properties for DOA estimation of wide-band sources. C. U. Padmini, et al.(1994) had suggested that the frequency-direction ambiguity in azimuth estimation of wide-baud signals received by a uniform linear array (ULA) can be avoided by using a circular array, even without the use of any delay elements. In 2-D spatial-spectrum estimation for wide-band signals, the authors find that it is impossible to avoid the ambiguity in source frequency-elevation angle pairs using a circular array. In this paper, interpolated circular arrays are used to perform 2-D spatial-spectrum estimation for wide-band sources. In the estimation, a large aperture circular array (Υ>λmin/2) is found to possess superior resolution capability and robustness. 相似文献
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针对传统的子空间类波达方向(Direction of Arrival,DOA)估计算法只适用于入射信号个数少于天线数的局限性,利用现代通信系统中常用的非圆信号实值特性,提出了一种虚拟阵列多重信号分类法(Virtual Array Based Multiple Signal Classification,VA-MUSIC)。该方法通过对阵列输出信号进行共轭重构和合并,获得虚拟阵列来增加阵列的有效孔径。更进一步,结合空间平滑技术有效地解决了相干信号的DOA估计问题。与传统的MUSIC算法相比,新算法不仅可以增加最大可估计信源数,而且在DOA估计精度、信号源角分辨能力等方面均有明显的优势。计算机仿真验证了该算法的有效性和优越性。 相似文献
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A new algorithm for 2-D DOA estimation 总被引:1,自引:0,他引:1
In this paper we present a new algorithm to estimate the 2-D direction of arrival (DOA) of narrowband sources lying in the far field of the array. The array consists of matched co-directional triplets, and can be considered as an extension of the 1-D ESPRIT scenario to 2-D. The proposed approach is simple and direct and does not require a search procedure or initialization. Existing algorithms require a search to match the correct elevation and azimuth angles and are computationally more expensive. This technique automatically pairs the azimuth and elevation angles by marking them. The computational complexity is twice that of 1-D ESPRIT. Simulation results and comparisons with other existing algorithms are presented to demonstrate the performance of the proposed technique. 相似文献
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This paper presents a new array structure for estimating two-dimensional (2-D) direction-of-arrivals (DOAs). The structure is called Y-shaped array, which has 10% better accuracy potential than the newly-developed L-shaped array. A great merit is its ability to estimate 2-D DOAs whichever directions the arriving signals come from, compared with L-shaped array whose performance depends on DOAs. Simulation results are given to demonstrate the performance of the new array. 相似文献