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基于互Wigner-Ville分布的到达角估计 总被引:4,自引:1,他引:3
研究了对线性调频信号的到达角估计;提出了基于互Wigner-Ville分布(XWVD)估计信号到达角的方法.通过时频分布,在时频面上进行信号预分选;根据XWVD时频脊点上的相位获得信号时延,从而获得信号到达角.该算法可实现多信号分辨,也可实现对时变频率信号的到达角估计.计算机仿真结果证实了该算法的有效性. 相似文献
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针对现有商用Wi-Fi接入点(Access Point,AP)天线的个数限制了基于多天线到达角(Angle of Arrival,AoA)高精度定位的问题,本文提出了一种基于Wi-Fi的室内实时角度定位算法.提出了基于Wi-Fi系统的角度估计算法,能够在天线数量以及快拍数少的情况下快速地估计直视(Line of Sight,LoS)路径的到达角,保证定位的实时性;利用IEEE 802.11 Saleh-Valenzuela(S-V)信道模型分析了多径信号对直达信号能量谱峰的影响;为了提高定位精度提出了基于天线选择的多AP联合定位算法;为了验证系统的有效性搭建了实时定位演示系统.本文通过实际测试验证了所提算法可以达到67%1.2m的定位精度,定位时延在0.5s以内. 相似文献
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动目标多径回波的时延、到达角和多普勒频率联合估计 总被引:1,自引:0,他引:1
动目标回波的时延、到达角与多普勒频率等参数,都是定位与跟踪目标所需的重要参数。本文针对动目标多径回波的参数估计问题,利用照射信号的周期重复性建立了具有旋转不变结构的阵列接收信号模型,并将PRO-ESPRIT算法应用于该信号模型,从而利用模型中的旋转不变因子及其对应的特征向量估计得到各多普勒频率、时延和到达角参数。这一方法对阵列形式没有特殊要求;与已有的联合估计方法相比,多参数联合估计时无需高维搜索或迭代,估得的对应相同回波的信号参数自动配对;在照射信号未知及存在相同多普勒频率参数的条件下,仍具适用性。计算机仿真结果证实了该方法的有效性。 相似文献
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频率、二维到达角和极化联合估计 总被引:22,自引:1,他引:21
在宽频段内多信号多参量联合估计已成为许多研究课题,例如,。未知辐射源识别,有效对消等等的重要研究内容,信号频率与二维到达角、二维到达角与极化的联合估计已开展研究,但信号频率二维到达角和极化联合估计的研究尚未见报导,本文提出了利用交叉偶极子平面阵和ESPRIT算法实现频率、二维到达角和极化联合估计的新方法,分析了算法结构,计算机模拟结果证实了算法的有效性。 相似文献
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Fangqiu Wang Chenghua Wang Shengkui Zhou 《International Journal of Electronics》2013,100(10):1765-1788
Impulse radio ultra-wideband (IR-UWB) ranging and positioning require accurate estimation of time-of-arrival (TOA) and direction-of-arrival (DOA). With receiver of two antennas, both of the TOA and DOA parameters can be estimated via two-dimensional (2D) propagator method (PM), in which the 2D spectral peak searching, however, renders much higher computational complexity. This paper proposes a successive PM algorithm for joint TOA and DOA estimation in IR-UWB system to avoid 2D spectral peak searching. The proposed algorithm firstly gets the initial TOA estimates in the two antennas from the propagation matrix, then utilises successively one-dimensional (1D) local searches to achieve the estimation of TOAs in the two antennas, and finally obtains the DOA estimates via the difference in the TOAs between the two antennas. The proposed algorithm, which only requires 1D local searches, can avoid the high computational cost in 2D-PM algorithm. Furthermore, the proposed algorithm can obtain automatically paired parameters and has better joint TOA and DOA estimation performance than conventional PM algorithm, estimation of signal parameters via rotational invariance techniques algorithm and matrix pencil algorithm. Meanwhile, it has very close parameter estimation to that of 2D-PM algorithm. We have also derived the mean square error of TOA and DOA estimation of the proposed algorithm and the Cramer-Rao bound of TOA and DOA estimation in this paper. The simulation results verify the usefulness of the proposed algorithm. 相似文献
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IR-UWB 系统中基于 root-MUSIC 算法的 TOA 和 DOA 联合估计简 总被引:1,自引:0,他引:1
针对二维多重信号分类算法可以估计出系统的到达时间(TOA, time-of-arrival)和波达方向(DOA, direction- of-arrival)参数,但需要复杂度非常高的二维谱峰搜索这一问题,提出了IR-UWB系统中基于求根MUSIC(root-MUSIC)的TOA和DOA联合估计算法,该算法对接收信号的频域形式建模,先估计出TOA,然后由TOA的差值计算出DOA,从而实现TOA和DOA的联合估计。该算法不需谱峰搜索,可直接给出估计参数的闭式解,还可实现参数配对。还推导了参数估计的误差方差。仿真结果表明,该算法的参数估计性能明显优于矩阵束算法、传播算子算法以及基于旋转不变技术估计信号参数算法,并且非常接近于2D-MUSIC算法,但该算法的复杂度却远远低于2D-MUSIC算法。 相似文献
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基于TOA和DOA联合估计的UWB定位方法 总被引:5,自引:1,他引:4
对于UWB定位系统而言,利用时间参数估计信号源的位置需要多个参考节点,这样增加了系统的开销。如果参考节点既能估计目标源的时间参数又能估计角度参数,理论上一个参考节点就可以确定目标源的位置。该文提出一种UWB系统TOA(到达时间)和DOA(到达角度)参数联合估计的定位方法,该方法使用矩阵束算法估计出时间参数和角度参数,进而得到目标的相对坐标。该方法通过单个接收机就可以确定目标的位置,减少了定位系统负担。仿真实验证实了该方法估计时延和角度精度较高,而且定位精度能够达到厘米级,是一种简单可行的UWB系统定位方法。 相似文献
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This paper addresses the problem of joint time of arrival (TOA) and direction of arrival (DOA) estimation in impulse radio ultra‐wideband systems with a two‐antenna receiver and links the joint estimation of TOA and DOA to the sparse representation framework. Exploiting this link, an orthogonal matching pursuit algorithm is used for TOA estimation in the two antennas, and then the DOA parameters are estimated via the difference in the TOAs between the two antennas. The proposed algorithm can work well with a single measurement vector and can pair TOA and DOA parameters. Furthermore, it has better parameter‐estimation performance than traditional propagator methods, such as, estimation of signal parameters via rotational invariance techniques algorithms matrix pencil algorithms, and other new joint‐estimation schemes, with one single snapshot. The simulation results verify the usefulness of the proposed algorithm. 相似文献
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Time-of-arrival (TOA) and direction-of-arrival (DOA) are key parameters in the impulse radio ultra wideband (IR-UWB) positioning system with a two-antennas receiver. A two-dimensional (2D) multiple signal classification (MUSIC) algorithm, which requires the 2D spectral peak search, can be used to estimate the parameters, but it has much higher computational complexity. This paper proposes a successive MUSIC algorithm for joint TOA and DOA estimation in IR-UWB system to avoid 2D spectral peak search. The proposed algorithm obtains the initial estimate of TOA corresponding to the first antenna via Root-MUSIC, and simplifies the 2D global search into successive one-dimensional searches to achieve the estimation of TOAs in the two antennas. It then estimates the DOA parameters via the difference of the TOAs between the two antennas. The proposed algorithm can get the parameters paired automatically, and has a much lower complexity than 2D-MUSIC algorithm. In addition, we have derived the mean square error of TOA and DOA estimation of the proposed algorithm and the Cramer–Rao bound of TOA and DOA estimation in the paper. The simulation results show that the parameter estimation performance of the proposed algorithm is better than that of Root-MUSIC, and is almost the same as that of 2D-MUSIC algorithm. Moreover, it has much better performance than matrix pencil algorithm, propagator method and estimation of signal parameters via rotational invariance techniques algorithm. 相似文献
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当存在离格信号时,基于稀疏表示的波达角(DOA)估计算法性能损失严重.为解决这个问题,在对接收数据协方差矩阵进行Khatri-Rao积变换的基础上,推导了离格信号网格偏离量与紧邻信号原子系数之间的关系,提出了一种单一离格信号DOA估计方法.为提高对邻近离格信号DOA的估计性能,利用矩阵的广义逆性质提出了基于多原子系数的联合估计方法.仿真实验表明,单一离格信号DOA估计方法在低信噪比下有较好的性能,联合估计方法在高信噪比条件下对邻近离格信号DOA有较高的估计精度,同时所提算法估计性能几乎不受网格划分间距的影响,可以通过增大网格间距降低算法运算量.相关研究对阵列天线DOA估计具有一定的参考价值. 相似文献
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The assumption that observed signals are ideally received is commonly used in the literature on time-delay estimation. However, for practical digital receivers, the received radio-frequency signals are usually downconverted to the baseband and digitized by analog-to-digital converters. Because inaccurate and unstable system clocks are used, frequency and phase offsets are usually induced by the frequency-mixing procedure, whereas a time stretch may ensue from the sampling procedure. The aforementioned problems are almost inevitable for incoherent reception systems. Therefore, the neglect of imperfect reception for incoherent systems may reduce the performance of conventional time-delay estimation methods. In this paper, employing refined signal models developed specifically for incoherent time-delay estimation in active and passive systems, the corresponding joint maximum likelihood estimates of time delay and system-clock frequency error are proposed. The Cramér–Rao lower bounds (CRLBs) on time-delay and clock frequency error estimations are also derived. The performance of the proposed time-delay estimators can be improved for frequency/phase offsets and time stretches, approaching the performance of the CRLBs in scenarios of moderate and high signal-to-noise ratios. Furthermore, both CRLBs analysis and simulation results verify that the accuracy of the proposed time-delay estimator is unaffected by the performance of the system clock in moderate scenarios. 相似文献
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针对宽带信号非平稳特性,以及常用宽带DOA估计算法要求信源个数是已知的情况,提出一种新的基于空间任意阵的非平稳信号DOA估计算法。首先,通过短时傅里叶变换将信号转为频域表示,然后构造阵列频域数据模型,最后利用短时功率谱矩阵的联合对角化特性实现宽带信号的波达方向估计。本文对提出的算法进行了理论分析,并在常见阵型(如线阵、十字阵)上进行了仿真和性能分析,仿真结果表明该算法可高分辨率地估计出DOA,并且估计误差小。相对于已有的MUSIC谱估计方法,该算法无需进行信源个数估计,更具实用性。 相似文献