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用任意阵实现二维到达角和极化的联合估计 总被引:2,自引:5,他引:2
基于四阶累积量和ESPRIT算法提出一种新的任意高斯噪声环境上多个独立空间信号二维到达角和极化的联合估计方法。该算法的阵列由和坐标轴方向一致的偶极子对组成,各偶极子对的排列结构任意。计算机模拟结果证实了方法的可行性。 相似文献
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The two‐dimensional estimating signal parameter via rotational invariance techniques (2D‐ESPRIT) algorithm is a classical method to estimate parameters of the two‐dimensional geometric theory of diffraction (2D‐GTD) model. While as signal‐to‐noise‐ratio (SNR) decreases, the parameter estimation performance of 2D‐ESPRIT algorithm is severely influenced. To solve this problem, a performance‐enhanced 2D‐ESPRIT algorithm is proposed in this article. The improved 2D‐ESPRIT algorithm combines the conjugate data with the original back‐scattered data and obtains a novel covariance matrix by squaring the original total covariance matrix. Simulation results indicate that the improved algorithm has a better noise robustness and a more stable parameter estimation performance than the classical ESPRIT algorithm and the classical TLS‐2D‐ESPRIT algorithm. To further validate the superiority of the improved 2D‐ESPRIT algorithm, reconstructed radar cross section (RCS) is presented in this article. Compared with the classical 2D‐ESPRIT algorithm, the proposed algorithm presents higher RCS fitting precision. Furthermore, the impacts of other factors on parameter estimation, such as matrix pencil parameters and paring parameters, are also studied in this article. 相似文献
5.
Accurate attitude estimation is crucial for Unmanned Aerial Vehicles (UAVs) in order to facilitate automated activities such as landing or trajectory tracking. Recently antenna array based communication systems have been installed in UAVs. This array structure can also be applied for attitude estimation by computing the line-of-sight (LOS) path between the base station and UAV. In this paper, we propose a complete framework for attitude estimation by exploiting 3D LOS vector obtained from the antenna array system. We present all the steps to incorporate the estimated LOS vector into the TRIaxial Attitude Determination (TRIAD), QUaternion ESTimator (QUEST) and Kalman algorithms. As an additional contribution, the error covariance matrix of the LOS vector is analytically calculated by first finding the phase shift mean squared error using the known perturbation model from Singular Value Decomposition and assuming that the antenna array measured data error can be modeled as a circularly symmetric white noise. We evaluate five array configurations via Monte Carlo simulations. We show that array configurations that provide orthogonal components of the LOS vector achieve a better performance. The usage of more than three pairs of antennas to improve the estimation of the LOS vector is also proposed for low and intermediate signal-to-noise ratio regimes. 相似文献
6.
The use of subspace and Matrix Algebra (MA) methods for estimating Power Quality Indices (PQIs) as defined by IEEE Std 1459-2010 is relatively new. For this reason there is room for further research about these methods and their efficiency applied to estimating PQIs. This document presents the design of a Virtual Instrument (VI) based on modern subspace, MA and Least Square (LS) techniques with a Kalman Filter (KF) for estimating PQIs. Further we claim that the efficiency of the subspace method is comparable to the Fourier based methods in typical power system analysis. Simulation and experiments are conducted to further compare the performance of this VI with other VI's which do not use the KF. We also compare this VI with VI's that use the classical Fast Fourier Transform (FFT) based method of estimation. 相似文献
7.
LIU Wen-hong QIU Tian-shuang HU Ting-ting TANG Hong 《中国矿业大学学报(英文版)》2007,17(1):30-34
The non-Gaussian α-stable distribution is introduced to model impulsive noise. Based on the theory of fractional lower order statistics (FLOS), the fractional lower order cross-covariance (FLOCC) sequence for two received signals is obtained and the fractional lower order cross-covariance spectrum (FLOCCS) can be approached by taking a Fourier transform for the FLOCC sequence. When the FLOCCS is treated as a sequence in the time domain, the problem of multipath time delay estimation (TDE) may be converted into one on multi-frequencies estimation or directions of arrival estimation. Accordingly, the high resolution multipath TDE can be realized with the ESPRIT technology. This idea on multipath TDE is referred to as FLOCCS-ESPRIT in this paper. Computer simulations show that this method has good performance both in a Gaussian noise and in an impulsive noise environment. 相似文献
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This paper presents application of parametric techniques (Estimation of signal parameter by rotational invariance techniques (ESPRIT), Root multiple signal classification (Root MUSIC)) for the estimation of harmonics/inter harmonics produced by wind generator under constant, variable rotor speed, load imbalance. Accuracy of estimation by parametric techniques is checked on synthetic signal as well as signal extracted from DFIG based standalone system with constant rotor speed and balanced load condition. Further sliding window concept is applied to parametric techniques to estimate the harmonics/inter harmonics under variable rotor speed and load unbalance. Series of simulation results demonstrate the advantages of the sliding window ESPRIT over sliding window Root MUSIC in the estimation of harmonics and inter harmonics under variable rotor speed as well as load unbalance condition. 相似文献
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An eigenstructure-based 2D DOA estimation method using dual-size spatial invariance array 总被引:1,自引:0,他引:1
YANG XueYa CHEN BaiXiao & CHEN YunHai National Key Lab of Radar Signal Processing Xidian University Xi’an China 《中国科学:信息科学(英文版)》2011,(1):163-171
A sparse planar array vertically placed in y-z plane is proposed to improve the angle estimation accuracy of sources in low angle region with reflection multipath.With two sizes of spatial invariances along both dimensions,the array estimates the azimuth and elevation angles using unitary ESPRIT(estimation of signal parameters via rotational invariance techniques).The first spatial invariance with a displacement of half-wavelength yields unambiguous coarse estimates of high-variance,while the second spatial... 相似文献
10.
一种基于L阵的二维解相干测向算法 总被引:1,自引:0,他引:1
本文对高斯白噪声环境下基于L型阵列二维测向的ESPRIT算法进行了改进.该算法利用阵列结构特点通过平滑原理获得3个互相关矩阵,然后由3个矩阵构造一个特殊大矩阵并对其进行奇异值分解来估计信号子空间,最后利用2D-ESPRIT方法实现二维测向.该算法估计精度高,运算量小,能够对相干信号进行估计. 相似文献