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非视距误差的TDOA/AOA混合定位算法 总被引:2,自引:0,他引:2
在非视距(NLOS)误差时,无线网络的目标定位性能急剧下降。提出一种针对NLOS误差的TDOA/AOA混合定位算法,首先利用量测值多项式拟合的Wylie鉴别算法辨别出具有NLOS误差的基站,根据NLOS附加时延的统计特性估计出附加时延的均值和方差,并重构到达时间差(TDOA)测量值;然后采用基于泰勒级数展开的TDOA/AOA混合定位算法,得出无线网络联合目标定位的位置估计值。仿真结果证实,该方法在存在NLOS误差下能有效提高无线网络的目标定位精度。 相似文献
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Li Cong Weihua Zhuang 《Wireless Communications, IEEE Transactions on》2002,1(3):439-447
This paper proposes a mobile user location scheme for wideband code-division multiple-access (CDMA) wireless communication systems. To achieve high location accuracy and low cost of the mobile receiver, the location scheme combines the time difference of arrival (TDOA) measurements from the forward link pilot signals with the angle of arrival (AOA) measurement from the reverse link pilot signal. High chip rates in wideband CDMA systems facilitate accurate TDOA measurements, and a smart antenna used at the home base station (BS) can provide accurate AOA measurement in a macrocell environment. A two-step least square location estimator is developed based on a linear form of the AOA equation in the small error region. Numerical results demonstrate that the proposed hybrid TDOA/AOA location scheme gives a much higher location accuracy than TDOA only location, when the number of base stations is small and/or when the TDOA measurements have a relatively poor accuracy 相似文献
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一种改进的NLOS环境下的TDOA/AOA混合定位算法 总被引:2,自引:1,他引:2
在蜂窝移动通信系统中,利用基站测量的到达时间差(TDOA)和电波到达角(AOA)的混合定位方法能够比传统的TDOA方法提供更高的定位精度。但是在非视距(NLOS)条件下,当AOA的测量误差超过一定值时,定位的误差仍然很大。该文根据NLOS传播环境下附加传播时延服从指数分布的特性,估计附加时延的均值和方差,对TDOA测量值进行重构,再以AOA方法进行辅助定位。仿真结果表明,该算法能显著提高传统的TDOA和TDOA/AOA方法在NLOS传播环境下的定位精度。 相似文献
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Estimating a location of mobile station is considerable interest in wireless cellular systems. This letter deals with a hybrid time-of-arrival (TOA)/angle-of-arrival (AOA) mobile location estimation under relatively low signal-to-noise ratio and moderately nonline-of-sight (NLOS) scenarios. To reduce location estimation errors, a robust estimator for hybrid TOA/AOA location systems is proposed by using the minimax mean-squared error (MSE) criterion. Simulation results demonstrate that the proposed estimator significantly outperforms the other least squares estimators. 相似文献
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Wireless Personal Communications - Hybrid Mobile ad hoc network (H-MANET) is a network in which MANET is connected to the Internet using some special nodes called Internet Gateways (IGs). Previous... 相似文献
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Super-Resolution Time Delay Estimation in Multipath Environments 总被引:1,自引:0,他引:1
Feng-Xiang Ge Dongxu Shen Yingning Peng Li V.O.K. 《IEEE transactions on circuits and systems. I, Regular papers》2007,54(9):1977-1986
The super-resolution time delay estimation in multipath environment is very important for many applications. Conventional super-resolution approaches can only deal with signals with wideband and flat spectra. In this paper, we propose a novel super-resolution time delay estimation method that can treat signals with narrowband spectra. In our method, the time delay estimation is first transformed into the frequency domain, in which the problem is converted into the parameter estimation of sinusoidal signals with lowpass envelopes. Then a MUSIC-type algorithm taking account of the envelope variation is applied to achieve the super-resolution estimation. Time delay estimation in active and passive systems are considered. Simulation results confirm that the proposed estimators provide better performance than the classical correlation approach and the conventional MUSIC algorithm for separating closely spaced signals with narrowband spectra. 相似文献
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Prashanth Hande Lang Tong Ananthram Swami 《The Journal of VLSI Signal Processing》2002,30(1-3):163-178
The multipath delay estimation problem for a slow frequency hopping system is studied. High resolution delay estimation algorithms are proposed by exploiting invariance structures in the data packet. The proposed approach converts the problem of delay estimation using temporally received packets to one of estimating directions-of-arrival in array processing. Two closed-form estimators are developed. The first algorithm is based on the use of a single invariance and applies the ESPRIT algorithm. The second approach utilizes multiple invariances, and enforces the Cayley-Hamilton constraint in the signal subspace. It is shown, via an analysis of acquisition time, that the use of multiple invariances significantly shortens the number of hops required for parameter identifiability. Simulation examples also demonstrate the advantage of exploiting multiple invariances. 相似文献
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Kwon Soonho Kim Daeoh Lee Jihye Moon Sangmi Chu Myeonghun Bae Sara You Cheolwoo Liu Huaping Kim Jeong-Ho Kim Dae Jin Park Hosung Kim Jin Young Kim Cheol-Sung Hwang Intae 《Wireless Personal Communications》2018,103(2):1443-1464
Wireless Personal Communications - In general, a ground telemetry station for a launch vehicle (LV) includes a tracking function only; therefore, position measurements for LV depend on received... 相似文献
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研究多径传输条件下的时延估计问题。利用三阶累积量的一维切片作为高阶统计量,结合相关算法原理,提出一种新的时延估计算法。为提高时延估计精度,对相关数据进行了加权处理。该算法可有效抑制空间相关高斯噪声或对称分布噪声,得到非高斯信号准确的时延估计。算法具有计算量小,易于实现的优点。仿真结果表明了该算法的有效性。 相似文献
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现代雷达信号环境中, 复合调制信号正在逐步得到广泛应用。该文提出了一种针对频移键控与二相编码(FSK-BPSK)复合调制信号的时差估计算法。该算法紧密结合该信号子脉冲频率分布具有对称性, 时域长度具有一致性等特点, 通过子脉冲相关函数的理论推导得出FSK-BPSK复合调制脉冲信号的相关函数。最后利用相关函数拟合算法, 可根据观测数据进一步精确估计时间延迟(TDOA)。通过仿真实验, 证明该算法相比于其他时差估计算法, 其算法估计的准确性、抗噪性都有明显提升, 且适用于带宽较小的复合调制信号的时差估计情况。 相似文献
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一种在非视距环境中的TDOA/AOA混合定位方法 总被引:2,自引:0,他引:2
提出了一种在非视距环境中的到达时间差/到达角混合定位方法。该方法使用了两步卡尔曼滤波。先用卡尔曼滤波器对到达时间测量值进行预处理,以消除TOA测量值中的NLOS误差。再把经过预处理的TOA测量值输入到用卡尔曼滤波器实现的TDOA/AOA混合定位器中进行定位。实验证明,该方法的定位误差性能优于单纯的TDOA定位方法及静态定位方法中泰勒级数展开法的误差性能。 相似文献
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一种TDOA/AOA混合定位算法及其性能分析 总被引:22,自引:5,他引:17
在蜂窝移动通信系统中,智能天线阵列的应用使得服务基站(BS)能提供较准确的移动台(MS)电波到达角(AOA)测量值,从而可以用于对移动台的定位估计,文中对文献[1]的电波到达时间差(TDOA)定位算法进行了改进,提出了一种既能继承原算法的优良性能,又可充分利用AOA测量值信息提高定位性能的TDOA/AOA混合定位算法,该算法还具有解析表达式解。仿真结果表明,只要AOA测量值达到一定精度,该算法就能取得比文献[1]的单纯TDOA定位算法更好的性能。 相似文献