In this letter, a three-dimensional (3D) joint estimation algorithm which is the variable-step hill-climbing algorithm based on two-step weighted least squares (VHC-2WLS) is proposed. The VHC-2WLS combines bistatic range (BR), time difference of arrival (TDOA) and Doppler shift (DS) to improve the estimation accuracy of the position and velocity of a moving target in the multistatic radar system (MRS). First, the position of a moving target is estimated by utilizing two-step weighted least squares (2WLS) method. Second, the estimated position from the first step is optimized by variable-step hill-climbing (VHC) method. Finally, the velocity is calculated through the optimized position value from the second step and least squares (LS) approach. The proposed method is corroborated by simulations to be able to reach the Cramer-Rao lower bound (CRLB) accuracy under mild noise conditions. Numerical simulations demonstrate the superiority in the estimation accuracy of the proposed algorithm over state-of-the-art methods.

中文翻译：

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VHC-2WLS算法对多基地雷达系统中运动目标位置和速度的3D联合估计


在这封信中，提出了一种三维（3D）联合估计算法，即基于两步加权最小二乘（VHC-2WLS）的变步长爬山算法。 VHC-2WLS结合了双基地测距（BR）、到达时间差（TDOA）和多普勒频移（DS），以提高多基地雷达系统（MRS）中运动目标位置和速度的估计精度。首先，利用两步加权最小二乘法（2WLS）估计运动目标的位置。其次，通过变步爬山（VHC）方法优化第一步的估计位置。最后，通过第二步的优化位置值和最小二乘法（LS）计算速度。仿真证实所提出的方法能够在轻度噪声条件下达到 Cramer-Rao 下界（CRLB）精度。数值模拟证明了所提出的算法在估计精度方面优于最先进的方法。