In this Letter, considering the configuration of small antenna array aperture used for special usage, the authors proposed a target trajectory estimation method by unambiguous phase differences with prior knowledge on target velocity from a single fixed passive sensor. First, they developed the maximum likelihood estimator of the target trajectory parameters based on unambiguous phase differences and then deduce the corresponding Cramer–Rao lower bound. Furthermore, in terms of the error in prior knowledge on target velocity, the influence of target velocity mismatch on trajectory parameters estimation is analysed. Finally, they evaluated the performance of the proposed method and validated the correctness of their analysis via numerical simulation.

中文翻译：

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通过单个固定无源传感器的明确相位差估算目标轨迹

在这封信中，考虑到用于特殊用途的小天线阵列孔径的配置，作者提出了一种具有明确相位差的目标轨迹估计方法，并且具有来自单个固定无源传感器的目标速度的先验知识。首先，他们根据明确的相位差开发了目标轨迹参数的最大似然估计，然后推导了相应的Cramer-Rao下界。此外，针对先验知识对目标速度的误差，分析了目标速度失配对轨迹参数估计的影响。最后，他们评估了所提方法的性能，并通过数值模拟验证了其分析的正确性。