There are two main problems in bearing-only tracking: system's nonlinearity and inscrutability of the range of target.

被动式目标跟踪主要存在两个问题：系统非线性和距离不可观测性。

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Tracking target by using anti-helicopter mine (AHM) is actually the bearing-only measurement because precision of range detected by passive acoustic measurement cant satisfy the need of tracking.

目前被动声探测距离精度还不能满足跟踪的需要，因此，反直升机智能雷对目标的跟踪问题归结为仅有角测量的跟踪问题。

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In this paper, a new bearings only tracking approach, which consists of a set of weighted least squares filters (LSF) each with a different initial range estimate, is proposed.

提出了一种利用基于距离参数的最小二乘滤波器群的纯方位跟踪目标参数估计器，该估计器是由若干个处地不同的距离区间上的加权最小二乘滤波器组成。

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