基于状态解耦的两坐标外源雷达3D目标跟踪

3D target tracking for duel coordinate passive radar based on state decoupling

考虑利用两部两坐标外源雷达对高度近似恒定的目标进行三维跟踪。结合外源雷达自身的特点,提出了一种将目标高度与水平状态(水平位置、速度等)进行解耦估计的方法,通过两个并行估计器来实现对三维目标的跟踪。在高度估计器中,将目标高度区间划分为多个高度子区间,然后利用量测值递推计算目标在各个高度子区间的权重,最后通过加权融合各个高度子区间的方式估计目标高度;在水平面的状态估计器中,进一步考虑了目标在水平面机动的场景,利用交互式多模型扩展卡尔曼滤波器,并结合目标高度的估计值,更新目标的水平状态。仿真与实验结果显示,利用两部两坐标外源雷达可以实现对高度近似恒定目标的精确三维跟踪,为水平机动的目标提供精度在200 m以内的高度估计,并消除了二维跟踪情况下因未考虑目标高度而引起的误差。

Considering tracking the three-dimensional(3D)trajectory of an aircraft with high-nearly constant altitude by two 2D passive radars.On the basis of the characteristics of passive radars,a method is proposed to decouple and estimate the target altitude and the horizontal state(target position,speed,etc.)to realize 3D tracking through two parallel estimators.As to the altitude estimator,the altitude interval of a target is divided into a number of altitude sub-intervals,then the weight of the target in each altitude sub-interval is calculated recursively based on the measurement values,and finally a weighted summation method for all altitude sub-intervals is used to obtain the target altitude.As to the horizontal state estimator,the maneuverability of the target in the horizontal plane is further considered,and an interactive multiple model extended Kalman filter(IMM-EKF)is used to update the target horizontal state in combination with the target altitude estimation value.Simulation and experimental results show that the two 2D passive radars can achieve accurate 3D tracking for an aircraft with nearly constant altitude,providing an altitude estimation within 200 m accuracy for a horizontally maneuvering target,and eliminate the error caused by the regardless of the target’s altitude in 2D tracking condition.