高频地波雷达飞行目标高度估计

高频地波雷达探测空中目标时缺乏俯仰角度信息，不能直接获取飞行目标高度，目标状态初始值对跟踪精度影响很大。提出一种拟牛顿法与高度参数化迭代扩展卡尔曼滤波(heightparameterized iterated extended Kalman filter，HPIEKF)结合的方法跟踪目标三维信息。首先利用雷达系统过去时刻和当前时刻的观测信息通过拟牛顿法估计目标的飞行高度；其次，用该高度值初始化HPIEKF，对飞行目标进行三维信息跟踪。仿真实验表明，拟牛顿法能够以较小误差估计出目标飞行高度，利用该估计值作为HPIEKF跟踪的初始值，提高了跟踪精度。

Estimation of flight altitude in high frequency surface wave radar

High frequency surface wave radar lacks the ability to make a narrow beam in elevation,it can not estimate the target altitude directly,and the initial state influences the tracking accuracy.A method is proposed to track three dimensional information by adopting height-parameterized iterated extended Kalman filter(HPIEKF) combined with a quasi-Newton method.First,a flight altitude of the aircraft is estimated by the former and the present measurements.Second,HPIEKF is initialized with the altitude to track the three dimensional information.Simulation results demonstrate that the quasi-Newton method can estimate the flight altitude with small variance,the HPIEKF initialized by that altitude improves the accuracy of altitude estimation.