高脉冲重复频率雷达混合滤波解距离模糊方法

Range ambiguity resolving of HPRF radar based on hybrid filter

针对高脉冲重复雷达距离模糊问题,提出一种新的混合滤波解距离模糊方法.通过把脉冲间隔数和脉冲间隔变化量作为目标待估计状态,对离散的脉冲间隔数、间隔变化量和连续的目标状态(位置和速度)进行混合滤波,从而将解距离模糊问题转换为对脉冲间隔数的估计问题.初始时刻,由于距离量测模糊,利用多个高脉冲重复频率(HPRF)采用欧氏距离对混合状态进行初始化.在滤波过程中,为了避免门限选择,首先根据脉冲间隔变化量的有限个离散取值,将六维向量的混合滤波模型等效为有限个五维向量的混合滤波模型;然后对量测分别进行混合滤波;最后通过对各模型得到的新息的2范数进行比较获得混合状态估计,从而实现解距离模糊.混合滤波解距离模糊方法为实现高脉冲重复频率雷达实时解距离模糊提供了一种新的研究思路,仿真结果表明,本文提出的混合滤波方法在只有一个脉冲重复频率获得目标量测时较现有多假设方法收敛速度快,并且可以克服多假设方法在脉冲间隔数变化时发生的解模糊错误.

In this paper,a novel method of range ambiguity resolving based on hybrid filter is proposed for highpulse repetition frequency（HPRF） radars.By considering the discrete-valued pulse interval number（PIN） which is described as the radial range of the target divided by the maximum unambiguous range for a certain HPRF and its incremental variable as target states,the problem of range ambiguity resolving is converted to the hybrid state estimation problem.In the initial time steps,since the range measurement is ambiguous,the hybrid state initialization is achieved by utilizing multiple HPRFs based on Euclidean distance.Then,to avoid the choice of the thresholds,the hybrid model based on six-dimension state vector is made equivalent to several hybrid models based on five-dimension state vector according to the values that PIN incremental variable may take.The hybrid estimation is achieved by comparing 2-norm of the innovations obtained from several hybrid filters.Simulation results demonstrate that the proposed method can converge more rapidly than the existing multiple hypothesis method when only one HPRF has target measurement and overcome the mistake that multiple hypothesis method makes when PIN varies.