针对机动目标跟踪的雷达发射波形选择

Radar Transmitted Waveform Selection for Maneuvering Target Tracking

该文首先在交互多模型(Interacting Multiple Model,IMM)算法的框架下,选择常速模型和自适应加速度模型作为状态模型,以应对实际中非合作目标的非机动与机动状态,并将此算法称为自适应IMM算法。然后针对机动目标跟踪时,雷达发射波形的选择需要兼顾测距测速性能与多普勒容忍性的问题,提出将V型调频(V-Linear Frequency Modulated,V-LFM)信号作为发射波形。通过分析多脉冲线性调频信号,V-LFM信号和M序列3种信号对目标距离和速度估计性能的克拉美罗下界(Cramer-Rao Lower Bound,CRLB)与多普勒容忍性表明,V-LFM信号可以在较少多普勒容忍性损失的情况下,有效提升对目标距离和速度的估计精度。仿真结果表明:发射多脉冲V-LFM信号并采用自适应IMM算法,可以明显提高雷达系统的跟踪性能。

Firstly, in the framework of the Interacting Multiple Model（IMM） algorithm the constant-velocity model and the adaptive constant acceleration model are selected as the dynamic models for the un-maneuvering and maneuvering states of the un-cooperative target, which is called the adaptive IMM algorithm. Then since it is necessary to consider the performance of estimating range/velocity and Doppler tolerance for tracking a maneuvering target, the V-Linear Frequency Modulated（V-LFM） signal is selected as the transmitted signal in the radar system. The analysis on the Cramer-Rao Lower Bound（CRLB） for estimating the range/velocity and Doppler tolerance of three signals（LFM, V-LFM and M sequence） shows that the V-LFM waveform can effectively improve the performance of estimating the target range and velocity in the case of a bit loss in the Doppler tolerance. The simulations demonstrate that the tracking performance is apparently improved, when multiple pulses of V-LFM waveform is transmitted and the adaptive IMM algorithm is utilized in the radar system.