昆虫目标雷达散射截面积特征辅助跟踪算法

害虫迁飞具有规模大、突发性强的特点，会导致病虫害异地大爆发，粮食产量下降，造成重大的经济损失。昆虫雷达是监测迁飞性害虫的一种有效手段。昆虫目标的雷达散射截面积(RCS)较小，回波能量弱，在保证高检测率的同时会带来高虚警率问题，进而导致在目标跟踪的数据关联环节，易受虚假量测的影响出现关联错误。幅度特征辅助跟踪算法利用目标与噪声点迹的幅度差异，可以有效提高目标与噪声的识别度，改善跟踪性能，但是其需要已知目标的RCS起伏模型作为先验信息来计算幅度似然比。因此，该文基于Ku波段高分辨昆虫雷达外场实测昆虫回波数据，分析了昆虫目标的RCS起伏特性，得出Gamma分布可以较好地拟合昆虫目标的RCS统计分布，并将其作为先验信息，推导出Gamma起伏目标在高斯白噪声背景下的幅度似然比。通过在不同信噪比、不同量测噪声及不同起伏模型参数下的仿真结果及性能指标分析，验证了相比于概率数据互联滤波算法(PDAF)算法，目标RCS特征辅助的跟踪算法可以有效提高昆虫目标的跟踪精度。 

RCS Feature-aided Insect Target Tracking Algorithm

Pest migration has the characteristics of large scale and strong suddenness, which will lead to the outbreaks of pests and diseases, the decline of grain yield, and considerable economic losses. Entomological radar is an effective means of monitoring migratory pests. However, the Radar Cross Section (RCS) of an insect target is small, whereas the echo power is weak. High detection probability will result in a high false alarm probability. In the data association step of target tracking, the association error occurs due to the influence of false measurement. By utilizing the amplitude difference between the target and noise, the amplitude information-assisted tracking algorithm can effectively improve the recognition degree toward the target and noise and improve the tracking performance. However, the RCS fluctuation model of the target is needed as prior information to calculate the amplitude likelihood ratio. Therefore, in this paper, the insect RCS fluctuating characteristics are analyzed based on Ku-band entomological radar experiment data. The results show that gamma distribution can fit well the RCS probability distribution of the insect target. On this basis, we derive the amplitude likelihood ratio of the gamma fluctuation target in Gaussian white-noise background. By analyzing the simulation results and performance under different signal-to-noise ratios, measurement noises, and fluctuation model parameters, compared with probabilistic data association filter, the RCS feature-aided tracking algorithm can effectively improve the insect target tracking accuracy.