C^2动态相位估计的偏差补偿算法--雷达低空目标俯仰角测量提取的研究与应用

Bias compensation algorithm of C^2 dynamic phase estimate——Radar Low-Altitude Target Elevation Off-axis Tracking and Measurement

由于多径回波信号的干扰,极大地影响了雷达对低空目标俯仰角的测量,且对低空目标俯仰角的闭环跟踪测量实现极为困难,通常采用偏轴跟踪技术。通过对多路径反射环境模型分析,同时考虑镜面反射和漫反射的干扰,得出了岸、海基单脉冲雷达低空目标跟踪时俯仰角测量误差的产生原因,将传统的多目标分辨算法(C^2算法)与偏差补偿技术相结合应用于低角多径环境下偏轴跟踪目标俯仰角的测量,由C^2算法代替偏差补偿算法的航迹滤波并且动态估计直射和反射路径的相位差,然后对单脉冲比进行补偿,弥补两种算法各自的不足。在给定的测量环境下对不同高度目标进行了仿真,得到良好的仿真结果,表明C^2动态相位估计的偏差补偿算法,可较大地提高低空目标偏轴跟踪俯仰角的测量精度。并将其应用于某次试验中对掠海巡航飞行目标俯仰角的事后提取,与雷达实时输出的俯仰角测量数据相对比,验证了该算法的有效性和可实施性。

In the presence of sea-surface multi-path mono-pulse radar measure a low elevation target is difficulty. So we adopt off-axis tracking technique generally. By means of the analysis based on the model of multi-path reflection environment, both specular reflection and diffuse reflection are considered. Expression for the average bias in the mono-pulse ratio due to specular and diffuse reflections and the noise in the radar channel are derived. C^2 algorithm combine with bias compensation to adapts for measurement extraction the elevation in presence of sea-surface multi-path,which can improve the disadvantage of all both technique. Using C^2 algorithm substitutes tracking filter of bias compensation and estimates the phase difference between direct and reflections due to path length difference. Throughout the simulation in some scenarios shows combine with two algorithms is effective for off-axis tracking the target in low-altitude and multi-path environment. The results of simulation indicate it can improve the precision of low-altitude target elevation measurement in off-axis tracking radar system. Then give the real time data of elevation measurement by actual radar system and off-line measurement extraction data by bias compensation algorithm of C^2 dynamic phase estimate in one trial. The result indicates this method is effective and feasible in the off-line elevation extraction and it can remarkably improve the precision of elevation measurement.