利用QAR和DEM的机载气象雷达地杂波仿真方法

摘要

地杂波是降低机载气象雷达性能的一个关键因素.利用数字高程模型(Digital elevation model,DEM)精确计算不同地形的电磁散射时,本文提出了将经纬度变化量转换成距离变化量的方法,简化计算,并修正了俯角和擦地角计算.然后根据气象雷达方程建模地杂波,按照WXR-2100的实际参数设置雷达参数,结合快速存取记录器(Quick access recorder,QAR)反演的航班飞行参数,分别高保真地仿真了起飞和巡航两个阶段机载气象雷达不同工作模式下的杂波图,反映了实际的运行情况,最后建立了杂波图数据库.%A key factor degrading the performance of airborne weather radar is clutter.Here,the change amount of latitude and longitude is converted into the distance variation to compute electromagnetic scattering of different terrain using a digital elevation model (DEM).The calculation of depression and grazing angle is fixed.According to the meteorological radar equation,the ground clutter is modeled.Radar parameters are set in accordance with the actual parameters of WXR-2100,while flight parameters by the quick access recorder (QAR).The clutter maps for airborne weather radar in the different operating modes are simulated during take-off and cruise stages.The results can reflect actual operating conditions.Finally,the clutter map database is established.