一种星载降水测量雷达和地基天气雷达的频率修正方法  

A frequency correction algorithm for spaceborne precipitation measurement radar and ground-based weather radar

作　　者：吴琼 仰美霖 陈林[1] 尹红刚 商建 谷松岩[1] WU Qiong;YANG Meilin;CHEN Lin;YIN Honggang;SHANG Jian;GU Songyan(Innovation Center for FengYun Meteorological Satellite(FYSIC),Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites,National Satellite Meteorological Centre(National Centre for Space Weather),China Meteorological Administration,Beijing 100081,China;Institute of Urban Meteorology,China Meteorological Administration,Beijing 100089,China)

机构地区：[1]许健民气象卫星创新中心,中国气象局中国遥感卫星辐射测量和定标重点开放实验室/国家卫星气象中心(国家空间天气监测预警中心),北京100081 [2]北京城市气象研究院,北京100089

出　　处：《气象学报》2023年第2期353-360,共8页Acta Meteorologica Sinica

基　　金：国家自然科学基金项目(41905063、42005109、41905034、42005105)。

摘　　要：通过结合全球降水测量卫星(GPM)反演算法中用到的0℃层亮带模型以及米散射计算,生成了固态、液态以及混合相态3种降水情况下的散射函数查算表;通过与GPM实测数据的对比,验证了查算表的精度,表明散射计算的最大偏差小于0.5 dB。基于该查算表,完成了星载Ku波段雷达到S波段雷达的频率修正。对散射函数的分析表明:Ku波段到S波段的频率修正取决于相态以及谱参数(D_(m))。其中,液态降水的频率修正量以负为主,最大不超过-3 dB。混合相态降水的频率修正量随着0℃层亮带高度的不同差异非常明显。固态降水的频率修正在不存在0℃层亮带时均为正,存在0℃层亮带时则随着温度的变化而显著变化。该方法可用于实现星、地不同波段雷达之间的频率修正,为星载雷达探测精度的一致性检验提供有效支撑。By combining the bright band model used in the GPM retrieval algorithm and Mie scattering calculation,the lookup table of scattering functions is generated for three types of precipitation,i.e.,solid precipitation,liquid precipitation and mixed phase precipitation.The accuracy of the lookup table is verified by comparing with the measured data of GPM.The result shows that the maximum deviation of scattering calculation is less than 0.5 dB.Based on the lookup table,the frequency correction from spaceborne Ku band radar to S-band radar is completed.The analysis of the scattering function shows that the frequency correction from Ku band to S band depends on the phase and spectral parameter D_(m).Among them,the frequency correction of liquid precipitation is mainly negative,and the maximum is not more than−3 dB.The frequency correction of mixed phase precipitation varies significantly with the height of the 0℃bright band.The frequency correction of solid precipitation is positive without a 0℃bright band.When there is a 0℃bright band,it changes significantly with temperature.The method proposed in this paper can be used to realize the frequency correction between satellite and ground radars in different bands,and provide effective support for consistency inspection of detection accuracy of spaceborne radar.

关 键 词：全球降水测量卫星 亮带 米散射 查算表 频率修正 

分 类 号：P412.25[天文地球—大气科学及气象学]