【摘要】 天气雷达的定标直接影响着探测参量的准确度,因此对于雷达数据的应用是至关重要的。利用金属球对X波段固态天气雷达的反射率因子、差分反射率和径向速度同时进行标定。根据待测固态天气雷达的特点,制定了详细的定标实施方案,定标过程中选取远近两个测试点,采用3种不同类型的标准球。试验结果表明:反射率因子理论值和测试值平均相差3dB,标准球的材质对反射率因子的定标影响较小,标准球的直径对定标的有较大的影响;随着采样点数的减少不同类型的标准球对应的反射率因子存在下降的趋势,反射率因子的观测值在采样点数为256、128时分别比采样点数为512时平均降低0.12dB和0.4dB;金属球对应的差分反射率平均值为1.7dB,与理论值存在较大偏差,需要进一步分析原因;雷达观测的径向速度与通过GPS信息的计算值相差小于0.1m/s;金属球对应的反射率因子随方位角、仰角的变化可以反映雷达天线方向性图。试验为双偏振天气雷达定标提供参考。更多还原

【Abstract】 Calibration of weather radar has a direct impact on the accuracy of detection variables and therefore is critical for most applications of radar data.In this paper,we will focus on simultaneous calibration of reflectivity(Z),differential reflectivity(ZDR)and radial velocity(V)for X-band solid-state weather radar.To conducting calibration experiments,detailed calibration implementation plan is formulated,two test points are selected and three kinds of spheres are used.Experiments results show that the theoretically calculated Zthand measured Zm have a mean bias of 3 dB and the bias is more affected by the radius than the material of the spheres.The reflectivity has a downward trend and decreases successively from 0.4 to 0.12 dB along with the decent of sampling number.The mean ZDRis about 1.7 dB,which is large deviation in comparison with the theoretical value.The radial velocity(Ve)calculated from GPS information and observed(Vob)have a difference less than 0.1 m/s.It is also found that the radar reflectivity variation of metal sphere with azimuth and elevation angles can reflect radar antenna pattern.This calibration experiments provides reference for Dual-polarization radar.更多还原