X波段双偏振雷达反射率的衰减订正

雷达在探测降雨时,回波都有衰减。波长较短的X波段雷达地衰减更严重,所以有必要对其回波进行衰减订正。X波段雷达回波差分传播相移(KDP)比C、S波段的要高1.5~3倍。因此可以合理地考虑利用KDP对X波段雷达回波信号反射率的衰减进行订正。又由于当KDP的值较小时,对回波反射率订正效果受到其他因素影响。所以当KDP值较小时,使用反射率(ZH)自身进行订正。利用成都信息工程学院X波段双偏振天气雷达的探测降雨过程的回波数据,在已经提出的算法的基础上,利用ZH-KDP综合算法进行软件设计,并分析回波反射率在算法处理前后的效果。通过订正处理前后的数据绘制曲线图,定量对比分析订正处理前后的反射率值,订正处理后的值比订正处理前的值有增强,又用相同时刻S波段的回波数据对X波段的订正效果进行验证,二者值的大小相差不多,说明ZH-KDP法对回波反射率的衰减有改善。

Attenuation Correction of Reflectivity Factor for X-Band Dual-Polarization Radar

When the radar detects rainfall,it will attenuation. The attenuation of shorter wavelengthx-band radar is more serious,so it is necessary for us to correct its echo attenuation. The differential propagation phase shift（ KDP） of x-band radar is 1. 5 times or 3 times as large that of c-band or s-band radar. We can use KDP to correct the reflectivity of x-band radar. When the value of the KDP is small,the echo correction effect will be a larger error and we can use reflectance itself to do correction. So the in this paper we use x-band dual polarization weather radar of Chengdu University of Information Technology to detect the echo in the process of rainfall. On the basis of existing algorithms,in this paper we design software,and analyze the reflectivity factor echo effect before and after the correction. We can use the graph to analyze the reflectivity data before and after the correction. Comparing to the reflectivity valueafter correction,the reflectivity value before correction has obvious improvement. Finally,we can use s-band radar data to validate the correction effect of x-band.They are similar. This proved that the correction has improved the data.