星载多普勒雷达云中大气风场测量仿真研究  

Study and Simulation on Measurement of Atmospheric Wind Field in Cloud by Spaceborne Doppler Radar

作　　者：刘顺飞 朱迪 董晓龙 LIU Shunfei;ZHU Di;DONG Xiaolong(National Space Science Center,Chinese Academy of Sciences,Beijing 101400,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院国家空间科学中心,北京101400 [2]中国科学院大学,北京100049

出　　处：《遥感技术与应用》2023年第4期903-912,共10页Remote Sensing Technology and Application

基　　金：空间科学预先研究项目“星载毫米波云雷达多普勒信号探测技术研究”(XDA15018600);空间科学预先研究项目“星载毫米波云雷达多普勒信号探测技术研究”(XDA15018600)。

摘　　要：全球风廓线的测量对提高数值天气预报精度,准确描述气候模型,理解大气中的物理过程具有重要意义。云雨条件下,星载大气风场多普勒速度测量能力依赖于雷达系统参数、云的物理和动力特征及测量方法。基于极化分集脉冲对(Polarization Diversity Pulse-Pair,PDPP)算法,研究了脉冲时序和多普勒速度测量精度的关系。对影响PDPP方法多普勒测量精度的因素进行了仿真分析。结果表明,对W波段雷达,脉冲对重复频率应当在3.5~5 KHz范围。使用0.1°波束宽度的天线在脉冲间隔为30~50 us区间内,能对反射率因子-20 dBZ的云内风速进行测量,精度在1.35 m/s;相同精度要求下,0.2°波束宽度的天线在脉冲间隔为30~40 us范围内,能达到探测灵敏度约-12 dBZ。Global wind profile plays a critical role in improving accuracy of numerical weather prediction,accu⁃rately describing climate models and understanding the atmospheric physical processes.Under cloud and rain conditions,the Doppler velocity measurement ability of spaceborne atmospheric wind field is highly dependent on radar system parameters,the physical and dynamic characteristics of cloud and measurement method.Based on Polarization Diversity Pulse Pair(PDPP)algorithm,the relationship between pulse timing and Doppler ve⁃locity measurement accuracy is studied.The factors affecting the Doppler measurement accuracy of PDPP meth⁃od are simulated and analyzed.The results show that for W-band radar,the pulse pair repetition frequency should be in the range of 3.5~5 kHz.The antenna with 0.1°beam width can measure the in-cloud wind speed with reflectivity factor of about-20dBz in the pulse interval of 30~50μs,and the accuracy is 1.35 m/s;Under the same accuracy requirements,the antenna with 0.2°beam width can achieve detection sensitivity of about-12 dBz in the range of pulse interval of 30~40μs.

关 键 词：云内大气风场 极化分集脉冲对算法 PRF设计 多普勒测量 

分 类 号：P415.2[天文地球—大气科学及气象学]