毫米波测云雷达二次回波的回扩识别和距离旁瓣研究  

Back expansion recognition of second-trip echo and range sidelobe research with millimeter wave cloud radar

作　　者：程周杰[1,2] 魏鸣 郎亚军[1] CHENG Zhoujie;WEI Ming;LANG Yajun(Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters,Nanjing University of Information Science&Technology,Nanjing 210044,China;Beijing Institute of Aviation Meteorology,Beijing 100085,China)

机构地区：[1]南京信息工程大学气象灾害预警与评估协同创新中心,南京210044 [2]北京航空气象研究所,北京100085

出　　处：《气象科学》2020年第4期534-539,共6页Journal of the Meteorological Sciences

基　　金：国家自然科学基金资助项目(41675029);国家重点基础研究发展计划973项目(2013CB430102)。

摘　　要：毫米波测云雷达是一种重要的云遥感探测手段。为了获得大功率探测能力,本文所用云雷达使用了脉冲压缩技术和双脉冲技术,但也因此会出现二次假回波和距离旁瓣假回波。本文研究了假回波对云雨探测的负面影响,分析了产生二次回波的原理,设计了区域回扩法结合余弦相似度计算的二次回波定量识别算法。个例分析表明算法有较好的识别能力。本文还为定性判断距离旁瓣影响提供了一种简便可行的途径。研究结果可用于改善毫米波雷达的资料质量。Millimeter-wave cloud radar is an important means of cloud remote sensing.In order to obtain high power detection capability,the radar used in this paper utilizes pulse compression and double-pulse technology which may lead to second-trip and range side lobe fake echoes.In this paper,the negative effects of fake echoes on measurements of cloud/rain are studied.The principle of second-trip echo generation is analyzed,and a secondary echo recognition algorithm is designed based on the combination of area back expansion and cosine similarity calculation.Case studies demonstrate that the algorithm has a strong recognition ability.The paper also provides a simple and feasible way to qualitatively judge the influence of distance side lobe.The results of the study can be used to improve the quality of data in millimeter-wave radars.

关 键 词：毫米波测云雷达 脉冲压缩 双脉冲 二次回波 距离旁瓣 

分 类 号：P415.2[天文地球—大气科学及气象学]