天线罩疏水层老化对微波辐射计观测的影响分析  

Influence Analysis of Hydrophobic Layer Aging of Radome on Microwave Radiometer Observation

作　　者：茆佳佳[1] 焦志敏 张雪芬[1] 王志诚 王志成[1] 马强 周铁桩 MAO Jiajia;JIAO Zhimin;ZHANG Xuefen;WANG Zhicheng;WANG Zhicheng;MA Qiang;ZHOU Tiezhuang(CMA Meteorological Observation Center,Beijing 10oo81;Zhejiang Atmospheric Detection Technology Support Center,Hangzhou 310018;Inner Mongolia Ulanqab Meteorological Bureau,Ulanqab 012000;Hailar District Meteorological Bureau,Inner Mongolia,Hulunbuir 021008)

机构地区：[1]中国气象局气象探测中心,北京100081 [2]浙江省大气探测技术保障中心,杭州310018 [3]内蒙古乌兰察布市气象局,乌兰察布012000 [4]内蒙古自治区呼伦贝尔市海拉尔区气象局,海拉尔021008

出　　处：《气象科技》2022年第6期759-765,共7页Meteorological Science and Technology

基　　金：国家重点研发计划“超大城市垂直综合气象观测技术研究及试验”(2017YFC1501700)资助。

摘　　要：地基微波辐射计因天线罩疏水层老化,在雨天探测时天线罩上易形成积水从而造成探测性能的不稳定,是影响其在科研业务中广泛应用的关键问题之一。本研究利用2017—2018年北京地区6台微波辐射计降雨期间的观测数据,分析天线罩疏水层老化对其观测亮温的影响,结果显示随着天线罩使用时间的增长,尤其是使用3个月以后,降水时亮温增大的幅度明显变大,降水结束后亮温增大的持续时间也有增长趋势。同时,在北京南郊站开展的微波辐射计天线罩淋雨试验结果表明,天线罩使用40 d以后,随着天线罩污染老化,淋雨时观测亮温增大的幅度呈跳跃式增长,且淋雨结束后亮温仍然偏高,最长时间达2 h以上。因此,为提高微波辐射计观测数据的可用性,建议在实际使用过程中每季度更换一次天线罩,对于京津冀等重污染地区可根据实际情况适当提高更换频次。Due to the ageing of the hydrophobic layer of the radome,the ground-based microwave radiometer is prone to form water accumulation on the radome during rainy weather detection,resulting in unstable detection performance,which is one of the key problems affecting its wide application in scientific research and business.This study uses the actual observation data of 6 microwave radiometers in Beijing during the rainfall period from 2017 to 2018.It analyzes the influence of the ageing of the hydrophobic layer of the radome on the observed brightness temperature of the microwave radiometer.The results show that increasing with the use time,especially after three months,the magnitude of the increase in the brightness temperature during precipitation becomes significantly larger,and the duration of the increase in the brightness temperature after the precipitation also increases.At the same time,the rain test of the radome is carried out using the microwave radiometer in Beijing Nanjiao Station.The results show that after the radome is used for 40 days,with the pollution and ageing of the radome,the observed brightness temperature increases in a jumping manner during rain,and the brightness temperature is still high after the rain,even after more than 2 hours.Therefore,in order to improve the availability of microwave radiometer observation data,it is recommended to replace the radome every quarter during actual use.For heavily polluted areas such as Beijing,Tianjin and Hebei,the replacement frequency can be appropriately increased according to the actual situation.

关 键 词：微波辐射计 天线罩 亮温 雨天 

分 类 号：P412[天文地球—大气科学及气象学]