摘要
利用全球降水测量(Global Precipitation Measurement,GPM)卫星上搭载的微波成像仪(GPM Microwave Imager,GMI)的一级亮温数据,通过谱差法识别被无线电频率干扰(radio frequency interference,RFI)污染的典型陆地地区,确定欧洲、东亚和南美作为主要研究区域,进一步分析RFI与卫星方位角、太阳方位角和太阳天顶角之间的关系,讨论RFI的影响因子。结果表明:水平极化方式下受RFI影响的区域范围比垂直极化方式下的范围更广;相对于强RFI信号分布对应的较宽的卫星方位角区间,存在RFI的像素点对应的太阳方位角和太阳天顶角角度区间范围较为集中;当RFI强度较弱时,垂直极化方式下的RFI的像素点远多于水平极化方式下的RFI像素点,但随着RFI强度的增强,水平极化方式下的RFI像素点多于垂直极化方式下的RFI像素点,且强度越大则两种极化方式下的RFI像素点数量差距越大。
Using the level-1 brightness temperature data from the Global Precipitation Measurement(GPM)Microwave Imager(GMI),the typical continental areas contaminated by radio frequency interference(RFI)are identified by spectral difference method,and Europe,East Asia,and South America are selected as the main research areas.Furthermore,the relationship between RFI and satellite azimuth,solar azimuth,and solar zenith angle is analyzed to discuss the impact factors of RFI.The results are shown as follows.The area affected by RFI is wider in horizontal polarization mode than in vertical polarization mode.Compared with the wide range of satellite azimuth corresponding to the strong RFI signal distribution,the angular range of solar azimuth and solar zenith angle corresponding to RFI pixels is more concentrated.When the intensity of RFI is weak,the number of RFI pixels in vertical polarization mode is far more than that in horizontal polarization mode.However,as the intensity of RFI increases,the number of RFI pixels in horizontal polarization mode is more than that in vertical polarization mode,and the greater the intensity,the greater the difference between the number of RFI pixels in the two polarization modes.
作者
张玉璇
吴莹
ZHANG Yuxuan;WU Ying(Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration,Nanjing University of Information Science&Technology,Nanjing 210044,China;College of Ocean and Meteorology,Guangdong Ocean University,Zhanjiang 524088,China;School of Atmospheric Physics,Nanjing University of Information Science&Technology,Nanjing 210044,China)
出处
《海洋气象学报》
2022年第3期99-108,共10页
Journal of Marine Meteorology
基金
国家自然科学基金项目(41975046,41305033)。
关键词
微波成像仪(GMI)
亮温
无线电频率干扰
影响因子
GPM Microwave Imager(GMI)
brightness temperature
radio frequency interference(RFI)
impact factor