CSES/FY3C掩星与数字测高仪探测电离层特征参数比较分析  

Comparative analysis of ionospheric characteristic parameters detected by CSES/FY3C occultation and ionosonde

作　　者：胡嘉宇 甘呈坤 辜声峰[1,2] HU Jiayu;GAN Chengkun;GU Shengfeng(GNSS Research Center,Wuhan University,Wuhan 430079,China;Hubei Luojia Laboratory,Wuhan 430079,China)

机构地区：[1]武汉大学卫星导航定位技术研究中心,武汉430079 [2]湖北省珞珈实验室,武汉430079

出　　处：《导航定位学报》2023年第4期120-129,共10页Journal of Navigation and Positioning

摘　　要：为了进一步提高当前风云三号系列卫星(FY3C)以及张衡一号电磁监测试验卫星(CSES)等具备北斗卫星导航系统(BDS)及全球定位系统(GPS)无线电掩星(RO)观测能力的低轨卫星所得电离层峰值参数的反演精度,提出一种以数字测高仪探测数据为参考,采用多种时空匹配窗口对掩星反演结果进行电离层特征参数验证分析的方法:实验结合2018-7-20—2018-8-20共计20551次掩星事件,及6094个数字测高仪观测电子密度廓线数据,从峰值密度、峰值高度及临界频率等多方面对FY3C与CSES卫星掩星观测进行对比分析;同时为避免由于不同观测数据时空不一致引入的差异,分析不同时空匹配窗口对掩星与数字测高仪观测结果比对的影响。结果表明:低轨卫星掩星所得峰值参数与数字测高仪观测资料在不同匹配准则下的比较结果存在差异;当空间(时间)窗口不变时,随着时间(空间)窗口增大,无论是低轨卫星掩星同数字测高仪探测数据的比较,还是低轨卫星自身之间的比较,其电离层峰值参数数据匹配的相关性(一致性)都将下降,进而导致相关系数与拟合精度的减小;在相同的时空匹配窗口中,CSES与FY3C掩星反演出的电离层峰值密度相关性较强,而电离层峰值高度相关性较弱;CSES卫星更适合于低纬地区低高度与中高纬地区低中高度的电离层掩星探测,而FY3C卫星则适合于低纬地区中高高度与中高纬地区高于CSES卫星轨道高度的电离层掩星探测。In order to further improve the retrieval accuracy of ionospheric peak parameters obtained by low-orbit satellites with the observation capability of Beidou navigation satellite system(BDS)and global positioning system(GPS)radio occultation(RO),such as current FY-3 series satellites(FY3C)and Zhang Heng-1 China seismo-electromagnetic satellite(CSES),the paper proposed a method of verifying and analyzing the ionospheric characteristic parameters of the occultation inversion results by using the ionosonde observation electron den sity profile data as a reference with multiple time-space matching windows:through the experiment,20551 occultation events of BDS and GPS occultation receivers of FY3C and CSES satellites,and 6094 ionosonde observation electron density profile data from the ionosonde observation during July 20,2018 to August 20,2018 were combined,and a comparative analysis of the occultation observations of FY3C and CSES satellites was carried out in terms of peak density,peak height,critical frequency and so on;moreover,in order to avoid the time-space inconsistency between different data of occultation events and the ionosonde observation,the impact of different time-space matching windows on the comparison of occultation and ionosonde observation was analyzed.Results showed that there would be differences between the peak parameters obtained from the occultation of low-orbit satellites and the observation data of the ionosonde under different matching criteria;and when the spatial(time)window is unchanged,the correlation(consistency)of ionospheric peak parameter data matching would decrease with the increase of the temporal(space)window,whether comparing the LEO satellite occultation with the ionosonde detection data or comparing the CSES satellite with the FY3C satellite,which could lead to the decrease of the correlation coefficient and fitting accuracy;meanwhile,in the same spatial and temporal matching window,the correlation between the peak ionospheric density of CSES and FY3C occultation inverse pe

关 键 词：无线电掩星 风云三号(FY-3) 张衡一号(Zhang Heng-1)电磁监测试验卫星(CSES) 数字测高仪 电子密度廓线 

分 类 号：P228[天文地球—大地测量学与测量工程]