地基GPS与掩星联合的电离层层析成像方法研究

Computerized Ionospheric Tomography Combining with Ground-based GPS and Radio Occultation

由于有限视角、稀疏布站等原因,地基GPS电离层层析成像存在垂直分辨率不高的问题,联合掩星进行电离层层析成像是一个重要的解决途径。一方面地基GPS观测能保证电离层层析成像的时间连续性和区域覆盖性;另一方面由于掩星信号能够提供地基GPS没有的水平射线信息,提升了电离层层析成像的垂直分辨率水平。利用地基GPS站与COSMIC卫星的掩星观测进行的仿真结果表明:与仅利用地基GPS相比,联合掩星进行电离层层析成像,不仅在电离层电子密度反演精度方面有明显提升,而且在电离层F2层峰值高度(hmF2)和电离层总电子含量(TEC)的精度方面同样有明显提高。

Due to the limited-angle geometry and sparse receiver of the ground-based GPS observations ,computerized ionospheric tomography （CIT） with ground-based GPS will leads to lower vertical resolution of the electron density ,combining radio occultation obser-vations is able to solve this problem .As one side ,ground-based GPS can ensure the tempo-ral continuity and spatial coverage of the CIT ,the other side ,horizontal radio occultation da-ta provide the ray information that is not available from angle-limited ground-based GPS , which will improve the vertical resolution of the CIT .Gound-base GPS stations and radio oc-cultation from COSMIC satellites were selected for CIT simulation .Comparison between on-ly ground-based GPS CIT and combined method show that the combined method not only has higher precision in electron density but also in ionospheric F2 layer peak height （hm F2 ） and total electron content （TEC） .