Global ionospheric models in three dimensions from GPS measurements: Numerical simulation
Main Article Content
Abstract
A network of globally distributed dual frequency Global Position System (GPS) receivers is used to compute global maps of the vertical total electron content (VTEC) distribution of the ionosphere. A mapping function is used to convert the total electron content along the path of the signal into vertical total electron content, which can be represented by two dimensional Taylor series or spherical functions.
This vertical variation cannot be recovered directly from GPS data measured with ground based receivers. The technique was tested with the launch of the GPS - MET mission on April 3, 1995. Combining the trans-ionospheric measurements from ground based receivers with the data collected in the GPS-MET experiment we attempt to model the electron content based on the global behaviour of the ionosphere. Using least square estimation we determine the unknown coefficients of the electron content model. The results suggest that, even without a global geometrical distribution, the space receiver is useful to model the mean high electron content variation.
Article Details
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
References
BRUNINI, C. and A. KLEUSBERG, 1996. Mapas globalesde retardo ionosférico vertical a partir de observaciones GPS, Actas del IV Congreso Internacional de Ciencias de la Tierra, Santiago, Chile, 5 al 9 de agosto de 1996.
HAKEGARD, O., 1995. A regional ionospheric model for real-time predictions of the total electron content in wide area differential satellite navigation systems. Thesis Dr. Ing. Norwegian Institute of Technology.
HARGREAVES, J. K, 1995. The solar – terrestrial environment, Cambridge Atmospheric and Space Science series 5; particularly Chapter 6 on principles of the ionosphere at middle and low latitudes and Chapter7 and 8 on ionospheric phenomena at low, middle and high latitudes.
KLEUSBERG, A. and P. TEUNISSEN, 1996. GPS of Geodesy, Springer. DOI: https://doi.org/10.1007/BFb0117676
MANNUCCI, A., B. WILSON and C. EDWARDS, 1993. A new method for monitoring the earth’s total electron content using the GPS global network. Proceedings ofthe ION GPS-93, Salt Lake City, Utah, September 22-24.
MEZA, A., C. BRUNINI and A. KLEUSBERG, 1997. Ionospheric maps from terrestrial GPS and LEO satellite measurements. Proceeding of Scientific Assembly of the International Association of Geodesy -IAG-, Brasil.
MEZA, A., C. BRUNINI and A. KLEUSBERG, 1998. Analysis of 2 and 3 dimensional ionospheric models using GPS measurements. Proceeding of the V Congreso Internacional de Ciencias de la Tierra, Chile.
RATCLIFFE, J. A., 1972. Physics of the Upper Atmosphere. Academic Press New York and London.