Assessment of vertical TEC mapping functions for space-based GNSS observations

The mapping function is commonly used to convert slant to vertical total electron content (TEC) based on the assumption that the ionospheric electrons concentrate in a layer. The height of the layer is called ionospheric effective height (IEH) or shell height. The mapping function and IEH are generally well understood for ground-based global navigation satellite system (GNSS) observations, but they are rarely studied for the low earth orbit (LEO) satellite-based TEC conversion. This study is to examine the applicability of three mapping functions for LEO-based GNSS observations. Two IEH calculating methods, namely the centroid method based on the definition of the centroid and the integral method based on one half of the total integral, are discussed. It is found that the IEHs increase linearly with the orbit altitudes ranging from 400 to 1400 km. Model simulations are used to compare the vertical TEC converted by these mapping functions and the vertical TEC directly calculated by the model. Our results illustrate that the F&K (Foelsche and Kirchengast) geometric mapping function together with the IEH from the centroid method is more suitable for the LEO-based TEC conversion, though the thin layer model along with the IEH of the integral method is more appropriate for the ground-based vertical TEC retrieval.

[1]  Gottfried Kirchengast,et al.  A simple “geometric” mapping function for the hydrostatic delay at radio frequencies and assessment of its performance , 2002 .

[2]  D. Bilitza,et al.  International Reference Ionosphere 2007: Improvements and new parameters , 2008 .

[3]  Jong-Uk Park,et al.  Long‐term analysis of ionospheric polar patches based on CHAMP TEC data , 2013 .

[4]  K. Davies,et al.  Studying the ionosphere with the Global Positioning System , 1997 .

[5]  J. Klobuchar Ionospheric Time-Delay Algorithm for Single-Frequency GPS Users , 1987, IEEE Transactions on Aerospace and Electronic Systems.

[6]  T. Gulyaeva,et al.  Comparison of two IRI electron-density plasmasphere extensions with GPS-TEC observations , 2007 .

[7]  Paul D. Craven,et al.  Global Core Plasma Model , 2000 .

[8]  S. Syndergaard A new algorithm for retrieving GPS radio occultation total electron content , 2002 .

[9]  K. Larson,et al.  Routine determination of the plasmapause based on COSMIC GPS total electron content observations of the midlatitude trough , 2010 .

[10]  Hyun-Yup Lee,et al.  Characteristics of global plasmaspheric TEC in comparison with the ionosphere simultaneously observed by Jason‐1 satellite , 2013 .

[11]  J. Klobuchar Ionospheric Effects on GPS , 2009 .

[12]  Stefan Heise,et al.  Sounding of the topside ionosphere/plasmasphere based on GPS measurements from CHAMP: Initial results , 2002 .

[13]  J. Forbes,et al.  Longitudinal and geomagnetic activity modulation of the equatorial thermosphere anomaly , 2010 .

[14]  Oliver Montenbruck,et al.  Ionospheric Correction for GPS Tracking of LEO Satellites , 2002, Journal of Navigation.

[15]  A. Komjathy,et al.  Dayside global ionospheric response to the major interplanetary events of October 29–30, 2003 “Halloween Storms” , 2005 .

[16]  Gabor E. Lanyi,et al.  A comparison of mapped and measured total ionospheric electron content using global positioning system and beacon satellite observations , 1988 .

[17]  D. L. Carpenter Whistler evidence of the dynamic behavior of the duskside bulge in the plasmasphere , 1970 .

[18]  A. Rius,et al.  Estimation of the transmitter and receiver differential biases and the ionospheric total electron content from Global Positioning System observations , 1994 .

[19]  Xinan Yue,et al.  Quantitative evaluation of the low Earth orbit satellite based slant total electron content determination , 2011 .

[20]  M. J. Birch,et al.  On the use of an effective ionospheric height in electron content measurement by GPS reception , 2002 .

[21]  Dieter Bilitza,et al.  International reference ionosphere , 1978 .

[22]  A. Garcia-Rigo,et al.  The IGS VTEC maps: a reliable source of ionospheric information since 1998 , 2009 .

[23]  Z. Huang,et al.  Analysis and Improvement of Ionospheric Thin Shell Model Used in SBAS for China Region , 2013 .

[24]  Ding Feng,et al.  Experimental observation and statistical analysis of the vertical TEC mapping function , 2010 .

[25]  Attila Komjathy,et al.  Space Weather and the Global Positioning System , 2008 .

[26]  Anthony J. Mannucci,et al.  A global mapping technique for GPS‐derived ionospheric total electron content measurements , 1998 .

[27]  E. Astafyeva Dayside ionospheric uplift during strong geomagnetic storms as detected by the CHAMP, SAC-C, TOPEX and Jason-1 satellites , 2009 .

[28]  Geoffrey Blewitt,et al.  An Automatic Editing Algorithm for GPS data , 1990 .

[29]  X. Dou,et al.  New aspects of the ionospheric response to the October 2003 superstorms from multiple‐satellite observations , 2014 .

[30]  Xingliang Huo,et al.  Monitoring the Daytime Variations of Equatorial Ionospheric Anomaly Using IONEX Data and CHAMP GPS Data , 2011, IEEE Transactions on Geoscience and Remote Sensing.

[31]  Mark B. Moldwin,et al.  Global plasmaspheric TEC and its relative contribution to GPS TEC , 2008 .

[32]  Pau Bergadà,et al.  A comprehensive sounding of the ionospheric HF radio link from Antarctica to Spain , 2013 .

[33]  M. Grassi,et al.  Geometric total electron content models for topside ionospheric sounding , 2014, 2014 IEEE Workshop on Environmental, Energy, and Structural Monitoring Systems Proceedings.

[34]  M. Fox,et al.  A simple, convenient formalism for electron density profiles , 1994 .