Study of Ionospheric Scintillation at Low Latitude GPS Stations And Ephemeris Threat Models

  ijett-book-cover  International Journal of Engineering Trends and Technology (IJETT)          
  
© 2013 by IJETT Journal
Volume-4 Issue-4                       
Year of Publication : 2013
Authors : M.Venkatesh Chowdary , M.Anilkumar

Citation 

M.Venkatesh Chowdary , M.Anilkumar. "Study of Ionospheric Scintillation at Low Latitude GPS Stations And Ephemeris Threat Models". International Journal of Engineering Trends and Technology (IJETT). V4(4):913-916 Apr 2013. ISSN:2231-5381. www.ijettjournal.org. published by seventh sense research group.

Abstract

Global positioning system (GPS) is a satellite based navigation system , which is developed by the Department of Defense (DOD) USA. GPS provides 3D position, velocity and time in all weather conditions. GPS position accuracy is limited by several error sources such as satellite ephermies, multipath effect, clock inaccuracies errors, ionospheric&tropospheric errors and relativistic errors. Among them the ionospheric error is the predominant one. Ionosphere scintillations can be limiting the GPS positional accuracy. Ionospheric scintillation is low frequency, random perturbations of the amplitude and/or phase of the carrier and code signals caused by very small irregularity structures in the ionosphere. In this paper, ionospheric scintillations are analyzed . For this purpose, data of dual frequency GPS receiver located in Hyderabad, Bangalore, Bhopal are considered. The preliminary results would be useful for developing now/forecasting ionospheric scintillation model over low latitude region and also Ephemer is treat models

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Keywords
GPS, Ionospheric Scintillations and TEC.