Download PDFOpen PDF in browserStudy of GPS Positional Error Near the Crest of the Equatorial Ionization Anomaly during Quite DayEasyChair Preprint 37278 pages•Date: July 3, 2020AbstractThe accuracy with which a user receiver can determine its position or velocity, or synchronize to GPS system time, depends on a complicated interaction of various factors. In general, GPS accuracy performance depends on the quality of the pseudorange measurements as well as the satellite ephemeris data. The accuracy to which the satellite clock offsets relative to GPS system time are known to the user, or the accuracy to which satellite-to-user propagation errors are compensated, are important. Relevant errors are induced by the control, space and user segments. To analyze the effect of errors on accuracy, a fundamental assumption is that the error sources can be allocated to individual satellite pseudorange values. The GPS Ionospheric Scintillation and TEC Monitor (GISTM) based GPS receiver was installed at an equatorial station, Bhopal (23.2° N, 77.4° E, Geomagnetic latitude 14.23˚ N), India in order to study GPS position error. The horizontal error, level of confidence in terms of DRMS & CEP, positional error were analyzed from fixed GPS point for 15 August 2005(Quite day). In the present paper an attempt has been made to study the GPS position errors during the quite day, the latitudinal error and longitudinal error in meter were also studied. We observed that the latitudinal error lies between 1.52 to -1.25 meter while in longitudinal error points lies between 1.97 to -1.25 meter. It was observed that most of the error points lie with in the 95% error ellipse. Due to the sufficient number of locked satellites, and in the absence of any ionospheric disturbance, the DOP parameters remained smooth for the whole day, this helps locate precise position. Keyphrases: Circular error probable (CEP), Dilution of Precision (DOP), Global Positioning System (GPS), error-point, ionospheric disturbance, positional error
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