The effect of error in position co-ordinates of the receiving antenna on the single-satellite-mode GPS timing

It is well established that the position co-ordinates of the receiving antenna should be determined precisely in advance for getting Time of the GPS receiver through a single GPS satellite technique. So it is desirable to know the extent of accuracy of the position co-ordinate required for a particular timing accuracy. In this paper, an analytical expression relating to the position error and the corresponding error in the Time of the GPS receiver has been derived. Time error of the GPS receiver caused by the error in position coordinates largely depends on the position of the satellite indicated by the respective elevation and azimuth of the satellite. To validate the derived formulation it is important to configure the experimental plan very judiciously. A special experiment has accordingly been conducted at National Physical Laboratory, New Delhi, India (NPLI). The observed data have been found to tally well with the derived relation.