Analysis and estimation of horizontal and vertical components of positioning standard deviation in absolute GPS positioning

The absolute GPS positioning technique, especially precise point positioning (PPP), has been widely applied in a variety of engineering fields. Since the requirements for horizontal and vertical components of positioning standard deviations vary greatly in different applications, it is necessary to study the method of estimating the horizontal and vertical components of positioning standard deviation. In present paper, under the assumption of approximately superseding the Geoid with the WGS-84 ellipsoid surface, the authors analyze the real implications of the horizontal and vertical components of positioning standard deviation in absolute GPS positioning, then derive the estimate formulae for the horizontal and vertical components of positioning standard deviation by using Bursa-Wolf transformation as well as variance-covariance propagation law. Finally, a calculation example is presented.