Abstract：Cosidrering the actuality of GPS pseudorange point positioning with bad height accuracy, a new approach named as mirror surface symmetry method is proposed. It takes the tangent plane through the approximate coordinate of the station on the ellipsoid as the symmetry plane. The real observable satellites make the virtual satellites by symmetry, the pseudorange observation values of the real observable satellites are used to constitute the virtual observation values. The new approach, using the real observation values, virtual observation values for point positioning, can not only increase the number of satellites used to position but also improve the geometric structure in the GPS height direction in theory. The computation results of the experiment computations indicate that the effect of the new method obviously excel that of the existing method in the accuracy of the point positioning, especially the GPS height accuracy.
