Performance assessment of a noniterative algorithm for Global Positioning System (GPS) absolute positioning

The Global Positioning System (GPS) is a constellation of 24 navigation satellites developed and deployed by the U.S. Department of Defense to provide worldwide real-time positioning capability to its military and civilian users. Generally. GPS absolute positioning solutions are computed by using an iterative procedure that requires an initial approximate value for the receiver's position. This paper evaluates a direct, noniterative algorithm for computation of the position and clock error of a single GPS receiver. An exact solution is obtained with four GPS satellites in view. The algorithm automatically combines all available GPS pseudorange measurements when more than four satellites are observed. Experimental results show that reliable absolute positioning is achieved by using the algorithm, and that the computational effieciency is improved by a factor of 2.3 over the traditional iterative method.