The ultimate objective of the study is to determine a set of algorithms which can be used in a NAVSTAR/GPS user navigation system. The criteria for the acceptability of the algorithm will be the accuracy of the position and velocity determination. Since there is no way of getting real data for algorithm verification at this time, it is imperative to establish system and error models. The results of analysis of proposed algorithms is then relative to the models used. An additional objective of the entire study is that it will be a design aid. Thus it is intended that through analysis of different receiver configurations, an analytic basis for certain design decisions can be established. The final computer program for analysis will not be an interactive computer aided design tool; however, it will provide for inclusion or exclusion of certain receiver options and variability of certain parameters in order to make the analysis useful for making design decisions.