Interim report on the geographic dependency and latitude effects study [GPS system]

The effects of the various Global Positioning System (GPS) system error sources are being investigated for their influence on time dissemination. Data are being gathered from a variety of tracking and timing centers to attempt to identify and quantify the errors and their sources. The known influences of GPS satellite position error, propagation effects, and the ability to maintain time at remote sites are being investigated. Trends in the error propagation of these different effects will be determined, and limits imposed on capability and possible geographic dependency identified. Interim results and tentative conclusions on these efforts are presented