An assisted GPS support for GPS simulators for embedded mobile positioning

Abstract

ABSTRACT During recent years, location technologies have emerged as a research area with many possible applications in wireless communications, surveillance, military equipment, etc. Locati on Based Services (LBS) such as safety applications have become very popular. For example, US Federal Communication Commission Enhanced 911 (E911) Mandate seeks to provide emergency services personnel with location information that will enable them to dispatch assistance to wireless 911 callers much more quickly. Assisted GPS (A-GPS) is an extension of the conventional Global Positioning System (GPS) which increases start-up sensitivity by as much as 25 dB relative to conventional GPS and reduces start times to less than six seconds. In A-GPS assistance data is delivered to the receiver through communication links. This paper addresses the generation of the assistance for GPS simulators for testing A-GPS receivers. The proposed approach is to use IP-based links and location support standards for assistance delivery avoiding network-specific signaling mechanisms so that GPS receiver developers can use th is information for testing A-GPS capabilities using basic GPS simulators. The approach is implemented for the GPS simulator developed by the National Instruments