Onroad GPS Availability Analysis

This paper presents an analysis of Global Positioning System (GPS) availability from the perspective of dilution of precision (DOP) and number of satellites in view. GPS data used in the analysis were taken from a 13,000 km U.S. test vehicle drive comprising a real world driving profile of freeways, rural, urban, and residential roads. Metrics examined are: DOP outage period duration, distribution of DOP values, and the distribution of the number of satellites available for positioning.