Analysis of GPS Receiver Performance by the GPS Satellite Clock Anomaly

Abstract

The importance of the Global Position System (GPS) is becoming larger and larger since it is one of the Global Navigation Satellite Systems (GNSS) and is regarded as a national infrastructure in the field of position and timing. Application areas of the GPS include military, surveying, geodesy, car navigation, marine system, aircraft system and network synchronization. In recent year, the application area expands into natural science applications, architecture, communication, weather forecasting, and LBS (Location Based Service). Dependency of the GPS will be rapidly increasing as the application area grows. GNSS fault can give a large impact on social security system as well as economic system. In the marine and aircraft related areas which require strict safety conditions, the reliability of the GNSS is much more important since a fault of the GNSS may give rise to a fatal accident. Study on the GPS integrity monitoring is being actively carried out by many researchers as the GPS takes an important position in social infra structure. Also GPS satellite failure effects on all GPS receivers and it is not easy to recovery failed GPS satellite in the fast time. GPS satellite failures classify into signal generator failure, satellite clock failure, and signal spectrum failure. Especially, GPS satellite clock failure has effect on all of the GPS signal generator part. This paper analyzes effect on performance of GPS receiver due to GPS satellite clock failure. First of all, it analyzes effect on correlator in GPS receiver due to signals generated from GPS satellite clock fault through simulation. And to evaluate effect on navigation performance, it measures pseudorange and pseudorange rate using GPS simulator. This paper shows a detection probability of a GPS satellite clock failure using the conventional signal quality monitoring (SQM) method through this analysis.