Pages: 57 to 64
Y. A. Aina, M. M. Hasan, K. Kheder
European Geostationary Navigation Overlay Service (EGNOS) is a Satellite Based Augmentation System (SBAS) being developed by European Space Agency (ESA) to make GPS and GLONASS suitable for civil aviation and other applications. It improves the accuracy of the GPS and GLONASS signals to about 1 to 2 meters. Though corrected signals from EGNOS are receivable in Saudi Arabia, the accuracy of the signals might be degraded due to the far distance between Saudi Arabia and the ground monitoring stations. The precision and availability of the signals are also expected to be reduced. This paper assessed the EGNOS signal receivable in Saudi Arabia by using handheld GPS (Trimble GeoXH 2005) with GPS software (Trimble GPS Controller 2.3 and ArcPad 7). The GPS data was collected in selected Saudi cities that included Jeddah, Khobar, Madinah and Yanbu. This study also examined the possibility of using EGNOS signals for GIS applications. The results indicate that EGNOS correction improved the accuracy of the signals to about 1.5m and lowest precision of about 5m (mean distance). The results show variations from one city to the other. The drawbacks were availability and precision. So, it cannot be used for time-critical projects unless the availability and precision are improved.