Application of Indian space-based augmentation service on geospatial data collections in Sri Lanka

GPS Aided Geo Augmented Navigation (GAGAN) is the Indian Satellite-based Augmentation System, fully operational since 2013 with the objective of providing the accuracy and integrity required for civilian and aviation applications. This study investigates the usability of GAGAN service as an accurate, reliable and a cost-effective source of positioning and navigation for geospatial applications in Sri Lanka. Point, line and polygon features were collected under different challenging conditions to test the usability and potential accuracy of GAGAN. The average 3D positional accuracy enhancement over SPS is about 70 and 78% for GAGAN and DGPS observations, respectively. Similarly, the average GAGAN enhancement over SPS observation was 79% and 83% for linear and area measurements, respectively, and the improvement for DGPS was 86% for both feature types. This confirms that GAGAN can improve geospatial data collection accurately, almost similar to DGPS without a use of local reference station, or national CORS networks.