EVALUATION OF OYO STATE COR STATIONS FOR REAL-TIME KINEMATIC (RTK) SURVEY

ABSTRACT The increasing demand for precise and reliable geospatial data in surveying, mapping, and engineering applications has led to the widespread adoption of Global Navigation Satellite System (GNSS) technologies. Among these, the Real-Time Kinematic (RTK) method, supported by Continuously Operating Reference Stations (CORS), offers centimeter-level positional accuracy and eliminates the need for temporary base stations during field operations. This study evaluates the performance, efficiency, and spatial coverage of Oyo State’s CORS network for RTK survey applications. Six CORS stations were identified within Oyo State-FSSC (Oyo), IBAD (Ibadan), ISEY (Iseyin), SAKI (Saki), OGBM (Ogbomosho), and IGBR (Igbo-Ora). However, only three stations (FSSC, IBAD, and ISEY) were operational at the time of this research. Fifteen known ground control points across four local government areas within Oyo Federal Constituency were used for both static and RTK observations. Data were processed using South Geomatic Office (SGO) and Trimble Business Center (TBC) software, and positional accuracies were analyzed through statistical methods, including Root Mean Square Error (RMSE). The results revealed that the FSSC (Oyo) and IBAD (Ibadan) CORS stations provided higher positional reliability, with average RMSE values of 1.50 m (Northing), 0.67 m (Easting), and 0.82 m (Height), while the ISEY (Iseyin) CORS showed relatively higher errors with RMSE values of 2.69 m, 2.18 m, and 1.82 m, respectively. These variations were attributed to factors such as network instability, power interruptions, and environmental influences. The study concludes that the Oyo State CORS network is generally effective for RTK surveying, especially when using the more stable stations. However, improvements in power supply, technical supervision, and network expansion are essential to enhance overall performance. It is recommended that the government and professional bodies implement regular maintenance, ensure consistent monitoring, and integrate the Oyo CORS into the national GNSS framework to sustain high-precision geospatial operations across the state.