Comparative Study of Positional Accuracies Using Three GPS Receivers

The emergence of the Global Positioning System (GPS) receiver over the years has afforded the avenue to acquire data from various geospatial locations. This paper analyses and compares the accuracy of point positions collected using three Global Positioning System (GPS) receivers— South H66/H88, Sokkia radian IS, and ProMark 3. A field study was conducted on 5 control points within the Federal University of Technology Akure (FUTA) Campus. The One-way ANOVA test performed for the coordinates obtained from the three GPS receivers at an alpha level of 0.05 using SPSS version 16 reveals no statistically significant difference between the coordinates. Analysis of the result shows that South GPS, Sokkia GPS, and ProMark GPS receivers had horizontal misclosure values of 0.1337, 0.1625 and 0.2425 respectively, making South GPS best in obtaining accurate information on horizontal positions. For the vertical position, misclosure values of 0.0902, 0.2336, and 0.2771 respectively were obtained for the Three GPS receivers, thereby revealing that Sokkia GPS performed optimally in obtaining heights above the ellipsoid. However, as a combination of horizontal and vertical positions (3-Dimension), Sokkia GPS performed best while ProMark GPS performed averagely and South GPS performed least. This study shows that any of the three GPS receivers can provide reasonable accurate geographic data. However, a definite conclusion remains that the selection of an optimal GPS receiver in this study for any project will largely depend upon the user’s needs and project requirements as the significant variation observed in the height coordinates should be further investigated.