The effect of one point, network and PPP GNSS data processes on the direct sensor orientation accuracy

Direct sensor orientation or direct georeferencing is the solution of exterior orientation parameters using GNSS\IMU data without ground control points. Accuracy of the system is based on GNSS\IMU integrated system accuracy. The integrated system containing DGNSS and IMU calculates the approximate exterior orientation parameters during the flight. The exterior orientation accuracy is based on GNSS and IMU accuracy. In this study, the effect of one point, network and PPP GNSS data processes without ground control point on the accuracy of the direct sensor orientation was evaluated. Test area is 1296 km2. It was used 393 images with 30 cm resolution. It was calculated that one point solution horizontal accuracies are (X-Y) 23-30 cm., vertical accuracy is (Z) 40cm, network solution horizontal accuracies are (X-Y) 24-27 cm, vertical accuracy is (Z) 37 cm and ppp solution horizontal accuracies are (X-Y) 20-28 cm, vertical accuracy is (Z) 37 cm.