Benefit of Rigorous Modeling of GPS in Combined AT/GPS/IMU- Bundle Block Adjustment

The benefit of a rigorous GPS modeling in the combined bundle block adjustment has already been investigated some years ago. However, the closed GPS approach is only used operationally in the subsequent processing with the GEONAP - K package for GPS data and with the BINGO- F package for the combined adjustment. Recently, the BINGO- F package has been extended for the combined adjustment of additional IMU (Inertial Measurement Unit) data. The rigorous GPS approach in a combined GPS/block adjustment uses the actual GPS constellation for the determination of projection center and does not rely on approximative shift and drift parameters, which are generally applied. The advantage is the geometrical constraint of the projection centers within the complete block or at least between individual strips under unfavorable GPS conditions. Changes in satellite constellation do not affect the combined adjustment. The geometrical information from GPS for neighboring strips or the complete block is maintained and strengthen the combined adjustment. The theory of the rigorous GPS modeling will be discussed. For the integrated sensor orientation the correct modeling of all sensor is an essential task. The rigorous GPS approach in a combined bundle adjustment together with IMU and photogrammetric data will consequently also benefit. The European Organization for Experimental Photogrammetric Research (OEEPE) has conducted a multi- site test for the integrated use of AT (Aerial Triangulation), GPS and IMU data. Based on the test, analysis are presented, which focus on the effects of the GPS modeling in the combined bundle block adjustment with the GEONAP- K and BINGO- F software packages.