Accurate Ground Positioning Obtained From 3d Data Matching Between Airborne and Terrestrial Data for Ground Validation of Satellite Laser

GEDI Satellite laser mission will take 3D data globally from International Space Station. The sensor has an improved navigation system to position laser shooting areas accurately. However, the ground validation is still difficult due to the misalignment caused by poor reception of GPS signals under the thick forest. This study introduces a new way to get more accurate ground positioning of trees in tropical forest using 3D data matching technique between airborne and terrestrial data. Our study site is in tropical forest at Robson Creek, Australia. RMSE of XY directions was 0.5 m in and Z direction was 0.6 m, which was impossible to achieve efficiently from the traditional positioning by GPS under dense canopy. The 3D data taken by terrestrial laser is not only useful for capturing structure data for the validation of the waveform analysis of satellite laser but also helps to position accurate ground coordinates in tropical forest through this technique.