Validation Of Dems Derived From Radar Interferometry, Airborne Laser Scanning And Photogrammetry By Using Gps-Rtk

A high resolution digital elevation model (DEM) enables easy, derivation of subsequent information for various applications. This paper uses Real-Time Kinematic (RTK) GPS to examine the quality of some DEMs generated by such means as radar interferometry (InSAR), airborne laser scanning (ALS) and photogrammetry. The preliminary results show that a DEM generated from ALS has the highest accuracy with a RMS error of 0.09 similar to 0.3m. The RMS errors of DEMs derived by photogrammetric and radar interferometric techniques are 1.03 similar to 3.75m and 4.26 similar to 27.81m respectively.