Fusion of multi-frequency interferometric results by using Kalman filter to generate high quality DEM

Using conventional two-pass interferometry to generate DEM with high frequency SAR data may be confronted with the problem of poor coherence in areas covered by dense vegetation, while DEM generated from low frequency SAR data interferometry is less sensitive to the topographic relief. Therefore, this article aims at generating high quality DEM by fusing multi-frequency interferometric results obtained from two-pass interferometry by using Kalman filter. Meanwhile, a process of coregistration of multi-frequency SAR data which are of different pixel sizes and imaging geometries is proposed. And data from Envisat ASAR and TerraSAR-X are used for case study and the accuracy of fused DEM are verified by ASTER GDEM.