Research On Techniques Of DEM Generation With Multi-Baseline Sar Interferometry

With the development of digital army, Multi-baseline Interferometric synthetic aperture radar(InSAR) has been the most portencial surface information acquisition technologies for virtual battlefield. It is a fast, high precision and stability technique to obtain digital elevation models(DEMs). However, the DEM obtained by multi-baseline InSAR is not accurate enough. In this paper, the acquisition method of elevation is improved to get a higher accuracy, especially the technologies of multi-baseline phase unwrapping and phase to height conversion.First of all, sereval classical phase unwrapping algorithms was compared. Aiming at the low accuracy of the phase unwrapping algorithm under actual noise which is non-normal distribution, a new adaptive covariance matrixs constructed based on the model of the multibaseline optimal weighted data(MOWJD)vector, and the noise was removed by noise covariance matrix.Secondly, Aiming at the inconsistent noise between different pixels, a new error matrix constructed. The m-norm of the error matrix is calculated to control the times of iterations.Then, sereval classical phase unwrapping algorithms was compared. Aiming at the low accuracy and continuity of elevation acquisition aligorithm, a new Joint Elevation Data method was proposed to get a higher quality.Finally, the whole InSAR-DEM system realized by MATLAB R2007. The Adaptive Covariance Matrixs Multibaseline Optimal Weighted Data algorithm and the Joint Elevation Data method was realized.