Delft public domain radar interferometric software: processing considerations and future strategies
EOS Transactions, AGU, 81(19):S162, May-9 2000.
Starting from September 1998, Delft University of Technology is involved in the development of algorithms and software for radar interferometric processing. The design of Doris (the Delft object-oriented radar interferometric software) is based on a number of exchangeable modules, which are subsequently called from a single input file. Standard processing parameters are defined by default, but can be fine-tuned for high accuracy processing. Doris is developed in C++, using a public domain compiler, and designed to work with standard libraries and visualization tools. Currently it uses single look complex data from various sources as input, but preprocessing using a standard SAR processor has been implemented as well. To provide a wide scientific community with interferometric processing capabilities all codes, including documentation, have been made available in the public domain, see http://www.geo.tudelft.nl/doris.html. It is our intention to create a user community and to stimulate user feedback, discussions, and module development. The final goal of the software development is to include geodetic data adjustment and filtering techniques, readily available from many other geodetic techniques, to interferometric processing. Such techniques enable a quantitative evaluation of accuracy and reliability of the parameters of interest. A key aspect of this approach is the definition of the variance-covariance matrix for radar data. Variances between resolution cells in interferograms are influenced by atmospheric propagation variation within the scene, local and global phase unwrapping errors, and orbit errors. We propose to use standard or empirical models to quantify the covariances, and use them in stacks of interferograms for data adjustment and filtering.