Satellite radar interferometric products for the urban application domain

摘要

Data integration is a key issue in environmental monitoring systems especially if ground-based data has to be fused with remotely sensed information. This paper presents some techniques to extract information from satellite radar imagery and to prepare it for further use in the data integration chain for urban monitoring. The potential of spaceborne earth observation (EO) to meet some of the requirements for urban monitoring is high, but not fully recognized. In particular, the potential of radar interferometry for the urban application domain is not yet evaluated. The main objective of the project described in this paper was to analyze the benefits and the limitations of ERS-InSAR data analysis for urban monitoring. The evaluation focuses on three main applications: monitoring small surface movement (e.g. subsidence, dunes, crustal movements); change detection analysis (urban sprawl monitoring); and the generation of Digital Elevation Models (DEMs). Using the technology of repeat-pass radar interferometry, there are three different products to process for the urban application domain: coherence, DEM and differential InSAR. The method of InSAR processing was tested at two validation sites, Cairo and Taipei, which are different in size and urban structure and which are also located in different climatic and vegetation zones. The results of the interferometric analyses have finally to be integrated into urban information systems for further value adding processing or thematic analyses. In future, the recently available ready-to-use interferometric products (e.g. spot image coherence products) will reduce the complex processing effort required to use radar interferometry data. There will be a load-and-go solution to simply use interferometric products in urban monitoring.