The Synergy of Optical VHR/HR Satellite Images and TerraSAR-X StripMap Data in Early and Rapid Agricultural Crops Mapping

The paper presents the methodology and results of early agricultural crops mapping achieved with TerraSAR-X StripMap images acquired at single and dual polarization mode, during spring and summer 2008 over test site Malbork in Northern Poland. Two types of images in time sequence were ordered and acquired: stripNear_013R, VV/VH and strip_007R, VV. The first TSX observations and Rapid Field Visits started at the moment just after spring cereals have been emerging over the soil but not yet influencing radar backscattered signal coming from soil. Two short-time TSX series were analyzed from crops identification's point of view regarding differences of: viewing angles between strips R013 and R007, radiometric and speckle characteristics of VV channel in single and dual pol. mode, significance of cross polarization component. The methodology of data analyses was subordinated to CAP/JRC/CwRS requirements demanding the maximum reliability and accuracy in crops mapping before the harvest. In this perspective TSX dataset was supported by optical IKONOS image taken the same day as the first TXS image (25.04.2008) and three input dataset were created for automatic classification purposes: 1) TSX images only, 2) VHR optical data and 3) merged radar-optical "product". The results of classification are the main output from this methodological approach.