Urban Damage Mapping Using Fully Polarimetric SAR Data

Damage extents and damage levels of destructed urban areas are essentially important information for rescue planning after a large-scale natural disaster. Spaceborne synthetic aperture radar (SAR) can provide quick response and huge area monitoring to mitigate the further loss. Automatic and accurate mapping of urban damage levels with SAR is still challenging. Polarimetric SAR (PolSAR) has the better potential to understand urban damage conditions from the viewpoint of scattering mechanism investigation. Polarimetric coherence is an important source for PolSAR data investigation. The variation of polarimetric coherence in the rotation domain along the radar line of sight contains rich hidden information which relates to target orientation diversity effect. This work focuses on the hidden signature exploration of co-polarization coherence in the rotation domain for urban damage investigation. A damage index is proposed based on the interpretation tool of co-polarization coherence pattern and an urban damage level mapping approach are established. Experimental studies are carried out for the study case of the great 3.11 East Japan earthquake and tsunami using multi-temporal ALOS/PALSAR PolSAR data. Comparison studies validate the efficiency of the developed mapping approach.