Improved scattering-model-based speckle filter of polarimetric SAR data

An improved speckle filter that preserves scattering characteristics for polarimetric SAR images is proposed. Lee proposed a scattering model based filter for polarimetric images in 2006. It is derived from the Freeman Decomposition to ensure that only the pixels belonging to the same scattering characteristics are included for filtering. However, some urban areas will mix up with the vegetated areas in the model-based decomposition, which confronts with the basic concept of the filter and decline the filtering effect. An improved four-component polarimetric decomposition is applied to overcome this problem. The proposed filter include the orientation angle compensation of the scattering matrix, a new volume scattering model, and two power constraints to deal with the previous problems. Experimental results indicate that the proposed algorithm have acquired an improved filtering effect for polarimetric SAR images.