Interferometric SAR Extended Coherence Calculation Based on Fractional Lower Order Statistics

A polarimetric synthetic aperture radar (SAR) coherence calculation method based on fractional lower order statistics (FLOS) was proposed in Bian's paper. In this letter, we apply this approach to the coherence calculation for interferometric SAR (InSAR) and provide a detailed analysis. An L-band InSAR data set is used to provide comparative results between the coherence derived in the traditional manner and that based on FLOS. In the areas around strong scatterers, the coherence is found to be biased due to the deviation of the statistical model from Gaussian when using the traditional coherence calculation. However, the coherence based on FLOS largely reduces this bias. From the experimental results using the InSAR data, we found that this method reduces the artifacts in the traditional coherence calculation method. The removal of bias due to sample estimation is also discussed.