FAST AND VALID $\mathrm{H}/\alpha$ DECOMPOSITION COMBINED WITH MODEL-BASED DECOMPOSITION FOR POLSAR DATA

First, since time consumption for extracting
$\alpha$
will become quite tedious for very large images by pixelwise eigendecomposition, we proposed a fast
$\alpha$
angle's solution. Second,
$\alpha$
may be not unique that results in the invalidity of
$\mathrm{H}/\ \alpha$
decomposition. So we early proposed a sound discriminant to distinguish
$\alpha$
is unique or not. Third, since depolarization is serious and
$\alpha$
is unstable in high entropy zone, grass and flourishing canopy etc may be misclassified as double bounce scattering. Therefore we proposed a fast algorithm that
$\mathrm{H}/\alpha$
decomposition is combined with the model-based decomposition, which overcomes the shortcomings of the invalidity of
$\mathrm{H}/\alpha$
decomposition and the misclassification in high-entropy zone, and its time consumption is much shorter than
$\mathrm{H}/\alpha$
decomposition.