Joint Use of Scattered and Received Wave Polarization Information for
Target Characterization and Scattering Power Decomposition
Abstract
This manuscript was submitted on 31 December 2019 to IEEE Transactions
on Geoscience and Remote Sensing.
Abstract: Incoherent
target decomposition techniques provide unique scattering information
from polarimetric SAR data either by fitting appropriate scattering
models or by optimizing the “received” wave intensity through the
diagonalization of the coherency (or covariance) matrix. Hence, the
information provided by the “scattered” wave might be neglected. This
scattered wave information can be well utilized to gain complete
polarimetric information for numerous applications. In this study, a new
roll-invariant scattering-type parameter is introduced, which jointly
uses the degree of polarization as the “scattered” wave information and
the elements of the covariance matrix as the “received” wave
information from both full-polarimetric (FP) and compact-polarimetric
(CP) SAR data. This scattering-type parameter, which is comparable to
that of the Cloude $\alpha$ for FP SAR data and the
ellipticity parameter $\chi$ for CP SAR data, can be
well utilized to characterize various targets. Furthermore, this new
scattering-type parameter is adequately utilized to obtain a non-model
based three-component scattering power decomposition technique. The
double-bounce and the odd-bounce scattering powers are obtained by
modulating the total polarized power by a proper geometrical factor
easily derived using the new scattering-type parameter for both FP and
CP SAR data. Moreover, due to its natural and direct formulation, the
decomposition scattering powers are non-negative and roll-invariant
while the total power is conserved. The proposed method is qualitatively
and quantitatively assessed utilizing the L-band ALOS-2 and C-band
Radarsat-2 FP and the associated simulated CP SAR data.