On the similarity between dual- and quad-eigenvalue analysis in SAR polarimetry

Abstract

This study clarifies the difference in eigenvalue analysis between quad-, HH/VV dual- and HH/HV dual-polarization synthetic aperture radar (SAR) data (HH, HV and VV represent horizontal transmission horizontal reception, horizontal transmission vertical reception and vertical transmission vertical reception of microwaves, respectively). There are different types of data acquisition modes in SAR systems and each one of them has different advantages and disadvantages. The main advantage of quad-polarization data is more detailed information about scattering objects, and those of dual- or single-polarization data are higher spatial resolution, wider area coverage and abundance of available data sets. Thus, there is a certain trade-off between the SAR data of these acquisition modes, and in the present study, we focused on the potential information contained in the dual-polarization data using the Advanced Land Observation Satellite-Phased Array L-band SAR (ALOS-PALSAR) quad-polarization data of the Tokyo Bay, Japan. It was found that the HH/VV dual-polarization data can produce very close entropy/alpha results to quad-polarization data, whereas only entropy is reliable in HH/HV dual-polarization data.