Technical Note on POlarimetric Phase Interferometry (POPI)
  The Global Navigation Satellite Systems (GNSS), such as the American Global Positioning System (GPS), the Russian GLONASS or the imminent European Galileo, can be used as sources of opportunity for remote sensing of the Oceans. In this document, we present the approach, conceptual background and preliminary results of a novel polarimetric interferometric technique based on GPS signals rebounded off of the sea surface and collected at both Right Hand (RH) and Left Hand (LH) Circular Polarizations. We seek to obtain geophysical information out of the phase information, which could be in principle relate to the dielectric properties of the sea surface. 
Estel Cardellach, Serni Rib\'o, and Antonio Rius