On the basic principles of radar polarimetry  The target characteristic polarization state theory of Kennaugh, Huynen's polarization fork concept, and its extension to the partially polarized case
Abstract
Basic principles of radar polarimetry are introduced. The target characteristic polarization state theory is developed first for the coherent case using the three stage, the basis transformation, and the power (Mueller) matrix optimization procedures. Kennaugh's and Huynen's theories of radar target polarimetry are verified for the monostatic reciprocal case. It is shown that there exist, in total, five unique pairs of characteristic polarization states for the symmetric scattering matrix of which two pairs, the crosspolarization null and copolarization max pairs, are identical, whereas the crosspol max and the crosspol saddlepoint pairs are distinct. The theory is verified by an example for which next to the polarization fork the copolarized and crosspolarized power density plots are also presented. The partially polarized case for completely polarized wave incidence is presented and compared with the results for the coherent and the partially coherent cases, the latter of which is still unresolved.
 Publication:

IEEE Proceedings
 Pub Date:
 October 1991
 Bibcode:
 1991IEEEP..79.1538B
 Keywords:

 Optimization;
 Polarimetry;
 Polarized Electromagnetic Radiation;
 Radar Transmission;
 S Matrix Theory;
 Computer Graphics;
 Cross Polarization;
 Lagrange Multipliers;
 Null Zones;
 Poincare Spheres;
 Communications and Radar