Richard Torrealba-Melendez José Luis Olvera-Cervantes Alonso Corona-Chavez Resolution improvement of an UWB microwave imaging radar system using circular polarization. 189-193 2014 CONIELECOMP https://doi.org/10.1109/CONIELECOMP.2014.6808589 conf/conielecomp/2014 db/conf/conielecomp/conielecomp2014.html#Torrealba-MelendezOC14