Linear to circular polarization transformation of vivaldi antennas and its use in GPR detection

Abstract

An antipodal Vivaldi antenna is designed for use in the ground penetrating radar (GPR) detection of landmines. Two such antennas, one transmitting and one receiving, are connected to an ultra-wideband GPR to record the responses of exact models of certain types of landmines. Later, a periodic structure converter is used to transform the antennas' linear polarization into circular polarization. The responses obtained from the same landmine models upon making the linear to circular polarization transformation show more information, and as a result are better fit for employment with signal processing algorithms aiming at detecting and classifying buried landmines. The results for the antenna design, polarization conversion, and GPR responses with both linear and circular polarization are reported.