Ultra Wide Band horn antenna design for Ground Penetrating Radar: A feeder practice

Ultra-Wide Band (UWB) technology in Ground Penetrating Radar (GPR) imaging has been an interested research topic for the last couple of decades. Although there have been a lot of work and research conducted on this subject, there c still interested research matters that has to be studied. UWB directional antennas are one of the critical components for UWB-GPR applications. The parameters of the antennas that are used within the system affect the performance of the application. The horn antenna; for example, can give the focusing ability needed in some applications thanks to its high directivity feature. Although there are many parameters that affect the design of a Horn antenna, aperture size and the feeder type are commonly used parameters to obtain wider frequency operation. In this study, the effect of different feeding structures on frequency bandwidth for a fixed waveguide dimensions are investigated and the results are shared. For this purpose, various feeding structures that are straight wire feeder, spherical feeder, cylindrical feeder and conical feeder are examined and the simulated and the measured bandwidth results are presented. Furthermore, we propose a new feeder type that provides better simulation results in terms of bandwidth is introduced. With this new structure, the horn antenna is optimized using an antenna simulation software; CST-Microwave Studio and the corresponding produced antenna is measured to complete the design.