Design and Analysis of X-Band Waveguide Feeder Structure with Dominant Mode Transmission Enhancement Using Tuning Stubs

During the last decade, the guided wave structures played a key role in numerous microwave systems. They have been deployed in many applications such as radar, remote sensing, and satellite applications. Furthermore, such guided wave structures have various advantages in a term of the strength of the structure, high power handling capability, efficiency, and small dimensions which make them more appealing to be employed in microwave frequency range applications. In this paper, design, analysis and comparison of structures for radar applications with enhanced performance using impedance matching, has been obtained. The $TE_{10}$ transmission enhancement obtained through two varieties, the first variety is the feeder with straight output ports and the second is the feeder with V-output ports for V-antenna applications. The enhancement transmission ratio (ETR) is the ratio of transmission of both structures with and without stub. Structures have been analyzed using HFSS and CST. The proposed structures presents ETR for TE10 up to 17.7 and 28.8 at 11.43 and 8.12 GHz for both varieties respectively compared to the conventional feeders without stubs using HFSS simulator. The same structures present ETR for TE10 up to 17.6 and 28.7 at 11.93 and 8.63 GHz using CST simulator. The proposed structures characteristics such as the magnitude of transmission coefficient, log scale distribution of current on surface and the ETR are obtained to demonstrate the performance of structures using HFSS and CST simulators.