The comprehensive design of high efficiency monopole plasma antenna using surfaguide exciting method

Abstract

In this study, designing procedure of a monopole plasma antenna excited by microwave surface waves was investigated. Improving the antenna efficiency, the surfaguide structure was used as a surface wave launcher at 2.45 GHz which could produce a plasma column and increase the plasma conductivity. Moreover, the antenna was fed directly via the input connector instead of the coupling sleeve in the conventional feeds using capacitive coupling method. Using these two techniques, the antenna performance was increased and it reduces the loss due to the coupling power from the source to the plasma column. Plasma column was modelled using Finite Element Method (FEM) with COMSOL MULTIPHYSICS software. The antenna parameters such as return loss, radiation pattern and gain were investigated using CST simulation. The designing procedure was performed for monopole antennas with lengths of l = 62 cm and l = 32 cm which resonate at 145 MHz and 200 MHz, respectively. The simulation results show acceptable adaptation in respect to the experimental measurement and increase significantly in the antenna gain compared with the previous ones.