Artificial Magnetic Conductor Structure And Antenna

In recent years, the artificial magnetic conductor (AMC) structure as one of hot topics has been investigated in the research area of microwave and millimeter wave technology. The structure is simple and easily manufactured, which is mainly used to improve the performances of RF components. In this thesis, the applications of the AMC structure on the microstrip antenna have been presented.Firstly, the method analyzing the reflected phase band-gap of the AMC structure has been presented. Furthermore, focusing on the Electromagnetic band-gap (EBG), one structure of AMC, the investigations of its stop-band have also been given. Secondly, the applications of AMC structure to microstrip patch antenna and antenna array are researched in this thesis. For the application of microstrip antenna element, the AMC structure has been used to instead the ground plane of the antenna. With this modification, the high-gain and wide-band antenna element is achieved. Compared with the conventional patch antenna using the same thickness dielectric substrate, the simulated results of this novel patch element show that the bandwidth is increased by 250%, and the gain is increased by 1.41 dB. Further, three cases of 2X2 antenna array utilizing the AMC are discussed. The three cases are listed:case 1 is the AMC only insteading the ground plane of the antenna elements of 2×2 array; case 2 is the AMC structure insteading the ground plane of the 2×2 array; case 3 is the AMC only insteading the ground plane of antenna elements, however, the ground plane of feeding network has been elevated. The VSWR, radiation patterns and gains of three cases are compared. Among them, the best one has been fabricated and tested. The measured results show approximately 20.45% relative bandwidth and the maximum gain in the frequency working band is 15.95dBi.