封裝微帶線電路中部分封閉吸收性共振腔之分析

Abstract

本論文主旨在提出並分析一種在封裝微帶線電路中部分封閉吸收性共 振腔結構．這種結構的作用在將容易激發高階模的電路與其它電路區隔開 ，使所激發的高階模被侷限在□面，並且被吸收掉，同時又不會干擾到微 帶線主模的傳播．此封裝微帶線共振腔是由前後兩片金屬板組成，中間再 加上吸收性介質材料．論文中採用線方法配合模態匹配分析法分析．首先 將分析兩片金屬隔板對主模及高階模的耦合效應，其次分析介質層的位置 ，寬度，深度及隔板間距，對共振腔特性的影響． In this thesis we propose and analyze a partially sealed absorbing cavity in a packaged microstrip circuit. This structure is formed by absorbing dielectric layers attached on the top cover of the packaged microstrip circuit and sandwiched by two metal diaphragms. Any device which tends to excite higher-order modes (parasitic modes) may be designed inside this cavity so that the excited higher-order modes are confined by the diaphragms and decayed by the absorbing layers. The method of lines coupled with the mode-matching method will be adopted to investigate this structure. The coupling effect, with respect to the microstrip dominant mode and higher-order modes, of two metal diaphragms will first be analyzed, and then the influences, on the characteristics of the cavity, of varying the position, width, and depth of the absorbing layers and the distance between the diaphragms will be investigated.