雙頻電磁能隙結構設計及其應用

Abstract

本計畫為雙頻/多頻電磁能隙（dual-/multi-band electromagnetic bandgap, EBG）結構研究並應用於 天線設計。EBG 結構的應用十分廣泛，而近年來EBG 結構作為高阻抗平面（high-impedance surface, HIS） 為學術界熱門的主題之一。高阻抗平面可視為一人工磁導體（artificial magnetic conductor, AMC）。天線設計 常因天線太接近金屬接地面（ground plane），而導致輻射效率不佳。若以人工磁導體取代電導體（electric conductor）接地面，則可增加輻射效率並大幅縮小天線體積。然而，目前所見EBG 結構大多操作於某一特 定頻率，而現有的雙頻/多頻EBG 結構需要多層結構。本計畫擬開發雙頻/多頻EBG 結構，並著重於將此 EBG 結構平面化、縮小化，以減少所需體積和製作成本，並應用於雙頻/多頻天線的設計上。 第一年計畫（2008/8-2009/7）

The major purpose of this project is to develop the dual-/multi-band electromagnetic bandgap (EBG) structure and its application on antenna design. The EBG structure has broad application. In recent years, the realization of high-impedance surface (HIS) by EBG structure is one of the popular issues. High impedance surface can be used as an artificial magnetic conductor (AMC). In antenna design, the radiation efficiency is low when the antenna is too close to the metal ground plane. If we replace the electric conductor ground plane by AMC ground plane, the radiation efficiency will be enhanced and the volume of the antenna will be reduced. However, most of the EBG structures are operating in single frequency-band. The dual-/multi-band EBG structures nowadays are constructed by muti-layer structure. In this project, we develop the dual-/multi-band EBG structure, and focus on compact, miniaturized, and planar design to reduce the volume and cost. The application on dual-/multi-band antenna design is also proposed. In the first year（2008/8-2009/7）