基於人造導磁體結構來改善倒 F 天線的特性

The Performance Improvement of the Inverted-F Antenna Based on the Artificial Magnetic Conductor

本文主要是提出並製作以人造磁導體(Artificial Magnetic Conductor, AMC)理論為基 礎的架構，此架構與倒F 天線(Inverted F Antenna)結合能夠改善天線的增益，分別使 用三種不同樣式的AMC 架構來探討。人造磁導體的架構能夠模仿完美磁導體的性質並 產生相位零點。各個架構所建立的電路模型被用來驗證AMC 對倒F 天線的增益與頻寬 關聯性。倒F 天線採用CPW(Coplanar Waveguide)饋入方式是為了增加天線的頻寬， 天線操作頻帶在5.12-6.16GHz，並模擬不同形式的AMC 對倒F 天線的場型與增益有何 影響，其結果證實AMC 架構確實能夠有效改善天線特性，頻寬約增加0.53GHz，最大 增益可達到5.3dB。

 

In this paper, the structure based on the Artificial Magnetic Conductor is proposed and fabricated. It is applied to improve the realized gain of the inverted-F antenna. Three different AMC structures are investigated. The AMC structure can provide the similar characteristic of the perfect magnetic conductor (PMC) surface and introduce a zero degree phase shift. The circuit model for each structure is created to verify the sensitivity of the related electrical properties to the gain and bandwidth of the inverted-F antenna. The coplanar waveguide (CPW) feeding is adopted to increase the bandwidth of the inverted-F antenna. The operating bandwidth ranged from 5.12 GHz to 6.16 GHz is achieved. The pattern and gain of the inverted-F antenna using different AMC structure are simulated. It is shown that the AMC structure is proven to be effective in improving the antenna performance. The bandwidth is increased by 0.53GHz and the maximum gain is 5.3dB.