新型超穎材料電路單元應用於雙頻延伸型CRLH洩漏波天線

Abstract

在本論文中，我們提出一個新型超穎材料電路單元應用於雙頻延伸型複合式左右手洩漏波天線設計。其電路單元結構是基於E-CRLH傳輸線設計，以微帶線技術和集總元件來實現，且由傳統複合式左右手與對偶型複合式左右手的電路單元雛型所合併而成。這個電路結構提供了兩組左右手的導通帶，以及在延伸的平衡條件下，存在兩個零傳輸常數的頻率點。藉由這超穎材料獨特的特性，我們設計出一個含有十個平衡型E-CRLH電路單元的直線型雙頻洩漏波天線。這個雙頻洩漏波天線在兩個頻帶具有連續性波束由後向往前向掃描，甚至包含垂向掃描，不同於傳統洩漏波天線與現有的C-CRLH洩漏波天線只有單一頻段掃描特性，而且我們所提出的洩漏波天線沒有額外的匹配網路與複雜的饋入電路去激發高階模。此外，本設計以平面印刷電路技術實現，易與其他平面印刷電路進行整合。

In this thesis, we propose a novel metamaterials unit cell for dual-band extend composite right/left handed (E-CRLH) leaky wave antenna. The unit cell structure is based on E-CRLH transmission line implemented in microstrip line technology and lump element, and constituted by the combination of the conventional CRLH and dual CRLH unit cell prototypes. This structure provides two pair of left/right-hand passbands and exhibits two frequencies of zero propagation constant under an extended balance condition. By this unique properties of the metamaterials, we designed a straight dual-band leaky wave antenna which consists of 10 balanced E-CRLH unit cells. This dual-band leaky wave antenna exhibits beam scanning from backward to forward and even through broadside continuously for each band, and it is different from the conventional leaky wave antenna and the latest CRLH leaky wave antenna which scan in single band. The advantage of the novel LWA is without additional matching network and complicate feeding circuit to excite high-order mode. In addition, the propose design is implemented by printed circuit board technology, and make it easy for integration with other circuits.