改良型寬頻後設材料電路單元之寬頻、高增益切換式多平面掃描CRLH 洩漏波天線設計

Designs of Broadband and High gain Switched CRLH Leaky-Wave Antenna with Multi-Plane Scanning Capability of Improved Broadband Metamaterial Unit Cell

林辰宇(Chen-Yu Lin)

指導教授 ： 陳富強

國立交通大學/電機學院/電信工程系所/碩士(2017年)

摘要

本論文提出一改良型寬頻後設材料電路單元之寬頻、高增益切換式多平面掃描CRLH洩漏波天線設計。而藉著調整電路單元的結構可設計出寬頻或高增益的CRLH洩漏波天線，設計理念以實驗室學長設計出的蕈狀結構與MIM(metal-isolator-metal, MIM)電容結合之結構為設計基礎，藉由設計調整MIM電容的大小來改變由蕈狀結構所產生出的高階共振腔頻率，即可設計出為原本頻寬5倍寬的電路單元。而透過這電路單元達設計以及調整，更可建構出一維寬頻或高增益的CRLH天線，其擁有輻射波束隨著頻率由後向至前作連續性掃描之特性，這也是CRLH天線近年來廣違背研究與關注的原因。
接著將兩組一維CRLH洩漏波天線呈交叉型擺設，並在交叉旁的電路單元上各加上一組PIN DIODE，藉由控制不同PIN DIODE導通情形來切換不同的洩漏路徑達到Beam Forming，也因此讓天線具有多個輻射的平面可以選擇，為一可切換平面輻射的智慧型天線。此外，本設計採用平面印刷電路板以及微帶線饋入技術所實現，其電路結構輕薄簡單，易與其他平面印刷電路作整合。

關鍵字

寬頻 ； 高增益 ； CRLH 洩漏波天線 ； 智慧型天線 ； 蕈狀結構

並列摘要

This thesis provides a modified CRLH unit cell. By adjusting the unit cell, we can design a wide band CRLH leaky wave antenna or high gain CRLH leaky wave antenna.
The original unit cells consisting of mushroom structures and MIM capacitors made by my senior Rung-Yuan Chang. However, the drawback of that unit cell is the narrow bandwidth. Therefore, this thesis proposed a modified five times wider bandwidth unit cell, by changing the configuration of the MIM capacitance to move the higher resonant cavity frequency. Then, with the proper adjustment of the higher resonant cavity frequency, we can make a 1-D wide band or high gain CRLH leaky wave antenna which can continuous scan from backward to forward angles with the radiation beam. The special characteristic of the CRLH leaky wave antennas is the reason why widely been researched and focused.
Furthermore, we proposed a modified symmetry unit cell, then we place two sets of 1-D balanced wide band CRLH leaky-wave antenna in a cross-type structure and put the unit cell at the middle. Besides, we install RF switching circuits aside to the modified symmetry unit cell. By controlling those PIN-diodes, we can switch different leaky paths to achieve multi-plane scanning capability. This modified circuit combines the properties of beam-switching and beam-scanning antennas. In addition, all proposed elements of this invention are implemented by planar printed circuit board technique, which is low-profile, simple and easy to be integrated with other planar printed circuits.

並列關鍵字

Broadband ； High Gain ； CRLH Leaky-Wave antenna ； Smart Antenna ； Mushroom

參考文獻

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