本論文於第一部分提出一款周期性洩漏波天線利用簡單的平面架構提供隨頻率掃描的圓極化輻射波束。此天線由平行雙線傳輸線串聯的相位反相器組合而成，電磁輻射是由相位反相器中部連續結構所造成，因此為一組洩漏波天線。
模擬與實測結果可觀察出寬頻的掃描範圍中，有不錯的圓極化效果。
第二部分為運用於2.4 GHz，MIMO用途的電子調控波束切換陣列天線，此陣列天線包含了洛德曼透鏡以及四組貼片天線，其中洛德曼透鏡為相位延遲裝置，可同時操作多組波束。從實驗結果可以觀察，若洛德曼透鏡搭配簡單的切換裝置，相當適合用於MIMO收發機。

In this thesis, the proposed periodic leaky wave antenna, which has a simple planar geometry, provides a circularly polarized beam steerable via frequency scanning. The antenna comprises serially connected phase inverters made of parallel strip line. Radiations emit from geometric discontinuities in phase inverter structures and hence form a leaky wave antenna. From simulation and verification results, broad scanning beam coverage is observed with good circular polarization performance.
In the second part, an electronically reconfigurable beam switching array antenna applicable to MIMO technology in the 2.4 GHz band is proposed in this work. The array antenna contains a Rotman lens and four element antennas. The Rotman lens, which is a true time delay device, allows simultaneous operation of multiple beams. From the results, the simple beam switching mechanism implemented with the Rotman lens suits well to the MIMO transceiver need.

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