寬頻雙圓極化天線於多輸入多輸出通訊系統之應用

Broadband Dual-Circularly Polarized Antenna for MIMO Communication System Applications

施衛辛(Wei-Hsin Shih)

指導教授 ： 林怡成

國立臺灣大學/電機資訊學院/電信工程學研究所/碩士(2010年)

https://doi.org/10.6342/NTU.2010.10599

摘要

本論文提出一寬頻雙圓極化多輸入多輸出天線之設計、實作與量測，以及其在多輸入多輸出系統之應用。與共振型圓極化天線相較，本文所提出的行波型指數曲線槽孔天線擁有更寬頻的圓極化特性與輸入阻抗。針對指數曲線行波型天線，本論文提出數學模型，說明此類行波天線的遠場圓極化輻射機制。本論文所提出的雙極化天線設計，利用指數曲線型槽孔行波天線，整合了左右手圓極化設計於同一元件，使得天線擁有寬頻的圓極化和阻抗匹配特性，而結構中相鄰饋入的雙埠也擁有寬頻的隔離度（|S21|<-15dB）特性。本論文最後以天線實作與模擬結果，計算多輸入多輸出應用中的三項重要系統參數，包括相關度、平均有效增益以及分集增益，藉此說明該雙埠設計的極化分集效能。

關鍵字

行波天線 ； 圓極化 ； 寬頻天線 ； 多輸入多輸出 ； 極化分集

並列摘要

This thesis presents a design of broadband dual circularly polarized (CP) antenna for MIMO communication systems applications. The exponentially-curved aperture antenna of traveling wave type has wider CP bandwidth compared to the resonant type of antennas. We provide a simple mathematical model to explain the CP radiation properties. We integrate right and left handed CP curve-shaped aperture antennas of traveling wave type into a unit module for polarization diversity purpose. The design shows broadband CP performances and isolation (|S21|-15dB) between two proximal ports. In the final chapter, we calculate three important system parameters: the correlation coefficient, mean effective gains, and diversity gains to illustrate MIMO performances on the presented 2-port CP diversity design.

並列關鍵字

traveling-wave antenna ； circular polarization ； broadband antenna ； MIMO ； polarization diversity

參考文獻

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