智慧型光放大器之研究

Study of Optical Amplifiers

姚方凱(Fang-Kai Yao)

指導教授 ： 楊淳良

淡江大學/工學院/電機工程學系碩士班/碩士(2012年)

https://doi.org/10.6846/TKU.2012.01168

摘要

在現行的光纖網路裡，光放大器在光纖網路中扮演一個不可或缺的角色。常見的光放大器有摻鉺光纖放大器及半導體光放大器。其中，摻鉺光纖放大器具有高放大增益、高輸出光功率、低雜訊指數、增益不受極化方向影響等特性，適用於各種傳輸速率及各種信號格式，是現階段光放大器的主流。在一般情況下，摻鉺光纖放大器為單一方向放大，可避免反射光訊號造成干擾，故架設在光網路時只允許操作在單一方向傳輸。當傳輸方向需要改變時，則以手動方式重新設置摻鉺光纖光放大器的放大方向。
　　本論文提出一種新光路徑控制單元，其組件包括兩顆2x2光開關、一顆光循環器與一顆光隔離器，以提供智慧型光放大器的設計。它可以突破一般光放大器單一向傳輸的限制，提供光放大方向可逆的功能，以及可以提供光時域反射儀的返回路徑。智慧型光放大器之光放大訊號品質及其功能性也已完成詳細驗證。此外也提出光路徑控制單元之電子控制電路的設計方法，讓智慧型光放大器可自動判斷與切換所需的狀態，達成真正智能功能的要求。

關鍵字

摻鉺光纖放大器 ； 瑞利色散 ； 可逆式光放大器

並列摘要

Optical amplifiers have played an indispensable role in optical networks. Common optical amplifiers contain erbium-doped fiber amplifier (EDFA) and semiconductor optical amplifier. Among others, EDFA has the features of high amplification gain, high output optical power, low noise figure and polarization-insensitive gain, suitable for a variety of data rates and various signal formats. It is at this stage of the mainstream of optical amplifiers. In general, EDFAs are designed for single directional amplification, which can avoid the interference due to reflected optical signals, so they are only allowed at a single direction in optical networks. When the transmission direction changed, EDFA needs manually to adjust its amplifying direction.

This thesis proposes a new optical path control unit that includes two 2x2 optical switches, an optical circulator and an optical isolator, to provide the design of a smart optical amplifier. It can break the limitation of a fixed way transmission for general EDFA, offering the function of reversible amplifying direction. Moreover, it can provide the return path for optical time-domain reflectometer. For the smart optical amplifier, the quality of amplified optical signals and its functionality have also been carefully proven. Furthermore, the design of electronic control circuits for the proposed optical path unit can make the smart optical amplifier automatically determine and switch the required state, achieving the requirement of a truly intelligent function.

並列關鍵字

Erbium-doped fiber amplifiers ； Rayleigh scattering ； Reversible optical amplifiers

參考文獻

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