本論文初步地建置相位靈敏光時域反射儀，可作為分佈式光纖震動感測之應用，其機制是使用窄線寬雷射，經調變形成一道脈衝光，用於分析在待測光纖中有異常或擾動發生時所形成的背向雷利散射光的相位變化。透過文獻探討了解此架構的重要參數如雷射線寬、脈衝寬度與雜訊來源及其解決辦法，線寬可轉換成同調長度，直接地影響感測距離；脈衝寬度則可轉換成空間解析度，亦即最小可偵測異常發生的長度；雜訊來源包括衰退雜訊、極化相關的波動以及背向雷利散射光與本地震盪光的相對相位改變所導致的外差偵測效能波動，個別的解決辦法亦在文獻回顧中提及。
於論文的中段介紹當前的感測系統，包含各元件及儀器在此架構中的功能，同時分析元組件的特性。與文獻中大多使用資料擷取來存取數據及訊號處理相比，本論文透過LabView控制示波器取出平衡式光偵測器轉換的電訊號資料，並用MATLAB做額外的數位訊號處理如數位濾波器、降頻處理及移動平均法來濾除雜訊，可節省設備成本。受限於現有雷射線寬過大使得待測長度不得過長，而待測區長度過短會造成反射的功率過小，不足以讓平衡式光偵測器接收並轉換，目前能達到量測待測長度1.7公里的功能，相位變化的分析仍需進一步改善。

This thesis preliminarily established phase-sensitive optical time-domain reflectometer, which could be used as the application of distributed fiber vibration sensing. Its mechanism was to use narrow linewidth laser and it will be modulated into light pulse that was used to analyze the phase change of Rayleigh backscattering induced by abnormality or perturbation in the fiber under test (FUT). Realizing the key parameters in this architecture, such as laser linewidth, pulse width, noise sources and their corresponding solutions were made by doing survey on the related literature. Laser linewidth could be transformed into coherent length. So, it also affected the sensing length. In terms of pulse width, it could be equivalent to spatial resolution, which meant the minimum detectable length for the location of perturbation. As for noise resources, they were fading noise, polarization-dependent fluctuation and the fluctuation of the heterodyne detection efficiency induced by the relative phase change between RBS light. The individual solution to each noise was mentioned and discussed in the literature review.
Amid the thesis, the experimental set-up, including each component and equipment with the explanation of their functions were introduced, and the characteristics of some components with the theories and experimental results were analyzed as well. Compared to the usage of data acquisition (DAQ) for getting access to the data and digital signal processing (DSP), LabView was used to control digital phosphor oscilloscope (DPO) for extraction of the data, and extra DSP like digital filter, frequency down conversion, and moving average were used to eliminate the noise. Overall, it was cost-efficient way that no extra expense will be spent on DAQ. However, our sensing length too long could not be too long, which in turn resulted in lower reflected optical power that was not enough to let BPD receive and do the optical to electronic (O/E) transformation due to the wide linewidth limit with the equivalence of the shorter coherent length. As a result, the function of measuring the sensing length, whose value is 1.7 km, was achieved, and the improvement on the analysis of phase change is needed.

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