分佈式光纖感測系統由於它是以光纖作為感測介質，具備體積小、抗電磁干擾、能在惡劣的環境中使用等優勢，且可實現長距離、大範圍、多參量的感測。特別適用於大型土木工程、光纖通訊、石油化工、電力工業等高危險領域的結構健康監測，是目前國內外感測技術研究的熱點。基於受激布里淵散射的布里淵光時域分析(BOTDA)和基於雷利散射的相位靈敏光時域反射(φ-OTDR) 是兩種重要的光纖感測技術，也是本論文討論的主題。
本研究之主要目的在於結合布里淵光時域分析系統與相位靈敏光時域反射系統。BOTDA技術主要用於應變與溫度的測量，具有高精度和長距離的優點，但BOTDA泵激光與探測光雙端接入進行感測，這也代表當光纖出現斷點時，BOTDA系統將不能正常運作，限制了BOTDA的應用場合。因此透過結合相位靈敏光時域反射，具有光纖監測功能且還可以用於震動的感測，加上前述的雙參數量測，達到三參數測量，在實際應用上也十分重要。
透過參考光纖法，利用兩種不同布里淵頻率之光纖，其中一種光纖作為參考光纖(處於不受應變干擾)，而另一種光纖作為量測光纖(受到溫度及應變同時干擾)。將兩種光纖放置很近比擬成受到環境的干擾接近，接著透過參考光纖受到周圍環境溫度的變化，得到溫度的變化量，再由量測光纖的變化扣除參考光纖的溫度變化，即可獲得光纖的應變變化量，實現溫度與應變的區分量測。
藉由文獻探討蒐集的資料進行實驗研究，將系統的各項參數進行實驗研究，首先針對BOTDA系統透過電光調製器的移頻效果與可調式濾波器輸出通道調整以及探測光與泵激光比例的調整，達到本系統感測距離29公里，空間解析度2公尺。接著是φ-OTDR系統，透過調整入射光至待測光纖前功率避免受激布里淵效應的干擾以及濾波器輸出調整，最後訊號處理，達成本系統感測距離5公里，空間解析度10公尺且震動點的SNR值為4.52。

Distributed optical fiber sensing systems are small in size, have anti-electromagnetic interference, can be used in harsh environments, and can measure long-distance, large-scale, multi-parameters due to their use of optical fibers as the sensing medium. It is especially suitable for structural health monitoring in high-risk fields such as large-scale civil engineering, optical fiber communication, petrochemical, and the electric power industry. Brillouin Optical Time Domain Analysis (BOTDA) based on Stimulated Brillouin Scattering and Phase Sensitive Optical Time Domain Reflectometry (φ-OTDR) based on Rayleigh Scattering are two important fiber sensing techniques and are also discussed in this paper theme.
The primary purpose of this research is to combine the Brillouin optical time-domain analysis system with the phase-sensitive optical time-domain reflectometry system. BOTDA technology is mainly used to measure strain and temperature, which has the advantages of high precision and long distance. Still, the BOTDA pump light and probe light are connected at both ends for sensing, which means that when the fiber breaks, the BOTDA system will not work properly The operation limits the application of BOTDA. Therefore, combining phase-sensitive optical time domain reflection, has an optical fiber monitoring function and can also be used for vibration sensing, which is not only of academic value but also very important in practical applications.
Through the reference fiber method, two kinds of fibers with different Brillouin frequencies are used as the reference fiber (under strain interference), and the other fiber is used as the measurement fiber (under both temperature and strain interference). Both kinds of optical fibers are placed close to each other and are not disturbed by the environment.. Then the temperature change is obtained through the ambient temperature change through the reference fiber. Then the temperature change of the reference fiber is deducted from the change of the measurement fiber to obtain the fiber. The amount of strain change can be achieved to distinguish the measurement of temperature and strain.
Experimental research is carried out based on the data collected from the literature research, and the system parameters are experimentally studied. First, the frequency shifting effect of the BOTDA system through the electro-optical modulator, the adjustment of the output channel of the tunable filter, and the adjustment of the ratio of the probe light and the pump light, reaching a sensing distance of 29 kilometers and a spatial resolution of 2 meters. Next is the φ-OTDR system, which avoids the interference of the stimulated Brillouin effect and adjusts the output of the filter by adjusting the power of the incident light before the fiber is tested. Finally, the signal is processed to achieve a sensing distance of 5 kilometers and a spatial resolution of 10 kilometers and the SNR value of the vibration point is 4.52.

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