本論文有包含自製窄線寬光纖雷射的增進，與φ-OTDR系統的距離延長兩個部分，其中分別介紹了窄線寬光纖雷射與φ-OTDR系統架構的建置與原理的介紹，提及內部元件的介紹與該元件在架構中的作用，並展示最終研究成果。自製窄線寬光纖雷射的部份有功率上的提升與線寬的進一步縮小，提高雷射穩定度，並嘗試使用自製窄線寬光纖雷射結合φ-OTDR系統進行長距離震動感測。其中的雷射功率的增進，從去年成果2.816mW提升至56.3mW，增進了約20倍功率，線寬的部分從去年成果4.176kHz縮窄至1.335kHz，穩定性的部分也有一定程度的提升。
φ-OTDR系統的部分為，將距離從4.6km感測距離延長至10.1km，改良架構的建製與脈衝重複率參數的設定，調控架構內的功率，使φ-OTDR系統成功定位到10.1km距離的模擬震動源位置，並且擁有10公尺的空間解析度與4.9dB的SNR。用Matlab對擷取之訊號進行差分與移動平均的訊號處理運算，顯示出擾動源的準確位置。
最後使用自製窄線寬光纖雷射取代φ-OTDR系統中的商用窄線寬光纖雷射進行測試。測試結果成功觀察到4.6km的待測光纖距離，但目前仍無法確定擾動源的位置，透過訊號處理無法濾除雜訊。推斷此結果為光源的穩定性導致，只要更進一步穩定雷射，即可成功使用自製窄線寬雷射進行φ-OTDR系統感測。

This paper aims to investigate the enhancement of narrow-width optical fiber laser and extension of the φ-OTDR system architecture in long-range vibration sensing experiment. We separately take a deep look into the internal components of the framework and their roles in the architecture. The selected narrow-width optical fiber laser in our experiment has increased in the power and further reduced the line width for the purpose of improving the laser stability. Comparing to former related research, the research result shows that the laser power has increased from 2.816mW to 56.3mW, an increase of nearly 20 times the power, and the line width has been reduced from 4.176kHz to 1.335kHz, which provides sufficient evidence to prove the enhancement in stability.
For the experimental factors in φ-OTDR system, the effective sensor distance is extended from 4.6 km to 10.1 km. Also, the construction of the framework and the impulse duplicated rate setting is optimized for strictly controlling the power rate of the framework, which make the φ-OTDR system sensor the simulating source of vibration 10.1 km away with 10 meters of spatial resolution and 4.9 dB SNR. For determining the accurate position of source of vibration, we apply difference and moving average for signal processing.
Lastly, we apply the selected narrow-width optical fiber laser as alternatives of commercial narrow-width optical fiber laser. The result indicates a successful observation of pre-test optical fiber distance at 4.6km, while the accurate vibration position remains unknown, and the signal processing is unable to effectively filter out the noise signal. As a result, we conclude the core reason causing this phenomenon depends on the stability of the light source. Further speaking, with a stabler source of laser, the φ-OTDR system sensor with selected narrow-width optical fiber laser can be conduct successfully.

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