本論文旨在優化一布里淵散射效應之分佈式光纖感測系統，主要優化項目包括空間解析度、量測距離、應力感測靈敏度與線性度。首先介紹分佈式光纖感測系統量測原理並定義重要參數，透過選取訊號調變強度，以及分析探測光強度與極化狀態之間的影響來改善空間解析度。在調變強度範圍100 mV至2000 mV中，發現1000 mV能使光源有最寬的3-dB頻寬為2.2 GHz與較高的光源功率-26.62 dBm，故找出1000 mV為較佳調變強度。利用光衰減器設置衰減值0 dB至4 dB，受極化影響的平均功率變動會由0.3575 ppm降低至0.2727 ppm，且發現在1 dB與2 dB時有較好的空間解析度，故選擇衰減2 dB使探測光達到較佳強度。接下來介紹實驗室自製可調式布拉格光纖光柵，探討其對系統探測光調制成單邊頻帶之效果與特性較佳光柵選取，並藉由光纖光柵同時具有反射特定波長並穿透其它波長的特性，設計出穿透型與反射型兩種調制架構。穿透型架構能夠使高頻旁帶與低頻旁帶光功率差達到4.65 dB，且相較於調制前之總功率損耗為0.6 dB；反射型架構能夠使高頻旁帶與低頻旁帶光功率差達到24.07 dB，而相較於調制前之總功率損耗為1.96 dB，故穿透型調制架構具有損耗較低的優勢，而反射型調制架構具有單邊頻帶調制效果較佳的優勢。最後將單邊頻帶調制架構應用於系統量測，利用原始架構量測53公尺距離並無法完整量測；加入穿透型調制後能成功量測到66公尺並有50公分空間解析度；加入反射型調制後能成功量測53公尺並有30公分空間解析度，但量測66公尺時因反射型架構衰減較多造成空間解析度較差。在光纖應力感測部分，給予軸向應力0 με至4500 με，每100 με紀錄一次，無單邊頻帶調制架構之靈敏度為2.617 MH/100με，線性度R^2為0.9436；加入穿透型調制之靈敏度提升為2.651 MH/100με，線性度R^2提升為0.954；加入反射型調制之靈敏度提升為2.777 MH/100με，線性度R^2提升為0.9599。

The aim of this thesis is to improve a distributed fiber sensing system based on Stimulated Brillouin scattering (SBS) effect. The improved characteristics consisted of the spatial resolution, sensing range, sensitivity, and linearity. First, the measuring principle was introduced and important parameters of distributed fiber sensing system were defined. The spatial resolution was affected by modulation amplitude, power intensity and polarization state of the laser. From 100 mV to 2000 mV modulation amplitude, we found that the widest 3-dB bandwidth of 2.2 GHz, and higher optical power of -26.63 dBm could be obtained when the modulation amplitude was set 1000 mV. As the attenuation value was increased from 0 to 4 dB, the polarization-dependent power variation decreased from 0.3573 ppm to 0.2727 ppm. We also find that attenuation value of 1 to 2 dB may result in better spatial resolution. Therefore, attenuation value of 2 dB was selected in this study. Then, the homemade tunable fiber Bragg grating using for obtaining single sideband modulation (SSB) was discussed. The transmission type (T-type) and reflection type (R-type) setups for SSB were designed and investigated. The difference of optical power between the upper sideband (USB) and lower sideband (LSB) was 4.65 dB by using T-type setup, and the difference may even increase to 24.07 dB by using R-type setup, respectively. The total power loss was 0.6 dB by using T-type setup and 1.96 dB by R-type setup, respectively. Therefore, T-type setup has lower loss while R-type setup has the advantage of better SSB modulation. Finally, two types of SSB modulation approaches were applied to system sensing measurement. We successfully achieved a fiber span of 66 m with 50 cm spatial resolution based on T-type setup, and a fiber span of 53 m with 30 cm spatial resolution based on R-type setup. For strain sensing, the strain was increased from 0 με to 4500 με in step of 100με. By using original setup with double sideband, the sensitivity and the linearity R^2 were 2.617 MH/100με and 0.9436, respectively. By using T-type setup, the sensitivity and the linearity R^2 were improved to 2.651 MH/100με and 0.954, respectively. By using R-type setup, the sensitivity and the linearity R^2 were improved to 2.777 MH/100με and 0.9599, respectively.

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