臺灣博碩士論文加值系統

本論文包含兩個主要研究部分：一是應用於光纖陀螺儀的寬頻摻鉺超螢光光纖光源之研究，另一是關於海下無人載具系統的光纖視訊傳輸技術之研究。在光纖陀螺儀用的寬頻光纖光源之研究中，我們探討與比較使用不同平坦化技術的摻鉺超螢光光纖光源，在前向雙路徑及後向雙路徑架構下的特性。為了使超螢光光纖光源能得到高輸出功率、寬譜線寬度以及穩定的平均波長，我們利用選擇最佳的摻鉺光纖長度與泵激功率之內在平坦化方式來完成；外在平坦化方式中，可選擇在摻鉺光纖後加入適當的摻釤光纖長度來達成，或在超螢光光纖光源的輸出端加上一個短週期的布拉格光纖光柵帶拒濾波器來獲得。我們從實驗結果中得知，當使用每一種平坦化方式時，不論在前向雙路徑或後向雙路徑架構下的超螢光光纖光源，其於輸出功率、譜線寬度和平均波長穩定度方面皆擁有很相似的特性。雖然使用內在平坦化技術的前向雙路徑和後向雙路徑架構下之超螢光光纖光源，其輸出功率會比較大；但它們也伴隨著大的光譜功率變動。前向雙路徑及後向雙路徑架構下的超螢光光纖光源，其使用短週期的布拉格光纖光柵帶拒濾波器時，可獲得一個具優秀光譜平坦度之較大的譜線寬度，及較好的平均波長穩定度。像這麼平坦的寬頻摻鉺超螢光光纖光源，是目前已知所有報告中最好。相反地，在前向雙路徑及後向雙路徑架構下的超螢光光纖光源，利用摻釤光纖當作光譜平坦器時，其對於所有特性上皆無任何助益。
在海下無人載具系統的光纖視訊傳輸技術之研究部分，我們已成功地探討了分波多工技術及次載波技術的可行性，利用這兩種多工技術可降低光纖光纜中的使用芯數，因此纜繩的直徑就可減小，也可使光旋轉接頭的芯數減少。這樣不只可降低系統成本，也增加絞盤操作時的方便性及提高未來系統的擴充性。在應用次載波技術的系統中，還可進一步減少光發射器及光接受器的使用個數。

This thesis includes two parts: the broadband erbium-doped superfluorescent fiber source (SFS) for fiber optic gyroscope (FOG), and the fiber-optic video transmission technique of remotely operated vehicle (ROV). For the study of SFS for FOG, we investigate and compare the characteristics of erbium-doped SFS using different flattening techniques in double-pass forward (DPF) and double-pass backward (DPB) configurations. The intrinsic flattening is to optimize the erbium-doped fiber (EDF) length and pump power for an SFS to obtain high output power, wide line-width, and stable mean wavelength. The extrinsic flattening methods include addition of an appropriate length of the samarium-doped fiber (SDF) or by adding a short-period fiber Bragg grating (FBG) notch filter at the output port of the SFS. Experimental results show that both DPF and DPB SFS's have similar features in output power, line-width, and mean wavelength stability for each of the flattening methods. Although the DPF and DPB SFS's with the intrinsic flattening technique have a larger output power, they accompanied with large spectral power variation. The DPF and DPB SFS's with short-period FBG notch filter can achieve a wider line-width with excellent spectral flatness and better mean wavelength stability. To the best of our knowledge, both the FBG-flattened DPF and DPB SFS's are the most flat, broadband erbium-doped SFS's ever reported. On the contrary, both DPF and DPB SFS's using the SDF as a spectral flattener have no benefits in all characteristics. For the study of fiber-optic video transmission technique for ROV, we have investigated the feasibility of both wavelength division multiplexing (WDM) and sub-carrier multiplexing (SCM) techniques for ROV fiber-optic transmission system. Both techniques can reduce the required fiber counts, and thus decrease the outside diameter of the used optical fiber cable. Furthermore, simplify the rotary fiber-optic connector. In consequence, both techniques not only lower down the system cost of ROV, and make the operation of winches more easily, but also offer the expandability of fiber-optic communication system. For the SCM technique, the number of required optical transmitters and receivers can be reduced again as compared with the WDM one.