網際網路(Internet)日益興盛,傳輸的容量也就越來越不敷使用,人們開始找尋更高、更快速的傳輸方式,可以大量資訊傳輸的光纖通信系統因此逐漸成為世界各國熱門的研究及發展論題。為了實現此目標,高密度波長多工網路儼然成為未來光纖通信傳輸系統的必然趨勢。高密度分波多工器為高密度分波多工網路的關鍵性元件,而擁有易於擴大波道數、封裝成本低、可積體化及適合大量生產等優點的陣列波導光柵(AWG)波長多工器,為未來達到多波道與窄頻道寬度需求最具發展潛力的元件。 本研究在於如何設計一個光纖通訊被動元件中的AWG分波多工器,並且以基本設計流程完成一個規格為 1×8頻道、200 GHz 的AWG分波多工器,最後使具有良好的元件分波性能。另外,在AWG的自由耦合區域的輸出端與接收端波導上加上錐形口設計(Taper),可使頻道訊號平坦化,並且控制溫度與偏振態對於訊號波長的影響,有效地容許波長漂移的誤差,其相鄰頻道間串音平均值約在-45dB 左右,插入損失約在2dB之內。另外,當AWG錐形口的寬度越大時,頻道寬度亦成線性的加大,最佳區域分配中錐形口波導每增加 1μm寬度,頻道寬度可增加0.0246nm、插入損失可降低0.3247dB。最後本研究提出利用多模態干涉觀念(Multimode Interference ; MMI ),配合錐形口結構AWG的新型結構,可以得到相鄰頻道間的串音干擾約 -44 dB、插入損失約 1.16 dB,其分波的性能較一般波導與錐形口波導的AWG為佳。此外,本文研究分析錐形口區域分配對系統的傳輸效率的評比,可以做為在製程上與成本上的參考依據。
With the growing prosperity of the internet network day by day , the transmission capacity has become insufficient to meet all the requirements of practical use. Therefore, people start looking for higher, faster transmission ways to increase the capacity of transmission. Under such circumstances, the research concerning optical fiber communication systems has gained increasingly interests. The dense wavelength division multiplexing (DWDM), the future trend of optical fiber communication systems, is a critical component to DWDM network systems, and the establishment of AWG, package easier and produced in a great number, is the sky element to multiply channels and narrow bandwidths. This paper is focus on designing AWG in optical fiber communication and building a basic design of 1×8 channels、200GHz AWG which have good performance. Adding taper structure in AWG I/O waveguide of free propagation range (FPR), the spectrum response becomes flat and the error of wavelength shift which is influenced by temperature and polarization is tolerated, the crosstalk of adjunct channels is -45 dB, insertion loss is 2 dB. As the width of taper is increased by 1μm, the width of spectrum response is also increased by 0.0246nm、the insertion loss of spectrum response is also decreased by 0.324dB. Finally, the performance of AWG will be better than classical one by using both multimode interference (MMI) and taper structure of AWG, the crosstalk of adjunct channels is -44dB, insertion loss is 1.16dB.The propagation effectiveness of taper structure can be a standard of fabrication and cost.