以半導體光放大器為基礎的次載波塞取多工器在雙匯流排數位系統上的應用

Abstract

在本論文裡,我們回顧了半導體光放大器 (Semiconductor Optical Amplifier) 有關放大,接收與調變的最新研究工作.我們提出了以半導體 光放大器為基本元件的塞取多工器 (Add-drop Multiplexer),這種塞取多 工器可以省去光-電,電-光的轉換以減少光學元件的數目,進而取代傳統的 塞取多工器,這種塞取多工器也不需要因位元傳輸率 (Bit Rate) 的增加 而被更換.半導體光放大器做為次載波多工(Subcarrier Multiplexed) 系 統裡的塞取多工器實驗已被進行,在此實驗裡,兩個100 Mb/s的二元相移 鍵 (BPSK) 頻道在50公里長的光纖被傳送,包括放大,接收,調變三種功能 的錯誤率 (Error Rate) 皆能同時低於1e-9,塞取多工器的串接數目限制 也已經被討論,純粹由塞取多工器的串接而造成的非線性失真 (Nonlinear Distortion) 限制了串接的數目不能超過15級,這些非線性失 真主要是來自二階交互調變 (Second Order Intermodulation). In this thesis, we have reviewed state-of-the-art works regarding SOA's characteristics of three functions including amplification, detection, and modulation. We have proposed SOA- based ADM's that can minimize the number of optical components and can replace conventional ADM's which include the O/E and E/ O conversion. Our proposed SOA-based ADM is also bit-rate independent. The use of SOA as an SCM-ADM has been experimentally demonstrated in a 50 km link with two BPSK channels at 100 Mb/s. The BER's of three functions can be below 1e-9 all at the same time. System limitations on increasing the cascaded SCM-ADM's have been studied. The nonlinear distortions due to SOA concatenation may limit the number of cascades to less 15. These nonlinear distortions is mainly from the second order intermodulation.