用光纖共振腔作全光學式光時脈復原之研製

Abstract

在本篇報告中, 一個應用於數位光纖通訊系統的濾波全光學式時脈回復 電路已被予實驗上之驗證. 使用一個光共振腔當一光濾波器, 它的FSR等 於輸入數位訊號的傳送速率, 其可將進入之數位訊號的line spectral component, 包含了傳送速率, 濾出而達到一全光學式的時脈回復電 路. 在實驗上已成功的從一227Mbs/s RZ 的數位訊號中, 粹取出其光 時脈訊號. 所用的光共振腔為兩個單模光纖耦合器熔接而成, 其Finess 主要決定於光纖耦合器的耦合係數及共振腔的光纖功率損耗, 經過細心的 熔接技術可使其Finess達到700以上, 在此濾波全光式時脈回復架構, 除 須要一光濾波器外, 尚須對其光模組做穩定控制, 包括外部調變器穩壓及 雷射穩頻, 實驗上 , 在調變器部分可將其光輸出功率變動控制在0.01dB 以下, 而雷射頻率則可相對穩在1MHz以下, 接著我們亦使用此光纖共振 腔當頻率鑑別器作半導體雷射穩頻實驗, 且成功的將其頻率相對穩在0.5 MHz以下並可在光纖共振腔內加一PZT微調此雷射的頻率, 最後我們亦探了 雷射線寬, 溫度和光極化方向對此系統的影響和所能達到的最高速率及 其改進方法. A filtering fiber-based all optical clock recovery circuit used for digital optical fiber communication system is in experiment. An optical clock synchronized to an incoming data stream is generated by extracting line spectral components in the data stream using an optical resonator whose free spectral range is equal to the incoming data bit rate. The principle of is demonstrated using a fiber ring type optical resonator at 227 The fiber ring type resonator is formed by fusing two fiber It's finess is mainly determined by the coupler coupling ratio the cavity round trip loss.By carefully fusing technique, the finess can exceed 700.Besides the optical carrier filter , the module stabilization control is also very important in this all clock recovery experiment setup. It includes the external DC bias stability and the laser frequency stabilization. In this experiment, the external modulator output power fluctuation is within 0.01dB, and laser frequency is relatively controlled 1MHz. This fiber resonator is also used as optical frequency inator to stabilize the semiconductor laser frequency. It is fully relatively locked within 0.5 MHz and can be tuned with a Finally, the laser linewidth , temperature, and polarization that influences this system and the maximum workable data bit rate is discussed.