(西南交通大學　1.信息科學與技術學院；2. 光通信與光器件實驗室，四川　成都 610031)
摘? 要：以Santec公司OVA-650可變光衰減模塊為設計對象，設計制作用戶可控制數字光衰減器。分析OVA-650的衰減原理，建立測試系統, 確定步進電機移動步數與衰減量之間的關系。測試OVA-650內部衰減量與反饋電壓之間的對應關系并建立衰減量與電壓的對換表，采用Matlab進行數值分析及曲線擬合，得到衰減量與電壓關系的真實曲線，建立對應關系。建立用戶控制系統，鍵盤輸入用戶想得到的衰減量。本設計采用二相八拍控制步進電機，選擇12位模數轉換芯片MAX197,并采用自適應環路算法，精確定位到鍵盤輸入的衰減量，可控制范圍為0～35dB，整個系統誤差控制在±0.1dB以內，液晶顯示到0.01dB。
關鍵詞：可變光衰減器；OVA-650；步進電機；
中圖分類號：TN914.52??? 文獻標識碼：A
Based on the filter type variable optical attenuator test and control design
Qiao Feng1， Luo Bin1,2，Pan Wei1,2
(1.School of Information Science & Technology; 2.Optical Communication And Optical Devices Lab
Southwest Jiaotong University, Chengdu 610031，China)
Abstract: Take OVA-650(Santec corporation) invariable optical attenuator module as the design object, this design establishes user control system.By principle, the establishment of test systems to stepper motor moves and the relationship between the attenuation. OVA-650 testing of internal decay and feedback, pressure and the corresponding relationship between the establishment the voltage and attenuation on the table for using Matlab numerical analysis and curve fitting, and get the real curve, the establishment of corresponding relations. The establishment of user control system, keyboard users want attenuation. This design uses two-phase 8 deadbeat control stepper motor, select 12 analog-digital conversion MAX197 chip, and adaptive loop algorithms, accurate positioning of the keyboard input attenuation Volume control range of 0～35 dB, in the whole system error control within ± 0.1dB, and liquid crystal displays to 0.01 dB.
Key words: Variable Optical Attenuator; OVA-650; stepper motor;
可變光衰減器(VOA)是光通信系統中重要的光器件之一,其主要功能是完成光信號的功率限制與多路光信號的功率均衡,在光纖網絡和系統中起到功率管理的作用,用來使整個網絡中的功率電平保持一定,使光通信網絡更加智能化且更具靈活性。VOA對DWDM光纖網的重要意義在于: VOA能夠在光學層(Optical Domain)實現對光網絡的全面遠程控制[1]。到目前為止，光衰減器已形成了固定式、步進可調式、連續可調式、及智能光衰減器四種系列。按光衰減器的工作原理可分為位移型光衰減器、直接鍍膜型光衰減器、衰減片型光衰減器、液晶型光衰減器。