由於資訊的發展迅速,有線電視系統除了傳送傳統的電視節目外,也開始提供許多加值服務如網路、多媒體、互動電視、電話和VOD 等雙向服務,也因為要提供許多資訊,使有線電視系統的頻寬開始有不足的現象,因此有線電視系統業者,開始著手建設光纖網路以因應未來需求。 由於目前光纖的各項傳輸設備的較為昂貴,因此本論文將致力於將用於客戶端的光接收放大器單價壓低,以取得有利的利基,研究中我們有別於一般購買市售光接收模組的設計方式,改為自行設計電路以降低成本,並利用實作驗證方式達到客戶對成本與規格的要求。 文中主要的規格驗證包括輸出準位,載波合成二次拍差,載波合成三次拍差,載波雜訊比,輸出端反射損失與訊號平坦度。經量測其各項參數均可達到客戶要求,但有些量測數據較為接近規格,因此仍有改善空間。
Due to the fast developing of information technologies, CATV systems providenot only traditional cable program, but also additional services such as networking,mmultimedia, interactive TV, telephone communication, and VOD etc. The frequencymrange of CATV systems have been overwhelming. Therefore, CATV companies havembuilt optical networks in the last couple of years for future demand. Because optical transmission equipments are more expensive, this study ismfocused on implementing a low cost optical amplifier. The design is different frommregular optical receive module in the market. Low cost components are employed formcircuit to meet customer’s request. The specifications are also tested in the laboratory. The specification includes output level, CSO, CTB, C/N, output return loss, andmsignal response. All parameters are fulfilled customer’s requirements, However, somemparameters that are marginal with respect to the specification need further improvement .