前置光放大器实验研究

Experimental Research of Optical Preamplifier

报道了在１４０Ｍｂ／Ｓ光通信端机上采用国产１．３μｍ低噪声半导体光放大器作为前置光放大器的研究结果。理论分析和实验表明，必须采用窄带光学滤波器滤除光放大器自发辐射引起的各种噪声。当光学滤波器为最佳带宽４ｎｍ，光放大器为最佳电流６５ｍＡ时（此时增益为１４ｄＢ），系统接收灵敏度改善５ｄＢ。前置光放大器噪声指数大约为３ｄＢ。

In this paper,we report the research results of optical preamplifier using 1. 3μm low noisesemiconductor laser amplifier before 140Mb/ s fibercommunication receiver.Theoretical analvsis andexperimental resuIts show that a narrow band optical filter is necessary to fiIt noise produced by spontaneousradiation in optical am plifier.When the optim um width band of optical fiIter is 4 nm and the optimumpumping current of optical amplifier is 65 mA(the gain is 14 dB) ,the receiver sensitivity is improved by5dB and the noise index of preamplifier is about 3 dB.