基于半导体光放大器的全光采样基础研究

【作者】 毛晶磊；

【导师】 刘永；

【作者基本信息】 电子科技大学 ， 光学工程， 2011， 硕士

【摘要】 未来高速光通信网络单通道的传输速率将超过100Gbit/s,这就需要对光信号进行灵敏、高速地检测。传统的方法是使用高速光电探测器和高速示波器进行检测,但是这种方法由于光电转换的瓶颈,其精确检测数据的速率只能达到40Gbit/s。另一个方案就是采用全光采样的方法,采样的脉冲在光域内直接对模拟光信号进行采样,避免了光电之间的转换,并且采样过程中数据格式是透明的,其潜在的采样速率也远大于电采样速率。本论文主要从以下三个方面进行课题的研究。在广泛查阅国内外文献的基础上,综述了目前实现的各种全光采样方案及其基本原理,对比各方案的优缺点。利用光纤、半导体光放大器以及各种非线性光学晶体的非线性效应实现全光采样是目前国际学术上的主流方向。半导体光放大器具有体积小、非线性系数大、交换光功率低、利于光子集成等优点逐渐成为研究的热点。利用半导体光放大器可以实现交叉相位调制、交叉增益调制、四波混频、差频产生和非线性偏振旋转等多种非线性效应。本论文将对这几种非线性效应的基本原理及其全光采样机制进行详细的介绍。本论文分别基于半导体光放大器交叉增益调制效应和非线性偏振旋转效应搭建全光采样实验系统。其中对基于交叉增益调制效应进行了静态和动态响应的测试,发现其响应效果并不理想而且存在输出信号与输入信号反向的现象,而基于非线性偏振旋转的全光采样系统实现了40GHz的光脉冲对2.5GHz模拟光信号的全光采样,采样出的信号的包络与泵浦光信号非常接近,说明采样的线性度良好,采样速率也达到40Gbit/s,这种方案都具有结构简单,可实现光子集成的优点,有成为未来高速全光采样方案的潜力。更多还原

【Abstract】 In the future, the single channel transmission speed of high-speed optical communication network can reach 100Gbit/s, which require to detect optical signal sensitively and high-speed. The traditional method of characterizing high-speed optical signals used a fast photodetector in conjunction with a high-speed oscilloscope. However, this method is limited by the electronic bottleneck; the precise detecting data rate can only achieve 40Gbit/s. Another method is all-optical sampling scheme, the sample pulse sample the analog optical signal directly, avoided opto-electronic conversion, and data format is transparent in the sapling process, its potential sampling rate also far outweigh the electricity sampling rate. The thesis research the project mainly from the following three aspects.Based on consulting the domestic and foreign literature, review the present realized all-optical sampling schemes and their basic principle, and contrast different schemes. Utilizing the nonlinearity based on fiber、semiconductor optical amplifier and various nonlinear optcail cystal to achive all-optical sampling is mainstream direction in currently international academic.Semiconductor optIcal amplifier(SOA) gradually becomes research hotspot due to their features such as compact、large nonlinearity coefficient、low switch power、campatib;e with photonic intergrated. Using semiconductor optical amplifier, some nonlinear effects such as cross-phase modulation(XPM)、cross-gain modulation(XGM)、four-wave mixing(FWM)、difference frequcncy generation(DFG) and nonlinear polarization roation(NPR) are achieved. Basic principle and all-optical sampling mechanism of those nonlinear effects are introduced in detail in this paper.All-optical sampling system based on XGM and NPR of SOA is build. its dynamic responsethe is tested, the result is not very ideal, and the output signal is reverse comparied with input signal, scheme based on NPR-SOA, 40GHz optical pulse is used to sample the 2.5GHz anolog optical signal. The envelop of sampled signal is very close to the sharp of pump light, so the sampling linearity is good, and the sampling rate is 40Gbit/s, This scheme has simple structure and allows photonic intergrated, is potential for ultra high speed sampling.更多还原