华中科技大学光学与电子信息学院下一代互联网接入系统国家工程实验室, 湖北 武汉 430074
面对100 Gb/s光纤传输系统性能监测需求，自主研制完成高速线性光采样模拟前端。其内部由1个被动锁模光纤激光器产生脉宽为2 ps、重复频率为96.25 MHz 的采样光脉冲，待测偏振复用四相移键控(PDM-QPSK)信号和采样光脉冲进入光混频器后完成偏振相位分集探测，利用模拟带宽为400 MHz的平衡探测器完成光电转换后，将4路模拟信号传入主机进行数字化处理，获得高速光信号时域分析结果。通过优化设计，实现被动锁模光纤激光器的脉冲功率、中心波长、重复频率稳定输出。利用商用128 Gb/s PDM-QPSK 信号对工程样机和安捷伦调制信号分析仪N4391A 展开对比测试，测试结果表明工程样机可获得相同的时域参数分析结果。
光纤光学 全光采样 被动锁模光纤激光器 光纤通信 复杂调制码型
太原理工大学物理与光电工程学院, 新型传感器与智能控制教育部重点实验室， 山西 太原 030024
针对混沌光相干性差以及偏振态随机起伏的问题，提出了一种基于高非线性光纤中的四波混频效应对混沌激光偏振不敏感的采样方案，并通过数值的方法对波长为1550 nm，功率范围为0~10 mW的混沌光进行了采样。经研究发现，当抽运光功率为2 W，波长为1557 nm，光纤长度取60 m时，可使四波混频采样达到最佳。采用上述参数，数值实现了对混沌光的偏振不敏感采样，采样速率为5 GHz，采样的同时也起到了光放大的作用，增益系数约为10.8 dB。该结果可为实验上进一步实现混沌光的四波混频采样提供一定的理论依据。
激光光学 混沌激光 全光采样 四波混频 非线性光纤
Author Affiliations
Abstract
State Key Laboratory on Integrated Optoelectronics, Tsinghua National Laboratory for Information Science and Technology (TNList), Department of Electronic Engineering, Tsinghua University, Beijing 100084, China
The performance of a novel all-optical sampling orthogonal frequency division multiplexing (OFDM) system is proposed and analyzed. Time delays and phase shifters are used to realize all optical forward/inverse discrete Fourier transform (DFT/IDFT). Different system configurations are tested and analyzed to optimize the performance, including the system capacity, modulation formats, DFT/IDFT constructions, and the width of the sample pulse. The 50- and 100-Gb/s real-time all-optical sampling (AOS) OFDM systems are investigated. All results are analyzed, and useful suggestions are offered for future high-speed applications.
全光采样正交频分复用 超短光脉冲 循环后缀 060.2330 Fiber optics communications 060.4230 Multiplexing 070.2025 Discrete optical signal processing Chinese Optics Letters
2011, 9(1): 010603
全光采样实验中选用飞秒光纤激光器作为采样脉冲源, 用性能稳定的976 nm激光器作为抽运光源，利用非线性偏振旋转效应等效可饱和吸收体作为锁模器件，通过调节全光纤在线偏振控制器实现了自由运转被动锁模的掺铒环形腔飞秒光纤激光器，在抽运功率为176 mW时，激光器输出脉冲的重复频率为29.69 MHz，光谱谱宽16.8 nm,输出脉冲的平均功率可达8.1 mW。该激光器简单稳定, 其全光纤环形腔结构更有利于小型化，方便使用。
激光器 全光采样 飞秒脉冲 全光纤环形腔 非线性偏振旋转 被动锁模掺铒光纤激光器 光学学报
2010, 30(s1): s100307
Author Affiliations
Abstract
State Key Laboratory on Integrated Optoelectronics, Tsinghua National Laboratory for Information Science and Technology, Department of Electronic Engineering, Tsinghua University, Beijing 100084, China
A phase pre-emphasis technique used in an all-optical sampling orthogonal frequency division multiplexing (AOS-OFDM) system is proposed and demonstrated. With the application of this technique, 50-Gb/s AOS-OFDM data are successfully transmitted over 20-km uncompensated single-mode fiber (SMF) with real-time direct-detection. The constructive interference effect between symbols is decreased with this technique.
全光采样正交频分复用 相位预加重 实时 060.2330 Fiber optics communications 060.4230 Multiplexing Chinese Optics Letters
2010, 8(9): 871
Author Affiliations
Abstract
1 State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an 710068, China
2 Graduate University of Chinese Academy of Sciences, Beijing 100049, China
3 Department of Electrical, Computer and Communications Engineering, London South Bank University, London SE1 0AA, UK
An asynchronous optical sampling scheme based on four-wave mixing (FWM) in highly nonlinear fiber (HNLF) is experimentally demonstrated. Based on this scheme, 10-GHz input pulse train with 1.8-ps pulse width is successfully sampled in 100-m HNLF. A single pulse at 10 GHz with 2.3-ps pulse width is rebuilt by using a 50-MHz frequency tunable free-running fiber laser as the sampling pulse source (SPS). 40-GHz pulse train is used as the input signal. The rebuilt waveforms, together with the low-jitter eye diagram, are also presented.
全光采样 四波混频 高度非线性光纤 060.7140 Ultrafast processes in fibers 060.4370 Nonlinear optics, fibers 060.2360 Fiber optics links and subsystems 060.2330 Fiber optics communications Chinese Optics Letters
2010, 8(7): 630
电子科技大学光电信息学院，宽带光纤传输与通信教育部重点实验室，四川 成都 610054
利用半导体光放大器非线性偏振旋转效应实现全光采样具有采样速度高、输入抽运功率小的优点，为高速全光模数转换提供了可能途径。提出了半导体光放大器全光采样线性度和转换效率的表征方法，该方法利用传输曲线的多项式拟合函数表征采样系统，通过多项式的余弦代换和级数展开，得到全光采样线性度和转换效率与多项式系数的解析关系，从多项式系数直接计算线性度和转换效率。该方法无需复杂的傅里叶变换运算，其计算结果与傅里叶频谱分析结果吻合，可用于全光采样线性度和转换效率的精确表征，还可以拓展用于信号调制的非线性失真分析。
信号处理 全光采样 半导体光放大器 非线性失真 线性度
Author Affiliations
Abstract
Department of Opto-Electronic Engineering, Beijing Institute of Technology, Beijing 100081
The robustness of the software-synchronized all-optical sampling for optical performance monitoring is estimated for 10-Gb/s fiber communication systems. It reveals that the software-synchronized algorithm is sensitive to the signal degradation caused by chromatic dispersion and nonlinearity in optical fibers. The influence of timing jitter and amplitude fluctuation of the sampling pulses is also investigated. It is found that stringent requirements are imposed on the quality of the sampling pulse and the tolerance of 1-dB Q penalty is measured. Considering the practically available optical sampling pulse sources, the results indicate that the amplitude fluctuation of the sampling pulses has the dominant impacts on the software-synchronized method.
全光采样 光性能监测 色散 非线性 时间抖动 眼图 060.0060 Fiber optics and optical communications 060.2400 Fiber properties 070.4560 Data processing by optical means Chinese Optics Letters
2009, 7(3): 03194
