高速Cameralink视频信号的光纤传输系统设计

针对目前常用的Cameralink视频信号的光纤传输方案系统结构过于复杂的问题,提出一种基于MAX9249/MAX9268的Cameralink视频信号的光纤传输方案。在发送端利用MAX9249实现Cameralink视频信号解串行化、编码、串行化,得到光模块驱动信号CML;在接收端利用MAX9268实现CML信号解串行化、解码、串行化,得到Cameralink视频信号,并对光收发模块的设计与选型作了详细阐述。用示波器抓取发送端和接收端高速串行信号的眼图,结果比较清晰,眼睛张开度大,发送端的Q因子为24.46,满足发送端大于12的要求,接收端Q因子为8.13,满足接收端大于6的要求。计算机采集的实时画面,经过10 min传输无明显可视的像素噪点,验证了该传输方案的可行性和有效性。     

Ultra-broadband OFDM signal generation for 1-Tb/s super-channel coherent optical OFDM transmission

A 320.6-GHz multi-band optical OFDM signal generation scheme consisting of continuous 4,104 subcarriers is demonstrated for 1-Tb/s coherent optical OFDM (CO-OFDM) transmission. The 36 uncorrelated orthogonal bands are generated using a recirculating frequency shifter (RFS) with single laser by adjusting the loop delay of RFS to be an integer multiple of OFDM symbol period. The principle and performance of this generation scheme is studied theoretically and experimentally. The 1-Tb/s CO-OFDM signal is successfully received after 600-km SSMF fiber transmission without any dispersion compensation.     

高速OCDM系统中的全光阈值技术分析

分析了高速OCDM系统中基于非线性光学环境(NOLM)和非线性放大(NALM)环境的全光阈值技术。考虑了NOLM环境输入脉冲峰值功率对其阈值判决功能的影响,数值模拟了由高非线性光纤构成的NOLM和NALM环境的脉冲整形和旁瓣抑制功能,并和实验结果进行了比较。结果表明基于NOLM和NALM环境的全光阈值技术都能有效地抑制40 Gbit/s的OCDM系统中的干扰噪声,最优的NOLM环境的脉冲峰值输入功率为2 W,而NALM环境只需要mW量级的脉冲峰值输入功率即能够更好地抑制干扰噪声。     

高速光脉冲的测量方法

综述了目前国际上公认的测量高速光脉冲的几种方法,主要包括电光条纹相机（SC）、快速脉冲取样、二次谐波产生（SHG）、频率分辨光学门（FROG）以及光谱相位干涉直接电场重建（SPIDER）等。详细地阐述和分析了这些方法的原理、特点、适用范围以及它们的研究现状。     

高速光脉冲的测量方法

 综述了目前国际上公认的测量高速光脉冲的几种方法，主要包括电光条纹相机（SC）、快速脉冲取样、二次谐波产生（SHG）、频率分辨光学门（FROG）以及光谱相位干涉直接电场重建（SPIDER）等。详细地阐述和分析了这些方法的原理、特点、适用范围以及它们的研究现状。     

高速数据传输控制系统的设计

介绍了一种光盘数据高速传输控制系统。该系统相对计算机独立工作,可以方便灵活地组成各种数据传输控制系统,避免了计算机主机系统的介入,大大缩小了控制系统的复杂程度,避免了总线对连接设备个数的限制。使用16倍速DVD ROM,应用PIOMode4协议,在理论上该系统可以达到16 6Mbit/s的最高猝发传输速度。系统中央处理器采用单片机系统,通过内部编程,可以适应于不同的使用场合。输出端口使用数据缓冲器,以保证数据高速连续输出。     

用于快速人脸识别的光学协处理器

设计了一种用于快速人脸识别的光学协处理器。提出正负图像组合编码方法，一步实现了通常需要三步的数学形态学击中击不中变换，提高了识别速度。改进传统的识别判据，改善了识别效果。采用一个液晶投影板同时显示待识别图像和参考图像，简化了结构。给出了实验结果。     

Heterodyne receiver PICs as the first monolithically integrated tunable receivers for OFDM system applications

The state of the art in the fabrication of heterodyne receiver photonic integrated circuits (PICs) is described and in particular the results and experiences of the first fabrication of polarization-insensitive heterodyne receiver PICs are emphasized. The fabrication is based on a versatile integration concept with the potential also to fabricate other PIC architectures with different functionalities by only a single fabrication process.     

基于LabVIEW的光纤线路光功率信号实时采集系统

 为实时获取光纤内光功率信号,基于LabVIEW虚拟仪器编程语言,采用USB总线技术,结合光接收机和NI数据采集卡USB M6251构成的硬件平台设计了新型的高速采集系统。该系统克服以往光功率信号采集系统采样率低、单通道显示、界面交互能力弱、便携性差等缺点,实现了采样参数可控的双通道实时采集、显示、保存光功率信号等功能。该系统开发效率高,并通过实验证明其具有良好的人机交互能力,可靠性高,实用性强,能为各类光纤通信系统提供光功率信号监测功能。     

用于高速数据通信的梯度塑料光纤

概述了梯度塑料光纤的开发历史和现状。从应用于高速数据通信的角度 ,介绍了聚甲基丙烯酸甲酯(PMMA)、全氘化和全氟化梯度塑料光纤的损耗、带宽、稳定性和寿命。详细介绍了梯度塑料光纤的损耗光谱和损耗机制 ,介绍了制作梯度塑料光纤的界面凝胶聚合技术和两种扩散法 ,分析了梯度塑料光纤的制作方法同折射率剖面和带宽的关系 ,讨论了梯度塑料光纤的稳定性同掺杂物质的关系。同时介绍了高稳定性梯度塑料光纤的研究进展及今后的发展动向     

Optimization of pilot interval design in direct-detected optical OFDM system

The direct-detected optical OFDM (DDO-OFDM) system in frequency-selective fading fiber channel with three different types of pilot interval design has been experimentally investigated. In these schemes, the 2.28 Gbit/s QPSK-OFDM signal is transmitted over 100 km fiber in the system. The experiment results show the scheme with sparse pilot as frequency increasing shows the best performance for DDO-OFDM system.     

A novel optical burst switching architecture for high speed networks

A novel optical burst switching （OBS） high speed network architecture has been proposed. To verify its feasibility and evaluate its performance, just-enough-time （JET） signaling has been considered as a high performance protocol. In the proposed architecture, to avoid burst losses, firstly, a short-prior- confirmation-packet （SPCP） is sent over the control channel that simulates the events that the actual packet will experience. Once SPCP detects a drop at any of the intermediate nodes, the actual packet is not sent but the process repeats. In order to increase network utilization, cost effectiveness and to overcome some limitations of conventional OBS, inherent codes （e.g., orthogonal optical codes （OOC））, which are codified only in intensity, has been used. Through simulations, it shows that a decrease in burst loss probability, cost effectiveness and a gain in processing time are obtained when optical label processing is used as compared with electronic processing.     

高密度光学头中力矩器的运动串扰分析与抑制

力矩器多维运动之间的串扰是影响其动态特性和光斑质量的关键因素。建立了力矩器的空间受力分布模型,提出了聚焦、循迹、倾斜三个方向串扰度的概念,用数值方法计算并分析了力矩器的运动串扰现象,得到了串扰度与力矩器结构参数的关系。分析结果表明,串扰度与永磁铁和聚焦线圈的结构参数密切相关,合理选择结构参数可有效降低串扰度,可提高力矩器的动态性能。     

用于激光测距的小F数接收光学系统设计

为解决远距离漫反射激光测距系统能量损耗严重问题,并提高测距系统的响应速度,设计了一种小探测靶面大通光孔径的接收镜头。以3组4片式Petzval结构作为接收镜头的初始原型,将孔径光阑前移放置在第一面,同时增大其孔径以提高接收效率,最后一片引入非球面,以减小球差并使系统小型化;靶面采用直径为75 μm的雪崩光电二极管探测器,保证响应速度小于45 ns。经过优化设计得到通光孔径为120 mm的接收镜头,F数为0.6,可用于远距离漫反射激光测距领域。     

A scheme of optical interconnection for super high speed parallel computer

An optical cross connection network which adopts coarse wavelength division multiplexing (CWDM) and data packet is introduced. It can be used to realize communication between multi-CPU and multi-MEM in parallel computing system. It provides an effective way to upgrade the capability of parallel computer by combining optical wavelength division multiplexing (WDM) and data packet switching technology. CWDM used in network construction, optical cross connection (OXC) based on optical switch arrays, and data packet format used in network construction were analyzed. We have also done the optimizing analysis of the number of optical switches needed in different scales of network in this paper. The architecture of the optical interconnection for 8 wavelength channels and 128 bits parallel transmission has been researched. Finally, a parallel transmission system with 4 nodes, 8 channels per node, has been designed.     

Application of Turbo codes in optical OFDM multimode fiber communication system

In this paper, Turbo Code is proposed in optical OFDM multimode fiber communication system in order to decrease the bit error rate (BER) of the system, which is mainly affected by the deep nulls of the magnitude response of multimode fiber in the high frequency region (above 3 dB). A simulation system in SIMULINK is established. Based on the system, the BER of the system with Turbo Code is compare to the systems with another two typical coding schemes including convolutional code (CC) and serially concatenated code (SCC) which uses a concatenation of convolutional and RS codes when transmitting 10 Gbps data over various length multimode fibers. Different transmitting rate is also considered. The results show that Turbo coded system has a lower BER than the other two systems and the Turbo coded system can transmit 10 Gbps data to the distance of 300 m with BER below 1e−6.     

跟踪通信一体化接收光学系统设计

针对机载平台相对位姿变化快、机载设备日趋小型化轻量化等特点,基于大视场凝视扫描的方式,提出一种高帧频CMOS捕获、FSM调节跟踪、APD通信的同轴双光路跟踪通信一体化接收光学系统。介绍了系统的工作原理和方案;设计了一套验证系统,并对该系统的跟踪、瞄准性能进行了优化设计和分析。跟踪光路视场达到±175 mrad,90%能量光斑直径小于10 μm;通信光路视场达到±13 mrad,RMS直径小于3.5 μm。考虑到机载应用的特殊性,进一步分析了该系统杂散光特性和公差影响。分析结果表明:该方案同时满足高概率捕获、高精度跟踪、瞄准以及小型化的要求,对于机载激光通信具有一定借鉴意义。     

An improved least square channel estimation algorithm for coherent optical OFDM system

This paper presents an improved processing added to conventional least square (LS) channel estimation to modify its performance for coherent optical orthogonal frequency division multiplexing (CO-OFDM) system. By testing selected limitation factors of the existing algorithms, the influence of our improved algorithm to the performance of CO-OFDM system were studied and compared with other published algorithms. The simulation results of the study demonstrated that the proposed approaches achieved better channel estimation performance and are considered as a more appropriate alternative for CO-OFDM system with the tradeoff between complexity and performance.     

电磁干扰下时间分辨测量系统信号外触发技术

在实验的基础上给出了束参数时间分辨测量系统的实验布局和特点,分析高压电磁干扰对直线感应加速器中时间分辨测量系统外触发性能的影响和变化规律;进一步探讨系统高压电磁干扰后的抑制措施。针对电磁空间干扰情况,主要通过采用光纤传输控制信号的措施,能很好地传输窄脉冲,信号延时抖动小于2 ns,达到了高速信号的可靠传输要求,采用嵌入式控制器既解决了抗电磁干扰的要求,也满足了束参数时间分辨测量系统的使用要求。