空间激光通信研究现状及发展趋势

综述了空间激光通信的技术优势,总结了国外主要空间激光通信系统运行计划和相应的参数指标,重点介绍了空间激光通信技术在美国、欧洲、日本的研究现状,给出了激光通信的关键技术。指出了未来的空间激光通信技术不仅会使通信速率越来越高,其通信模式也会从点对点单一通信模式向中继转发和构建空间激光通信网络方向发展。最后对我国空间激光通信技术的发展作了简要介绍。  

分布式计算机实时数据传输板的设计与实现

从军用光电系统实时数据传输的需求出发,提出了基于VxWorks实时操作系统PCI总线双机数据传输板的设计方案.经测试,数据传输速率达到94 MB/s,能够满足军用光电系统实时数据传输要求.  

Quantum Cryptography with Correlated Twin Laser Beams

The data transmission protocol using strongly correlated twin laser beams is proposed. The properties of the laser beam states are described in detail. The protocol is based on the strong correlation of photon numbers in both beams in each measurement. The protocol stability against eavesdropping attacks is analyzed.  

ISI and polarization switching in high bit rate optical fiber transmission systems

In the paper, there is investigated inter-symbol interference (ISI) in high bit rate optical transmission systems employing standard optical fibers with no dispersion compensation. Two types of systems are examined: a typical system with external light modulator and a system with additional polarization switching. The dependence of the optical path loss and horizontal eye pattern opening on the fiber length and input impulse shape is found for both the systems via computer simulation. The polarization switched system has better parameters for greater transmission distances (L > 70,***,100 km) whereas for smaller distances the parameters for both systems are comparable. The optimum impulse shape that minimizes ISI is also found.  

Missing modes in 1.3 μm InGaAsP/InP uncooled Fabry–Perot lasers and their effect on transmission performance

We report mode missing and modal instability of uncooled Fabry–Perot (FP) lasers for the temperature range from –45 to 85C and their effect on transmission performance. Using the time domain laser model (TDLM), mode missing has been modeled in FP lasers with structural defects in the active layer. Using this model, we have estimated eye opening penalty (EOP) due to missing modes up to 2.5 Gbps data rate. These simulation results suggest that FP lasers should have less than two missing modes for stable operation and high performance for optical data links.  

水声信道线性均衡的研究

本文在对LMS和稀疏权自适应均衡算法进行分析的基础上，将其引入到水声数据传输中，利用LMS算法对时不变信道和慢变信道进行了仿真实验；利用稀疏权自适应均衡算法对深海信道进行了仿真实验，并获得了仿真结果。  

基于单片机的课室人数智能监测与自助查询系统研究

研究了一种应用于课室在座人数实时监测的分布式自动化系统。该系统通过在课室安装一个以STC89C52单片机和YL-62红外线传感器为核心的人数进出信息反馈和处理模块,进行编码后经过CC1101无线数据发射模块将信息发送至连接PC机串口终端的接收模块,利用PC机进行解码和运算处理并最终显示在VB程序界面,从而达到远程监测与查询课室人数的目的。该系统结构简单,成本低廉,性能可靠,具有较大的应用前景。  

基于USB3.0的高速数据传输电路的设计

针对大容量数据记录器与外围计算机之间的数据通信时间长速度慢的问题,借助USB3.0接口良好的向后兼容性、易于使用性、可热插拔性、传输速度快等特点,设计了以FPGA为主控单元, DDR2 SDRAM作为高速大容量缓存,USB3.0接口作为与计算机进行数据通信接口的高速数据传输电路系统。采用外接I2C接口的EEPROM作为USB3.0接口芯片的启动方式；通过专用的线性稳压器为DDR2提供稳定的参考电压和吸收电流；最后详细介绍了USB3.0接口芯片的固件程序配置和FPGA控制模块的逻辑设计。实验测试结果表明,通过USB3.0接口该系统数据传输速度达到149.29M/S,且数据传输可靠。  

USB3.0接口在数据存储系统中的应用

USB3.0的传输速率最快可达5Gbps,因此,为实现大量数据的快速稳定传输,介绍了一种以FPGA为控制核心,DDR2 SDRAM为高速大容量缓存,USB3.0为记录器与计算机进行数据通信接口的高速数据传输系统,通过模块硬件电路及软件协议实现了数据的高可靠性稳定传输,解决了大容量记录器的数据传输速度瓶颈。经长期试验证明：该接口传输速度可稳定到达150M/s,且数据可靠无误,满足任务设计要求。  

Beam reception and data transmission performance analysis of optical taper used in a mobile wireless optical communication

Mobile wireless optical communication system was demonstrated experimentally by using a special solid coupling optical taper. The performance of special solid coupling optical taper and the data transmission performance with 240 Mbit/s were investigated on the rectilinear orbit between the mobile terminal and the fixed terminal. The experimental results shown that the scheme used in the mobile wireless optical communication system is reliable and quite simple, which could be widely used in future.