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利用时空混沌同步进行数字加密通信

物理学报 2001年第10期50卷 1856-1861页

作者：匡锦瑜邓昆黄荣怀北京师范大学电子学系北京100875

提出一种利用时空混沌同步的计算机网络数字加密通信方案 ,并用软件实现了语音双工实时密码通信 .在该方案中 ,收、发端两个单向耦合映射格点 (OCOML)系统被同一混沌信号所驱动而达到同步 ,其时空混沌输出信号分别用作加密和解密的密钥... 详细信息

提出一种利用时空混沌同步的计算机网络数字加密通信方案 ,并用软件实现了语音双工实时密码通信 .在该方案中 ,收、发端两个单向耦合映射格点 (OCOML)系统被同一混沌信号所驱动而达到同步 ,其时空混沌输出信号分别用作加密和解密的密钥序列 ,OCOML的耦合参数为系统的主密钥 .系统的主要优点是传输效率高 ,便于用软件实现实时通信 ,且通信的安全性获得了改善 .

关键词：数字加密通信时空混沌同步密码系统传输效率通信安全

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Asymmetric Nonlinear Optical Loop Mirror for All Optical Clock Extraction in Self-clocked Optical Transparent OTDM Network

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Chinese Journal of Lasers 1999年第3期 40-45页

作者： ZHOU Xiang YE Peida SHI H. X. WANG L. J. LIN J. T. (Optical Communication R and D Center, P.O.Box 57 (B962), Beijing University of Posts and Telecommunications, Beijing 100876, China) received Aug. 11, 1998 revised manuscript received Oct. 26,

１ＩｎｔｒｏｄｕｃｔｉｏｎＡｓａｅｆｅｃｔｉｖｅｗａｙｔｏｔａｋｅｆｕｌａｄｖａｎｔａｇｅｓｏｆｔｈｅｂａｎｄｗｉｄｔｈｏｆｔｈｅｆｉｂｅｒ，ｏｐｔｉｃａｌｔｉｍｅｄｉｖｉｓｉｏｎｍｕｌｔｉｐｌｅｘｉｎｇ（ＯＴＤＭ）... 详细信息

１ＩｎｔｒｏｄｕｃｔｉｏｎＡｓａｅｆｅｃｔｉｖｅｗａｙｔｏｔａｋｅｆｕｌａｄｖａｎｔａｇｅｓｏｆｔｈｅｂａｎｄｗｉｄｔｈｏｆｔｈｅｆｉｂｅｒ，ｏｐｔｉｃａｌｔｉｍｅｄｉｖｉｓｉｏｎｍｕｌｔｉｐｌｅｘｉｎｇ（ＯＴＤＭ）ｔｅｃｈｎｏｌｏｇｙｈａｓｂｅｎｗ...

关键词： optical fiber communication clock extraction NOLM self clocked OTDM networks

Study on the Beam Quality of Uncoupled Laser Diode Arrays

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Chinese Journal of Lasers 2001年第4期 1-5页

作者： GAO Chunqing WEI Guanghui (Optical Engineering Department, Beijing Institute of Technology, Beijing 100081, China) received Oct. 13, 2000 revised manuscript received Dec. 27, 2000

The beam quality of uncoupled laser diode array is studied theoretically and experimentally. By calculating the second order moments of the beam emitted from the laser diode array, the dependence of the M 2 factor of the laser diode array on the M 2 factor of the single emitter, the ratio of the emitting region to the non emitting space, and the number of emitters, has been deduced. From the measurement of the beam propagation the M 2 factor of a laser diode bar is experimentally determined. The measured M 2 factor of the laser diode bar agrees with the theoretical prediction.

关键词： Laser diode array beam quality second order moments

Theoretical Analysis on the Simultaneous Operation of a Color-Center Laser and a -Switched Nd∶YAG Laser

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Chinese Journal of Lasers 2000年第5期 22-27页

作者： WU Xing DING Yongkui ZHANG Rui (College of Precision Instruments and Optoelectronics Engineering, Tianjin University,Tianjin 300072,China) received Oct. 13, 1999 revised manuscript received Dec. 27, 1999

The simultaneous operation for the Q switched Nd∶YAG laser at 1.06 and the tunable color center laser over 1.12～1.26 μm has been realized by using a LiF∶F - 2 color center crystal both as the Q switcher for the Nd∶YAG laser and as the active medium for the color center laser. The interaction of the two lasers has been analyzed and calculated with the rate equations. The pulse duration of YAG laser is compressed, in agreement with the experimental results.

关键词： Nd∶YAG laser color center crystal Q switch

Linewidth of Semiconductor-Optical Fiber Ring External Cavity Laser with Tunable Optical Fiber F-P Cavity

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Chinese Journal of Lasers 1998年第5期 7-11页

作者： YUAN Zongheng LIU Yongzhi (Department of Optoelectronic Tecnology, University of Electronic Science and Technology of China, Chengdu 610054, China) received Aug. 7, 1997 revised manuscript received Nov. 17, 1997

１ＩｎｔｒｏｄｕｃｔｉｏｎＮａｒｏｗｌｉｎｅｗｉｄｔｈｔｕｎａｂｌｅｓｉｎｇｌｅｆｒｅｑｕｅｎｃｙｓｅｍｉｃｏｎｄｕｃｔｏｒｌａｓｅｒｓａｒｅｎｅｄｆｏｒａｐｐｌｉｃａｔｉｏｎｓｉｎｃｏｈｅｒｅｎｔｃｏｍｍｕｎｉｃ... 详细信息

１ＩｎｔｒｏｄｕｃｔｉｏｎＮａｒｏｗｌｉｎｅｗｉｄｔｈｔｕｎａｂｌｅｓｉｎｇｌｅｆｒｅｑｕｅｎｃｙｓｅｍｉｃｏｎｄｕｃｔｏｒｌａｓｅｒｓａｒｅｎｅｄｆｏｒａｐｐｌｉｃａｔｉｏｎｓｉｎｃｏｈｅｒｅｎｔｃｏｍｍｕｎｉｃａｔｉｏｎ，ｃｏｈｅｒｅｎｔｄｅ...

关键词： semiconductor laser linewidth optical fiber F P cavity

The Study on the Performance of the Wavelength Conversion Based on a Tunable External Cavity Semiconductor Laser

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Chinese Journal of Lasers 2001年第1期 41-47页

作者： YE Yabin ZHANG Hanyi ZHENG Xiaoping DAI Wuju GUO Yili (Department of Electronic Engineering, Tsinghua University, Beijing 100084, China) received March 14, 2000 revised manuscript received May 15, 2000

In this paper, the performance of the wavelength conversion based on a tunable external cavity semiconductor laser (ECL) was studied. The static wavelength conversion was achieved in the tunable wavelength range of the ECL. The dynamic wavelength conversions of 155 Mb/s and 622 Mb/s nonreturn to zero (NRZ) signals were realized. The simulation of the ECL output characteristics using modified compound cavity rate equation shows that the higher bit rate wavelength conversion can be realized by increasing the relaxation oscillation frequency of the ECL. When the modulated bit rate is much lower than the relaxation oscillation frequency, under a fixed input signal power, there is an optimal bias current for the wavelength converter based on ECL.

关键词： Tunable external cavity semiconductor laser wavelength conversion relaxation oscillation

Wavelength Sweep Interferometry for Measuring the Refractive Index and Physical Thickness

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Chinese Journal of Lasers 2001年第4期 11-16页

作者： SONG Guiju WANG Xiangzhao FANG Zujie (Shanghai Institute of Optics and Fine Mechanics, The Chinese Academy of Sciences, Shanghai 201800, China) received Sep. 22, 2000 revised manuscript received Nov. 29, 2000

A method combining wavelength sweep interferometry with the Fourior transform technique to perform the separate measurements of the physical thickness and the refractive index is proposed. By converting the optical path difference of the interferometer to the beat frequency of the interference signal we realize the depth scanning without mechanical moving parts. The effect of specimen dispersion is avoided by using a narrow tuning laser diode. For demonstrating this method we measure the physical thickness and the refractive index of an x cut LiNbO 3, BK9 and BK7 glass, and the results consist with the reported values.

关键词： interfrometer physical thickness refractive index

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扫描近场红外显微镜光纤探针的腐蚀制法

物理学报 2001年第12期50卷 2322-2326页

作者：张立源李永贵王潜中国科学院高能物理研究所自由电子激光实验室北京100080

红外光探针是扫描近场红外显微镜 (SNIM)中的关键部件 ,由于探针的种类和材料不同 ,制作的方法也不同 .一般制作光纤探针有两种方法 ,即热拉伸法和化学腐蚀法 .这里叙述了一种化学腐蚀方法 ,介绍了怎么去除砷硒碲中红外光纤的聚酰胺表... 详细信息

红外光探针是扫描近场红外显微镜 (SNIM)中的关键部件 ,由于探针的种类和材料不同 ,制作的方法也不同 .一般制作光纤探针有两种方法 ,即热拉伸法和化学腐蚀法 .这里叙述了一种化学腐蚀方法 ,介绍了怎么去除砷硒碲中红外光纤的聚酰胺表层和硫化硒夹层 ,以及芯层腐蚀成针尖状的具体方法和过程 ,并对短锥针探针制法进行了探索 .最后用此探针在近场范围内探测了氮化镓样品的自由电子激光 (FEL)

关键词：扫描探针显微镜 SPM 近场红外扫描显微镜 SNIM 光纤探针腐蚀制作

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Optimal Design of a Distributed Optical Fiber Temperature Sensor system Based on Raman Back-scattering

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Chinese Journal of Lasers 2001年第1期 30-34页

作者： CHANG Cheng LI Zheng ZHOU Yinqing (Department of Electronics Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100083, China) received March 20, 2000 revised manuscript received May 22, 2000

The distributed optical fiber sensor system based on Raman back scattering has many advantages and gains more interests. However, the intensity of the back scattering light, especially the anti Stokes light is too weak to be detected without certain special arrangements. This paper presents three important principles for optimal design of the system after the optimal analysis of the center wavelength, the optimal design of the Raman filters and the cluster analysis of the LD’s spectrum. They are proved reasonable and useful to an actual system design.

关键词： Raman scattering optical fiber temperature sensor