中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
机构
采集方式
内容类型
发表日期
学科主题
筛选

浏览/检索结果: 共9条,第1-9条 帮助

条数/页: 排序方式:
基于Malaga湍流信道和Nakagami衰弱信道的选择合并混合FSO/RF系统的性能分析 期刊论文  OAI收割
激光与光电子学进展, 2021, 卷号: 58
作者:  
吴琰;  戴聪明;  赵凤美;  魏合理
  |  收藏  |  浏览/下载:11/0  |  提交时间:2023/11/10
Heavy-ion and pulsed-laser single event effects in 130-nm CMOS-based thin/thick gate oxide anti-fuse PROMs 期刊论文  OAI收割
NUCLEAR SCIENCE AND TECHNIQUES, 2019, 卷号: 30, 期号: 5, 页码: 11
作者:  
Zhao, Pei-Xiong;  Geng, Chao;  Zhang, Zhan-Gang;  Liu, Jie;  Li, Xiao-Yuan
  |  收藏  |  浏览/下载:69/0  |  提交时间:2019/11/10
Demonstration of horizontal free-space laser communication with the effect of the bandwidth of adaptive optics system 期刊论文  OAI收割
Optics Communications, 2019, 卷号: 431, 页码: 167-173
作者:  
R.Wang;  Y.K.Wang;  C.B.Jin;  X.H.Yin;  S.X.Wang
  |  收藏  |  浏览/下载:21/0  |  提交时间:2020/08/24
Communication synchronization in wireless optical link (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Control Engineering and Communication Technology, ICCECT 2012, December 7, 2012 - December 9, 2012, Shenyang, Liaoning, China
作者:  
Guo J.;  Guo J.;  Wang H.;  Wang H.;  Wang H.
收藏  |  浏览/下载:31/0  |  提交时间:2013/03/25
An FPGA based transceiving synchronization method is demonstrated for Free Space Optical (FSO) communication system  which is discussed separately as the transmitting protocol and the receiving protocol. During the discussion of these two parts  the co-operation of them is also discussed. The transmitting protocol interfaces the outer input data with a parallel port  buffers the input data  encodes the input data stream  serializes the parallel data and outputs the serialized data. It also has an output management unit to manage the activity of each part of the transmitting protocol. The receiving protocol filters and synchronizes the input serial data stream  parallels the serial data stream  decodes the input data  checks received error  handles transmission exception and interfaces the outer receiver with a parallel port. The entire transceiving protocol could be programmed into a single FPGA chip to improve system integrity and reduce the system cost. The presented protocol could be taken as "protocol transparent" for outer interfaces  meaning that when interfacing the presented system to an outer system  users don't have to consider what protocol the outer system transceiving data stream is under  for example  the TCP/IP protocol or anything else  in the case that its I/O interface is a parallel port. Simulation and final experiment prove that the protocol presented is a working solution at a certain bit rate scale. 2012 IEEE.  
Physical layer design for free space optical communication (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Control Engineering and Communication Technology, ICCECT 2012, December 7, 2012 - December 9, 2012, Shenyang, Liaoning, China
作者:  
Wang H.;  Zhang Q.;  Guo J.;  Guo J.;  Wang H.
收藏  |  浏览/下载:30/0  |  提交时间:2013/03/25
A small size Free Space Optical Communication System is introduced  including the hardware and the hardware specified physical layer protocol. In detail  the rapid synchronization method to reduce the handshake bandwidth requirement is demonstrated. The hardware of the system includes the laser driver system  the signal amplifying and shaping system  the data interface system. The hardware specified physical layer protocol is used to interface the outer data  serialize and deserialize the data stream  check transmission errors and schedule the data transmission. The overall system is a FIFO-like system and the user can use it as if he's operating a FIFO. The system is designed mainly for terrestrial FSO link whose signal channel is the atmosphere. Due to the complex composition and activity of the atmosphere  this signal channel brings in great influence on the transmitting laser in it  for example  the absorption and scattering of the atmosphere molecules and aerosols  the scintillation of received laser power caused by the turbulence of the atmosphere  all of which results in a much higher Bit Error Rate (BER) of the communication system than wired communication systems leading to frequent resynchronization. In our system  the sampling clock is generated locally using multi-phase sampling technique rather than PLLbased clock recovery  which helps to rapid synchronization. 2012 IEEE.  
Earth elevation map production and high resolution sensing camera imaging analysis (EI CONFERENCE) 会议论文  OAI收割
Optoelectronic Imaging and Multimedia Technology, October 18, 2010 - October 20, 2010, Beijing, China
作者:  
Dai L.
收藏  |  浏览/下载:138/0  |  提交时间:2013/03/25
The Earth's digital elevation which impacts space camera imaging has prepared and imaging has analysed. Based on matching error that TDI CCD integral series request of the speed of image motion  statistical experimental methods-Monte Carlo method is used to calculate the distribution histogram of Earth's elevation in image motion compensated model which includes satellite attitude changes  orbital angular rate changes  latitude  longitude and the orbital inclination changes. And then  elevation information of the earth's surface from SRTM is read. Earth elevation map which produced for aerospace electronic cameras is compressed and spliced. It can get elevation data from flash according to the shooting point of latitude and longitude. If elevation data between two data  the ways of searching data uses linear interpolation. Linear interpolation can better meet the rugged mountains and hills changing requests. At last  the deviant framework and camera controller are used to test the character of deviant angle errors  TDI CCD camera simulation system with the material point corresponding to imaging point model is used to analyze the imaging's MTF and mutual correlation similarity measure  simulation system use adding cumulation which TDI CCD imaging exceeded the corresponding pixel horizontal and vertical offset to simulate camera imaging when stability of satellite attitude changes. This process is practicality. It can effectively control the camera memory space  and meet a very good precision TDI CCD camera in the request matches the speed of image motion and imaging. 2010 SPIE.  
Fabrication and testing 600mm diameter brazing SiC mirror (EI CONFERENCE) 会议论文  OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, November 19, 2008 - November 21, 2008, Chengdu, China
作者:  
Wang X.;  Zhang X.-J.;  Zhang Z.-Y.;  Zhang Z.-Y.;  Wang X.
收藏  |  浏览/下载:22/0  |  提交时间:2013/03/25
SiC is a preferential material for space large aperture mirror at present. Aperture of 1 meter sic mirror can meet most requirements of space optical systems. For larger aperture sic mirror  it is not economical and safe to make the monolithic body directly. The SiC mirror brazed assembly with several segments can solve these problems. In this paper  one 600 mm sic plane mirror as demonstration welded with 3 radial segments is roughly grinded to the required figure at first  then the mirror is finely grinded and polished by CCOS technology  the RMS of the figure error is less than 1/20 ( = 632.8nm) finally. The problems of the preferential removal near braze joint and material removing rate influenced by deformation of mirror surface are solved. Methods of reducing the residual stress of mirror are discussed. At last  some measurements and experiments are carried on  and the results conclude that the brazed SiC mirror can meet the requirement of large aperture optical systems. 2009 SPIE.  
Transceiving protocol designc for a free space optical communication system (EI CONFERENCE) 会议论文  OAI收割
2008 International Conference on Optical Instruments and Technology: Optical Systems and Optoelectronic Instruments, November 16, 2008 - November 19, 2008, Beijing, China
Hualong W.; Wanxin S.; Zhongbao X.
收藏  |  浏览/下载:58/0  |  提交时间:2013/03/25
A new transceiving protocol is demonstrated for a Free Space Optical (FSO) communication system  and it's discussed in two parts: the transmitting protocol and the receiving protocol. During the discussion of these two parts  the cooperation of them is also discussed. Different from wired communication  an FSO system modulates the data on a narrow beam of laser transmitting through the free space or the atmosphere  and the protocol presented in this paper is mainly optimized for terrestrial Free Space Optical links  in which the signal channel of the system is mainly the atmosphere. Due to the complex composition and activity of the atmosphere  this signal channel brings in great influence on the transmitting laser in it  for example  the absorption and scattering of the atmosphere molecules and aerosols  the scintillation of received laser power caused by the turbulence of the atmosphere  all of which results in a much higher Bit Error Rate (BER) of the communication system. Thus in designing a protocol for an FSO system  more effort should be taken in the encoding of the data stream  the synchronization of the data stream  error checking and exception handling. The main function of the transmitting protocol includes interfacing the outer input data with a parallel port  buffering the input data  encoding the input data stream  serializing the parallel data and output the serialized data. It also has an output management unit to manage the activity of each part of the transmitting protocol. The main function of the receiving protocol includes filtering and synchronizing the input serial data stream  paralleling the serial data stream  decoding the input data  error checking  exception handling and interfacing the outer receiver with a parallel port. The entire transceiving protocol could be programmed into a single FPGA chip to improve system integrity and reduce the system cost. The presented protocol could be taken as "protocol transparent" for outer interfaces  meaning that when interfacing the presented system to an outer system  you don't have to consider what protocol the outer system transceiving data stream is under  for example  the TCP/IP protocol or anything else  in the case that its I/O interface is a parallel port. Simulation and final experiment prove that the protocol presented is working fine at a certain bit rate scale. 2009 SPIE.  
Performance analysis of bit error rate for free space optical communication with tip-tilt compensation based on gamma-gamma distribution 期刊论文  OAI收割
Optica Applicata, 2009, 卷号: 39, 期号: 3, 页码: 533-545
作者:  
Wu HL(吴晗玲);  Yan HX(严海星);  Li XY;  Wu HL
收藏  |  浏览/下载:987/181  |  提交时间:2009/08/03