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eLoran系统新型数据调制/信道编码方案设计与评估 期刊论文  OAI收割
全球定位系统, 2020, 卷号: 45, 期号: 5, 页码: 84
作者:  李婉清;  王建辉;  李实锋;  傅其祥
  |  收藏  |  浏览/下载：22/0  |  提交时间：2021/11/29
A Fault Location Algorithm Based on Convolutional Neural Network for Sensor System of Seafloor Observatory Network 会议论文  OAI收割
Marseille, France, June 17-20, 2019
作者:  Sun K(孙凯)
  |  收藏  |  浏览/下载：34/0  |  提交时间：2019/12/23
Doppler-robust high-spectrum-efficiency VCM-OFDM scheme for low Earth orbit satellites broadband data transmission 期刊论文  OAI收割
IET COMMUNICATIONS, 2018, 卷号: 12, 期号: 1, 页码: 35-43
作者:  Li, Jionghui;  Xiong, Weiming;  Sun, Geng;  Wang, Zhugang;  Huang, Yonghui
  |  收藏  |  浏览/下载：77/0  |  提交时间：2018/03/02
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：36/0  |  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.  
Design of high speed and parallel compression system used in the big area CCD of high frame frequency (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Precision Engineering and Non-Traditional Machining, PENTM 2011, December 9, 2011 - December 11, 2011, Xi'an, China
作者:  Li G.-N.;  Jin L.-X.;  Zhang R.-F.;  Wang W.-H.;  Li G.-N.
收藏  |  浏览/下载：55/0  |  提交时间：2013/03/25
According to the area CCD camera of characteristics  such as high resolution capacity and high frame frequency  this paper puts forward a high speed and parallel image compression system of high integration degree. Firstly  according to the work principle of the area CCD  FPGA is adopted to realize the timing driving and multichannel and parallel analog signal handling to raise the export frame frequency of the area CCD. Secondly  with an image compression scheme based on FPGA embedded processor MicroBlaze and ADV212 compression chip  real time image compression and the high speed area CCD are realized. Finally  by detecting the analog signal of the area CCD output  the real time compression of the big area CCD image is carried out in different compression ratios and the compression performance is analyzed. Experiment result shows that this scheme can realize real time image compression with the biggest data rate of 520Mbps. When compression bit ratio is 0.15  the signal-to-noise ratio of peak value can reach 36 dB. Image collection and image compression are integrated  which reduces the data transmission between them and improves systematic integration degree.  
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：34/0  |  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.  
Design of motion compensation mechanism of satellite remote sensing camera (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Gu S.; Yan Y.; Xu K.; Jin G.
收藏  |  浏览/下载：49/0  |  提交时间：2013/03/25
With the development of aerospace remote sensing technology  the ground resolution of remote sensing camera enhances continuously. Since there is relative motion between camera and ground target when taking pictures  the target image recorded in recording media is moved and blurred. In order to enhance the imaging quality and resolution of the camera  the image motion had to be compensated. In order to abate the effect of image motion to image quality of space camera and improve the resolution of the camera  the compensation method of image motion to space camera is researched. First  the reason of producing drift angle and adjustment principle are analyzed in this paper. This paper introduce the composition and transmission principle of image motion compensation mechanism. Second  the system adopts 80C31 as controller of drift angle  and adopts stepping motor for actuators  and adopts absolute photoelectric encoder as the drift Angle measuring element. Then the control mathematical model of the image motion compensation mechanism are deduced  and it achieve the closed-loop control of the drift angle position. At the last  this paper analyses the transmission precision of the mechanism. Through the experiment  we measured the actual precision of the image motion compensation mechanism  and compared with the theoretical analysis. There are two major contributions in this paper. First  the traditional image motion compensation mechanism is big volume and quality heavy. This has not fit for the development trend of space camera miniaturization and lightweight. But if reduce the volume and quality of mechanism  it will bring adverse effects for the precision and stiffness of mechanism. For this problem  This paper designed a image motion compensation that have some advantages such as small size  light weight at the same time  high precision  stiffness and so on. This image motion compensation can be applicable to the small optics cameras with high resolution. Second  the traditional mechanism control need to corrected  fitting and iterative for the control formula of mechanism. Only in this way  we can get the optimal control mathematical model. This paper has high precision of the control formula derived. It can achieve the high precision control without fitting  It also simplify the difficulty of control mathematical model establishment. This paper designed the range of adjusting of image motion compensation mechanism between -5 +5. Based on choosing-5  -4  -3  -2  -1  0  +1  +2  +3  +4  +4 as the expectation value of the imaginary drift angle  we get ten groups of the fact data in adjusting drift angle measured. The test results show that the precision of the drift angle control system can be achieved in 1. It can meet the system requirements that the precision of the control system is less than 3'  and it can achieve the high-precision image motion compensation. 2011 SPIE.  
DVI interface, optical fiber video transceiver used in LED display system (EI CONFERENCE) 会议论文  OAI收割
2011 IEEE 3rd International Conference on Communication Software and Networks, ICCSN 2011, May 27, 2011 - May 29, 2011, Xi'an, China
作者:  Wang R.;  Li S.
收藏  |  浏览/下载：33/0  |  提交时间：2013/03/25
A professional DVI-Video optical fiber transceiver was designed based on FPGA (Field Programmable Gate Array) in order to meet the need of real-time LED display. The system could be used to transmit a non-loss  real-time video source whose resolution was 1024 768 and refresh rate was 60Hz in a single mode optical fiber. The top-down design method was used while programming FPGA. Some module design ideas were discussed including video data acquisition  caching  framing  frame detecting and video reproducing. The required bandwidth of each module was analyzed and calculated in details. Some relevant simulation results were also given. In practical test  real-time video display was achieved. And the transmission rate of coded data was up to 2Gbps  and the transmission distance could reach 10km. 2011 IEEE.  
Research of remote control for Chinese Antarctica telescope based on Iridium satellite communication 会议论文  OAI收割
San Diego, California, USA, 2010-6-27
作者:  shihai Yang;  Lingzhe Xu
收藏  |  浏览/下载：22/0  |  提交时间：2014/01/05
Optical transmission system based on 10GBASE-X (EI CONFERENCE) 会议论文  OAI收割
2010 3rd International Conference on Advanced Computer Theory and Engineering, ICACTE 2010, August 20, 2010 - August 22, 2010, Chengdu, China
作者:  Gao S.-J.
收藏  |  浏览/下载：36/0  |  提交时间：2013/03/25
In order to further enhance the bandwidth of the data communication system in theodolite  The whole design of the PMD is realized by using Xenpak optical module. Its duty is responsible for converting 4-channel parallel 3.125Gbps data stream into a serial 10.3126Gbps data stream  a single channel serial optical transmission system was designed based on the studying of the 10BASE-X Gigabit Ethernet physical layer technology which meets the IEEE standard. The conversion between the 64-bit 156.25MHz TTL signals and the 4 channel 3.125Gbps PCML differential signals is carried out by FPGA  and sending out it in the form of light signals. The experimental results show that data transmission capacity was achieved a 10Gbps in the single-channel optical transmission system. It can conduct short distance transmission. The system delay is about 31lns. The bit error rates no more than 10-12  which satisfies the system demand. 2010 IEEE.