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The Ground Simulation of Spacecraft Discharge Impacts on the Space Environment Detectors 期刊论文  OAI收割
IEEE TRANSACTIONS ON PLASMA SCIENCE, 2016, 卷号: 44, 期号: 7, 页码: 1247-1253
作者:  
Wang, Jinlong;  Zhang, Zhenlong
收藏  |  浏览/下载:23/0  |  提交时间:2016/11/08
Space- and ground-based CO2 measurements: A review SCI/SSCI论文  OAI收割
2016
作者:  
Yue T. X.;  Zhang, L. L.;  Zhao, M. W.;  Wang, Y. F.;  Wilson, J.
收藏  |  浏览/下载:54/0  |  提交时间:2016/12/16
Orbit improvement for Chang'E-5T lunar returning probe with GNSS technique 期刊论文  OAI收割
ADVANCES IN SPACE RESEARCH, 2015, 卷号: 56, 期号: 11, 页码: 2473-2482
作者:  
Fan, Min;  Hu, XiaoGong;  Dong, Guangliang;  Huang, Yong;  Cao, Jianfeng
收藏  |  浏览/下载:70/0  |  提交时间:2016/01/14
Research on energy characteristics of aerospace relay mirror system (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Electronic and Mechanical Engineering and Information Technology, EMEIT 2011, August 12, 2011 - August 14, 2011, Harbin, China
Liu C.; Zhong X.; Piao Y.; Jin G.
收藏  |  浏览/下载:29/0  |  提交时间:2013/03/25
Aerospace Relay Mirror System (ARMS) as a new concept weapon used in reflection of High Energy Laser (HEL) in space is studied. It extends the attacking range of Ground Based Laser (GBL) weapons enormously. Relevant researches have been carried out for many years. The structures and operating theory of the entire system consists of ground-based high energy laser weapon and space-based relay mirror. The main work of this study is focused on the analysis of relay mirror energy characteristics to deduce the relationship among the attacking range of weapon and diameter of ARMS and target irradiance. Calculation examples are also given. The results proved the strong points and feasibility of ARMS theoretically further. It is summarized that more importance should be attached to ARMS development. The results given in this paper can be reference of an actual ARMS system to some extends. 2011 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:47/0  |  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.  
Adaptive Wiener filtering with Gaussian fitted point spread function in image restoration (EI CONFERENCE) 会议论文  OAI收割
2011 IEEE 2nd International Conference on Software Engineering and Service Science, ICSESS 2011, July 15, 2011 - July 17, 2011, Beijing, China
作者:  
Yang L.;  Zhang X.;  Zhang X.;  Zhang X.;  Yang L.
收藏  |  浏览/下载:44/0  |  提交时间:2013/03/25
In the imaging process of the space remote sensing camera  there was degradation phenomenon in the acquired images. In order to reduce the image blur caused by the degradation  the remote sensing images were restored to give prominence to the characteristic objects in the images. First  the frequency-domain notch filter was adopted to remove strip noises in the images. Then using the ground characters with the knife-edge shape in the images  the point spread function of the imaging system was estimated. In order to improve the accuracy  the estimated point spread function was corrected with Gaussian fitting method. Finally  the images were restored using the adaptive Wiener filtering with the fitted point spread function. Experimental results of the real remote sensing images showed that almost all strip noises in the images were eliminated. After the denoised images were restored  its variance and its gray mean gradient increased  also its laplacian gradient increased. Restoration with Gaussian fitted point spread function is beneficial to interpreting and analyzing the remote sensing images. After restoration  the blur phenomenon of the images is reduced. The characters are highlighted  and the visual effect of the images is clearer. 2011 IEEE.  
Improved STAP algorithm based on APES 期刊论文  OAI收割
JOURNAL OF SYSTEMS ENGINEERING AND ELECTRONICS, 2011, 卷号: 22, 期号: 3, 页码: 387-392
作者:  
Zhang, Yan;  Zhang, Yunhua;  Gu, Xiang
收藏  |  浏览/下载:16/0  |  提交时间:2014/12/15
High precision test method for dynamic imaging of space camera (EI CONFERENCE) 会议论文  OAI收割
2010 IEEE International Conference on Advanced Computer Control, ICACC 2010, March 27, 2010 - March 29, 2010, 445 Hoes Lane - P.O.Box 1331, Piscataway, NJ 08855-1331, United States
作者:  
Jin L.-X.;  Zhang K.;  Zhang K.;  Zhang K.;  Zhang K.
收藏  |  浏览/下载:26/0  |  提交时间:2013/03/25
A test method for dynamic imaging of space TDICCD (Time Delay and Integration Charge Coupled Devices) camera was presented in this paper. The test method adopted the PLL (Phase Locked Loop) technology and CMAC (Cerebella Model Articulation Controller) friction compensation as control strategy. Furthermore  According to this method  a test system for dynamic imaging of space TDICCD camera was designed and implemented. The system simulated the movement of the ground objects relative to the space aerocraft  to validate the capability of image speed match and the dynamic imaging quality of TDICCD camera. The design adopted a precision turntable and a drift turntable to simulate the movement around the earth and the drift motion in different latitude due to the rotation of earth  of the aerocraft. The turntables were drived by permanent magnet torque motor which was powered by PWM (Pulse Width Modulation). The system adopted DSP (Digital Signal Processor) as the control core and reached a very high performance. The experimental results showed that the steady speed error was better than 0.01 % and the instantaneous speed error reached 0.0267%. The precision of the test system designed met the requirement for dynamic imaging of TDICCD camera. 2010 IEEE.  
Inspection focus technology of space tridimensional mapping camera based on astigmatic method (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optoelectronic Materials and Devices for Detector, Imager, Display, and Energy Conversion Technology, April 26, 2010 - April 29, 2010, Dalian, China
作者:  
Wang Z.;  Wang Z.;  Zhang L.;  Zhang L.
收藏  |  浏览/下载:26/0  |  提交时间:2013/03/25
The CCD plane of the space tridimensional mapping camera will be deviated from the focal plane(including the CCD plane deviated due to camera focal length changed)  under the condition of space environment and vibration  impact when satellite is launching  image resolution ratio will be descended because defocusing. For tridimensional mapping camera  principal point position and focal length variation of the camera affect positioning accuracy of ground target  conventional solution is under the condition of vacuum and focusing range  calibrate the position of CCD plane with code of photoelectric encoder  when the camera defocusing in orbit  the magnitude and direction of defocusing amount are obtained by photoelectric encoder  then the focusing mechanism driven by step motor to compensate defocusing amount of the CCD plane. For tridimensional mapping camera  under the condition of space environment and vibration  impact when satellite is launching  if the camera focal length changes  above focusing method has been meaningless. Thus  the measuring and focusing method was put forward based on astigmation  a quadrant detector was adopted to measure the astigmation caused by the deviation of the CCD plane  refer to calibrated relation between the CCD plane poison and the asrigmation  the deviation vector of the CCD plane can be obtained. This method includes all factors caused deviation of the CCD plane  experimental results show that the focusing resolution of mapping camera focusing mechanism based on astigmatic method can reach 0.25 m. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Manufacture of 1.2m reaction bonded silicon carbide mirror blank CFID (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, April 26, 2010 - April 29, 2010, Dalian, China
作者:  
Zhang G.;  Zhang G.;  Zhang G.
收藏  |  浏览/下载:30/0  |  提交时间:2013/03/25
Silicon carbide (SiC) is a new type candidate material for large-scale lightweight space mirror. Its low thermal distortion  high stiffness  fine optical quality and dimensional stability  make SiC an ideal material for large space born telescope. Since ten years Changchun institute optics  fine mechanics and physics (CIOMP) has developed reaction bonded SiC (RB-SiC) technology for space application  and can fabricate RB-SiC mirror with scale less than 1.0 meter for telescope. The green body is prepared with gel-casting method which is an attractive new ceramic forming process for making high-quality  complex-shaped ceramic parts. And then unmolding  drying  binder burning out  reacting bonded  the RB-SiC can be obtained. But with the development of space-born or ground telescope  the scale of primary mirror has exceeded 1.0 meter. So CIOMP has developed an assembly technique which called novel reaction-formed joint technology for larger RB-SiC mirror blank. The steps include joining of green bodies with mixture comprised of SiC particles and phenolic resin etc  firing  machining and sintering. Joining the 1.2 meter RB-SiC mirror blank by the novel reaction-formed joint technology. And testing the welding layer's performance  the results show that the thickness of 54-77m  the microstructure and thermal property can be comparable to the substrate and the mechanical property are excellent in bending strength of 307MPa. 2010 Copyright SPIE - The International Society for Optical Engineering.