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	The design of high speed image acquisition system over Gigabit Ethernet (EI CONFERENCE) 会议论文 OAI收割 2010 IEEE International Conference on Wireless Communications, Networking and Information Security, WCNIS 2010, June 25, 2010 - June 27, 2010, Beijing, China 作者: Zhang W.; He X.; Zhang W. 收藏 \| 浏览/下载：36/0 \| 提交时间：2013/03/25 The applications based on traditional digital cameras have been limited by distance cost and networking. Gigabit Ethernet is a data transmission standard based on the IEEE 802.3 protocol brings several benefits to image transmission. In this paper we compare the main features of Gigabit Ethernet and traditional digital camera interfaces. And we design a high speed image acquisition system which overcomes these application limitations by allowing cameras to send imaging data over Gigabit Ethernet. In this system we design a highly efficient bidirectional conversion device based on FPGA converts imaging data from a camera to IP packets based on UDP protocol and sends it to PCs over inexpensive Cat-5 copper LAN cable. At the PC the Cat-5 cable plugs into a standard Gigabit Ethernet NIC(network interface card) eliminating the need for a frame grabber. An communications application software is used to acquire the network data construct and display the image. A simple and efficient acknowledge and resend mechanism was used to guarantee packet delivery. The system architecture and the communication protocol are discussed in details the experiment and results are presented in this paper. 2010 IEEE.
	A digital image processing system based on DSP (EI CONFERENCE) 会议论文 OAI收割 2nd International Conference on Information Engineering and Computer Science, ICIECS 2010, December 25, 2010 - December 26, 2010, Wuhan, China 作者: Liu Y.; He X.; Liu Y.; Liu Y. 收藏 \| 浏览/下载：9/0 \| 提交时间：2013/03/25 In order to detect the target position real-timely a real time target detecting system based on tms320F2812 DSP and Spartan3-SC3S400 FPGA is designed. The design hardware structure a target detecting method and software char flow of FPGA and DSP are presented. The system is tested by a 1Kx1K image the processing time is 1.3ms experiments results show that the method is feasible the simple design and stable correct results make this method very ascendant in practical application. 2010 IEEE.
	Implementation and stability analysis of the fuzzy controller based on electric-driven simulation turntable (EI CONFERENCE) 会议论文 OAI收割 ISECS International Colloquium on Computing, Communication, Control, and Management, CCCM 2008, August 3, 2008 - August 4, 2008, Guangzhou, China Xie M.-J.; Wang L.-M.; Wang Z.-Q. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 Fuzzy controller was used to resolve the problem of fast tracking and overshoot in electric-driven simulation turntable for its essence belongs to PD control In this system the control rules of fuzzy controller were established according to the step dynamic response process for the speed loop of this system was predigested to be second-orders system. The describing function method was adopted to analyze the stability of the fuzzy control system. It gave the information of stability of system intuitively. The fuzzy controller had been applied in this system successfully. The simulation turntable had no overshooting nearly when its step input signal was close to 90. Experimental results show the implementation method of fuzzy controller is not only simple but also effectual in engineering practice. It also provides an approach of design of fuzzy controller for motion control system. 2008 IEEE.
	Design of high-resolution fourier transform lens (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Advanced Optical Manufacturing Technologies, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Zhang L.; Zhang L. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 With the development of optical information processing high-resolution Fourier transform lens has often been used in holographic data storage system spatial filtering and observation of particles. This paper studies the optical design method of high-resolution Fourier transform optical lenses system which could be used in particles observation and holographic data storage system. According to Fourier transform relation between object and its frequency plane and the theory of geometrical optics the system with working wavelength 532nm and resolution 3 m was designed based on ZEMAX. A multi-configuration method was adopted to optimize the system's lenses. In the optical system a diaphragm was placed at the system's spectrum plane and the system demanded a low vacuum to cut down the influences of atmosphere and other particles. The result of finite element analysis indicated that the influences of vacuum pumping to optics spacing and mirror surface shape very minor and the imaging quality not being affected. This system has many advantages such as simple structure good image quality and a high resolution of 3 m. So it has a wide application prospect and can be used both in holographic data storage system and particles observation.
	Design of dual-FOV refractive/diffractive LWIR optical system (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Advanced Optical Manufacturing Technologies, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Wang L.-J.; Zhang J.-P.; Wang L.-J.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 An infrared-optical zoom system using binary element is proposed in this paper. The two main advantages of the zoom system introducing here are: bigger F-number and lower cost. The primary optical properties are: F/#=1 Second Others zoom ratio =1:4 binary element is used to correct the chromatical aberration by taking the advantage of negative dispersion characteristics and the cost of the system is lower than that of conventional ones with Zinc Selenide (Znse) material at the same level. In the binary element is rotational symmetric with one step which is easy to fabricate in order to balance 5th spherical aberration and dual field are 26.6 and 5.6respectively. Wider field of view is used for search and the smaller one is used for imaging details. This system uses un-cooled infrared detector with 320240 pixels and 45m pixel size. The F-number matches the sensitivity range of the detector array. Three aspects are considered during design process to make the system more satisfactory and more achievable. First 5th coma aberration and 5th astigmatic aberration the manner of zoom is accomplished by exchanging tow lenses into the smaller field of view system layout. The lens exchange manner faces the requirement of simple system structure and good image quality in both focal points. It can also make the system more feasible in the alignment process than mechanical-zooming manner and optical-zooming manner high-order asphere surfaces with 2th order to 10 th order are also hired in the system. Asphere surface is useful in compressing the system and improving optical system transmittance. This kind asphere surface is on industrial level featuring low cost and easy to fabricate. It is shown that good image quality can achieved by implementing five Germanium lenses and the transmittance of system is 72%. All aberrations are diffraction-limited both spherical aberration and astigmatic aberration are corrected. When the field of view(FOV) is 26.6 and the focal length is 152mm MTF at Nyquist frequency(11lp/mm) is great than 0.7. The spherical aberration is -0.0073. The coma aberration is 0.0978 and the astigmatic aberration is -0.013. When the field of view(FOV) is 5.6 and the focal length is 38mm MTF at Nyquist frequency is great than 0.8 with spherical aberration -0.0046 the coma aberration 0.055 and astigmatic aberration 0.034.
	CMOS APS imaging system application in star tracker (EI CONFERENCE) 会议论文 OAI收割 Advanced Materials and Devices for Sensing and Imaging II, November 8, 2004 - November 10, 2004, Beijing, China 作者: Li J.; Liu Y.; Liu Y.; Liu Y.; Liu J. 收藏 \| 浏览/下载：58/0 \| 提交时间：2013/03/25 Small satellites are capable of performing space explore missions that require accurate attitude determination and control. However low weight size power and cost requirements limit the types of attitude sensor of small craft such as CCD are not practical for small satellites. CMOS APS is a good substitute for attitude sensors of small craft. Some of the technical advantages of CMOS APS are no blooming single power low power consumption small size and little support circuitry direct digital output simple to system design in particular radiation-hard characteristic compare with CCD. This paper discusses the application probability of CMOS APS in star tracker for small satellites further more a prototype ground-based star camera based on STAR250 CMOS image sensor has been built. In order to extract stars positions coordinates subpixel accuracy centroiding algorithm has been developed and tested on some ground-based images. Moreover the camera system star sensitivity and noise model are analyzed and the system accuracy is been evaluated. Experimental results indicate that a star camera based on CMOS APS is a viable practical attitude sensor appropriate for space small satellites.