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	Laser pulse coded signal frequency measuring device based on DSP and CPLD (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Laser Sensing and Imaging; and Biological and Medical Applications of Photonics Sensing and Imaging, May 24, 2011 - May 26, 2011, Beijing, China 作者: Zhang H.-B.; Wang T.-F.; Guo R.-H.; Li Y.; Li Y. 收藏 \| 浏览/下载：57/0 \| 提交时间：2013/03/25 Laser pulse code is an anti-jamming measures used in semi-active laser guided weapons. On account of the laser-guided signals adopting pulse coding mode and the weak signal processing it need complex calculations in the frequency measurement process according to the laser pulse code signal time correlation to meet the request in optoelectronic countermeasures in semi-active laser guided weapons. To ensure accurately completing frequency measurement in a short time it needed to carry out self-related process with the pulse arrival time series composed of pulse arrival time calculate the signal repetition period and then identify the letter type to achieve signal decoding from determining the time value number and rank number in a signal cycle by Using CPLD and DSP for signal processing chip designing a laser-guided signal frequency measurement in the pulse frequency measurement device improving the signal processing capability through the appropriate software algorithms. In this article we introduced the principle of frequency measurement of the device described the hardware components of the device the system works and software analyzed the impact of some system factors on the accuracy of the measurement. The experimental results indicated that this system improve the accuracy of the measurement under the premise of volume real-time anti-interference low power of the laser pulse frequency measuring device. The practicality of the design reliability has been demonstrated from the experimental point of view.
	An improved fast parallel SPIHT algorithm and its FPGA implementation (EI CONFERENCE) 会议论文 OAI收割 2010 2nd International Conference on Future Computer and Communication, ICFCC 2010, May 21, 2010 - May 24, 2010, Wuhan, China 作者: Jin L.-X.; Tao H.-J.; Wu Y.-H. 收藏 \| 浏览/下载：31/0 \| 提交时间：2013/03/25 In view of the current stringent need to the real-time compression algorithm of the high-speed and high-resolution image such as remote sensing or medical image and so on in this paper No List SPIHT (NLS) algorithm has been improved and a fast parallel SPIHT algorithm is proposed which is suitable to implement with FPGA. It can deal with all bit-planes simultaneously and process in the speed of 4pixels/period so the encoding time is only relative to the image resolution. The experimental results show that the processing capacity can achieve 200MPixels/s when the input clock is 50MHz the system of this paper need 2.29ms to complete lossless compression of a 512x512x8bit image and only requires 1.31ms in the optimal state. The improved algorithm keeps the high SNR unchanged increases the speed greatly and reduces the size of the needed storage space. It can implement lossless or lossy compression and the compression ratio can be controlled. It could be widely used in the field of the high-speed and high-resolution image compression. 2010 IEEE.
	In situ long trace profiler for measurement of Wolter type-I mirror (EI CONFERENCE) 会议论文 OAI收割 Advances in Metrology for X-Ray and EUV Optics III, August 1, 2010 - August 2, 2010, San Diego, CA, United states 作者: Chen B.; Chen B. 收藏 \| 浏览/下载：39/0 \| 提交时间：2013/03/25 The surface profile of Wolter type-I mirror has a great impact on the performance of Solar X-ray Telescope. According to the existing fabrication instrument and experimental conditions in our lab an in situ Long Trace Profiler is developed and set up on the fabrication instrument in order to measure the surface profile of Wolter mirror in real time during fabrication process. Its working mechanism structural parameters and data processing algorithm are investigated. The prototype calibrated by a standard plane mirror is used to measure a sample of Wolter type-I mirror. The results show that our prototype can achieve an accuracy of 2.6rad rms for slope error with a stability of 1.33rad during the whole measurement period. This can meet further fabrication requirements. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Small roll angle measurement based on auto-collimation and moire fringe (EI CONFERENCE) 会议论文 OAI收割 2009 International Conference on Optical Instruments and Technology - Optoelectronic Measurement Technology and Systems, October 19, 2009 - October 22, 2009, Shanghai, China Bai X.-G.; Cai S.; Qiao Y.-F.; Dai M. 收藏 \| 浏览/下载：40/0 \| 提交时间：2013/03/25 A novel method for small roll angle measurement based on auto-collimation and moire fringe is presented. A right-angle prism is used as an indicator of small roll angle around the optical axis and a CCD is used to collect moire fringes that are generated by scale grating image which is reflected by prism and index grating. Any small roll angle of the prism will change the include angle of the grating pair and meanwhile induce a change in the moire fringe period. The relationship between roll angle and period of moire fringes is established. The period data is obtained by image processing. The experimental result certifies that the principle of small angle measurement method based on auto-collimation and moire fringe is correct and feasible. The measuring error is smaller than 0.2 within 7 range compared with 0.2 autocollimator. 2009 SPIE.
	Design and DSP implementation of star image acquisition and Star point fast acquiring tracking (EI CONFERENCE) 会议论文 OAI收割 2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 2, 2005 - November 5, 2005, Zian, China 作者: Wang X.; Wang X.; Wang X. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 Star sensor is a special high accuracy photoelectric sensor. Attitude acquisition time is an important function index of star sensor. In this paper the design target is to acquire 10 samples per second dynamic performance. On the basis of analyzing CCD signals timing and star image processing a new design and a special parallel architecture for improving star image processing are presented in this paper. In the design the operation moving the data in expanded windows including the star to the on-chip memory of DSP is arranged in the invalid period of CCD frame signal. During the CCD saving the star image to memory DSP processes the data in the on-chip memory. This parallelism greatly improves the efficiency of processing. The scheme proposed here results in enormous savings of memory normally required. In the scheme DSP HOLD mode and CPLD technology are used to make a shared memory between CCD and DSP. The efficiency of processing is discussed in numerical tests. Only in 3.5ms is acquired the five lightest stars in the star acquisition stage. In 43us the data in five expanded windows including stars are moved into the internal memory of DSP and in 1.6ms five star coordinates are achieved in the star tracking stage.
	Period of processing on serial production line, optimal scheduling and application 期刊论文 OAI收割 DISCRETE EVENT DYNAMIC SYSTEMS-THEORY AND APPLICATIONS, 1999, 卷号: 9, 期号: 1, 页码: 9-21 作者: Chen, WD; Xu, J; Liang, QH \| 收藏 \| 浏览/下载：37/0 \| 提交时间：2018/07/30 DEDS max-algebra non-blocking optimal control period of processing optimal scheduling