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	Temperature dependence of the receiver noise temperature and IF bandwidth of superconducting hot electron bolometer mixers 期刊论文 OAI收割 SUPERCONDUCTOR SCIENCE & TECHNOLOGY, 2014, 卷号: 27, 期号: 8, 页码: 0 作者: Zhang, W.; Miao, W.; Zhong, J. Q.; Shi, S. C.; Hayton, D. J. 收藏 \| 浏览/下载：24/0 \| 提交时间：2014/11/20 hot electron bolometer receiver noise temperature IF bandwidth phonon cooling
	The calibration of faint simulation star magnitude based on single photon count technique (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Advances in Imaging Detectors and Applications, June 17, 2009 - June 19, 2009, Beijing, China 作者: Xu S.-Y.; Guo J.; Guo J. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 A calibration method of faint star magnitude of the star scene simulation device is proposed in this paper. In the research of simulation star magnitude luminometers and CCD devices are the general calibration devices which are used to measure the illumination intensity and calibrate its magnitude. But if the simulation magnitude is only sixth magnitude its illumination intensity is only 1.010-8 Lux. This illumination intensity level is the lowest illumination intensity that the commercial luminometer can detect. Hence the simulation star magnitude lower than six magnitude cannot be calibrated by luminoters. Likewise CCD devices also need an additive cooler in this case. When the single photon characteristic is presented due to the low luminosity of simulating light sources the simulation star magnitude can be calibrated by detecting its photon flux of radiation with the method of single photon count. In this paper the detection principle of single photon based on a compact designed PMT detecting of the radiation level of simulation star magnitude is advanced. Especially a spectrum match method is proved theoretically to be an effective means for selecting PMT photosensitive type. In the case of the detection object of the simulation star in visible wavelength a analysis indicates that the material of tri-alkali cathode materials its best choice after being compared the Signal-to-Noise of photon detector of several PMT photosensitive materials based on the different spectrum match ratio of different object light sources and different cathode materials. An experiment is employed to show the relationship of control voltage of PMT and its dark counter the relationship of the environment temperature of PMT and its dark counter which proves its only decades of CPS at room temperature. The so low dark counter avoids a bulky cooler and is convenient for installing it on the star scene simulation equipment. Finally in the experiment of calibrating the simulation star magnitudes the ability of its calibration is confirmed to reaches up to 12m meanwhile its calibration error is within 0.2m. 2009 SPIE.
	Space camera imaging gain in-orbit adjusting strategy (EI CONFERENCE) 会议论文 OAI收割 2009 2nd International Conference on Intelligent Computing Technology and Automation, ICICTA 2009, October 10, 2009 - October 11, 2009, Changsha, Hunan, China 作者: Wang J.; He X. 收藏 \| 浏览/下载：17/0 \| 提交时间：2013/03/25 A Multi-Step Gain Adjusting Strategy (MSGAS) of space camera was proposed which was used to get higher SNR (Signal-Noise Rate) image. When the space camera working in poor light condition the CCD signal was so weak that it's difficult to get a clear image to reduce the quantization noise and improve the SNR we must amplify the CCD signal first and then quantize. The MSGAS was achieved by adjusting the gain of the CCD (Charge Couple Device) signal processor step by step the upper limit and lower limit were set if the MDN (Mean Digital Number) of a fixed length image data was not between the lower and upper limit the gain was adjusted step by step. In the experiment the upper limit lower limit and the step were set and the result of the experiment showed that MSGAS was robust and SNR was improved from 28 to 39. 2009 IEEE.
	Noise characteristic of laser diode pumped orange-yellow solid-state laser by intracavity sum-frequency of KTP Phase matching II (EI CONFERENCE) 会议论文 OAI收割 ICO20: Lasers and Laser Technologies, August 21, 2005 - August 26, 2005, Changchun, China Tan H.; Gao L. 收藏 \| 浏览/下载：17/0 \| 提交时间：2013/03/25 The laser diode pumped Nd: YVO4 orange-yellow laser has been presented in this paper. The fundamental wavelengths of 1064nm and 1342nm oscillate simultaneous to generate the 593.5nm wavelength by intracavity sumfrequency of KTP nonlinear crystal phase matching II. The noise characteristic of laser output has been measured and analyzed in different pumping power. The relations between the amplitude noise of sum-frequency output and the longitudinal mode of fundamental frequency have been researched. The results show that the sum-frequency output is low noise if the one of fundamental wavelengths is single longitudinal mode. The experiments show that amplitude noise of intracavity sum-frequency laser is lower than that of intracavity doubled frequency laser with the same structure.
	AE signal processing and DSP implementation based on wavelet packet analysis (EI CONFERENCE) 会议论文 OAI收割 ICMIT 2005: Information Systems and Signal Processing, September 20, 2005 - September 23, 2005, Changchun, China 作者: Zhao J.; Wang K. 收藏 \| 浏览/下载：13/0 \| 提交时间：2013/03/25 To improve the accuracy of AE (Acoustic Emission) testing the wavelet packet analysis was introduced to process the AE signals. Extraction of the fault characteristic information would be influenced greatly if the faulted AE signal was not effectively denoised. Based on discussing the fast searching algorithm of BWPB (Best Wavelet Packet Basis) adopting Shannon entropy a new method based on BWPB was presented to denoise the AE signal from the faulted composite plate. Analyzing was performed on the denoised signal and the fault characteristic information was exacted. To improve the real-time performance of the wavelet packet analysis algorithm it was performed on the DSP (Digital Signal Processing) chip TMS320VC5409. The experimental results show that the algorithm can not only reduce the noise by 10dB but also effectively extract the faulted characteristics information from the AE signal.
	An anomalous peak on intermediate frequency response of superconductor-isolator-superconductor mixers and its effect on mixing performance 期刊论文 OAI收割 JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS, 2004, 卷号: 43, 期号: 5A, 页码: L617-L619 作者: Shan, WL; Wang, MJ; Shi, SC; Irimajiri, Y; Noguchi, T 收藏 \| 浏览/下载：14/0 \| 提交时间：2012/12/22 IF response IF peak SIS mixer Josephson weak link mixing performance noise temperature
	Characterization of the IF noise of a submillimeter SIS receiver 期刊论文 OAI收割 INTERNATIONAL JOURNAL OF INFRARED AND MILLIMETER WAVES, 2004, 卷号: 25, 期号: 2, 页码: 383-391 作者: Shan, WL; Irimajiri, Y; Shi, SC; Manabe, T 收藏 \| 浏览/下载：15/0 \| 提交时间：2012/12/22 submillimeter SIS receiver IF noise output mismatching