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	Comparison of simulated backgrounds with in-orbit observations for HE, ME, and LE onboard Insight-HXMT 期刊论文 OAI收割 Astrophysics and Space Science, 2020, 卷号: 365, 页码: 158 作者: HXMT \| 收藏 \| 浏览/下载：52/0 \| 提交时间：2022/02/08 Insight-HXMT Geant4 simulation Background observation Astrophysics - Instrumentation and Methods for Astrophysics Abstract: Insight-HXMT, the first X-ray astronomical satellite in China, aims to reveal new sources in the Galaxy and to study fundamental physics of X-ray binaries from 1 to 250 keV. It has three collimated telescopes, the High Energy X-ray telescope (HE), the Medium Energy X-ray telescope (ME), and the Low Energy X-ray telescope (LE). Before the launch, in-orbit backgrounds of these three telescopes had been estimated through Geant4 simulation, in order to investigate the instrument performance and the achievement of scientific goals. In this work, these simulated backgrounds are compared with in-orbit observations. Good agreements are shown for all three telescopes. For HE, (1) the deviation of the simulated background rate after two years of operation in space is 5 % from the observation (2) the total background spectrum and the relative abundance of the 67 keV line show long-term increases both in simulations and observations. For ME, (1) the deviation of simulated background rate is within 15 % from the observation, and (2) there are no obvious long-term increase features in the background spectra of simulations and observations. For LE, the background level given by simulations is also consistent with observations. The consistencies of these comparisons validate that the Insight-HXMT mass model, i.e., space environment components and models adopted, physics processes selected, and detector constructions built, is reasonable. However, the line features at 7.5 and 8.0 keV, which are obvious in the observed spectra of LE, are not evident in simulations. This might result from uncertainties in the LE constructions.
	ACMR SYSTEM DESCRIPTION AND PERFORMANCE 会议论文 OAI收割 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), Quebec, CANADA, JUL 13-18, 2014 作者: Zhang, Dehai; Wang, Zhenzhan; Wang, Hongjian; Zhao, Jin; Li, Yun 收藏 \| 浏览/下载：26/0 \| 提交时间：2015/09/18 ACMR Calibration In-orbit performance
	AUTONOMOUS INTEGRATED NAVIGATION USING X-RAY PULSARS AND ASTEROIDS 会议论文 OAI收割 63rd International Astronautical Congress 2012, IAC 2012, Naples, Italy, 2012 Yang Chengwei; Gao Dong; Zheng Jianhua 收藏 \| 浏览/下载：39/0 \| 提交时间：2014/04/30 To improve the navigation performance of the spacecraft during interplanetary cruise a novel integrated navigation system is proposed. For X-ray pulsar navigation (XNAV) is a hot and prospective research subject and the optical navigation using asteroids is practical in space engineering we designed an autonomous navigation system using one X-ray detector and one navigation camera. The measurement models of the XNAV based on the time difference of arrival and the optical navigation based on the images of asteroids are presented. To enhance practicality the X-ray pulsars and asteroids are observed by turns. The batch least square filter used by Deep Space I is adopted to estimate the system state. The numerical simulation results show that the integrated navigation is feasible on the interplanetary cruise orbit. Moreover compared with the XNAV and the optical navigation the integrated navigation system can provide higher navigation performance.
	A hybrid median filter for enhancing dim small point targets and its fast implementation (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Multimedia and Signal Processing, CMSP 2011, May 14, 2011 - May 15, 2011, Guilin, Guangxi, China Yang Q. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 Weak stars and middle altitude orbit satellites or high altitude orbit satellites are presented as dim point targets in images of astronomical observation. They have low intensity and occupy few pixels in image. In most situations the background of sky is always ununiform and there exists pulse noises. Thus results in targets submerging in background noises and low signal noise ratio (SNR). Median filter is an effective method for removing pulse noise. But it can blur image after modifying gray of non-noise pixels when image has low SNR. A hybrid median filter algorithm is proposed to process low SNR dim point targets image. The newly proposed method can suppress the pulse noises also can increase target $SNR$ and does not add extra fake targets. The time complexity of median filter is O(N2)(N is the widow size) and is difficult to implement in hardware. For quasi real time application a fast implementation of our hybrid median filter is proposed to reduce the time complexity to O(N). Experimental results show that the newly proposed algorithm is superior to ordinary median filter and fast median filter by comparing visual effect and performance. 2011 IEEE.
	Electronic system design of ultraviolet ozone vertical profile probe for aerography satellite (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 Song K.; Wang S. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 The design of ultraviolet ozone vertical profile probe is illustrated and the electronic system is introduced in detail. The device is a compact high precision ultraviolet-vacuum ultraviolet spectral radiometer and is used to measure atmospheric solar backscattering spectral radiance and solar spectral irradiance. Noise of the system is analyzed and Numeric accumulation and synchronous demodulation was used to decrease the noise and the zero-drift of the instrument. The solar irradiance at altitude 830 km in 160-400 nm and the backscattering solar spectral radiance in the ultraviolet ozone absorption band at 12 wavelengths from 250 nm to 340 nm are obtained. Test results on orbit show that all the requested function is met successfully and the performance is stable. 2011 IEEE.
	Memoryless polynomial RLS adaptive filter for trajectory target tracking (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Computer Modeling and Simulation, ICCMS 2010, January 22, 2010 - January 24, 2010, Sanya, China 作者: Liu J.; Liu J.; Liu J. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 In order to find an effective solution to trajectory target tracking a memoryless polynomial adaptive filter is proposed in this paper. Unlike Volterra adaptive filter the proposed memoryless polynomial filter is composed of different monomials which can fit orbit trajectory very well. Besides the memoryless polynomial filter can be separated into a linearization filter and a transversal filter. Analogous to linear RLS adaptive filter a RLS adaptive filter is derived from the memoryless polynomial filter called Memoryless polynomial RLS adaptive filter (MLPRLS adaptive filter). Experiments show that the proposed filters have better performance than that of normal RLS filters in trajectory tracking. 2010 IEEE.
	Memoryless polynomial LMS adaptive filter for orbit object tracking (EI CONFERENCE) 会议论文 OAI收割 2009 International Conference on Information Engineering and Computer Science, ICIECS 2009, December 19, 2009 - December 20, 2009, Wuhan, China 作者: Wang P. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 In order to find a fast and effective solution to orbit object tracking a memoryless polynomial adaptive filter is proposed in this paper. Unlike Volterra adaptive filter the proposed filter is composed of polynomials in different orders which can fit normal orbit trajectory well. A memoryless polynomial filter (MLF) is designed first. The designed memoryless polynomial filter can be separated into a linearization filter and a FIR filter. Analogous to linear LMS adaptive filter a LMS adaptive algorithm is derived for the memoryless polynomial filter which is called Memoryless polynomial LMS adaptive filter (MLPLMS adaptive filter). Experiments show that the proposed filter has better performance than that of a normal LMS filter on orbit tracking. 2009 IEEE.