中国科学院机构知识库网格系统: 检索

Robust Sparse Bayesian Two-Dimensional Direction-of-Arrival Estimation with Gain-Phase Errors 期刊论文 OAI收割
SENSORS, 2023, 卷号: 23, 期号: 23, 页码: 17
作者: Jin, Xu; Wang, Xuhu; Hou, Yujun; Hao, Siyuan; Wang, Xinjie

|

收藏 | 浏览/下载：20/0 | 提交时间：2024/04/07

two-dimensional direction-of-arrival (2D DOA) gain-phase errors sparse signal reconstruction sparse Bayesian learning L-shaped array

Timesaving phase retrieval approach based on difference map normalization and fast iterative algorithm 期刊论文 OAI收割
Optics and Lasers in Engineering, 2019, 卷号: 121, 页码: 18-28
作者: Y.Zhang; X.B.Tian; R.G.Liang

|

收藏 | 浏览/下载：30/0 | 提交时间：2020/08/24

Phase shifting algorithm,Iterative algorithm,Difference ma,normalization,Phase shift,Interferometry,principal component analysis,wave-front reconstruction,shifting,interferometry,extraction,interferograms,vibration,errors,Optics

Error analysis of the piston estimation method in dispersed fringe sensor 期刊论文 OAI收割
Chinese Physics B, 2017, 卷号: 26, 期号: 3, 页码: 039501
作者: Li, Yang; Wang, Sheng-Qian; Rao, Chang-Hui

|

收藏 | 浏览/下载：30/0 | 提交时间：2018/11/20

Adaptive optics - Errors - Interferometers - Phase measurement - Pistons - Telescopes

Multi-spectral modulation detection of co-phasing errors for sparse-optical-synthetic-aperture systems 期刊论文 OAI收割
Proceedings of SPIE: 8th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, 2016, 卷号: 9682, 页码: 96820W
作者: Dong, Li; Peng, Qi; Ma, Haotong; Xie, Zongliang; Wang, Zhipeng

|

收藏 | 浏览/下载：25/0 | 提交时间：2018/06/14

Errors Manufacture Mirrors Modulation Optical Systems Optical Testing Phase Modulation Spectroscopy Telescopes

Signal-to-noise ratio analysis of X-ray grating interferometry with the reverse projection extraction method 期刊论文 OAI收割
JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA, JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA, 2014, 2014, 卷号: 196, 196, 期号: SI, 页码: 75-79, 75-79
作者: Wu, Z; Wang, ZL; Gao, K; Wang, DJ; Wang, SH

|

收藏 | 浏览/下载：20/0 | 提交时间：2016/04/08

Grating-based X-ray phase contrast imaging Photon statistics Mechanical errors Signal-to-noise ratio Grating-based X-ray phase contrast imaging Photon statistics Mechanical errors Signal-to-noise ratio

Research on satellite platform vibration compensation technology for space optical communication (EI CONFERENCE) 会议论文 OAI收割
2012 International Meeting on Opto-Electronics Engineering and Materials Research, OEMR 2012, July 27, 2012 - July 29, 2012, Shenyang, Liaoning, China
Han C.; Li X.

收藏 | 浏览/下载：22/0 | 提交时间：2013/03/25

The piezo-electric steering control system is used to compensate the vibration of satellite platform. The mathematical model of piezo-electric steering system is built. The adaptive controller based on improved LMS filter algorithm is designed according to this system characteristic. The adaptive delay filter is designed to solve slow convergence speed problem of traditional algorithm. Meanwhile the adaptive delay filter can also compensate phase delay of control circuit. The adaptive deviation filter is introduced and it effectively compensates the vibration deviation which is low frequency and high amplitude. The experimental results show that the remained errors are rad which meets space optical communication requirement and proves that this control scheme is valid and feasible. (2012) Trans Tech Publications Switzerland.

Physical layer design for free space optical communication (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Control Engineering and Communication Technology, ICCECT 2012, December 7, 2012 - December 9, 2012, Shenyang, Liaoning, China
作者: Wang H.; Zhang Q.; Guo J.; Guo J.; Wang H.

收藏 | 浏览/下载：30/0 | 提交时间：2013/03/25

A small size Free Space Optical Communication System is introduced including the hardware and the hardware specified physical layer protocol. In detail the rapid synchronization method to reduce the handshake bandwidth requirement is demonstrated. The hardware of the system includes the laser driver system the signal amplifying and shaping system the data interface system. The hardware specified physical layer protocol is used to interface the outer data serialize and deserialize the data stream check transmission errors and schedule the data transmission. The overall system is a FIFO-like system and the user can use it as if he's operating a FIFO. The system is designed mainly for terrestrial FSO link whose signal channel is the atmosphere. Due to the complex composition and activity of the atmosphere this signal channel brings in great influence on the transmitting laser in it for example the absorption and scattering of the atmosphere molecules and aerosols the scintillation of received laser power caused by the turbulence of the atmosphere all of which results in a much higher Bit Error Rate (BER) of the communication system than wired communication systems leading to frequent resynchronization. In our system the sampling clock is generated locally using multi-phase sampling technique rather than PLLbased clock recovery which helps to rapid synchronization. 2012 IEEE.

Analysis of measuring errors for the visible light phase-shifting point diffraction interferometer (EI CONFERENCE) 会议论文 OAI收割
2010 OSA-IEEE-COS Advances in Optoelectronics and Micro/Nano-Optics, AOM 2010, December 3, 2010 - December 6, 2010, Guangzhou, China
作者: Zhang Y.

收藏 | 浏览/下载：15/0 | 提交时间：2013/03/25

In order to improve the measuring accuracy of the visible light phase-shifting point diffraction interferometer (PS/PDI) for the extreme ultraviolet lithography (EUVL) aspheric mirrors the main measuring errors will be discussed in this paper. At first the elementary configuration and measuring principle of the visible light phase-shifting point diffraction interferometer are introduced briefly then the different errors which are possible to affect the measuring result are summed up the errors include PZT phase-shifting error detector nonlinearity error detector quantization error wavelength instability error and intensity instability error of the laser source vibration error air refractivity instability error and so on. Through detailed analysis and simulation the magnitude of these errors can be obtained. By analysing the reasons which cause these errors and the relationship between these errors and interferometer configuration parameters some methods are put forward to avoid or restrain these errors accordingly.

Method for recovering dynamic position of photoelectric encoder (EI CONFERENCE) 会议论文 OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 19, 2008 - November 21, 2008, Chengdu, China
作者: Sun Y.; Liu Y.-S.; Liang L.-H.; Sun Y.; Wan Q.-H.

收藏 | 浏览/下载：16/0 | 提交时间：2013/03/25

This paper presents a method to recover dynamic position of photoelectric encoder. While working at dynamic state original outputs of the photoelectric encoder are in theory two sine or triangular signals with a phase difference of /2. However there are still deviations of actual output signals. Interpolating on the basis of this deviation signal will result in interpolation errors. In dynamic state true original signal data obtained by data acquisition system is a time equation. Through processing these data by data equiangular and harmonic analysis the equation will be converted from time domain to position domain and an original position equation can be formed. Then the interpolation errors also can be obtained. By this method the interpolation errors can be checked in dynamic state and it can also provide electric interpolation basis so that to improve dynamic interpolation precision of the encoder. Software simulation and experimental analysis all prove the method effective. This method is he basis in theory for precision checking and calibration in motion. 2009 SPIE.

The analysis and design of low velocity estimation based on observer (EI CONFERENCE) 会议论文 OAI收割
2009 IEEE International Conference on Automation and Logistics, ICAL 2009, August 5, 2009 - August 7, 2009, Shenyang, China
作者: Wang D.; Zhang S.

收藏 | 浏览/下载：34/0 | 提交时间：2013/03/25

Low velocity servo system needs precision velocity estimation. An observer for low velocity estimation was proposed in this paper. First the source of low velocity estimation errors and the shortcomings of the single period difference were analyzed. The relationship between the estimation accuracy and estimator's frequency characteristics was concluded. Then the structure of the observer was proposed. Frequency characteristics were used to design the compensator which can stabilize the observer. The stability of the observer was also discussed. At last the observer's estimation accuracy was evaluated through a quantitative comparison. The results of simulation and experiment have shown that the quantized error in velocity estimation decreases dramatically when a velocity observer is used. Compared with some commonly-used estimators the phase lag accompanying the observer is much less. 2009 IEEE.