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7th International Symposium on Test Automation and Instrumentation, ISTAI 2018

作者： Sun, Peng Lu, Naiguang Dong, Mingli Wang, Jun Yan, Bixi Institute of Information Photonics and Optical Communication Beijing University of Posts and Telecommunications Beijing China Beijing Key Laboratory: Measurement and Control of Mechanical Electrical System Beijing Information Science and Technology University Beijing China School of Instrument Science and Optoelectronics Engineering Beijing Information Science and Technology University Beijing China

This study proposes an analytical method for calibrating and orienting online photogrammetric systems using a scale bar. The primary idea is building control lengths in the measurement volume by moving and rotating the scale bar and then conducting a self-calibration bundle adjustment using images of the control lengths. In this study, the five-point relative orientation method is used to provide estimations of the exterior camera parameters. Additionally, this study elaborates the model of the lengths constrained self-calibration bundle adjustment, the block computation algorithm and the accuracy assessment. This method obtains both the interior and the exterior orientation parameters of the two cameras, and provides spatial bar length reconstruction precision as the performance evaluation. Simulations are conducted to analyze the calibration accuracy and the results show that the method achieves comparable accuracy and precision against the state-of-the-art method. However, the method does not need steady and well distributed 3D points and is easy to operate. Real data experimental results show that the maximum length measurement error of this method in a volume of 5 m × 4 m × 2 m is © 2019 Institution of engineering and technology. All rights reserved.

关键词： Photogrammetry

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LOS/NLOS Channel Identification technology Based on CNN

LOS/NLOS Channel Identification Technology Based on CNN

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National Foundation for Science and technology Development Conference on Information and Computer Science (NICS)

作者： Fei Wang Zhan Xu Ruxin Zhi Jinhui Chen Peiyue Zhang School of Information and Communication Engineering Beijing Information Science and Technology University Beijing China Key Laboratory of Modern Measurement & Control Technology Beijing Information Science & Technology University Beijing China

ISBN: (数字)9781728151632

ISBN: (纸本)9781728151649

In the field of indoor positioning, ultra-wideband (UWB) communication technology is the key technology. But the errors caused by non-line of sight (NLOS) communication channels could greatly affect the positioning accuracy. Therefore, identifying the channel type can effectively avoid the above-mentioned errors, thereby helping to reduce the loss of positioning accuracy. This paper proposes a LOS/NLOS channel identification method by using a convolutional neural network (CNN) to identifying the impulse response figures of the channels. This method is capable of identifying four different types of channel impulse response figures and providing excellent identification accuracy. The results show that the accuracy of identifying LOS (0-4m), NLOS (0-4m), NLOS (4-10m) and extreme NLOS channel impulse response figures can reach 98.24%.

关键词： Delays Training Support vector machines IEEE 802.15 Standard Computer science Channel models

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Broadband Chaos Generation from Relaxation Oscillation-Free Polarization Mode of Vertical-Cavity Surface-Emitting Laser

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Guangxue Xuebao/Acta Optica Sinica 2025年第10期45卷

作者： Di, Chengzhen Liu, Qi Wang, Longsheng Zhao, Qingchun Guo, Yuanyuan Chang, Pengfa Jia, Zhiwei Wang, Anbang Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education Taiyuan University of Technology Shanxi Taiyuan030024 China College of Electronic Information and Optical Engineering Taiyuan University of Technology Shanxi Jinzhong030600 China Key Laboratory of Precision Measurement Physics Ministry of Shanxi Province Taiyuan University of Technology Shanxi Taiyuan030024 China School of Computer and Communication Engineering Northeastern University at Qinhuangdao Hebei Qinhuangdao066004 China Key Laboratory of Photonic Technology for Integrated Sensing and Communication Ministry of Education Guangdong University of Technology Guangdong Guangzhou510006 China

Objective Secure communication based on chaotic lasers has gained significant attention in recent years due to its high speed and compatibility with existing fiber-optic networks. Vertical-cavity surface-emitting lasers (VCSELs) are promising candidates, offering a compact structure and low power consumption. However, VCSELs are constrained by chaotic bandwidth limitations induced by relaxation oscillations, which reduce the secure transmission rate. Existing methods for broadening the chaos bandwidth often rely on complex external perturbations, which may hinder system synchronization. We propose a simplified method for generating broadband chaos by utilizing the relaxation-oscillation-free polarization mode of VCSELs. Methods We present a novel approach for generating broadband chaos by utilizing the relaxation-oscillation-free polarization mode of VCSELs. The experimental setup (Fig. 1) employs a custom single-mode VCSEL with a wavelength of 1550 nm and no internal isolator. The laser is powered by a low-noise current source and is equipped with precise temperature control to ensure stable operation. Optical feedback is provided via a fiber mirror, with its intensity regulated by a variable optical attenuator. Polarization controllers are used to align the feedback polarization, directing X mode feedback to the X mode and Y mode feedback to the Y mode. The output signals are separated into X+Y, X, and Y modes using polarization beam splitters. The spectral, temporal, and dynamic properties of the VCSEL are analyzed using an optical spectrum analyzer, a high-speed oscilloscope, and an electrical spectrum analyzer. Key parameters, including bias current and feedback strength, are systematically varied and optimized to investigate their effects on chaos generation, with the aim of identifying the optimal conditions for achieving broadband chaos with the desired characteristics. Results and Discussions We begin with an in-depth analysis of the free-running VCSEL to e

关键词： Optical feedback

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Outage behaviors of NOMA-based satellite network over shadowed-rician fading channels

arXiv

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arXiv 2020年

作者： Yue, Xinwei Liu, Yuanwei Yao, Yuanyuan Li, Tian Li, Xuehua Liu, Rongke Nallanathan, Arumugam Key Laboratory of Modern Measurement & Control Technology Ministry of Education School of Information and Communication Engineering Beijing Information Science and Technology University Beijing100101 China School of Electronic Engineering and Computer Science Queen Mary University of London LondonE1 4NS United Kingdom 54th Research Institute of China Electronics Technology Group Corporation Shijiazhuang Hebei050081 China Beijing University of Posts and Telecommunications Beijing100876 China School of Electronic and Information Engineering Beihang University Beijing100191 China

This paper investigates the application of non-orthogonal multiple access (NOMA) to satellite communication network over Shadowed-Rician fading channels. The impact of imperfect successive interference cancellation (ipSIC) on NOMA-based satellite network is taken into consideration from the perspective of practical scenarios. We first derive new exact expressions of outage probability for the p-th terrestrial user and provide the corresponding asymptotic analysis results. The diversity order of zero and p are achieved by the p-th terrestrial user with ipSIC and perfect successive interference cancellation (pSIC), respectively. Finally, the presented simulation results show that: 1) On the condition of pSIC, the outage behaviors of NOMA-based satellite network are superior to that of orthogonal multiple access;2) With the value of residual interference increasing, the outage performance of terrestrial users with ipSIC is becoming worse seriously;and 3) Infrequent light shadowing of Shadowed-Rician fading brings the better outage probability compared to frequent heavy and average shadowing. Copyright © 2020, The Authors. All rights reserved.

关键词： Asymptotic analysis

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Prediction-based Optimal Distributed Filtering with communication Delay over Sensor Networks

Prediction-based Optimal Distributed Filtering with Communic...

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第三十八届中国控制会议

作者： Jun Hu Guo-Ping Liu Zidong Wang Hongxu Zhang School of Engineering University of South Wales Heilongjiang Provincial Key Laboratory of Optimization Control and Intelligent Analysis for Complex Systems Harbin University of Science and Technology CTGT center Harbin Institute of Technology Department of Computer Science Brunel University London School of Measurement and Communication Harbin University of Science and Technology

In this paper, the prediction-based distributed filtering problem is discussed for a class of time-varying stochastic systems with communication delay and different types of noises over sensor networks. The communication delay is characterized when the state estimations are transmitted between adjacent sensor nodes. In order to compensate the effects induced by the communication delay, the prediction-based idea is employed and then the active compensation estimation is provided when designing the time-varying distributed filter. In particular, both the prediction-based state estimation and its own innovation measurements are utilized in terms of the concerned sensor networks under given topological structure. Subsequently, a locally minimum upper bound of the filtering error covariance is given by determining the filter gain at each time step. Finally, the validity and advantages of the presented prediction-based distributed filtering method are illustrated by some simulations.

关键词： Time-varying stochastic systems Sensor networks Optimal distributed filtering communication delay Prediction compensation

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Humidity error compensating of MEMS gyros based on a daptive threshold denoising and RBF neural network 37

Humidity error compensating of MEMS gyros based on a daptive...

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37th Chinese control Conference, CCC 2018

作者： Xin-Wang, Wang Xiao-Lin, Shen Hui-Liang, Cao Bo-Wen, Deng North University of China School of Electrical and Control Engineering Taiyuan030051 China North University of China Science and Technology on Electronic Test Measurement Laboratory Taiyuan030051 China North University of China School of Information and Communication Engineering Taiyuan030051 China

ISBN: (纸本)9789881563941

The large random errors in a typical MEMS gyros under the ranges of relative humidity condition. In order to solve the large random error under the ranges of relative humidity, a method based on adaptive threshold denoising and neural network is proposed in this paper. Full relative humidity experiment is carried to test LSM6DS3 MEMS gyros. Then the adaptive threshold denoising is used to separate the drift error and drift data modeled with RBF neural network. The experimental results show the effectiveness of the method, and it is of great significance in improving the performance of MEMS gyros. © 2018 Technical Committee on control Theory, Chinese Association of Automation.

关键词： Random errors

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Secure communications in a unified non-orthogonal multiple access framework

arXiv

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arXiv 2019年

作者： Yue, Xinwei Liu, Yuanwei Yao, Yuanyuan Li, Xuehua Liu, Rongke Nallanathan, Arumugam School of Information and Communication Engineering Key Laboratory of Modern Measurement & Control Technology Ministry of Education Beijing Information Science and Technology University Beijing100101 China School of Electronic Engineering and Computer Science Queen Mary University of London LondonE1 4NS United Kingdom School of Electronic and Information Engineering Beihang University Beijing100191 China

This paper investigates the impact of physical layer secrecy on the performance of a unified non-orthogonal multiple access (NOMA) framework, where both external and internal eavesdropping scenarios are examined. The spatial locations of legitimate users (LUs) and eavesdroppers are modeled by invoking stochastic geometry. To characterize the security performance, new exact and asymptotic expressions of secrecy outage probability (SOP) are derived for both code-domain NOMA (CD-NOMA) and power-domain NOMA (PD-NOMA), in which imperfect successive interference cancellation (ipSIC) and perfect SIC (pSIC) are taken into account. For the external eavesdropping scenario, the secrecy diversity orders by a pair of LUs (the n-th user and m-th user) for CD/PD-NOMA are obtained. Analytical results make known that the diversity orders of the n-th user with ipSIC/pSIC for CD-NOMA and PD-NOMA are equal to zero/ K and zero/one, respectively. The diversity orders of the m-th user are equal to K/one for CD/PD-NOMA. For the internal eavesdropping scenario, we examine the analysis of secrecy diversity order and observe that the m-th user to wiretap the n-th user with ipSIC/pSIC for CD-NOMA and PDNOMA provide the diversity orders of zero/K and zero/one, respectively, which is consistent with external eavesdropping scenario. Numerical results are present to confirm the accuracy of the analytical results developed and show that: i) The secrecy outage behavior of the n-th user is superior to that of the m-th user;ii) By increasing the number of subcarriers, CD-NOMA is capable of achieving a larger secrecy diversity gain compared to PD-NOMA. Copyright © 2019, The Authors. All rights reserved.

关键词： Geometry

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Geometric statistics based modeling of dual polarized satellite mobile MIMO channel 35

Geometric statistics based modeling of dual polarized satell...

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35th AIAA International communications Satellite Systems Conference, ICSSC 2017

作者： Chen, Ma Jingchao, Wang Mingchuan, Yang Xirui, Xian Information and Communication Engineering Communication Research Center Harbin Institute of Technology Harbin China Information and Communication Engineering Institute of China Electronic System Engineering Company Beijing100141 China Measurement and Control Technology Measurement and Control Technology and Instrument Harbin Institute of Technology Harbin China

ISBN: (数字)9781624105180

ISBN: (纸本)9781624105180

MIMO technique can improve the spectral efficiency and increase the system capacity of the satellite mobile communication system, and the modeling of dual-polarized satellite mobile MIMO channel has been a hotspot issue. In order to take the advantage of the low complexity of the statistics channel model and the high acuuracy of the geometric model, geometric statistics based modeling theory of dual-polarized satellite mobile MIMO channel is proposed in this paper. The geometric statistics based model applies ray tracing method to each MIMO path, and calculate the parameters of the rays with statistical methods. The simulation results of the first and the second order statistical characteristics are given in the paper, and the geometric statistics model of dual-polarized satellite mobile MIMO channel is verified. Also, the conclusion that the model can improve the accuracy of the simulation of dual-polarized satellite mobile MIMO channel effectively is drawn. © 2017, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Satellites

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Humidity Error Compensating of MEMS Gyros Based on A daptive Threshold Denoising and RBF Neural Network

Humidity Error Compensating of MEMS Gyros Based on A daptive...

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第37届中国控制会议

作者： Wang Xin-wang Shen Xiao-lin Cao Hui-liang Deng Bo-wen School of Electrical and Control Engineering North University of China IEEE Science and Technology on Electronic Test & Measurement Laboratory North University of China School of Information and Communication Engineering North University of China

The large random errors in a typical MEMS gyros under the ranges of relative humidity *** order to solve the large random error under the ranges of relative humidity,a method based on adaptive threshold denoising and neural net work is proposed in this *** relative humidity experiment is carried to test LSM6DS3 MEMS *** the adaptive threshold denoising is used to separate the drift error and drift data modeled with RBF neural *** experimental res ults show the effectiveness of the method,and it is of great significance in improving the performance of MEMS gyros.

关键词： MEMS gyroscopes relative humidity adaptive threshold function random error model error compensations radial basis function neural network

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Event-triggered Resilient Filtering for Time-varying Systems with Randomly Occurring Nonlinearity and Missing measurements

Event-triggered Resilient Filtering for Time-varying Systems...

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第30届中国控制与决策会议

作者： Ming Gao Jun Hu Hongxu Zhang Department of Mathematics Harbin University of Science and Technology School of Engineering University of South Wales School of Measurement and Communication Harbin University of Science and Technology The Higher Educational Key Laboratory for Measuring & Control Technology and Instrumentations of Heilongjiang Province Harbin University of Science and Technology

This paper studies the event-triggered resilient filtering problem for a class of nonlinear systems with randomly occurring nonlinearity and missing measurements. Both the phenomena of the randomly occurring nonlinearity and the missing measurements are described by Bernoulli distributed random variables, where the occurrence probabilities could be uncertain. The event-triggered communication mechanism is introduced to save the network bandwidth during the data transmissions through the network. Additionally, the filter gain perturbations are characterized by employing the norm bounded uncertainties. The aim of the paper is to develop a robust event-triggered resilient filtering algorithm against the randomly occurring nonlinearity and missing measurements. Note that the analytical expressions of the filtering error covariance cannot be computed directly. Consequently, we derive its upper bound as an alternative way and subsequently minimize such an upper bound by properly designing the filter gain at each time step. Finally, an illustrative example is presented to show the effectiveness of the provided filtering algorithm.

关键词： Time-varying systems event-triggered mechanism randomly occurring nonlinearity missing measurements uncertain occurrence probabilities

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