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A robust vector tracking loop structure based on potential bias analysis

Chinese Journal of Aeronautics 2024年第4期37卷 405-420页

作者： Qiongqiong JIA Yiran LUO Bing XU Li-Ta HSU Renbiao WU Tianjin Key Lab for Advanced Signal Processing Civil Aviation University of ChinaTianjin 300300China Interdisciplinary Division of Aeronautical and Aviation Engineering The Hong Kong Polytechnic University999077Hong KongChina Department of Geomatics Engineering University of CalgaryCalgary T2N1N4Canada

This paper proposes a robust vector tracking loop structure based on potential bias analysis. The influence of four kinds of biases on the existing two implementations of Vector Tracking Loops(VTLs) is illustrated by theoretical analysis and numerical simulations, and the following findings are obtained. Firstly, the initial user state bias leads to steady navigation solution bias in the relative VTL, while new measurements can eliminate it in the absolute VTL. Secondly, the initial code phase bias is transferred to the following navigation solutions in the relative VTL, while new measurements can eliminate it in the absolute VTL. Thirdly, the user state bias induced by erroneous navigation solution of VTLs can be eliminated by both of the two VTLs. Fourthly,the multipath/NLOS likely affects the two VTLs, and the induced tracking bias in the duration of the multipath/NLOS would decrease the performance of VTLs. Based on the above analysis,a robust VTL structure is proposed, where the absolute VTL is selected for its robustness to the two kinds of initialization biases;meanwhile, the instant bias detection and correction method is used to improve the performance of VTLs in the duration of the multipath/NLOS. Numerical simulations and experimental results verify the effectiveness of the proposed robust VTL structure.

关键词： Global Navigation Satellite System(GNSS) Vector Tracking Loop(VTL) multipath Non-Line-of-Sight(NLOS) Tracking bias propagation Least Absolute Shrinkage and Selection Operator(LASSO)

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multipath matching pursuit using a cross-validation technique for sparse direction-of-arrival estimation with an acoustic vector array

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Chinese Journal of Acoustics 2023年第2期42卷 153-170页

作者： TAN Peng HU Bo ZHANG Youwen WU Yuquan YANG Desen Acoustic Science and Technology Laboratory Harbin Engineering UniversityHarbin 150001 Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001 College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001 School of Electronics and Information Jiangsu University of Science and TechnologyZhenjiang 212100 Science and Technology on Integrated Information System Laboratory Institute of SoftwareChinese Academy of SciencesBeijing 100190

High-resolution direction-of-arrival(DOA)estimations and the starboard ambiguity of moving underwater targets have always been key issues in underwater acoustic array signal processing.Compared with sound pressure arrays,vector arrays have natural advantages with respect to solving the starboard ambiguity problem and obtaining higher processing gains.Traditional high-resolution DOA estimation methods such as Capon have disadvantages such as being unable to resolve coherent sources,requiring multiple snapshot processing,and being sensitive to array manifold errors.High-resolution DOA estimation and the starboard ambiguity of moving underwater targets have always been challenging research topics.On one hand,maneuvering underwater targets reduce the coherence time of the received signals,which ultimately leads to poor performance when using high-resolution DOA estimation technologies based on the covariance matrix of the received signal.On the other hand,traditional DOA estimation technologies based on sound pressure arrays have the problem of port and starboard ambiguity,which can be solved by maneuvering the sonar platform.However,maneuvering the sonar platform can impair the coherence of the received signal,on which some algorithms rely.This approach greatly limits the combat effectiveness and performance of the platform.Given the aforementioned problems and taking advantage of the target sparsity,a cross-validation multipath matching pursuit technique based on the sparse DOA estimation of an acoustic vector array is proposed in this article for sonar observations.The proposed algorithm uses cross-validation technology to achieve a sparse DOA estimation with an unknown number of targets in a sonar observation scene.Compared with the conventional acoustic vector array-based Capon algorithm,the proposed algorithm can achieve a sparse DOA estimation and high-resolution capability with small numbers of snapshots or even single snapshots.The effectiveness of the proposed algorithm is verified via simulations and sea t

关键词： multipath estimation underwater

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multipath effects on vector tracking algorithm for GNSS signal

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Science China(Information Sciences) 2014年第10期57卷 145-157页

作者： LUO Yu WANG YongQing WU SiLiang WANG Pai School of Information and Electronics Beijing Institute of Technology

The vector tracking algorithm uses a single extended Kalman filter(EKF) to predict the time-delays and the Doppler deviations of the GNSS signal, while also estimating the user’s position, velocity, and clock state. In this paper, the effects of multipath on the tracking performance of the vector delay / frequency lock loop(VDFLL) is studied for better application in the multipath environment. The error expressions of the measurements are given in theory. The tracking error caused by multipath is reduced by VDFLL, which is proved by the tracking error of VDFLL through a new iterating method. The theoretical analysis is verified by the Monte Carlo simulation.

关键词： GNSS multipath VDFLL EKF tracking error

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An Improved Key Generation Scheme Based on multipath Channel Measurements

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Chinese Journal of Electronics 2017年第1期26卷 185-191页

作者： HAN Yuanzhi HU Aiqun School of Information Science and Engineering Southeast University

Channel reciprocity is a vital component for the key generation from multipath channels. In this paper, we introduce the effect of delay between measures on the channel reciprocity, build an Autoregression(AR)model to approximate time-varying channel measurements and apply a linear prediction method to reduce the measurement errors and to enhance the dependency between measurements of two communication parties. In the following bit conversion, we propose a novel quantization scheme named the Probability distance method(PDM) and compare its performance with other existing methods theoretically. The simulation results show that the optimal solution to the linear prediction problem can effectively increase the channel reciprocity in the assumed channel models.The proposed PDM can achieve a lower disagreement rate with acceptable costs.

关键词： Physical layer security Key generation Linear prediction multipath

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Spectral transformation-based technique for reducing effect of limited pre-correlation bandwidth in the GNSS receiver filter in presence of noise and multipath

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Journal of Systems Engineering and Electronics 2020年第2期31卷 252-265页

作者： TITOUNI Salem ROUABAH Khaled ATIA Salim FLISSI Mustapha MEZAACHE Salaheddine BOUHLEL Mohamed Salim Electronics and Advanced Telecommunications Laboratory of Electronics Department University of Mohamed El Bachir El IbrahimiBordj Bou Arreridj 34031Algeria Sciences of Electronics Technologies of Information and Telecommunications Research UnitHigher Institute of Biotechnology of SfaxSfax 3038Tunisia

This paper proposes an efficient scheme to reduce the pre-correlation bandwidth effect in the global navigation satellite system(GNSS)receiver filtering process.It is mainly based on the application of a spectral transformation to the satellite-emitted signal that effectively reduces its band.At the receiver's end,this operation causes the spreading of noise over a much wider band than that used by the radio frequency stage.Consequently,the resulting auto-correlation function in the acquisition process acquires properties that enhance considerably the performance of the receiver in the presence of the multipath and noise disturbing phenomena.The simulation results demonstrate that the proposed method is a plausible solution for both multipath and noise problems in the GNSS applications for any limited value of the pre-correlation bandwidth in the receiver filter.

关键词： precorrelation bandwidth spectral transformation multipath noise

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Cross-correlation function based multipath mitigation technique for cosine-BOC signals

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Journal of Systems Engineering and Electronics 2013年第5期24卷 742-748页

作者： Huihua Chen Weimin Jia Minli Yao Department of Electronic & Information Engineering The Secord Artillery Engineering University

We propose a new multipath mitigation technique based on cross-correlation function for the new cosine phased binary off-set carrier （cosine-BOC） modulated signals, which will most likely be employed in both European Galileo system and Chinese Compass system. This technique is implemented to create an optimum cross-correlation function via designing the modulated symbols of the local signal. And the structure of the code tracking loop for cosine-BOC signals is quite simple including only two real correlators. Results demonstrate that the technique efficiently eliminates the ranging errors in the medium and long multipath regions with respect to the conventional receiver correlation techniques.

关键词： multipath cosine phased binary offset carrier （cosine- BOC） GaJiJeo Compass.

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A multipath resource updating approach for distributed controllers in software-defined network.

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Science China(Information Sciences) 2016年第9期59卷 227-236页

作者： Xiaochun WU Chunming WU Changting LIN Qiang WU Bin WANG Computer Science College Zhejiang University Institute of Network and Communication Engineering Zhejiang Gongshang University ZTE Central R&D ZTE Corporation

Finding effective ways to collect the usage of network resources in all kinds of applications to ensure a distributed control plane has become a key requirement to improve the controller’s decision making performance.This paper explores an efficient way in combining dynamic Net View sharing of distributed controllers with the behavior of intra-service resource announcements and processing requirements that occur in distributed controllers, and proposes a rapid multipathing distribution mechanism. Firstly, we establish a resource collecting model and prove that the prisoner’s dilemma problem exists in the distributed resource collecting process in the Software-defined Network(SDN). Secondly, we present a bypass path selection algorithm and a diffluence algorithm based on Q-learning to settle the above dilemma. At last, simulation results are given to prove that the proposed approach is competent to improve the resource collecting efficiency by the mechanism of self-adaptive path transmission ratio of our approach, which can ensure high utilization of the total network we set up.

关键词： multipath Pareto optimal Q-learning

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Novel adaptive Hatch filter to mitigate the effects of ionosphere and multipath on LAAS

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Journal of Systems Engineering and Electronics 2010年第6期21卷 1046-1053页

作者： Lin Zhao, Liang Li, Ming Sun, and Xiaoxu Wang College of Automation, Harbin Engineering University, Harbin 150001, P. R. China College of Automation Harbin Engineering University Harbin 150001 P. R. China

It has been proven that carrier smoothing and differential global positioning system （DGPS） are effective to improve the accuracy of pseudorange by reducing the noise in it and eliminating almost all the common mode errors between the ground station and user. However, another issue coming with local area augmentation system （LAAS） is how to find an adaptive smoothing window width to minimize the error on account of ionosphere delay and multipath. Based on the errors analysis in carrier smoothing process, a novel algorithm is formulated to design adaptive Hatch filter whose smoothing window width flexibly varies with the characteristic of ionosphere delay and multipath in the differential carrier smoothing process. By conducting the simulation in LAAS and after compared with traditional Hatch filers, it reveals that not only the accuracy of differential correction, but also the accuracy and the robustness of positioning results are significantly improved by using the designed adaptive Hatch filter.

关键词： Hatch filter adaptive ionosphere delay multipath differential correction local area augmentation system.

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Increasing multicast transmission rate with localized multipath in software-defined networks

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Frontiers of Computer Science 2019年第2期13卷 413-425页

作者： Siyuan TANG Bei HUA School of Computer Science and Technology University of Science and Technology of China (USTC) Hefei 230027 China Suzhou Institute for Advanced Study USTC Suzhou 215123 China

Network layer multicast is a highly efficient oneto ?many transmission mode. Data rates supported by different group members may differ if these members are located in different network environments. Currently there are roughly two types of methods solving the problem, one is limiting the data rate so that every group member can sustain transmissions, and the other is building multiple trees to increase the provision of network bandwidth. The former is inefficient in bandwidth usage, and the latter adds too many states in the network, which is a serious problem in Software-Defined Networks. In this paper, we propose to build localized extra path(s) for each bottleneck link in the tree. By providing extra bandwidth to reinforce the bottleneck links, the overall data rate is increased. As extra paths are only built in small areas around the bottleneck links, the number of states added in the network is restrained to be as small as possible. Experiments on Mimnet verify the effectiveness of our solution.

关键词： software-defined networking network layer multicast localized multipath

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An adaptive path selection model for WSN multipath routing inspired by metabolism behaviors

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Science China(Information Sciences) 2015年第10期58卷 133-147页

作者： GONG WeiBing YANG XiaoLong ZHANG Min LONG KePing School of Computer & Communication Engineering University of Science and Technology Beijing

In multipath routing of wireless sensor network(WSN), greedy path selection is always prone to cause path oscillation(frequent path changes) between each couple of sensor and sink nodes. To alleviate the side effect, we propose an adaptive path selection model(called a WSN path selection model based on the adaptive response by attractor selection(ARAS) model(WARAS)) inspired by metabolism behaviors of Escherichia Coli.The model consists of two main features. The first one is a new formula for a parameter called path-activity used to indicate adaptation goodness of multipath traffic transmission in dynamic network environments, which is inversely proportional to absolute value of difference between current path quality and best path quality.The second one is a novel attractor expression for attractors of multi-attractor equations to concretely specify stochastic effect of noise items in the equations on the path selection. Then, in an experimental WSN scenario composed of many source nodes and their shared neighbor nodes, we validate a dynamic-adaptive selection characteristic of the WARAS on distributing loads of the neighbor nodes. Subsequently, we design a path quality probe scheme in a multipath ad hoc on-demand distance vector routing(AODV) protocol. Compared with the greedy path selection through the path quality probe scheme, simulation results show the WARAS can perform better on reducing network delay and the path oscillation.

关键词： WSN multipath path selection metabolism behaviors of Escherichia Coli AODV

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