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arXiv 2024年

作者： Yue, Shaohua Zeng, Shuhao Liu, Liang Eldar, Yonina C. Di, Boya The State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Peking University Beijing100871 China The Department of Electronic and Information Engineering The Hong Kong Polytechnic University Hong Kong The Faculty of Mathematics and Computer Science Weizmann Institute of Science Rehovot7610001 Israel

Holographic MIMO communications, enabled by large-scale antenna arrays with quasi-continuous apertures, is a potential technology for spectrum efficiency improvement. However, the increased antenna aperture size extends the range of the Fresnel region, leading to a hybrid near-far field communication mode. The users and scatterers randomly lie in near-field and far-field zones, and thus, conventional far-field-only and near-field-only channel estimation methods may not work. To tackle this challenge, we demonstrate the existence of the power diffusion (PD) effect, which leads to a mismatch between the hybrid-field channel and existing channel estimation methods. Specifically, in far-field and near-field transform domains, the power gain of one channel path may diffuse to other positions, thus generating fake paths. This renders the conventional techniques unable to detect those real paths. We propose a PD-aware orthogonal matching pursuit algorithm to eliminate the influence of the PD effect by identifying the PD range, within which paths diffuse to other positions. PD-OMP fits a general case without prior knowledge of near-field and far-field path numbers and the user’s location. The computational complexity of PD-OMP and the Cramér-Rao Lower Bound for the sparse-signal-recovery-based channel estimation are also derived. Simulation results show that PD-OMP outperforms state-of-the-art hybrid-field channel estimation methods. © 2024, CC BY-NC-ND.

关键词： Channel estimation

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Hybrid WDM and Optical-CDMA over Multi-Mode Fiber Transmission System based on Optical Vortex 5

Hybrid WDM and Optical-CDMA over Multi-Mode Fiber Transmissi...

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5th International Conference on Electronic Design, ICED 2020

作者： Ghazi, Alaan Aljunid, S.A. Zulkarnain Syed Idrus, Syed Endut, R. Rashidi, C.B.M. Ali, N. Al-Dawoodi, Aras Fakhrudeen, Ahmed M. Fareed, Alaa Sharma, Teena School of Human Development and Techno-communication University Malaysia Perlis Malaysia School of Computer and Communication Engineering University Malaysia Perlis Malaysia Computer Science Department College of Computer Science and Information Technology Kirkuk University Iraq Networks Department College of Computer Science and Information Technology Kirkuk University Iraq Computer Technical Engineering Alkitab University Iraq School of Computing University Utara Malaysia Malaysia Centre of Excellence Universiti Malaysia Perlis Malaysia Universiti Malaysia Perlis Perlis Malaysia Department of Electronics and Communication Engineering Malviya National Institute of Technology Jaipur India

The optical vortex has recently attracted scholars to implement it in optical tweezers, microscopy, optical communications, quantum information processing, optical trapping, and laser machining. Optical vortex beam applied classically that can be transferred to the transverse amplitude of a heralded single-photon, and optical vortex possesses a helical wavefront and carries orbital angular momentum. In this study, Optical vortex is applied in optical-CDMA (optical code-division multiple-access) in conjunction with WDM (wavelength division multiplexing). This mechanism aims to increase the capacity and security in optical communication significantly. The implementation of Laguerre-Gaussian (LG) modes with optical vortex based on one dimension zero cross-correlation (ZCC) code shows that mode coupling reduces effectively. Consequently, a positive increase in channel performance and response. Accordingly, the LG modes based on the 1D-ZCC code are investigated and propagated over multi-mode fiber (MMF) based on an optical vortex, which also substantially reduces channel effects. Consequently, all these attributes combined will result in a hybrid WDM-Optical-CDMA with an optical vortex system over MMF. © 2021 Published under licence by IOP Publishing Ltd.

关键词： Optical tweezers

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AEMIM: Adversarial Examples Meet Masked Image Modeling

arXiv

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arXiv 2024年

作者： Xiang, Wenzhao Liu, Chang Su, Hang Yu, Hongyang Beijing100190 China Peng Cheng Laboratory Shenzhen10587 China University of the Chinese Academy of Sciences Beijing100049 China Institute of Image Communication and Networks Engineering Department of Electronic Engineering Shanghai Jiao Tong University Shanghai200240 China Department of Computer Science and Technology Tsinghua University Beijing100084 China

Masked image modeling (MIM) has gained significant traction for its remarkable prowess in representation learning. As an alternative to the traditional approach, the reconstruction from corrupted images has recently emerged as a promising pretext task. However, the regular corrupted images are generated using generic generators, often lacking relevance to the specific reconstruction task involved in pre-training. Hence, reconstruction from regular corrupted images cannot ensure the difficulty of the pretext task, potentially leading to a performance decline. Moreover, generating corrupted images might introduce an extra generator, resulting in a notable computational burden. To address these issues, we propose to incorporate adversarial examples into masked image modeling, as the new reconstruction targets. Adversarial examples, generated online using only the trained models, can directly aim to disrupt tasks associated with pre-training. Therefore, the incorporation not only elevates the level of challenge in reconstruction but also enhances efficiency, contributing to the acquisition of superior representations by the model. In particular, we introduce a novel auxiliary pretext task that reconstructs the adversarial examples corresponding to the original images. We also devise an innovative adversarial attack to craft more suitable adversarial examples for MIM pre-training. It is noted that our method is not restricted to specific model architectures and MIM strategies, rendering it an adaptable plug-in capable of enhancing all MIM methods. Experimental findings substantiate the remarkable capability of our approach in amplifying the generalization and robustness of existing MIM methods. Notably, our method surpasses the performance of baselines on various tasks, including ImageNet, its variants, and other downstream tasks. Copyright © 2024, The Authors. All rights reserved.

关键词： Image reconstruction

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Quantum qubit-optical cavity node: Effects of the temperature and coupling strengths on the cavity Fock-state distribution occupation probability and entropy of the subsystems using Dicke model

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Results in Physics 2025年 72卷

作者： Barhoumi, Mohamed Bassoli, Riccardo Fitzek, Frank H.P. Laboratory of Condensed Matter and Nanosciences (LMCN) Department of Physics Faculty of Sciences of Monastir University of Monastir Environment Street Monastir 5019 Tunisia Institut Supérieur d'Informatique et de Mathématiques de Monastir (ISIMM) University of Monastir Avenue de la Corniche Monastir 5000 Tunisia Deutsche Telekom Chair of Communication Networks Institute of Communication Technology Faculty of Electrical and Computer Engineering Technische Universität Dresden Dresden Germany Centre for Tactile Internet with Human-in-the-Loop (CeTI) Cluster of Excellence Dresden Germany Quantum Communication Networks (QCNets) research group Institute of Communication Technology Faculty of Electrical and Computer Engineering Technische Universität Dresden Dresden Germany

One of the most attractive systems for scalable quantum processing is the trapped atom in the optical cavity, which is easily manipulable with lasers. The qubit cavity system represents an attractive structure for quantum optics, with possibilities for applications in quantum detecting, quantum computation, and quantum communication. In addition, the investigation of the cavity-atom system under temperature is a fundamental concept in quantum optics and quantum information science. Here we continue in this quantum way, investigating different qubit(s)-cavity systems (where we increase the numbers of the qubit inside the optical cavity from one to four). Using the Dicke model, we calculate the probability of occupation of the ground state of the cavity 〈aˆ^†aˆ〉 and the expectation values 〈J_z〉 for each system. We find that these probabilities increase as the coupling strength C_s increases. This leads to reaching the ultra-strong coupling regime, which depends on the number of qubits. To describe the quantum state, we examine the cavity Wigner function WF as a function of the coupling strength C_s. Under the same parameters (e.g. C_s and the dissipation rates), we find that the separation of the quantum state in the WFs representation is different from one system to another. Furthermore, since understanding these kinds of systems is very important in order to improve the quantum network system, we study the entropy S of the subsystems (such as S of qubit) in each system. Also, we move beyond by studying the effect of the temperature on the Fock-state distribution occupation probability and entropy of the subsystems. Our results present another step to understanding the qubit(s)-cavity interaction to improve the performance of future quantum networks based on this system. Where the interplay between temperature, coupling strengths, and the Fock-state occupation probabilities contributes significantly to the understandi

关键词： Cavity Dicke model Quantum communication networks Quantum nodes Quantum state Qubit Qubit–cavity system Temperature

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Cybersecurity Using Hybrid Type Model for Classification Through SCO Optimization Technique

Cybersecurity Using Hybrid Type Model for Classification Thr...

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Computing, Power and communication Technologies (IC2PCT), IEEE International Conference on

作者： Jothi Prabha Appadurai Lekshmi S Raveendran R Latha E. Gangadevi M.Lawanya Shri Shilpa Gite Department of CSE(Networks) Kakatiya Institute of Technology and Science Warangal Telangana India Sathyabama Institute of Science and Technology Chennai India Electronics & Communication Engineering Saveetha Engineering College Saveetha Nagar Thandalam Chennai India Department of Computer Science Loyola College Chennai India SITE Vellore Institute of Technology Vellore India AIML department Symbiosis Institute of Technology Pune. Symbiosis International (Deemed University) Pune India

The effectiveness of Network Intrusion Detection Systems (NIDS) in recognizing complex attacks is hindered by evasion strategies like polymorphic malware and encrypted traffic. Vulnerabilities in NIDS algorithms are regularly exploited by cybercriminals, highlighting the dynamic relationship between changing attack tactics and cybersecurity defenses. An enhanced approach to strengthen Network Intrusion Detection Systems is suggested by this study. The methodology begins with a rigorous preprocessing phase that includes normalization functions to progress the accuracy and consistency of the input data. Optimizing the NIDS’s efficacy is the aim of the Single Candidate Optimization (SCO) algorithm for feature selection. We utilize a hybrid model that incorporates ANN, Wavelet Transform, and Long Short-Term Memory (LSTM) for the classification phase. This model is designed to identify sequential dependencies in the network traffic data that we have. A second iteration of the SCO is devoted to hyperparameter optimization in order to attain optimal model performance and to further optimize the model. For our review, we opted to use the BoT-IoT dataset because it is a gold standard in the field. The suggested approach demonstrates how SCO can improve hyperparameter optimization and feature selection, leading to a more accurate and cyberattack-resistant NIDS. Consequences from experiments and evaluations of performance demonstrate that the proposed strategy is effective; it achieves a remarkable 99.6 percent accuracy. This proves how successful it is in judgement to current representations, which is a significant step towards consolidation cybersecurity defenses against changing threat landscapes.

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Visible Light Positioning Based on a Single Luminaire: A Novel Visual Odometry Assisted Algorithm

Visible Light Positioning Based on a Single Luminaire: A Nov...

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IEEE International Conference on communications (ICC)

作者： Zhiyu Zhu Yang Yang Mingzhe Chen Caili Guo Yipeng Bai Beijing Key Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing China Department of Electrical and Computer Engineering Institute for Data Science and Computing University of Miami Coral Gables FL USA Beijing Laboratory of Advanced Information Networks School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing China

Visible light positioning (VLP) is a promising positioning technique, which, however, typically requires multiple luminaires to achieve accurate positioning. This paper proposes a novel visual odometry (VO) assisted visible light positioning algorithm (VO-VLP) in achieving positioning with only a single luminaire. In the considered model, a user equipped with a camera jointly uses geometric features in the captured images and coordinates information obtained via visible light communication (VLC) for positioning. The proposed VLP algorithm does not rely on any extra inertial measurement unit and relaxes the tilted angle limitation at the user. In particular, VO-VLP first uses the circle feature of a luminaire to obtain dual normal vectors of the luminaire. Then, the basic principle of VO is used to eliminate the wrong normal vector by exploiting the geometric features in two consecutive images captured when the user moves. Finally, the pose and location of the user are obtained by using an artificially marked point on the luminaire's contour. VO-VLP can achieve accurate positioning with only a single luminaire and a camera. Simulation results show that the proposed indoor positioning algorithm can achieve a 97th-percentile positioning accuracy of around 10 cm.

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MIMO-Terahertz in 6G Nano-communications:Channel Modeling and Analysis

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computers, Materials & Continua 2021年第1期66卷 263-274页

作者： Shahid Bashir Mohammed H.Alsharif Imran Khan Mahmoud A.Albreem Aduwati Sali Borhanuddin Mohd Ali Wonjong Noh Business Studies Department Namal InstituteMianwali42250Pakistan Department of Electrical Engineering College of Electronics and Information EngineeringSejong UniversitySeoul05006South Korea Department of Electrical Engineering University of Engineering and Technology PeshawarPeshawar814Pakistan Department of Electronics and Communications Engineering College of EngineeringA’Sharqiyah UniversityIbraOman Wireless and Photonics Networks Research Centre of Excellence Department of Computer and Communication Systems EngineeringUnversiti Putra MalaysiaSelangor43400Malaysia School of Software Hallym UniversityHallymdaehak-gilChunchoen-si24252South Korea

With the development of wireless mobile communication technology,the demand for wireless communication rate and frequency increases year by *** wireless mobile communication frequency tends to be saturated,which demands for new ***(THz)communication has great potential for the future mobile communications(Beyond 5G),and is also an important technique for the high data rate transmission in spatial information *** communication has great application prospects in military-civilian integration and coordinated *** China,important breakthroughs have been achieved for the key techniques of THz high data rate communications,which is practically keeping up with the most advanced technological level in the ***,further intensifying efforts on the development of THz communication have the strategic importance for China in leading the development of future wireless communication techniques and the standardization process of Beyond *** paper analyzes the performance of the MIMO channel in the Terahertz(THz)band and a discrete mathematical method is used to propose a novel channel ***,a channel capacity model is proposed by the combination of path loss and molecular absorption in the THz band based on the CSI at the *** results show that the integration of MIMO in the THz band gives better data rate and channel capacity as compared with a single channel.

关键词： Wireless communication 6G mobile communication terahertz communication MIMO channel modeling

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Verification of Channel Reciprocity in Long-Range Turbulent FSO Links 19

Verification of Channel Reciprocity in Long-Range Turbulent ...

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19. ITG-Fachtagung Photonische Netze - 19th ITG Conference on Photonic networks

作者： Parthasarathy, Swaminathan Giggenbach, Dirk Fuchs, Christian Mata-Calvo, Ramon Barrios, Ricardo Kirstädter, Andreas WesslingD-82234 Germany Institute of Communication Networks and Computer Engineering University of Stuttgart StuttgartD-70569 Germany

ISBN: (纸本)9783800746842

High-Altitude Platforms/High-Altitude Pseudo Satellites (HAPs) will extend Internet access to currently uncovered regions. Free-Space Optical (FSO) links will interconnect HAPs over long distances through the stratosphere. Their Forward Error Correction has to be carefully adapted to the atmospheric scintillation channel. Long delay impairs the exploitation of receiver-based channel state information (CSI). Only inherent CSI provided by channel reciprocity allows in time control. Investigation results of this fading-signal correlation phenomenon over long distances however have not yet been reported. Therefore, we experimentally study this effect in a long-range (63km) monostatic bidirectional atmospheric FSO link for a wide range of parameters. Numerical phase-screen simulations of the transmission scenario confirm the results. © 2020 Photonische Netze - 19. ITG-Fachtagung. All rights reserved.

关键词： Channel state information

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Simulative performance analysis of arq schemes for free-space optical inter-HAP channel model 16

Simulative performance analysis of arq schemes for free-spac...

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16. ITG-Fachtagung Photonische Netze - 16th ITG Conference on Photonic networks

作者： Parthasarathy, Swaminathan Kirstädter, Andreas Giggenbach, Dirk WesslingD-82234 Germany Institute of Communication Networks and Computer Engineering University of Stuttgart StuttgartD-70569 Germany

ISBN: (纸本)9783800739387

Automatic Repeat reQuest (ARQ) data link layer protocols improve the reliability of communication in Free Space Optical (FSO) fading channels using feedback information. The objective of this paper is to analyse the simulative performance of different ARQ mechanisms for a FSO inter-High Altitude Platform (HAP) scenario. A bi-directional symmetrical inter-HAP channel was modelled considering the combined influence of atmospheric turbulence-induced scintillation and miss-pointing induced fading at the receiver. Then selected ARQ schemes were investigated via event-based simulations in terms of transmission efficiency. © 2020 *** right reserved.

关键词： Data Link Layer

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Ensemble Learning-based Traffic Classification with Small-Scale Datasets for Wireless networks

Ensemble Learning-based Traffic Classification with Small-Sc...

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IEEE Conference on computer communications Workshops, INFOCOM Wksps

作者： Xiaorong Wang Wenting Wei Xiaoshan Yu Danyang Zheng Neeraj Kuma Lei Liu State Key Laboratory of Integrated Service Networks Xidian University Xi'an China School of Computing and Artificial Intelligence Southwest Jiaotong University China Department of Computer Science and Engineering Thapar Institute of Engineering and Technology India Guangzhou Institute of Technology Xidian University Xi'an China Shaanxi Key Laboratory of Information Communication Network and Security Xi'an University of Posts & Telecommunications Xi'an China

ISBN: (数字)9798350384475

ISBN: (纸本)9798350384482

Traffic classification is an essential part of intelligent network management in Fifth generation (5G) networks, from quality of service guarantees to security monitoring. With the evolution of diverse services and applications over 5G networks, traffic patterns and their implications also becoming more complicated, especially in wireless networks. How to dynamically manage the growing traffic demand and satisfy the quality of service (QoS) needs of new applications is particularly critical. The biggest challenge is how to identify traffic types accurately without application information and manual features. However, the existing deep learning (DL)-based classifiers heavily rely on extensive and high-quality samples, which proves impractical to obtain in wireless networks. To overcome this limitation, we propose an ensemble Learning based traffic classification model to provide accurate identification with small-scale datasets, where Attention-based Long Short-Term Memory networks are bagged to train this classifier. The ensemble learning approach employs a combinatorial design involving five base models to construct more accurate and robust learning models. This enables effective feature absorption, making it feasible to train classifiers on limited sample sets. Comprehensive experiments are conducted using a real-world dataset covering 16 applications. Results demonstrate that, even with a mere 10% of training samples, our proposed model achieves a classification accuracy of 95.57% and a precision of 95.83%, surpassing multiple cutting-edge methods.

关键词： Training Accuracy 5G mobile communication Wireless networks Computational modeling Quality of service Telecommunication traffic

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