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Multi Topological Charges Vortex Beam Generator Based on Nonlinear Bound States in the Continuum with Improvement of Nonlinear Conversion Efficiency

SSRN

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SSRN 2023年

作者： Xu, Hang Li, Hui Tan, Qi Song, Chunyu Li, Mengyao Liu, Yanyan Zhang, Yating Wang, Bo Li, Jie Yao, Jianquan Ministry of Education School of Precision Instruments and Opto-Electronics Engineering Tianjin University Tianjin300072 China Function laboratory for Marine Fisheries Science and FoocProduction Processes Qingdao National LaboratoryTechnology Qingdao China Key Laboratory of Quantum Matt Science Henan Key Laboratory of Photovoltaic Materials Henan University KaifengHenan475004 China Information Materials and Device Applications Key Laboratory of Sichuan ProvincialUniversities Chengdu University of Information Technology 610225 China Science and Technology on Electro-Optical Information Security Control Laboratory Tianjin300308 China

In the momentum space of bound states in the continuum (BIC), vortex configurations around the Γ-point are generated by the selection rules. The electric field distribution close to the BIC satisfies twofold rotational symmetry (C2). Since the periodic structure of 2D photonic crystals (PhCs) supports the generation of odd harmonics, this characteristic provides an attractive approach for generating high-harmonic optical vortex (OV) beams with both left and right handedness. Also, the topological charge of OV beams generated by C4v-symmetric PhCs can be further improved by an increase of structural symmetry. Moreover, since the nonlinear conversion efficiency of directly used PhCs is low, their practicability is limited. Here, a hexagonal arrangement of C6v-symmetric 2D PhCs slab is selected. Through energy band selection, higher order fundamental and nonlinear OV beams can be generated, which can not only cover the topological charge of the C4v-symmetric structure, but also generate more abundant topological charge. In addition, we improve the third-order nonlinear conversion efficiency by the mirror approach, which is 22 times greater than with the direct use of PhCs. This method can improve the channel capacity of OV generators based on BICs and make them more practical. © 2023, The Authors. All rights reserved.

关键词： Conversion efficiency

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Two Enhanced-Rate Power Allocation Strategies for Active IRS-Assisted Wireless Network

Two Enhanced-Rate Power Allocation Strategies for Active IRS...

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Computer communication and Artificial Intelligence (CCAI), International Conference on

作者： Qiankun Cheng Rongen Dong Wenlong Cai Ruiqi Liu Feng Shu Jiangzhou Wang Hainan University School of Information and Communication Engineering Haikou China National Key Laboratory of Science and Technology on Aerospace Intelligence Control Beijing Aerospace Automatic Control Institute Beijing China Wireless and Computing Research Institute ZTE Corporation Beijing China University of Kent School of Engineering Canterbury U.K.

ISBN: (数字)9798350362763

ISBN: (纸本)9798350362770

Due to its ability of overcoming the impact of double-fading effect, active intelligent reflecting surface (IRS) has attracted a lot of attention. Unlike passive IRS, active IRS should be supplied by power, thus adjusting power between base station (BS) and IRS having a direct impact on the system rate performance. In this paper, the active IRS-aided network under a total power constraint is modeled with an ability of adjusting power between BS and IRS. Given the transmit beamforming at BS and reflecting beamforming at IRS, the SNR expression is derived to be a function of power allocation (PA) factor, and the optimization of maximizing the SNR is given. Subsequently, two high-performance PA strategies, enhanced multiple random initialization Newton's (EMRIN) and Taylor polynomial approximation (TPA), are proposed. The former is to improve the rate performance of classic Newton's method to avoid involving a local optimal point by using multiple random initializations. To reduce its high computational complexity, the latter provides a closed-form solution by making use of the first-order Taylor polynomial approximation to the original SNR function. Actually, using TPA, the original optimization problem is transformed into a problem of finding a root for a third-order polynomial. Simulation results are as follows: the first-order TPA of SNR fit its exact expression well, the proposed two PA methods performs much better than fixed PA in accordance with rate, and approaches exhaustive search as the number of IRS reflecting elements goes to large-scale.

关键词： Array signal processing Wireless networks Simulation Polynomials Vectors Resource management Newton method

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A Novel Edge Computing Based Area Navigation Scheme

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Computers, Materials & Continua 2020年第12期65卷 2385-2396页

作者： Jianzhong Qi Qingping Song Jim Feng School of Information Science and Technology North China University of TechnologyBeijing100144China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China Science and Technology on Information Systems Engineering Laboratory Beijing Institute of Control and Electronic TechnologyBeijing100038China Amphenol Global Interconnect Systems San JoseCA 95131USA

The area navigation system,discussed in this paper,is composed of ground responders and a navigation terminal and can position a high-velocity aircraft and measure its *** navigation system is silent at ordinary *** sends out a request signal when positioning is required for an aircraft,and then the ground responders send a signal for resolving the *** the direct sequence spread spectrum and frequency hopping,the concealed communication mode is used in the whole communication process,with short communication pulses as much as possible,so the system has strong concealment and anti-interference *** the transmission delay is apparent in the response communication mode,there is a big error where the common navigation algorithm is used for the positioning and velocity measurement of a high-velocity *** this paper,a new algorithm is proposed,which can eliminate the influence of response communication delay on the positioning of a high-velocity moving target to realize the precise positioning and velocity measurement of a high-velocity aircraft.

关键词： Navigation pseudo-noise code ranging positioning velocity measurement edge computing

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Joint Beamforming Design for Integrated Sensing and communication Systems with Hybrid-Colluding Eavesdroppers

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IEEE Transactions on communications 2025年

作者： Liu, Meiding Zhou, Zhengchun Shi, Qiao Li, Guyue Liu, Zilong Fan, Pingzhi Lee, Inkyu Southwest Jiaotong University School of Information Science and Technology Chengdu611756 China Key Laboratory of Analytical Mathematics and Applications China Southeast University School of Cyber Science and Engineering Nanjing210096 China Purple Mountain Laboratories for Network and Communication Security Nanjing210096 China University of Essex School of Computer Science and Electronics Engineering ColchesterCO4 3SQ United Kingdom Southwest Jiaotong University Key Laboratory of Information Coding and Transmission Chengdu611756 China Korea University School of Electrical Engineering Seoul02841 Korea Republic of

In this paper, we consider the physical layer security (PLS) problem for integrated sensing and communication (ISAC) systems in the presence of hybrid-colluding eavesdroppers, where an active eavesdropper (AE) and a passive eavesdropper (PE) collude to intercept the confidential information. To ensure the accuracy of sensing while preventing the eavesdropping, a base station transmits a signal consisting of information symbols and sensing waveform, in which the sensing waveform can be also used as artificial noise to interfere with eavesdroppers. Under this setup, we propose an alternating optimization-based two stage scheme (AO-TSS) for improving the sensing and communication performance. In the first stage, based on the assumptions that the perfect channel state information (CSI) of the AE and statistical CSI of the PE are known, the communication and sensing beamforming problem is formulated with the objective of minimizing the weighted sum of the beampattern matching mean squared error (MSE) and cross-correlation, subject to the secure transmission constraint. To tackle the non-convexity, we propose a semi-definite relaxation (SDR) algorithm and a reduced-complexity zero-forcing (ZF) algorithm. Then, the scenarios are further extended to more general cases with imperfect AE CSI and unknown PE CSI. To further improve the communication performance, the second-stage problem is developed to optimize the secrecy rate threshold under the radar performance constraint. Finally, numerical results demonstrate the superiority of the proposed scheme in terms of sensing and secure communication. © 1972-2012 IEEE.

关键词： Mean square error

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Prediction of piRNA-mRNA interactions based on an interactive inference network

Prediction of piRNA-mRNA interactions based on an interactiv...

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IEEE International Conference on Bioinformatics and Biomedicine (BIBM)

作者： Yajun Liu Ru Li Aimin Li Rong Fei Xie Guo Fang-Xiang Wu Shaanxi Key Laboratory for Network Computing and Security Technology Xi'an University of Technology Xi'an China Shaanxi Key Laboratory of Complex System Control and Intelligent Information Processing Xi'an University of Technology Xi'an China Department of Computer Science Department of Mechanical Engineering Division of Biomedical Engineering University of Saskatchewan Saskatoon Canada

As the largest class of small non-coding RNAs, piRNAs primarily present in the reproductive cells of mammals, which influence post-transcriptional processes of mRNAs in multiple ways. Effective methods for predicting piRNA and mRNA target relationships can help identify piRNA functions, investigate the possibility of piRNAs as biomarkers and therapeutic targets. In this study, we propose a computational approach for classifying the relationships of piRNA-mRNA pairs based on an interactive inference network (IIN). First, we gather piRNA-mRNA target data, collect sequence data by position alignment, and construct a benchmark dataset. Furthermore, a reliable negative set is constructed by positive-unlabeled learning. Finally, we view a piRNA and a mRNA sequence as a premise and hypothesis sentence, respectively, and IIN model is used to predict the relationship between them. The experiments demonstrate that our method effectively characterizes piRNA-mRNA interaction and could be beneficial for researchers to investigate piRNA functions.

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Two Rapid Power Iterative DOA Estimators for UAV Emitter Using Massive/Ultra-massive Receive Array

arXiv

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arXiv 2022年

作者： Chen, Yiwen Shu, Feng Jie, Qijuan Zhan, Xichao Wang, Xuehui Sun, Zhongwen Yan, Shihao Cai, Wenlong Zhang, Peng Chen, Peng The School of Information and Communication Engineering Hainan Unversity Haikou570228 China The School of Science and Security Research Institute Edith Cowan University PerthWA6027 Australia The National Key Laboratory of Science and Technology on Aerospace Intelligence Control Beijing Aerospace Automatic Control Institute Beijing100854 China

To provide rapid direction finding (DF) for unmanned aerial vehicle (UAV) emitter in future wireless networks, a low-complexity direction of arrival (DOA) estimation architecture for massive multiple input multiple output (MIMO) receiver arrays is constructed. In this paper, we propose two strategies to address the extremely high complexity caused by eigenvalue decomposition of the received signal covariance matrix. Firstly, a rapid power-iterative rotational invariance (RPI-RI) method is proposed, which adopts the signal subspace generated by power iteration to gets the final direction estimation through rotational invariance between subarrays. RPI-RI makes a significant complexity reduction at the cost of a substantial performance loss. In order to further reduce the complexity and provide a good directional measurement result, a rapid power-iterative Polynomial rooting (RPI-PR) method is proposed, which utilizes the noise subspace combined with polynomial solution method to get the optimal direction estimation. In addition, the influence of initial vector selection on convergence in the power iteration is analyzed, especially when the initial vector is orthogonal to the incident wave. Simulation results show that the two proposed methods outperform the conventional DOA estimation methods in terms of computational complexity. In particular, the RPI-PR method achieves more than two orders of magnitude lower complexity than conventional methods and achieves performance close to CRLB. Moreover, it is verified that the initial vector and the relative error have a significant impact on the performance of the computational complexity. Copyright © 2022, The Authors. All rights reserved.

关键词： Covariance matrix

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Corrigendum to ‘regulation of corn starch on the properties of tremella polysaccharide-egg white protein-orange juice composite gel and its application in 3D printing’ [food chemistry: X 27 (2025) 102382] (Food Chemistry: X (2025) 27, (S2590157525002299), (10.1016/***.2025.102382))

引用

Food Chemistry: X 2025年 27卷 102449页

作者： Liu, Lili Shao, Beibei Yang, Wanlin Cheng, Weiwei Ding, Yue Xiao, Feng College of Food and Bioengineering National Experimental Teaching Demonstration Center for Food Processing and Security Henan Engineering Technology Research Center of Food Raw Materials International Joint Laboratory of Food Processing and Quality Safety Control of Henan Province Henan Engineering Technology Research Center of Food Microbiology Henan University of Science and Technology Luoyang471023 China School of instrument Science and Opto-Electronics Engineering Beijing Information Science and Technology University Beijing100192 China

关键词：

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Cross-heterogeneous Domain Authentication Scheme Based on Blockchain

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Journal of Artificial Intelligence and technology 2021年第2期1卷 92-100页

作者： Jing Liu Yixin Liu Yingxu Lai Rongchen Li Siyu Wu Sami Mian College of Computer Science Faculty of Information TechnologyBeijing University of TechnologyBeijing 100124China Shaanxi Key Laboratory of Network and System Security Xi’an 710071China Science and Technology on Information Assurance Laboratory Beijing 100072China Engineering Research Center of Intelligent Perception and Autonomous Control Ministry of EducationBeijing 100124China Fan Gongxiu Honors College Beijing University of TechnologyBeijing 100124China University of Pittsburgh PittsburghPA 15260USA

With the rising popularity of the Internet and the development of big data technology,an increasing number of organizations are opting to cooperate across domains to maximize their *** organizations use public key infrastructure to ensure security in accessing their data and ***,with the continuous development of identity-based encryption(IBE)technology,small-and medium-sized enterprises are increasingly using IBE to deploy internal authentication *** solve the problems that arise when crossing heterogeneous authentication domains and to guarantee the security of the certification process,we propose using blockchain technology to establish a reliable cross-domain authentication *** the distributed and tamper-resistant characteristics of the blockchain,we design a cross-domain authentication model based on blockchain to guarantee the security of the heterogeneous authentication process and present a cross-domain authentication protocol based on *** model does not change the internal trust structure of each authentication domain and is highly ***,on the premise of ensuring security,the process of verifying the signature of the root certificate in the traditional cross-domain authentication protocol is improved to verify the hash value of the root certificate,thereby improving the authentication *** developed prototype exhibits generality and simplicity compared to previous methods.

关键词： public key infrastructure identity-based encryption cross-domain authentication blockchain

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Cross-Layer security for Semantic communications: Metrics and Optimization

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IEEE Transactions on Vehicular technology 2025年

作者： Wang, Lingyi Wu, Wei Zhou, Fuhui Qin, Zhijin Wu, Qihui Nanjing University of Posts and Telecommunications College of Science Nanjing210003 China Nanjing University of Posts and Telecommunications College of Communication and Information Engineering Nanjing210003 China Southeast University National Mobile Communications Research Laboratory Nanjing210096 China Anhui Province Key Laboratory of Cyberspace Security Situation Awareness and Evaluation China Nanjing University of Aeronautics and Astronautics College of Electronic and Information Engineering Nanjing210000 China Tsinghua University Department of Electronic Engineering Beijing100084 China Beijing National Research Center for Information Science and Technology Beijing China State Key Laboratory of Space Network and Communications Beijing China

Different from traditional secure communication that focuses on symbolic protection at the physical layer, semantic secure communication requires further attention to semantic-level task performance at the application layer. There is a research gap on how to comprehensively evaluate and optimize the security performance of semantic communication. In order to fill this gap, a unified semantic security metric, the cross-layer semantic secure rate (CLSSR), is defined to estimate cross-layer security requirements at both the physical layer and the application layer. Then, we formulate the maximization problem of the CLSSR with the mixed integer nonlinear programming (MINLP). We propose a hierarchical AI-native semantic secure communication network with a reinforcement learning (RL)-based semantic resource allocation scheme, aiming to ensure the cross-layer semantic security (CL-SS). Finally, we prove the convergence of our proposed intelligent resource allocation, and the simulation results demonstrate that our proposed CLSS method outperforms the traditional physical layer semantic security (PL-SS) method in terms of both task reliability and CLSSR. © 1967-2012 IEEE.

关键词： Reinforcement learning

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Identifying IoT Devices Based on Spatial and Temporal Features from Network Traffic

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security and communication Networks 2021年第1期2021卷

作者： Yin, Feihong Yang, Li Ma, Jianfeng Zhou, Yasheng Wang, Yuchen Dai, Jiahao School of Computer Science and Technology Xidian University Xi'an710071 China School of Cyber Engineering Xidian University Xi'an710071 China Science and Technology on Communication Information Security Control Laboratory Jiaxing314000 China

With the rapid growth of the Internet of Things (IoT) devices, security risks have also arisen. The preidentification of IoT devices connected to the network can help administrators to set corresponding security policies according to the functionality and heterogeneity of the devices. However, the existing methods are based on manually extracted features and prior knowledge to identify the IoT devices, which increases the difficulty of the device identification task and reduces the timeliness. In this paper, we present CBBI, a novel IoT device identification approach. On the one hand, CBBI uses a hybrid neural network model Conv-BiLSTM to automatically learn the representative spatial and temporal features from the network traffic, such as the position relationship of the internal organization structure in network communication traffic, the time sequence of the data packets, and the duration of the network flow. On the other hand, CBBI contains the data augmentation module FGAN that solves the problem of data imbalance in deep learning and improves the accuracy of the model. Finally, we used the public dataset and laboratory dataset to evaluate CBBI from multiple dimensions. The evaluation results for different datasets show that our approach achieves the accurate identification of IoT devices. © 2021 Feihong Yin et al.

关键词： Internet of things

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