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International Conference on Computer and Communications (ICCC)

作者： Dianang Li Xinxin He Jie Lv Tao Wang Beijing Laboratory of Advanced Information Networks Beijing University of Posts and Telecommunications Beijing China Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China

The multiple-in-multiple-out (MIMO) radar is deployed to assist the millimeter wave (mmWave) communication with low beam training overhead in vehicle-to-infrastructure (V2I), which has attracted increasing attention. This paper proposes a structured weighted radar aided beam selection. To be specific, since the spatial information provided by radar involves inevitable inaccuracy due to the angle deviation, we calculate the probability distribution of the codewords based on the deviation angle and use it for designing the training codebook. Furthermore, beam selection is formulated as prior weighted sparse signal recovery problem, where the prior structured-weight for communication is determined by the spatial congruence with radar channel, and the difference between two frequency bands is derived to correct the weight. The resulting prior structured weight is further deployed to the orthogonal matching pursuit algorithm to enhance its performance. Simulation results demonstrate that the proposed method provides the efficient and reliable beam selection performance of the mobility mmWave channel with fewer training overhead.

关键词： Training MIMO radar Vehicle-to-infrastructure Simulation Matching pursuit algorithms Millimeter wave radar Radar tracking

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Machine Learning Inspired Binocular Vision Indoor Positioning system Based on QR Code Beacon 2020

Machine Learning Inspired Binocular Vision Indoor Positionin...

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4th International Conference on Innovation in Artificial Intelligence, ICIAI 2020

作者： Deng, Xinyi He, Dazhong Zhou, Wenli Yang, Yang Zhang, Yue Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China

ISBN: (纸本)9781450376587

With the development of the Internet of Things, indoor positioning technology has a wider application prospect. Binocular vision positioning technology can effectively meet the needs of high positioning accuracy and low hardware costs. Based on the traditional binocular vision ranging process, we aims to improve the ranging and positioning accuracy of the binocular system by using machine learning (ML) methods and Quick Response (QR) code beacons. First, this article will use the binarization technology to locate the QR code area. Second, using the fully convolutional network (FCN) structure, we design a convolutional neural network (CNN) model and train it on the KITTI dataset, and convolve the QR code region to get the disparity map of the region. Third, in order to accurately locate the coordinate position of the beacon center, our proposed system uses a density-based clustering algorithm to cluster 3D point clouds, and uses binary linear regression to fit the plane equations of the QR code beacon. Finally, the positioning experiments are carried out in practical applications. The experimental results show that compared with the traditional binocular vision algorithm, the system has higher positioning accuracy, and has performance close to the theoretical accuracy of binocular vision. © 2020 ACM.

关键词： Convolutional neural networks

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On the Impact of Uncertainty and Calibration on Likelihood-Ratio Membership Inference Attacks

arXiv

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arXiv 2024年

作者： Zhu, Meiyi Guo, Caili Feng, Chunyan Simeone, Osvaldo Beijing Key Laboratory of Network System Architecture and Convergence School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing100876 China lab Department of Engineering King’s College London LondonWC2R 2LS United Kingdom

In a membership inference attack (MIA), an attacker exploits the overconfidence exhibited by typical machine learning models to determine whether a specific data point was used to train a target model. In this paper, we analyze the performance of the likelihood ratio attack (LiRA) within an information-theoretical framework that allows the investigation of the impact of the aleatoric uncertainty in the true data generation process, of the epistemic uncertainty caused by a limited training data set, and of the calibration level of the target model. We compare three different settings, in which the attacker receives decreasingly informative feedback from the target model: confidence vector (CV) disclosure, in which the output probability vector is released;true label confidence (TLC) disclosure, in which only the probability assigned to the true label is made available by the model;and decision set (DS) disclosure, in which an adaptive prediction set is produced as in conformal prediction. We derive bounds on the advantage of an MIA adversary with the aim of offering insights into the impact of uncertainty and calibration on the effectiveness of MIAs. Simulation results demonstrate that the derived analytical bounds predict well the effectiveness of MIAs. Copyright © 2024, The Authors. All rights reserved.

关键词： Prediction models

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A Low Profile Wideband Absorption Structure based on Metasurface Embed with Lumped Resistance 3

A Low Profile Wideband Absorption Structure based on Metasur...

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3rd IEEE International Conference on Electronic Information and Communication Technology, ICEICT 2020

作者： Jin, Yaping Hong, Weijun Cai, Jiaqi Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China

ISBN: (纸本)9781728190457

Metamaterials exhibit more and more novel electromagnetic properties. Common ones are zero refractive index materials and negative refractive index materials. Therefore, metamaterials are widely used in antennas and antenna arrays designed today. In this paper, a metasurface embedded with lumped resistance is designed for broad band microwave absorption. The proposed metasurface is a periodic structure whose unit is consisted of four patches who are separated by a cross patch at center and surrounded by L shape patches at corner. The dimension of the proposed absorption structure is 16.5mm. The simulations show that the proposed absorption structure has a wide absorption band of 5.7-12.3 GHz with 90% absorptivity. Due to the symmetry, the proposed metasurface show great tolerance on oblique incident angle, simulations show that it can keep a wide band absorption above 90% with oblique incident angle to 60°. © 2020 IEEE.

关键词： Metamaterials

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A dual circularly polarized flower-shaped antenna for WiFi-6E basestation communications with low sidelobe level and high gain

Results in Engineering

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Results in Engineering 2025年 26卷

作者： Ding, Xiao Zhou, Zhengdong Feng, Botao Wu, Sulin Sim, Chow-Yen-Desmond Deng, Li Faculty of Humanities and Arts Macau University of Science and Technology Macau 999078 China College of Electronics and Information Engineering Shenzhen University Shenzhen518060 China Shenzhen518060 China Department of Electrical Engineering Feng Chia University Taichung40724 Taiwan Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing100876 China

This paper proposes a dual circularly polarized (CP) flower-shaped antenna with low sidelobe levels and high gain for WiFi-6E basestation communications. The antenna consists of two printed circuit board (PCB) substrates and a polyvinyl chloride (PVC) radome, and is excited by a pair of coaxial cables. Initially, a flower-shaped parasitic patch etched with slots is placed atop a square main radiated patch that is directly fed by two orthogonal "L"-shaped microstrip lines with constant amplitude in phase, achieving wideband, high gain, and dual CP characteristics. Furthermore, a three-level T-junction power divider network collaborates in conjunction with a dual-port electrical bridge to excite an array that is comprised of the proposed 4×4 antenna elements to achieve higher array gain. Finally, an open box-shaped PVC radome is selected for fixation and protection, contributing significantly to sidelobe level (SLL) reduction. The working mechanisms including precise phase control and SLL reduction, etc., are analyzed using equivalent circuit and E-field distribution, among other methods. Measured results demonstrate excellent performances, such as a low profile of 0.074λ0 (λ0 is the free-space wavelength at the starting frequency), a low SLL of less than -14.4 dB, a wide impedance bandwidth of 20% (5.85-7.15 GHz), a wide axial ratio (AR) bandwidth of 21% (5.83-7.4 GHz), a peak gain of larger than 19.4 dBic in left hand circular polarization (LHCP), another peak gain of better than 19.6 dBic in right hand circular polarization (RHCP), and a high radiation efficiency of larger than 72%. © 2025 The Author(s)

关键词： Wi-Fi

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Communication network Selection for Distribution network Based on Analytic Hierarchy Process

Communication Network Selection for Distribution Network Bas...

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Power Engineering Application (ICPEA), IEEE International Conference in

作者： Wei Ge Qi Wei Weijun Hong Yuchen Wu Cui Li Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China State Grid Economic and Technological Research Institute CO. LTD Beijing China Beijing Laboratory of Advanced Information Network Beijing University of Posts and Telecommunications Beijing China State Grid Fujian Economic Research Institute Fuzhou China

The access of large-scale distributed new energy has high requirements for the protection of new distribution network and communication network, but the selection of the communication network has no definite standard. In this paper, a communication network selection mechanism based on Analytic Hierarchy Process (AHP) is proposed to solve the problem of smart grid communication network selection. This method is based on the principle of decision-making analysis combining qualitative and quantitative analysis of multi- objective complex problems. The weight of indexes at all levels are calculated by the judgment matrix. After the consistency test, the overall judgment matrix is calculated to select the best scheme, which achieves the effect of decomposing and analyzing the communication network of distribution network. Through the analysis of 5 kinds of communication networks, namely optical fiber communication network, 4G network, 5G network, wireless private network and power line carrier, this research constructs the AHP model with accessibility, coverage, economy, reliability and security as the main parameter indexes, and obtains that 5G is the optimal scheme with 26.0178% of the comprehensive weight. Therefore, 5G network is more suitable for the application in the distribution network under the current new energy access.

关键词： Wireless communication 5G mobile communication Distribution networks Optical fiber communication Smart grids Communication networks Security

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Machine Learning Based Joint Offloading and Trajectory Design in UAV Based MEC system for IoT Devices 6

Machine Learning Based Joint Offloading and Trajectory Desig...

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6th IEEE International Conference on Computer and Communications, ICCC 2020

作者： Ma, Xingjie Yin, Changchuan Liu, Xuanlin Beijing Key Laboratory of Network System Architecture and Convergence Beijing Laboratory of Advanced Information Network Beijing University of Posts and Telecommunications Beijing China

ISBN: (纸本)9781728186351

In this paper, we consider an unmanned aerial vehicle (UAV)-based mobile edge computing (MEC) system for Internet of Things devices (IoTDs), in which the mobile UAV equipped with computing resources provides service for all IoTDs in the system and each IoTD also has a certain amount of computing power. Each IoTD has a computing task to be completed and the computing task will be offloaded to the UAV or implemented locally. After the UAV completes the service for any IoTD, it proceeds to the next IoTD, until that all IoTDs in the system have been served. The UAV can collect all information related to all IoTDs before taking off, such as the data size of the computing task and the coordinate of the locations of all IoTDs. Our goal is to minimize the total delay of the system (i.e., flying delay, transmission delay, local computing delay and UAV-aided edge computing delay) through joint optimization of the flying trajectory of the UAV and the ratio of the offloading tasks. Aiming at this problem, a machine learning framework based on Q-learning algorithm is proposed so as to minimize the total delay of the system. Simulation results show that the proposed algorithm can achieve up to 15.7% and 38.0% gain compared to the random algorithm with dynamic selection of task offloading mode and the Q-learning algorithm with fixed selection of task offloading mode. © 2020 IEEE.

关键词： Internet of things

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A lightweight fully convolutional network for cardiac MRI segmentation

A lightweight fully convolutional network for cardiac MRI se...

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2020 International Conference on Computer Information and Big Data Applications, CIBDA 2020

作者： Yang, Wenjie Li, Shufang Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijng China

ISBN: (纸本)9781728198378

Cardiac magnetic resonance imaging is a commonly used method to assess the function and structure of the cardiovascular system. Separating the heart structure from Cardiac MRI is an important step in calculating the cardiac function index. The automatic segmentation algorithm can significantly reduce the workload of the doctor. Most of the current automatic segmentation algorithm has a large calculation amount and size, has high requirements on the hardware. Based on the U-Net model, this paper proposes a lightweight full convolution model with separable convolution and residual connection. Experiments show that the model reduces the number of parameters while ensuring learning ability and balances speed and accuracy. © 2020 IEEE.

关键词： Convolution

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Sum-Rate Maximization for Active RIS-Aided Downlink RSMA system

Sum-Rate Maximization for Active RIS-Aided Downlink RSMA Sys...

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IEEE Conference on Computer Communications Workshops, INFOCOM Wksps

作者： Xinhao Li Tao Wang Haonan Tong Zhaohui Yang Yijie Mao Changchuan Yin Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China College of Information Science and Electronic Engineering Zhejiang University Hangzhou China School of Information Science and Technology ShanghaiTech University Shanghai China

In this paper, the problem of sum-rate maximization for an active reconfigurable intelligent surface (RIS) assisted downlink rate-splitting multiple access (RSMA) transmission system is studied. In the considered model, the active RIS is deployed to overcome severe power attenuation, which is caused by the cumulative product of RIS incidence path loss and the reflection path loss. Since the active RIS can adjust both the phase and the amplitude of the incident signal simultaneously, the RIS control scheme requires delicate design to improve RSMA communication performance. To address this issue, a sum-rate maximization problem is formulated to jointly optimize the beamforming vectors, rate allocation vector, and RIS precoding matrix. To solve this non-convex sum-rate maximization problem, an iterative algorithm based on fractional programming (FP) and quadratic constraint quadratic programming (QCQP) is proposed. In particular, the proposed algorithm firstly decomposes the original problem into two subproblems, namely, 1) beamforming and rate allocation optimization and 2) active RIS precoding optimization. The corresponding variables of the two subproblems are optimized through sequential convex approximation (SCA) and block coordinate descent (BCD), respectively. Numerical results show that the proposed active RIS-aided RSMA system could increase the sum-rate by up to 45% over the conventional passive RIS-aided RSMA system with the same energy consumption.

关键词：

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Sum-Rate Maximization for Active RIS-Aided Downlink RSMA system

arXiv

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arXiv 2023年

作者： Li, Xinhao Wang, Tao Tong, Haonan Yang, Zhaohui Mao, Yijie Yin, Changchuan Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China College of Information Science and Electronic Engineering Zhejiang University Hangzhou China School of Information Science and Technology ShanghaiTech University Shanghai China

n this paper, the problem of sum-rate maximization for an active reconfigurable intelligent surface (RIS) assisted downlink rate-splitting multiple access (RSMA) transmission system is studied. In the considered model, the active RIS is deployed to overcome severe power attenuation, which is caused by the cumulative product of RIS incidence path loss and the reflection path loss. Since the active RIS can adjust both the phase and the amplitude of the incident signal simultaneously, the RIS control scheme requires delicate design to improve RSMA communication performance. To address this issue, a sum-rate maximization problem is formulated to jointly optimize the beamforming vectors, rate allocation vector, and RIS precoding matrix. To solve this non-convex sum-rate maximization problem, an iterative algorithm based on fractional programming (FP) and quadratic constraint quadratic programming (QCQP) is proposed. In particular, the proposed algorithm firstly decomposes the original problem into two subproblems, namely, 1) beamforming and rate allocation optimization and 2) active RIS precoding optimization. The corresponding variables of the two subproblems are optimized through sequential convex approximation (SCA) and block coordinate descent (BCD), respectively. Numerical results show that the proposed active RIS-aided RSMA system could increase the sum-rate by up to 45% over the conventional passive RIS-aided RSMA system with the same energy consumption. Copyright © 2023, The Authors. All rights reserved.

关键词： Beamforming

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