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15th International Conference on communication Software and networks, ICCSN 2023

作者： Su, Yi Wei, Wei Liu, Lizhe Wang, Bin Sun, Chenhua Fu, Shu Wang, Dongdong College of Microelectronics and Communication Engineering Chongqing University Chongqing China Academy for Network & Communications of Cetc Science and Technology on Communication Networks Laboratory Shijiazhuang China

ISBN: (纸本)9798350329360

With the advent of 5G, wireless communication has greatly changed people's lifestyles. However, limited by the coverage of terrestrial cellular networks, the demand for communication services of mobile phones in remote areas is difficult to be met. In order to meet the large coverage and quality of service (QoS) requirements of mobile phones, we consider a non-orthogonal multiple access (NOMA)-based mobile phones and internet of things (IoT) fusion satellite network. In this network, low earth orbit (LEO) satellite can significantly enlarge the coverage while NOMA and IoT further improve the utilization efficiency of resources. Aiming at maximizing the QoS satisfaction rate of mobile phones and the sum rate of internet of things devices, we formulate a joint optimization problem considering NOMA user grouping, inter-group power allocation and intra-group power allocation. To tackle the problem, we design a QoS priority joint optimization algorithm based on proximal policy optimization (Q-PPO). The experimental results show that the proposed Q-PPO algorithm always has considerable performance in QoS satisfaction rate and sum rate of internet of things devices. © 2023 IEEE.

关键词： Quality of service

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Manipulation of Orbital Angular Momentum Energy by Huygens' Metasurfaces with Donut-shaped Phase Distribution

Manipulation of Orbital Angular Momentum Energy by Huygens' ...

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2024 Photonics and Electromagnetics Research Symposium, PIERS 2024

作者： Cui, Sihan Huang, Xiaojun Xi'an University of Science and Technology College of Communication and Information Engineering Xi'an710054 China Key Laboratory of Network Convergence Communication Xi'an710054 China

ISBN: (纸本)9798350375909

In wireless communication systems, a multibeam orbital angular momentum (OAM) can be used to increase the number of spatial channels by space-division multiplexing. Furthermore, the multimode OAM is used to enhance the channel capacity by mode-division multiplexing. However, among the previously reported methods, few of them can flexibly and reliably manipulate the energy of OAM in both space-division multiplexing and mode-division multiplexing. In this work, inspired by the theory related to uniform circular antenna arrays, we propose a simple and universal method to manipulate the radiation power and radiation direction of a LP OAM. Firstly, a highly integrated Huygens' element is designed to achieve high transmission and 360° phase control by modulating mutually interfering electric and magnetic dipole resonances. On this basis, linking the donut-shaped phase distribution of the metasurface and the generated vortex beams was accomplished to manipulate the energy proportion in different modes of the multimode OAM and the energy proportion of energy manipulation between different beams of the multibeam OAM. The proposed power manipulation scheme provides a new way to realize controllable LP OAM, which has potential applications in OAM-based multiplexed communications. © 2024 IEEE.

关键词： Antenna arrays

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Design of Multi-Scenario Robust MCS Switching Strategy Based on RDQN for 5G LEO Satellite Adaptive Transmission System 15

Design of Multi-Scenario Robust MCS Switching Strategy Based...

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15th International Conference on communication Software and networks, ICCSN 2023

作者： Wang, Xiujie Wang, Dongdong Liu, Lizhe Wang, Bin Zhang, Weijia Sun, Chenhua Academy for Network and Communications of Cetc Science and Technology on Communication Networks Laboratory Shijiazhuang050081 China Academy for Network and Communications of Cetc Shijiazhuang050081 China

ISBN: (纸本)9798350329360

In this paper, we focus on the design of a multi-scenario robust MCS switching strategy for 5G LEO satellite adaptive transmission system. Firstly, we analyze and model the large- and small-scaling fading of the LEO satellite channel based on 3GPP 38.811 to obtain all the SNR points for the given scenario. Secondly, we carefully designed the direct input and feedback input of the convolutional neural network (CNN), which facilitates to explore higher-dimensional search space and learn the scenario-related features. Simulation results demonstrate that the proposed method shows excellent performance in both single-scenario and multi-scenario conditions. Compared with the fixed threshold switching strategy (combined with high precision SNR estimation) whose performance is very close to the theoretical upper bound, the average throughput can still be promoted by 3.4% and the average outage probability can be reduced from 4.8% to 1.4%. Moreover, the designed switching strategy effectively incorporate the combination of multiple scenarios schemes in the adaptive transmission process without channel sensing technology, which greatly improves the robustness of the system. © 2023 IEEE.

关键词： Reinforcement learning

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BEM Based Fast Time-varying Channel Estimation Method for 5G Integrated Satellite Systems 22

BEM Based Fast Time-varying Channel Estimation Method for 5G...

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22nd IEEE International Conference on communication technology, ICCT 2022

作者： Yang, Shunyao Wang, Dongdong Liu, Lizhe Wang, Bin Sun, Chenhua Academy for Network & Communications of Cetc Shijiazhuang050081 China Science and Technology on Communication Networks Laboratory Shijiazhuang050081 China

ISBN: (纸本)9781665470674

This paper proposes a channel estimation method based on discrete prolate spheroidal base extension model (DPS-BEM) for 5G integrated low earth orbit (LEO) satellite systems, which takes the cascade structure of least square (LS) estimator and Kalman filter as the core. Firstly, DPS-BEM is utilized to accurately fit the time-domain channel state matrix. The preliminary estimation coefficients of the basis function could be acquired by a simple and easy implemented LS estimator. Subsequently, the Kalman filtering is cascaded to attenuate the influence of noise, so that the error of the LS estimator can be substantially diminished. Simulation results show that the proposed method has higher precision and robustness compared with the existing common methods. © 2022 IEEE.

关键词： Kalman filters

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5G Integrated Radio Transmission Scheme for Low Earth Orbit Satellite Access network 22

5G Integrated Radio Transmission Scheme for Low Earth Orbit ...

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22nd IEEE International Conference on communication technology, ICCT 2022

作者： Wang, Dongdong Sun, Chenhua Liu, Lizhe Yang, Shunyao Zhang, Zijian Li, Jianwei Zheng, Zuxiang Wang, Xiujie Academy for Network & Communications of Cetc Shijiazhuang050081 China Science and Technology on Communication Networks Laboratory Shijiazhuang050081 China

ISBN: (纸本)9781665470674

This paper comprehensively analyzes the channel transmission characteristics of the low earth orbit satellite. On this basis, the problems when each physical layer process of terrestrial 5G new radio is directly applied to the LEO satellite access network is further analyzed, then the feasible implementation schemes for each 5G integrated physical layer process of the LEO satellite access network are carefully designed. Furthermore, the core technologies of each key step of each 5G integrated physical layer process are briefly discussed. © 2022 IEEE.

关键词： Orbits

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Design of Reflective Metasurface and Signal Enhancement in a Mine Tunnel

Design of Reflective Metasurface and Signal Enhancement in a...

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2024 Photonics and Electromagnetics Research Symposium, PIERS 2024

作者： Wang, Yifei Huang, Xiaojun Xi'an University of Science and Technology College of Communication and Information Engineering Xi'an710054 China Key Laboratory of Network Convergence Communication Xi'an710054 China

ISBN: (纸本)9798350375909

Metasurface (MS) is a technology used in wireless communication systems where the beam steering function of reflective metasurface can be used to improve the transmission and coverage of wireless signals. The electromagnetic environment of the mine tunnel is suitable for placing the reflective metasurface and the communication band is lower than 6GHz. Therefore, it is a great challenge to design the low-frequency reflective metasurface and serve the communication service in the mine. In this paper, a 900MHz reflective metasurface is designed to enhance the signal strength of mine tunnel signals, especially in non-line-of-sight (NLoS)areas. The proposed metasurface unit has a two-layer structure that achieves 3bit coverage of the electromagnetic wave phase with a relatively small size, Only 0.12 times the wavelength. Subsequently, a curved tunnel was established to simulate the propagation of electromagnetic waves underground in the tunnel, and the placement of the metasurface in the mine tunnel eliminated the signal blindness within a certain range and enhanced the signal quality of the NLoS path. © 2024 IEEE.

关键词： Electromagnetic wave propagation

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Satellite Ephemeris Broadcasting Architecture for 5G Integrated LEO Satellite Internet 22

Satellite Ephemeris Broadcasting Architecture for 5G Integra...

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22nd IEEE International Conference on communication technology, ICCT 2022

作者： Li, Jianwei Wang, Dongdong Liu, Lizhe Wang, Bin Sun, Chenhua Academy for Network & Communications of Cetc Shijiazhuang050081 China Science and Technology on Communication Networks Laboratory Shijiazhuang050081 China

ISBN: (纸本)9781665470674

This paper proposes a satellite ephemeris broadcasting architecture for 5G integrated low earth orbit (LEO) Satellite Internet based on two-line element (TLE) ephemeris. By periodically broadcasting the TLE ephemeris, which can be used to assist the user equipment (UE) for satellite selection, Doppler frequency offset and time advance (TA) pre-compensation, etc., the design of the 5G integrated LEO satellite air interface could be greatly simplified. The proposed architecture mainly comprises three stages, the generation, distribution and application of TLE ephemeris. (1) The accurate TLE ephemeris is generated by the simplified general perturbations-4 (SGP4) orbital model, whose input is obtained by the data combination of the orbital data acquired from the spaceborne global navigation satellite system (GNSS) and the satellite tracking station, respectively. (2) The generated ephemeris is sent to the internet, and then be uploaded to its corresponding LEO satellite by the feeder link. The UEs can either obtain the ephemeris from the satellite or from the terrestrial base station. (3) The UE equipped with GNSS system utilizes the TLE ephemeris to calculate the orbital information, Doppler frequency offset and timing advance, etc., so as to realize the efficient and reliable communication with the LEO satellites. The simulation results show that the proposed ephemeris broadcasting architecture can provide reliable and necessary priori information used for the entire physical layer communication process of 5G integrated LEO Satellite Internet over a period of time. © 2022 IEEE.

关键词： Architecture

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Improving AoI by Caching Placement Optimization for a Satellite-Assisted Disaster Area 15

Improving AoI by Caching Placement Optimization for a Satell...

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15th IEEE International Conference on Advanced Infocomm technology, ICAIT 2023

作者： Wang, Yun Wei, Wei Liu, Lizhe Wang, Bin Sun, Chenhua Fu, Shu Wang, Dongdong College of Microelectronics and Communication Engineering Chongqing University Chongqing China Academy for Network & Communications of Cetc Science and Technology on Communication Networks Laboratory Shijiazhuang China

ISBN: (纸本)9798350314120

In this paper, we focus on the age of information (AoI) aware intelligent architecture of emergency service by caching placement optimization on satellite. Such an intelligent architecture can effectively improve the AoI of users when the cellular network are broken in a disaster area. Unlike the traditional method, our architecture can learn through interaction with the environment, continuously optimizing the cache policy to improve cache hit rate and system performance. Specifically, we first model the emergency service process of the satellite as a Markov process. Then, we apply the advantage actor-critic (A2C) algorithm to obtain the optimal satellite cache strategy. By extensive simulation results, we can verify that the proposed intelligent architecture outperforms the existing traditional methods. © 2023 IEEE.

关键词： Satellites

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Learning Modality-Invariant Feature for Multimodal Image Matching via Knowledge Distillation

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IEEE Transactions on Geoscience and Remote Sensing 2025年 63卷

作者： Liu, Yepeng Lai, Wenpeng Gu, Yuliang Xia, Gui-Song Du, Bo Xu, Yongchao Wuhan University National Engineering Research Center for Multimedia Software Institute of Artificial Intelligence School of Computer Science Hubei Key Laboratory of Multimedia and Network Communication Engineering Wuhan430070 China SF Technology Co. Ltd Shenzhen518000 China

Multimodal remote sensing image matching is essential for multi-source information fusion. Recently, learning-based feature matching networks have significantly enhanced the performance of unimodal image matching tasks through data-driven approaches. However, progress in applying these learning-based methods to multimodal image matching has been slower. A major obstacle is the substantial nonlinear radiometric differences between modalities, which require networks to learn modality-invariant features from large amounts of paired data. To address this, we propose EMINet, an efficient method for learning modality-invariant features from limited data to improve matching performance. Our approach constructs a high-performance teacher network by combining the DINOv2 foundational model, the keypoint and descriptor extraction network SuperPoint, and the feature matching network SuperGlue. Leveraging the strong semantic representation capability of DINOv2, the teacher network achieves excellent cross-modality matching ability. To meet low-latency requirements in practical applications, we introduce two novel knowledge distillation strategies: Semantic Window Relation Distillation (SWRD) and Cross-Triplet Descriptor Distillation (CTDD). SWRD improves the discriminative power of the student network’s descriptors by learning patch-level distributions from DINOv2, while CTDD enforces cross-modality triplet constraints to enhance modality invariance of the student network. Experimental results demonstrate that EMINet outperforms several state-of-the-art methods on various datasets, including Optical-SAR, Optical-NIR, and Optical-IR datasets. © 1980-2012 IEEE.

关键词： Teaching

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CHRT:Clustering-Based Hybrid Re-Routing System for Traffic Congestion Avoidance

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China communications 2021年第7期18卷 86-102页

作者： Jie Huo Xiangming Wen Luning Liu Luhan Wang Meiling Li Zhaoming Lu Beijing Laboratory of Advanced Information Networks and Beijing Key Laboratory of Network System Architecture and ConvergenceSchool of Information and Communication EngineeringBeijing University of Posts and TelecommunicationsBeijing 100876China Witcomm Open Source Communication Research Institute Beijing 100088China Taiyuan University of Science and Technology Taiyuan 030024China

Re-routing system has become an important technology to improve traffic *** traditional re-routing schemes do not consider the dynamic characteristics of urban traffic,making the planned routes unable to cope with the changing traf-fic *** on real-time traffic information,it is challenging to dynamically re-route connected vehicles to alleviate traffic ***,how to obtain global traffic information while reducing communication costs and improving travel efficiency poses a challenge to the re-routing *** deal with these challenges,this paper proposes CHRT,a clustering-based hybrid re-routing system for traffic congestion *** develops a multi-layer hybrid *** central server accesses the global view of traffic,and the distributed part is composed of vehicles divided into clusters to reduce latency and communication ***,a clustering-based priority mechanism is proposed,which sets priorities for clusters based on realtime traffic information to avoid secondary ***,to plan the optimal routes for vehicles while alleviating global traffic congestion,this paper presents a multi-metric re-routing *** extensive simulations based on the SUMO traffic simulator,CHRT reduces vehicle traveling time,fuel consumption,and CO2 emissions compared to other *** addition,CHRT globally alleviates traffic congestion and improves traffic efficiency.

关键词： traffic congestion dynamic re-routing intelligent transportation system(ITS) real-time traffic information VANET

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