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IEEE Conference on Wireless Communications and networking

作者： Keliang Du Luhan Wang Zishen Zhu Yunan Yan Xiangming Wen Beijing Laboratory of Advanced Information Networks BUPT Beijing China Beijing Key Laboratory of Network System Architecture and Convergence BUPT Beijing China

Software Defined network (SDN) and network Function Virtualization (NFV) technologies have driven mobile communication networks to evolve toward a Service-Based architecture (SBA) with great flexibility to meet the highly-dynamic requirements of vertical applications. The SBA has been applied into 5 th Generation (5G) core network and is evolving toward service-based end-to-end networks including virtualized Radio Access networks (vRANs). This paper proposes a converged SBA (cSBA) to decouple access, control, and data planes. Specifically, the access plane with Distributed Units (DUs) functionalities is responsible for accessing User Equipments (UEs); the control plane consists of newly-defined converged services by integrating functionalities of Central Unit Control Planes (CU-CPs) and 5G core network for signaling processing; the data plane comprises Central Unit User Planes (CP-UPs) and User Plane Functions (UPFs), which are responsible for service data transmission. Optional converged services definition, service-based interface implementation, and cognitive service framework are proposed to enable an efficient cSBA. Finally, we evaluate the performance of the cSBA against the monolithic architecture.

关键词： Protocols 5G mobile communication Process control Computer architecture Media Access Protocol network function virtualization Synchronization

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A Satellite-Terrestrial Integrated network architecture Based on Stateless Core network

A Satellite-Terrestrial Integrated Network Architecture Base...

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International Conference on Computer and Communications (ICCC)

作者： Shaoxin Huang Luhan Wang Xiangming Wen Yu Liu Haiwen Niu Beijing Laboratory of Advanced Information Networks Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing China

Comprehensive coverage is a natural advantage of satellites, and loading the functions of base station on satellites can expand the service range of Satellite-Terrestrial Integrated network(STIN), providing users with extensive and efficient access services. However, the management and control capabilities of satellite networks are inadequate, and this aspect has not been well investigated. The signalling from the control plane needs to be routed over the backhaul links to the Terrestrial Core network(TCN) for processing which increases the service latency. In this paper, we propose a novel integrated core network architecture where satellites simultaneously have access and control capabilities by provisioning next-generation NodeB(gNB) and some core network functions. Considering the constrained satellite resources, we design a lightweight Stateless Satellite Core network (SSCN) to enhance the flexibility and stability of the satellite network control. Meanwhile, based on SSCN, we redesign the registration, session establishment, and handover procedures to support mobility management and further reduce service latency. Simulation results show that the proposed integrated core network architecture improves the stability of mobility management and optimizes the network latency compared to the Non-Terrestrial network(NTN) architecture in that satellites act as radio access networks only.

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Deep Joint Source-Channel Coding Based on Semantics of Pixels for Wireless Image Transmission

Deep Joint Source-Channel Coding Based on Semantics of Pixel...

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IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC)

作者： Qizheng Sun Caili Guo Yang Yang Rui Tang Chuanhong Liu Beijing Key Laboratory of Network System Architecture and Convergence Beijing Laboratory of Advanced Information Networks Beijing University of Posts and Telecommunications Beijing China

Current image coding methods for semantic communication typically concentrate on intelligent tasks or image reconstruction separately, and seldom consider both aspects simultaneously. To balance these two aspects during wireless image transmission, we propose a joint source-channel coding method based on the semantics of pixels (SP), which can retain both pixel information for reconstruction and semantic information for intelligent tasks. Specifically, we first design a gradient-based mechanism to quantify the semantic importance of downstream intelligent tasks on pixels. Then, we design the SP-based loss function to train the deep joint source-channel coding network. Experiment results demonstrate that the proposed method maintains reconstruction performance and improves the task performance by 1.61% and 4.06%, respectively, compared to the state-of-the-art deep joint source-channel coding method and traditional separate source-channel coding method at the same transmission rate and signal-to-noise ratio.

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Importance-Aware Image Segmentation-based Semantic Communication for Autonomous Driving

arXiv

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arXiv 2024年

作者： Lv, Jie Tong, Haonan Pan, Qiang Zhang, Zhilong He, Xinxin Luo, Tao Yin, Changchuan School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing100876 China Beijing Key Laboratory of Network System Architecture and Convergence Beijing100876 China

This article studies the problem of image segmentation-based semantic communication in autonomous driving. In real traffic scenes, detecting the key objects (e.g., vehicles, pedestrians and obstacles) is more crucial than that of other objects to guarantee driving safety. Therefore, we propose a vehicular image segmentation-oriented semantic communication system, termed VIS-SemCom, where image segmentation features of important objects are transmitted to reduce transmission redundancy. First, to accurately extract image semantics, we develop a semantic codec based on Swin Transformer architecture, which expands the perceptual field thus improving the segmentation accuracy. Next, we propose a multi-scale semantic extraction scheme via assigning the number of Swin Transformer blocks for diverse resolution features, thus highlighting the important objects’ accuracy. Furthermore, the importance-aware loss is invoked to emphasize the important objects, and an online hard sample mining (OHEM) strategy is proposed to handle small sample issues in the dataset. Experimental results demonstrate that the proposed VIS-SemCom can achieve a coding gain of nearly 6 dB with a 60% mean intersection over union (mIoU), reduce the transmitted data amount by up to 70% with a 60% mIoU, and improve the segmentation intersection over union (IoU) of important objects by 4%, compared to traditional transmission scheme. © 2024, CC BY-NC-SA.

关键词： Autonomous vehicles

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A Low-Latency Routing Scheme with Traffic Balancing for LEO Satellite networks

A Low-Latency Routing Scheme with Traffic Balancing for LEO ...

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International Conference on Wireless Communications and Signal Processing (WCSP)

作者： Xinhai Yu Danpu Liu Zhilong Zhang Beijing Laboratory of Advanced Information Network Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications P. R. China

Low Earth Orbit (LEO) satellites play an important role in satellite networks owing to low-cost, low round-trip delay and high data rate. However, the rapid change of constellation topology makes routing an intractable problem. In a scenario where LEO satellite network serves communication between ground stations (GSs), we adopt virtual topology to shield the dynamics and develop an approach of unipath routing with aim to minimize the total latency of all packets. Inspired by queuing theory, we propose a new routing metric that jointly considers propagation, transmission and queuing latency, which is helpful for traffic distribution awareness and balancing. In addition, Routing Algorithm with Queuing Metric (RAQM) is proposed to calculate the route. Moreover, we have contributed to clarifying the routing latency of packets in detail and quantifying the ability of the constellation to support the traffic load. The simulation results show that the proposed scheme has advantages especially under the condition of heavy traffic load as it can effectively reduce queuing time and end-to-end latency. Furthermore, the proposed scheme can support up to 115% more traffic and avoid network congestion effectively when compared to the selected benchmarks.

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Multi-IRS Assisted Multi-UAV Wireless Resource Allocation and Deployment Optimization

Multi-IRS Assisted Multi-UAV Wireless Resource Allocation an...

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IEEE International Conference on Communications in China (ICCC)

作者： Lianwen Zhang Zhiqun Hu Zhaoming Lu Yujing Zhang Beijing Key Laboratory of Network System Architecture and Convergence China Beijing Laboratory of Advanced Information Networks Beijing University of Posts and Telecommunications China

Unmanned aerial vehicle (UAV) used as the aerial base station, can provide flexible and reliable data transmission service for designated areas, owing to its advantages of mobility, easy deployment and cost-effectiveness. However, the limited endurance of UAV, caused by its small size and payload limitation, significantly affects the quality of UAV base station (BS) network. In this study, we employ multiple intelligent reflecting surfaces (IRSs) to enhance the performance of multi-UAV BS network through collaborative adjustment of the phase shift matrix of the IRS, where UAVs can benefit from all IRSs in the region, leading to a significant increase in the network capacity. We formulate an optimization problem which aims to maximize the downlink sum-rate of the network by optimizing UAV-user association, transmit beamforming at UAVs, phase shifts of IRSs and UAVs’ locations. Considering the non-convexity of the original problem, we use Lagrangian dual transform and quadratic transform (QT) techniques to simplify the problem. Then we proposed an algorithm, named SLOTC, which combines successive refinement method, Lagrange multiplier method, oblique manifold method and Taylor-conjugate gradient method, to solve the simplified problem. Our proposed algorithm significantly outperforms existing benchmark schemes, as demonstrated by numerical results.

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Deadline-Aware Hybrid HARQ Scheme for Multi-devices Deterministic Transmission over 5G-TSN systems

Deadline-Aware Hybrid HARQ Scheme for Multi-devices Determin...

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International Conference on Wireless Communications and Signal Processing (WCSP)

作者： Jian Zhao Tao Wang Haonan Tong Xinxin He Changchuan Yin Beijing Laboratory of Advanced Information Network Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications P. R. China

This paper studies a deadline-aware hybrid retransmission scheme for an Industrial Internet of Things (IIoT) system over the 5th generation and Time-Sensitive networking (5G-TSN) system. In the considered model, multiple devices must transmit time-sensitive data flows to an edge server for real-time computing and industrial control. These scenarios require the 5G-TSN technique to realize deterministic transmission, which must complete the data transmission before the specified deadline while maintaining ultra-high reliability. Since the uncertainty of the wireless channel in 5G-TSN affects the transmission reliability, hybrid automatic repeat request (HARQ) technology is introduced to improve the transmission success probability. However, two existing mainstream HARQ negative acknowledgment-based (NACK-based) and blind schemes lead to a huge delay penalty and drain spectrum resources, respectively. These drawbacks make it challenging to meet multiple devices’ diverse quality of service (QoS) requirements. To address this issue, a deadline-aware hybrid HARQ scheme that combines NACK and blind retransmission schemes is proposed to maximize the number of successfully transmitted deterministic data flows over the 5G-TSN. Specifically, we first propose the delay and reliability models for our considered 5G-TSN IIoT system. Subsequently, our proposed scheme is introduced in detail. The simulation results demonstrate that the proposed scheme can increase the number of deterministic transmission flows by 170.52% and 27.98% with 100 devices compared to 1) single NACK-based and 2) traditional hybrid HARQ schemes.

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Spatial-Temporal Alignment via Optimal Transport for Video-Text Retrieval

Spatial-Temporal Alignment via Optimal Transport for Video-T...

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2022 IEEE International Conference on Multimedia and Expo, ICME 2022

作者： Feng, Zerun Zeng, Zhimin Guo, Caili Li, Zheng Zhang, Yufeng School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing Key Laboratory of Network System Architecture and Convergence Beijing China Beijing Laboratory of Advanced Information Networks Beijing China China Telecom Dict Application Capability Center China

ISBN: (数字)9781665485630

ISBN: (纸本)9781665485630

Video-text retrieval is one of the most popular branches in the cross-modal research area facing the exponential growth of multimedia services. Present methods typically mea-sure cross-modal similarities only by the cosine metric in a common space. However, this function ignores the in-herent discrepancy between videos and texts for reflecting spatial-temporal contents and fails to align them under the weakly supervised setting. To address this issue, we propose a novel Spatial-Temporal Optimal Transport (STOT) frame-work building upon advances in optimal transport. The spatial and temporal characteristics of videos and texts are carefully considered in STOT and associated by calculating a spatial-temporal alignment distance, which can be implemented as a regularizer for existing models to improve retrieval accu-racy. Extensive experiments are conducted on two video-text datasets with two models as base architectures to demonstrate the outperformance of our framework due to the powerful spatial-temporal alignment capability. © 2022 IEEE.

关键词： Multimedia services

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Demonstration of Time Redundancy Mechanism for Deterministic Communications over Hybrid networks

Demonstration of Time Redundancy Mechanism for Deterministic...

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OptoElectronics and Communications Conference, OECC

作者： Hongxing Li Guochu Shou State Key Laboratory of Networking and Switching Technology 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

We propose a time redundancy mechanism to enhance the determinism of 5G TSN hybrid networks, and experimentally demonstrate the most cost-effective enhancement occurs when frame is replicated four times with 42% maxim... 详细信息

ISBN: (数字)9798350308396

ISBN: (纸本)9798350308402

关键词： 5G mobile communication Redundancy Jitter

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Deep Joint Source-Channel Coding for Wireless Image Transmission with Semantic Importance

arXiv

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arXiv 2023年

作者： Sun, Qizheng Guo, Caili Yang, Yang Chen, Jiujiu Tang, Rui Liu, Chuanhong Beijing University of Posts and Telecommunications Beijing Key Laboratory of Network System Architecture and Convergence Beijing Laboratory of Advanced Information Networks Beijing100876 China

The sixth-generation mobile communication system proposes the vision of smart interconnection of everything, which requires accomplishing communication tasks while ensuring the performance of intelligent tasks. A joint source-channel coding method based on semantic importance is proposed, which aims at preserving semantic information during wireless image transmission and thereby boosting the performance of intelligent tasks for images at the receiver. Specifically, we first propose semantic importance weight calculation method, which is based on the gradient of intelligent task’s perception results with respect to the features. Then, we design the semantic loss function in the way of using semantic weights to weight the features. Finally, we train the deep joint source-channel coding network using the semantic loss function. Experiment results demonstrate that the proposed method achieves up to 57.7% and 9.1% improvement in terms of intelligent task’s performance compared with the source-channel separation coding method and the deep source-channel joint coding method without considering semantics at the same compression rate and signal-to-noise ratio, respectively. Copyright © 2023, The Authors. All rights reserved.

关键词： Semantics

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