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Energy-efficient design for mmW ave-enabled NOMA-UAV networks

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Science China(Information Sciences) 2021年第4期64卷 40-53页

作者： Xiaowei PANG Jie TANG Nan ZHAO Xiuyin ZHANG Yi QIAN School of Information and Communication Engineering Dalian University of Technology School of Electronic and Information Engineering South China University of Technology Department of Electrical and Computer Engineering University of Nebraska-Lincoln

Owing to the recent advances of non-orthogonal multiple access(NOMA) and millimeter-wave(mmWave), these two technologies are combined in unmanned aerial vehicle(UAV) networks in this ***, energy efficiency has become a significant metric for UAVs owning to their limited energy. Thus, we aim to maximize the energy efficiency for mmWave-enabled NOMA-UAV networks by optimizing the UAV placement, hybrid precoding and power allocation. However, the optimization problem is complicated and intractable, which is decomposed into several sub-problems. First, we solve the UAV placement problem by approximating it into a convex one. Then, the hybrid precoding with user clustering is performed to better reap the multi-antenna gain. Particularly, three schemes are proposed, where the cluster head selection algorithm is adopted while considering different equivalent channels of users. Finally, the power allocation is optimized to maximize the energy efficiency, which is converted to convex and solved via an iterative algorithm. Simulation results are provided to evaluate the performance of the proposed schemes.

关键词： energy efficiency hybrid precoding millimeter-wave non-orthogonal multiple access placement optimization power allocation unmanned aerial vehicle

Application of NOMA for cellular-connected UAVs:opportunities and challenges

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Science China(Information Sciences) 2021年第4期64卷 26-39页

作者： Wee Kiat NEW Chee Yen LEOW Keivan NAVAIE Yanshi SUN Zhiguo DING Wireless Communication Centre School of Electrical Engineering Faculty of EngineeringUniversiti Teknologi Malaysia Key Laboratory of Wireless-Optical Communications Chinese Academy of SciencesSchool of Information Science and Technology University of Science and Technology of China School of Electrical and Electronic Engineering The University of Manchester School of Computing and Communications Lancaster University

Unmanned aerial vehicles(UAVs) have gained considerable interests in numerous civil applications. To push forward its potentials, cellular-connected UAVs have been introduced. Nevertheless, cellular networks face several bottlenecks such as spectrum scarcity and limited concurrent connectivity. To address these issues, non-orthogonal multiple access(NOMA) can be adopted. NOMA provides several opportunities for cellular-connected UAVs such as larger rate region, balanced performance between system throughput and fairness, and reduced delay. In this paper, we review important findings of the related studies, and outline new opportunities and challenges in NOMA for cellular-connected UAVs. Monte-Carlo simulations are then performed to analyze the new aerial user’s(AU)’s signal characteristics and evaluate the NOMA performance for co-existence of AU and terrestrial user(TU). Our preliminary results show that NOMA is a promising strategy for cellular-connected UAVs.

关键词： cellular-connected UAVs non-orthogonal multiple access signal characteristics aerial user rate terrestrial user rate

Key techniques for 5G wireless communications:network architecture, physical layer,and MAC layer perspectives

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Science China(Information Sciences) 2015年第4期58卷 5-24页

作者： MA Zheng ZHANG ZhengQuan DING ZhiGuo FAN PingZhi LI HengChao Provincial Key Lab of Information Coding and Transmission Southwest Jiaotong University Department of Communication Systems Lancaster University

The fourth generation(4G) mobile communication systems are offering service worldwide *** 4G systems could be loaded with much more services and data than previous systems, there is still a dramatic gap between the people’s practical requirements and what can be offered by the 4G ***, the research and development for the fifth generation(5G) systems have already been started. This article presents an overview of potential network architecture and highlights several promising techniques which could be employed in the future 5G systems. These techniques include non-orthogonal multiple access(NOMA),massive multiple input and multiple output(MIMO), cooperative communications and network coding, full duplex(FD), device-to-device(D2D) communications, millimeter wave communications, automated network organization, cognitive radio(CR), and green communications. The state-of-art and implementation issue of these techniques are also addressed.

关键词： 5G software defined network non-orthogonal multiple access massive MIMO full duplex deviceto-device communications millimeter wa

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Layered D2D NOMA

China Communications 2021年第1期18卷 33-42页

作者： Jinjuan Ju Jinyuan Gu Guan Zhang School of Information Science and Technology Nantong UniversityNantong 226019China School of Electronic and Information Engineering Nantong Vocational UniversityNantong 226007China

This paper investigates a layered power allocation(PA)non-orthogonal multiple access(NOMA)scheme for device-to-device(D2D)relaying networks,where the strategy of partial data transmission at relay nodes are adopted to improve the efficiency of *** addition,to satisfy different quality-of-service(QoS)requirements from multiple users,layered and grouped manners are ***,the closed-form expressions in terms of the sum-rate(SR)and outage probability of the proposed scheme are derived for independent Rayleigh fading channels,which demonstrates our theoretical *** analytical and simulation results are provided to show the superiority of our proposed scheme compared with existing works.

关键词： non-orthogonal multiple access deviceto-device sum-rate outage probability

NOMA-Aided Generalized Pre-Coded Quadrature Spatial Modulation for Downlink Communication Systems

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China Communications 2020年第11期17卷 120-130页

作者： Jun Li Jia Hou Lisheng Fan Yier Yan Xue-Qin Jiang Han Hai Research Center of Intelligent Communication Engineering School of Electronics and Communication EngineeringGuangzhou UniversityGuangzhou 510006China School of Electronic and Information Engineering Soochow UniversitySuzhou 215006China School of Computer Science Guangzhou UniversityGuangzhou 510006China School of Information Science and Technology Donghua UniversityShanghai 201620China

Generalised pre-coding quadrature spatial modulation(GPQSM)is recently proposed to increase the spectral efficiency(SE)of GPSM,which extends the transmitted symbols into in-phase/quadrature *** this paper,a novel scheme named non-orthogonal multiple access(NOMA)-aided GPQSM(NOMA-GPQSM),which incorporates the GPQSM scheme into the multi-user communication networks with assist of NOMA,is proposed to further improve the SE and system *** NOMA-GPQSM,one base station(BS)is set to serve K users,where user 1 is closest to the BS,and user K is farthest from the *** addition,a low-complexity detection method is proposed to reduce the high detection complexity of the maximum-likelihood(ML)detection in successive interference cancellation(SIC)method for all users by *** theoretical analysis of the BER performance for all users is also *** results show that near users achieve relatively good performance,and far users achieve acceptable performance by adjusting power factors for all users in NOMA-GPQSM.

关键词： spatial modulation index modulation non-orthogonal multiple access bit error rate pre-coding

Research on User Pairing Techniques Based on NOMA in Cognitive Radio Networks

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Journal of Computer and Communications 2023年第3期11卷 131-145页

作者： Yongming Huang Xiaoli He Yuxin Du School of Computer Science and Engineering Sichuan University of Science and Engineering Zigong China

This paper outlined a non-orthogonal multiple access (NOMA) grouping transmission scheme for cognitive radio networks. To address the problems of small channel gain difference of the middle part users caused by the traditional far-near pairing algorithm, and the low transmission rate of the traditional orthogonal multiple access (OMA) transmission, a joint pairing algorithm was proposed, which provided multiple pairing schemes according to the actual scene. Firstly, the secondary users were sorted according to their channel gain, and then different secondary user groups were divided, and the far-near pairing combined with (Uniform Channel Gain Difference (UCGD) algorithm was used to group the secondary users. After completing the user pairing, the power allocation problem was solved. Finally, the simulation data results showed that the proposed algorithm can effectively improve the system transmission rate.

关键词： Cognitive Radio non-orthogonal multiple access User Grouping Power Allocation

Robust Artificial Noise-Aided Beamforming for A Secure MISO-NOMA Visible Light Communication System

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China Communications 2020年第11期17卷 42-53页

作者： Xiaodong Liu Zezong Chen Yuhao Wang Fuhui Zhou Shuai Ma School of Electronic Information Wuhan UniversityWuhan 430072China School of Information Engineering Nanchang UniversityNanchang 330031China College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210000China School of Information and Control Engineering China University of Mining and TechnologyXuzhou 221116China Shanxi Key Laboratory of Information Communication Network and Security Xi’an University of Posts&TelecommunicationsXi’an 710121China

Visible light communication(VLC)and non-orthogonal multiple access(NOMA)have been deemed two promising techniques in the next wireless communication *** this paper,secure communications in the presence of potential eavesdropper are investigated for a multiple-input single-output VLC system with *** artificial noise jamming and beamforming technologies are applied to improve secure performance.A robust resource allocation scheme is proposed to minimize the total transmit power taking into account the constraints on the quality of service requirement of the desired users and the maximum tolerable data rate of the eavesdropper,and the practical imperfect channel state information of both the desired users and the *** formulated non-convex optimization problem is tackled based onS-Procedure and semi-definite programming *** results illustrate that our proposed resource allocation scheme can effectively guarantee communication security and achieve transmit power ***,the height and number of LED can significantly affect system performance and the optimum LED height can be obtained for different LED numbers.

关键词： artificial noise non-orthogonal multiple access physical-layer secrecy robust resource allocation visible light communication

Secure Transmission for NOMA Systems with Imperfect SIC

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China Communications 2020年第11期17卷 67-78页

作者： Zhongwu Xiang Xiaobing Tong Yueming Cai College of Communications Engineering Army Engineering University of PLANanjing 210007China National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of EngineeringWuhan 430033China

This paper investigates secure transmission for non-orthogonal multiple access(NOMA)systems where the imperfect successive interference cancellation(SIC)is considered at both legitimate users and eavesdropper(Eve).A power allocation scheme is designed for the legitimate users to mitigate the effect of the SIC error caused by imperfect *** characterizing the secrecy performance of the NOMA system,the closed-form expressions for connection outage probability(COP),secrecy outage probability(SOP),and effective secrecy throughput(EST)are derived over Nakagami-m fading channels in both NOMA and benchmark orthogonal multiple access(OMA)*** also provide security and reliability trade-off results(SRT)for the users in the NOMA and OMA *** results verify our analysis and show that the strong users achieve better secrecy performance but worse reliability performance and NOMA outperforms OMA in terms of SRT.

关键词： physical layer security non-orthogonal multiple access imperfect SIC security and reliability trade-off

Active User and Data Detection for Uplink Grant-free NOMA Systems

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China Communications 2020年第11期17卷 12-28页

作者： Donghong Cai Jinming Wen Pingzhi Fan Yanqing Xu Lisu Yu 无 The College of Cyber Security Jinan UniversityGuangzhou 510632China The Institute of Mobile Communications Southwest Jiaotong UniversityChengdu 610031China The State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China The School of Information Engineering Nanchang UniversityNanchang 330031China

This paper proposes some low complexity algorithms for active user detection(AUD),channel estimation(CE)and multi-user detection(MUD)in uplink non-orthogonal multiple access(NOMA)systems,including single-carrier and multi-carrier *** particular,we first propose a novel algorithm to estimate the active users and the channels for single-carrier based on complex alternating direction method of multipliers(ADMM),where fast decaying feature of non-zero components in sparse signal is *** importantly,the reliable estimated information is used for AUD,and the unreliable information will be further handled based on estimated symbol energy and total accurate or approximate number of active ***,the proposed algorithm for AUD in single-carrier model can be extended to multi-carrier case by exploiting the block sparse ***,we propose a low complexity MUD detection algorithm based on alternating minimization to estimate the active users’data,which avoids the Hessian matrix *** convergence and the complexity of proposed algorithms are analyzed and discussed *** results show that the proposed algorithms have better performance in terms of AUD,CE and ***,we can detect active users perfectly for multi-carrier NOMA system.

关键词： non-orthogonal multiple access massive connection active user detection channel estimation multi-user detection and alternating direction method of multipliers