Article
Computer Science, Hardware & Architecture
Gee Yong Suk, Soo Min Kim, Jongwoo Kwak, Sub Hur, Eunyong Kim, Chan-Byoung Chae
Summary: Researchers are exploring integrated access and backhaul (IAB) frameworks for 5G new radio (NR) as a cost-effective alternative to wired backhaul. The integration of full duplex (FD) technologies in this framework is promising, but it faces challenges such as self-interference (SI) which may impact its performance and feasibility.
IEEE WIRELESS COMMUNICATIONS
(2022)
Article
Computer Science, Information Systems
Xiangyu Pi, Pengfei Yi, Zhenyu Xiao, Wei Zhang, Zhu Han, Xiang-Gen Xia
Summary: In this letter, a novel cost-efficient transmitter conceptual design based on reconfigurable intelligent surface (RIS) with discrete phase shifts is proposed. The design utilizes the digital signal to adjust the discrete reflection coefficients of RIS, modulating the phases of the reflected carrier signal without the need for complex digital signal processing (DSP) hardware and costly radio frequency (RF) chains. A joint digital modulation and beamforming method is also developed to enable information transmission and enhance signal strength. Extensive simulation results validate the cost-effective and power-efficient solution for wireless communications provided by the novel design of RIS-assisted transmitter.
IEEE WIRELESS COMMUNICATIONS LETTERS
(2023)
Article
Computer Science, Information Systems
Zeynep Gurkas-Aydin, Serhan Yarkan
Summary: Sub-Nyquist sampling is a widely used technique in signal processing and communication technologies. Although it has some drawbacks, sub-Nyquist receivers can still provide several ways of recovering information to some extent by enhancing interpolation mechanisms.
Article
Computer Science, Information Systems
Ge Wang, Shouqian Shi, Huazhe Wang, Yi Liu, Chen Qian, Cong Zhao, Wei Xi, Han Ding, Zhiping Jiang, Jizhong Zhao
Summary: Spotlight is a concurrent rate-adaptive reading system in passive RFIDs. It effectively addresses the challenges of tag collisions, unpredictable user behaviors, and multipath-prevalent environments. Through multichannel features and real-time MU-MIMO beamforming, Spotlight achieves high-efficiency tag reading and online parallel decoding for improved throughput.
IEEE INTERNET OF THINGS JOURNAL
(2023)
Article
Computer Science, Hardware & Architecture
Jie Hu, Qing Wang, Kun Yang
Summary: This article introduces the utilization of full spectrum in 6G, proposing an energy self-sustainable 6G scheme. By exploiting technologies such as cell-free and airborne access networks, as well as intelligent reflecting surfaces, energy efficiency can be improved. Additionally, utilizing radio-frequency/visible-light signals for wireless information and energy provision enables the realization of zero-energy Internet of Everything devices.
IEEE WIRELESS COMMUNICATIONS
(2021)
Article
Computer Science, Hardware & Architecture
Robert Khasanov, Julian Robledo, Christian Menard, Andres Goens, Jeronimo Castrillon
Summary: This paper proposes a domain-specific solution based on a hybrid mapping algorithm to address the balance between flexibility and efficiency in baseband processing in cRANs. By refining the scheduling methodology, efficient mapping at the millisecond granularity is achieved, with significant improvements shown on LTE workloads at design time and runtime.
ACM TRANSACTIONS ON EMBEDDED COMPUTING SYSTEMS
(2021)
Review
Chemistry, Analytical
Sofiyah Sal Hamid, Selvakumar Mariappan, Jagadheswaran Rajendran, Arvind Singh Rawat, Nuha A. Rhaffor, Narendra Kumar, Arokia Nathan, Binboga S. Yarman
Summary: Wireless communication systems are experiencing significant development, especially with the transition from 4G to 5G. As the number of wireless devices and mobile data usage increases, there is a growing need for improvements in the current systems. CMOS transceivers are being explored to meet the requirements of the latest protocols while achieving system-on-chip integration. This review article discusses the important performance metrics for designing a CMOS power amplifier (PA) and provides an overview of the trending research on CMOS PA techniques for efficiency, linearity, and bandwidth enhancement.
Article
Engineering, Electrical & Electronic
Emil Bjornson, Lucio Marcenaro
Summary: The shape of a surface affects how wireless radio-frequency signals are reflected. By bending and rotating a metal plate or using an intelligent reflecting surface (IRS), the desired reflection of the signal can be achieved. An IRS is a 2D array of metamaterials that can electronically manipulate the reflection of the signal by varying the surface impedance.
IEEE SIGNAL PROCESSING MAGAZINE
(2022)
Article
Engineering, Electrical & Electronic
Parthiban Annamalai, Jyotsna Bapat, Debabrata Das
Summary: Hybrid IBFD cellular networks, combining Full Duplex (FD) and Half Duplex (HD) User Equipments (UEs), have the potential to significantly improve spectral efficiency. This paper proposes a location-aware technique to obtain Channel State Information (CSI) among UEs without computational and signaling overheads. By leveraging frequency sharing and optimal UE grouping, a constrained optimization problem is formulated to maximize sum-SE. The proposed solution outperforms HD systems by achieving a median sum-SE improvement of 89%.
IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
(2022)
Article
Engineering, Electrical & Electronic
Wei Fan, Mengting Li, Zhengpeng Wang, Fengchun Zhang
Summary: OTA radiated testing is becoming inevitable for future radio devices with integrated transceiver radio designs. Wireless cable solutions have attracted attention for MIMO device performance testing. The compensation of the transfer matrix between OTA probes and DUT antenna ports is implemented using radio channel emulators, but this leads to expensive systems and wasted resources. A novel wireless cable implementation is proposed to address these issues, providing a simple and cost-effective solution.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Review
Chemistry, Analytical
Rodrigo Fuchs Miranda, Carlos Henrique Barriquello, Vitalio Alfonso Reguera, Gustavo Weber Denardin, Djeisson Hoffmann Thomas, Felipe Loose, Leonardo Saldanha Amaral
Summary: This paper reviews the latest developments in cognitive hybrid RF-VLC systems and emphasizes the importance of seamless integration of CRSNs and VLC technologies in WSNs. The paper explores the complexity of this integration and highlights the potential of machine learning and deep learning methods in developing advanced cognitive radio strategies.
Article
Engineering, Electrical & Electronic
Massimiliano Maule, John Vardakas, Christos Verikoukis
Summary: Network slicing is a key technology in 5G systems that ensures service quality and optimizes resource utilization. Before commercial availability, different sections of the 5G architecture need to be modified to support network slicing. By monitoring the key performance indicators of each slice tenant, optimal service level agreements can be guaranteed.
IEEE COMMUNICATIONS MAGAZINE
(2021)
Article
Engineering, Electrical & Electronic
Luca Chiaraviglio, Sara Turco, Giuseppe Bianchi, Nicola Blefari-Melazzi
Summary: This study develops a simple model to compute the impact of cellular network densification on radio frequency pollution (RFP). The results show that when the radiated power from the base stations is adjusted to ensure a minimum sensitivity at the cell edge, cellular network densification can decrease RFP.
IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
(2022)
Article
Engineering, Electrical & Electronic
Preksha Jain, Akhil Gupta, Neeraj Kumar, Mohsen Guizani
Summary: With the evolution of wireless systems, the number of wireless communication devices has grown exponentially. The development of technologies like IoT and mMTC has also contributed to this increase. The future of wireless communication networks in the 6G era will involve ultra-dense distribution of devices with various service and rate requirements, demanding high network energy, capacity, and efficient spectrum deployment. This paper proposes the use of mMIMO and NOMA techniques, as well as millimeter Wave and Terahertz channels, to enhance network capacity. Additionally, the paper suggests the use of BS caching and an application-specific channel selection scheme in a cache-enabled two-tier 6G HetNet.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2023)
Article
Computer Science, Hardware & Architecture
Payam Heydari, Huan Wang, Hossein Mohammadnezhad, Peyman Nazari
Summary: With the rise of 5G technology, portable computing devices capable of handling multi-Gb/s data rates are expected to enter the wireless market. The recent allocation of above-100-GHz band by the Federal Communications Commission presents a great opportunity for the development of high-speed wireless networks. Novel transceiver architectures are needed to address the increasing demand for higher data rates.
IEEE WIRELESS COMMUNICATIONS
(2021)
Article
Engineering, Electrical & Electronic
Yuna Jiang, Jiawen Kang, Dusit Niyato, Xiaohu Ge, Zehui Xiong, Chunyan Miao, Xuemin Shen
Summary: The metaverse provides a virtual space for people to interact through digital avatars, but real-time rendering is a key challenge. This paper proposes a hierarchical game-theoretic CDC framework for metaverse services, particularly for vehicular metaverse. The framework utilizes idle resources from vehicles as CDC workers to handle intensive computation tasks.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Meng Lei, Qiang Li, Xiaohu Ge, Ashish Pandharipande
Summary: In this paper, edge caching in fog radio access networks subject to dynamic content popularity is investigated. A federated deep reinforcement learning (FDRL) framework is proposed to improve the long-term cache-hit-ratio (CHR), where multiple fog access points (FAPs) adjust their caching strategies under the coordination of a central server (CS). To overcome the performance loss caused by maintaining a global model at the CS, a partially collaborative caching (PCC) algorithm is introduced, which switches data training between two models at each FAP, achieving a balance between local and global characteristics. Experimental results on a real-world dataset demonstrate significant performance gains with the proposed FDRL in terms of CHR. Moreover, the proposed PCC algorithm outperforms traditional federated learning (FL) with full collaboration among FAPs when an appropriate switching factor is used.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Yi Zheng, Cheng-Xiang Wang, Runruo Yang, Long Yu, Fan Lai, Jie Huang, Rui Feng, Chao Wang, Chao Li, Zhimeng Zhong
Summary: This paper explores the unique channel characteristics brought by ultra-massive multiple-input multiple-output (MIMO) technology through channel measurements and modeling. The non-stationarity, spherical wavefront, channel hardening, and sparse properties are validated. A general three-dimensional (3D) sixth generation (6G) non-stationary geometry-based stochastic model (GBSM) for ultra-massive MIMO communication systems is proposed. The statistical properties of channel measurements, channel model, and channel capacities are studied.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Hengtai Chang, Cheng-Xiang Wang, Ji Bian, Rui Feng, Yubei He, Yunfei Chen, El-Hadi M. Aggoune
Summary: This paper proposes a novel three-dimensional beam domain channel model for UAV communications, which takes into account the spherical wave front and array non-stationarity. The model divides the large antenna array into sub-arrays and classifies multipath components as near-field and far-field components. Channel statistical properties such as spatial-temporal-frequency correlation function, root-mean-squared Doppler spread, and beam spread are derived and simulated. The proposed model shows better temporal correlation and is equivalent to the geometry-based stochastic model in system performance evaluation.
IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
(2023)
Article
Engineering, Electrical & Electronic
Rui Feng, Cheng-Xiang Wang, Jie Huang, Xiqi Gao
Summary: In order to fully explore the potential of ultramassive MIMO communication systems, it is necessary to understand the characteristics of new ultramassive MIMO channels and establish comprehensive channel models. This article reviews recent advancements in ultramassive MIMO technologies, including wireless channel characterization and modeling, channel estimation, spatial multiplexing, and precoding. It also discusses the challenges faced by these technologies due to the increasing complexity and computing burden in ultramassive MIMO systems, and introduces the emerging trend of transforming related technologies from the traditional spatial domain to the beam domain for more efficient and systematic solutions. The benefits of large sparsity, reduced energy consumption, and improved usage of radio frequency (RF) chains in the beam domain channel are elaborated.
IEEE VEHICULAR TECHNOLOGY MAGAZINE
(2023)
Article
Computer Science, Information Systems
Minghui Pang, Qiuming Zhu, Cheng-Xiang Wang, Zhipeng Lin, Junyu Liu, Chongyu Lv, Zhuo Li
Summary: This article presents three novel stochastic probability models for the Line-of-Sight (LoS) path, ground specular (GS) path, and building scattering (BS) path in air-to-ground (A2G) communications under urban scenarios. The models take into account the geometric stochastic information of 3-D scattering environments, including the width, height, and distribution of buildings, as well as the effect of the Fresnel zone and altitudes of transceivers. Simulation results show that the proposed models have good performance and are consistent with existing models.
IEEE INTERNET OF THINGS JOURNAL
(2023)
Article
Engineering, Electrical & Electronic
Li Zhang, Cheng-Xiang Wang, Zihao Zhou, Xinyue Chen, Jie Huang, Chun Pan, El-Hadi M. Aggoune, Yang Miao
Summary: This article conducts extensive channel measurements and characteristics analysis to investigate large-scale fading (LSF) and small-scale fading (SSF) of wireless local area network (WLAN) channels in large indoor office environments. The frequency dependence of LSF, delay spread (DS), and K-factor (KF) is explored through multifrequency single-input-single-output (SISO) channel measurements. The effects of antenna half-power beamwidths (HPBWs) on LSF, DS, and KF are investigated, inspiring AP deployment in high-density (HD) scenarios. Additionally, multiple-input-multiple-output (MIMO) channel measurements are conducted to study the SSF of time nonstationarity and multilink correlation.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Engineering, Electrical & Electronic
Yubei He, Cheng-Xiang Wang, Hengtai Chang, Rui Feng, Jian Sun, Wensheng Zhang, Yang Hao, El-Hadi M. Aggoune
Summary: In this paper, a 3-dimensional non-stationary geometry-based stochastic model is proposed for maritime massive MIMO communication systems. A novel beam domain channel model is then proposed, which transforms the corresponding stochastic model from the array domain to the beam domain. Two methods are used to characterize the array non-stationarity, and important channel statistical properties are studied and compared based on the proposed models.
IEEE TRANSACTIONS ON COMMUNICATIONS
(2023)
Article
Engineering, Electrical & Electronic
Boyu Hua, Haoran Ni, Qiuming Zhu, Cheng-Xiang Wang, Tongtong Zhou, Kai Mao, Junwei Bao, Xiaofei Zhang
Summary: This paper proposes a three-dimensional non-stationary hybrid model for UAV-to-ground channel in order to capture the channel characteristics of UAV's 3D trajectory, posture variation, and fuselage scattering effect. The channel parameters are generated using machine learning and ray tracing techniques, and the impact of posture variation and fuselage scattering on statistical properties is analyzed. The validity of the proposed model is verified by comparing simulation results with measured ones.
IEEE TRANSACTIONS ON COMMUNICATIONS
(2023)
Article
Engineering, Electrical & Electronic
Yi Zheng, Cheng-Xiang Wang, Jie Huang, Rui Feng, John Thompson
Summary: This paper conducts ultra-massive MIMO channel measurements at 5.3 GHz, exploring different antenna array configurations and measurement scenarios. It studies the statistical properties of ultra-massive MIMO channels and investigates specific channel characteristics, validated by channel measurements. The results of this research are of great importance for the deployment of ultra-massive MIMO communication systems.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2023)
Article
Computer Science, Information Systems
Yuwei Le, Xintong Ling, Jiaheng Wang, Ruiwei Guo, Yongming Huang, Cheng-Xiang Wang, Xiaohu You
Summary: Blockchain radio access network (B-RAN) has emerged as an innovative paradigm for 6G wireless communications, providing diverse wireless services and applications through secure and efficient resource sharing and trading. This study aims to establish a unified architecture with enhanced efficiency, security, compatibility, and flexibility for resource sharing and trading in B-RAN.
IEEE INTERNET OF THINGS JOURNAL
(2023)
Article
Computer Science, Information Systems
Xuan Zhu, Yang Liu, Cheng-Xiang Wang
Summary: This letter proposes a novel MIMO channel estimation scheme based on the assumption of spherical wavefront. The large antenna array is divided into sub-arrays, and channel estimation is performed using orthogonal matching pursuit algorithm for each sub-array. The joint estimation of AoAs and AoDs is transformed into separate estimation through dimensionality reduction, and an iterative estimation using Taylor expansion is applied to recover the AoAs/AoDs. Numerical simulations verify the superiority of the proposed algorithm, which exhibits the best NMSE performance compared to existing methods.
IEEE WIRELESS COMMUNICATIONS LETTERS
(2023)
Article
Computer Science, Information Systems
Tuo Wu, Cunhua Pan, Yijin Pan, Hong Ren, Maged Elkashlan, Cheng-Xiang Wang
Summary: In this study, we investigate the positioning problem of multiple mobile users (MUs) in millimeter wave (mmWave) systems aided by reconfigurable intelligent surface (RIS). We propose a novel residual convolution network regression (RCNR) learning algorithm to estimate the 3D position of the MUs with higher accuracy by processing the space-time channel response vector (STCRV) as a novel type of fingerprint. Extensive simulations demonstrate that the proposed RCNR algorithm outperforms the traditional convolution neural network (CNN).
IEEE WIRELESS COMMUNICATIONS LETTERS
(2023)
Article
Computer Science, Information Systems
Cheng-Xiang Wang, Xiaohu You, Xiqi Gao, Xiuming Zhu, Zixin Li, Chuan Zhang, Haiming Wang, Yongming Huang, Yunfei Chen, Harald Haas, John S. Thompson, Erik G. Larsson, Marco Di Renzo, Wen Tong, Peiying Zhu, Xuemin Shen, H. Vincent Poor, Lajos Hanzo
Summary: 5G has been commercially deployed, providing new services and improved user experiences to users, and offering novel opportunities to various industries. However, it still faces challenges, leading to research on 6G wireless communication systems by international organizations. This paper comprehensively presents the vision, technical requirements, and application scenarios of 6G, critically evaluates its network architecture and key technologies, introduces existing testbeds and advanced verification platforms, and identifies future research directions and open challenges.
IEEE COMMUNICATIONS SURVEYS AND TUTORIALS
(2023)
Article
Education & Educational Research
Alan Huang, Markus Klein, Anna Beck
Summary: This study investigated how student teachers on a Scottish teacher education programme learn by reflecting on professional dialogue experiences. The results showed that the thought, discourse and social-affective dimensions of professional dialogue are inter-related. Furthermore, both student teachers' personal background and their learning context may be related to the approaches to professional learning.
PROFESSIONAL DEVELOPMENT IN EDUCATION
(2023)
