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Found 130 papers, 5 papers with code
GLUSE: Enhanced Channel-Wise Adaptive Gated Linear Units SE for Onboard Satellite Earth Observation Image Classification
This study introduces ResNet-GLUSE, a lightweight ResNet variant enhanced with Gated Linear Unit-enhanced Squeeze-and-Excitation (GLUSE), an adaptive channel-wise attention mechanism.
Secure Communications for All Users in Low-Resolution IRS-aided Systems Under Imperfect and Unknown CSI
In real-life scenarios, due to hardware limitations of the IRS' passive reflective elements (PREs), the use of a full-resolution (continuous) phase shift (CPS) is impractical.
UAV-Assisted 5G Networks: Mobility-Aware 3D Trajectory Optimization and Resource Allocation for Dynamic Environments
This paper proposes a framework for robust design of UAV-assisted wireless networks that combine 3D trajectory optimization with user mobility prediction to address dynamic resource allocation challenges.
Minimum Mean Squared Error Holographic Beamforming for Sum-Rate Maximization
This paper studies the problem of hybrid holographic beamforming for sum-rate maximization in a communication system assisted by a reconfigurable holographic surface.
Enhancing Physical Layer Security in Cognitive Radio-Enabled NTNs with Beyond Diagonal RIS
We formulate a joint optimization problem to maximize the secrecy rate by optimizing BD-RIS phase shifts and the secondary transmitter power allocation while controlling the interference temperature from the secondary network to the primary network.
A Semantic-Loss Function Modeling Framework With Task-Oriented Machine Learning Perspectives
The integration of machine learning (ML) has significantly enhanced the capabilities of Earth Observation (EO) systems by enabling the extraction of actionable insights from complex datasets.
Survey on Beyond Diagonal RIS Enabled 6G Wireless Networks: Fundamentals, Recent Advances, and Challenges
Beyond Diagonal Reconfigurable Intelligent Surfaces (BD-RIS) represent a groundbreaking innovation in sixth-generation (6G) wireless networks, enabling unprecedented control over wireless propagation environments compared to conventional diagonal RIS (D-RIS).
Secrecy Rate Maximization for 6G Reconfigurable Holographic Surfaces Assisted Systems
Reconfigurable holographic surfaces (RHS) have emerged as a transformative material technology, enabling dynamic control of electromagnetic waves to generate versatile holographic beam patterns.
Joint Holographic Beamforming and User Scheduling with Individual QoS Constraints
Reconfigurable holographic surfaces (RHS) have emerged as a transformative material technology, enabling dynamic control of electromagnetic waves to generate versatile holographic beam patterns.
Joint Beamforming and 3D Location Optimization for Multi-User Holographic UAV Communications
This paper pioneers the field of multi-user holographic unmanned aerial vehicle (UAV) communications, laying a solid foundation for future innovations in next-generation aerial wireless networks.
Optimizing Antenna Activation for Even Power Distribution in Multi-Beam Satellite Systems Using Genetic Algorithm
This is particularly relevant for communication at 28 GHz, a key frequency in the mmWave spectrum, used for high-bandwidth satellite links and 5G communications.
A Metasurface-based Cross-slot Aperture Coupled Antenna Array for Ku-band Satellites in Reception
The demand for cost-effective, low-profile user terminals for satellite communications supporting multicast services for Geostationary Orbit (GEO) satellites, has become a key focus for many Direct-to-Home (DTH) providers where the high data rates in the downlink are required.
Holographic Joint Communications and Sensing With Cramer-Rao Bounds
To optimize the system performance, we propose a novel weighted multi-objective problem formulation that aims to simultaneously maximize the communication rate and minimize the CRBs.
Exploring Radial Symmetry on Phased Arrays Using Particle Swarm Optimization
Phased antenna arrays enable dynamic beam shaping, which is essential for Non-Geostationary (NGSO) satellite communications where efficient beam distribution is important.
Joint Communications and Sensing for 6G Satellite Networks: Use Cases and Challenges
Satellite Networks (SN) have traditionally been instrumental in providing two key services: communications and sensing.
Holographic MIMO for Next Generation Non-Terrestrial Networks: Motivation, Opportunities, and Challenges
In this article, we propose the integration of the Holographic Multiple Input Multiple Output (HMIMO) as a transformative solution for next generation Non-Terrestrial Networks (NTNs), addressing key challenges, such as high hardware costs, launch expenses, and energy inefficiency.
Semantic Knowledge Distillation for Onboard Satellite Earth Observation Image Classification
This study presents an innovative dynamic weighting knowledge distillation (KD) framework tailored for efficient Earth observation (EO) image classification (IC) in resource-constrained settings.
On-Air Deep Learning Integrated Semantic Inference Models for Enhanced Earth Observation Satellite Networks
Earth Observation (EO) systems are crucial for cartography, disaster surveillance, and resource administration.
Integration of Beyond Diagonal RIS and UAVs in 6G NTNs: Enhancing Aerial Connectivity
This work proposes the integration of unmanned aerial vehicle (UAV) communications and BD-RIS in 6G NTNs, which has the potential to further enhance wireless coverage and spectral efficiency.
Onboard Satellite Image Classification for Earth Observation: A Comparative Study of ViT Models
This study focuses on identifying the most effective pre-trained model for land use classification in onboard satellite processing, emphasizing achieving high accuracy, computational efficiency, and robustness against noisy data conditions commonly encountered during satellite-based inference.
Seamless 5G Automotive Connectivity with Integrated Satellite Terrestrial Networks in C-Band
This paper examines integrated satellite-terrestrial networks (ISTNs) in urban environments, where terrestrial networks (TNs) and non-terrestrial networks (NTNs) share the same frequency band in the C-band which is considered the promising band for both systems.
Near-Field Signal Processing: Unleashing the Power of Proximity
After nearly a century of specialized applications in optics, remote sensing, and acoustics, the near-field (NF) electromagnetic propagation zone is experiencing a resurgence in research interest.
Optimal Linear Precoding Under Realistic Satellite Communications Scenarios
To mitigate this issue, the optimal linear precoders are implemented at the gateways (GWs).
Efficient Transmission Scheme for LEO Satellite-Based NB-IoT: A Data-Driven Perspective
This study analyses the medium access control (MAC) layer aspects of a low-Earth-orbit (LEO) satellite-based Internet of Things (IoT) network.
Beyond Diagonal RIS-Aided Networks: Performance Analysis and Sectorization Tradeoff
Furthermore, closed-form expressions for the outage probability, achievable spectral and energy efficiency, symbol error probability, and diversity order for the proposed system model are derived.
Artificial Intelligence Satellite Telecommunication Testbed using Commercial Off-The-Shelf Chipsets
The Artificial Intelligence Satellite Telecommunications Testbed (AISTT), part of the ESA project SPAICE, is focused on the transformation of the satellite payload by using artificial intelligence (AI) and machine learning (ML) methodologies over available commercial off-the-shelf (COTS) AI-capable chips for onboard processing.
A Deep-NN Beamforming Approach for Dual Function Radar-Communication THz UAV
In this paper, we consider a scenario with one UAV equipped with a ULA, which sends combined information and sensing signals to communicate with multiple GBS and, at the same time, senses potential targets placed within an interested area on the ground.
An Experimental Study of C-Band Channel Model in Integrated LEO Satellite and Terrestrial Systems
Particularly, the interference channel from the low-earth-orbit (LEO) satellite to the dense urban area is analyzed carefully under the impact of the environment's characteristics, i. e., the building density, building height, and the elevation angle.
Optimizing Satellite Network Infrastructure: A Joint Approach to Gateway Placement and Routing
Satellite constellation systems are becoming more attractive to provide communication services worldwide, especially in areas without network connectivity.
Emerging NGSO Constellations: Spectral Coexistence with GSO Satellite Communication Systems
Moving onto operational aspects related to the sharing of spectrum, we introduce recent work on interference detection, identification, and mitigation and provide our vision of the emerging role of artificial intelligence (AI) in the aforementioned tasks.
Enhancing Indoor and Outdoor THz Communications with Beyond Diagonal-IRS: Optimization and Performance Analysis
This work investigates the application of Beyond Diagonal Intelligent Reflective Surface (BD-IRS) to enhance THz downlink communication systems, operating in a hybrid: reflective and transmissive mode, to simultaneously provide services to indoor and outdoor users.
User-Centric Beam Selection and Precoding Design for Coordinated Multiple-Satellite Systems
This paper introduces a joint optimization framework for user-centric beam selection and linear precoding (LP) design in a coordinated multiple-satellite (CoMSat) system, employing a Digital-Fourier-Transform-based (DFT) beamforming (BF) technique.
Interference analysis of Positioning Reference Signals in 5G NTN
Accurate asset localization holds paramount importance across various industries, ranging from transportation management to search and rescue operations.
Performance Evaluation of Neuromorphic Hardware for Onboard Satellite Communication Applications
Spiking neural networks (SNNs) implemented on neuromorphic processors (NPs) can enhance the energy efficiency of deployments of artificial intelligence (AI) for specific workloads.
Satellite Swarms for Narrow Beamwidth Applications
Satellite swarms have recently gained attention in the space industry due to their ability to provide extremely narrow beamwidths at a lower cost than single satellite systems.
Joint Computation and Communication Resource Optimization for Beyond Diagonal UAV-IRS Empowered MEC Networks
We propose a joint optimization strategy to reduce system's worst-case latency and UAV hovering time by optimizing BD-IRS-UAV deployment and resource allocation.
Genetic Algorithm-based Beamforming in Subarray Architectures for GEO Satellites
The incorporation of subarrays in Direct Radiating Arrays for satellite missions is fundamental in reducing the number of Radio Frequency chains, which correspondingly diminishes cost, power consumption, space, and mass.
Supervised Learning Based Real-Time Adaptive Beamforming On-board Multibeam Satellites
Satellite communications (SatCom) are crucial for global connectivity, especially in the era of emerging technologies like 6G and narrowing the digital divide.
Spherical Wavefront Near-Field DoA Estimation in THz Automotive Radar
In this work, we examine near-field DoA estimation for THz automotive radar.
Flexible Payload Configuration for Satellites using Machine Learning
Satellite communications, essential for modern connectivity, extend access to maritime, aeronautical, and remote areas where terrestrial networks are unfeasible.
Overview of Use Cases in Single Channel Full Duplex Techniques for Satellite Communication
This paper provides an overview of the diverse range of applications and use cases for Single-Channel Full-Duplex (SCFD) techniques within the field of satellite communication.
Connecting Space Missions Through NGSO Constellations: Feasibility Study
This paper performs a feasibility study on the concept of connecting space missions to the network through commercial mega-constellations.
ML-based PBCH symbol detection and equalization for 5G Non-Terrestrial Networks
This paper delves into the application of Machine Learning (ML) techniques in the realm of 5G Non-Terrestrial Networks (5G-NTN), particularly focusing on symbol detection and equalization for the Physical Broadcast Channel (PBCH).
Harnessing Supervised Learning for Adaptive Beamforming in Multibeam Satellite Systems
In today's ever-connected world, the demand for fast and widespread connectivity is insatiable, making multibeam satellite systems an indispensable pillar of modern telecommunications infrastructure.
Deep Reinforcement Learning for Backscatter Communications: Augmenting Intelligence in Future Internet of Things
Backscatter communication (BC) technology offers sustainable solutions for next-generation Internet-of-Things (IoT) networks, where devices can transmit data by reflecting and adjusting incident radio frequency signals.
Gateway Station Geographical Planning for Emerging Non-Geostationary Satellites Constellations
Among the recent advances and innovations in satellite communications, Non-Geostationary Orbit (NGSO) satellite constellations are gaining popularity as a viable option for providing widespread broadband internet access and backhauling services.
Terahertz-Band Direction Finding With Beam-Split and Mutual Coupling Calibration
Terahertz (THz) band is currently envisioned as the key building block to achieving the future sixth generation (6G) wireless systems.
Reconfigurable Intelligent Surfaces for 6G Non-Terrestrial Networks: Assisting Connectivity from the Sky
This paper studies the potential of RIS-integrated NTNs to revolutionize the next-generation connectivity.
Energy-Efficient On-Board Radio Resource Management for Satellite Communications via Neuromorphic Computing
The latest satellite communication (SatCom) missions are characterized by a fully reconfigurable on-board software-defined payload, capable of adapting radio resources to the temporal and spatial variations of the system traffic.
Signal Processing Based Antenna Pattern Characterization for MIMO Systems
Furthermore, it grants a much wider research community the ability to independently perform APC for emerging complex 6G antenna systems, without relying on anechoic chambers.
IRS Assisted MIMO Full Duplex: Rate Analysis and Beamforming Under Imperfect CSI
In this manuscript, we present a novel approach to jointly optimize active and passive beamforming in a multiple-input-multiple-output (MIMO) FD system assisted by an IRS for weighted sum rate (WSR) maximization.
Robust Beamforming for IRS Aided MIMO Full Duplex Systems
We also analyze the achievable WSR of an IRS-assisted FD with imperfect CSI, for which the lower and the upper bounds are derived.
Reconfigurable Intelligent Surfaces Enhanced NOMA D2D Communications Underlaying UAV Networks
The objective is to maximize the sum rate of NOMA D2D communications by simultaneously optimizing the power budget of D2D transmitter, NOMA power allocation coefficients of D2D receivers and passive beamforming of RIS while guaranteeing the quality of services of UAV user.
A Hybrid Optimization and Deep RL Approach for Resource Allocation in Semi-GF NOMA Networks
In this design, a multi-agent deep Q network (MADQN) approach is employed to conduct the subchannel assignment (SA) among users.
Harnessing the Power of Swarm Satellite Networks with Wideband Distributed Beamforming
The space communications industry is challenged to develop a technology that can deliver broadband services to user terminals equipped with miniature antennas, such as handheld devices.
RIS-Assisted Energy-Efficient LEO Satellite Communications with NOMA
Then, in step 2, given the transmit power, we design passive beamforming for RIS by solving the semi-definite programming.
Task-Oriented Communication Design at Scale
Numerical results show striking improvements in reducing the computational complexity of obtaining VoI needed for the TOCD in a MAS problem without compromising the average return performance of the MAS.
Joint Optimization of 3D Placement and Radio Resource Allocation for per-UAV Sum Rate Maximization
The main aim of this work is to derive an efficient technique for the allocation of radio resources, $3$D placement of UAVs, and user association matrices.
Energy-Efficient Precoding and Feeder-Link-Beam Matching Design for Bent-Pipe SATCOM Systems
This paper proposes a joint optimization framework for energy-efficient linear precoding and feeder-link-beam matching design in a multi-gateway multi-beam bent-pipe satellite communication system.
Multi-Objective Optimization for 3D Placement and Resource Allocation in OFDMA-based Multi-UAV Networks
The main aim of this work is to derive the optimal allocation of radio resources, 3D placement of UAVs, and user association matrices.
Two-tier User Association and Resource Allocation Design for Integrated Satellite-Terrestrial Networks
This paper presents a study of an integrated satellite-terrestrial network, where Low-Earth-Orbit (LEO) satellites are used to provide the backhaul link between base stations (BSs) and the core network.
Large-Scale Beam Placement and Resource Allocation Design for MEO-Constellation SATCOM
This paper presents a centralized framework for optimizing the joint design of beam placement, power, and bandwidth allocation in an MEO satellite constellation to fulfill the heterogeneous traffic demands of a large number of global users.
Energy-Efficient RIS-Enabled NOMA Communication for 6G LEO Satellite Networks
The proposed framework simultaneously optimizes the transmit power of ground terminals at LEO satellite and passive beamforming at RIS while ensuring the quality of services.
Near-Field Terahertz Communications: Model-Based and Model-Free Channel Estimation
Unlike prior works which mostly ignore the impact of near-field beam-split (NB) and consider either narrowband scenario or far-field models, this paper introduces both a model-based and a model-free techniques for wideband THz channel estimation in the presence of NB.
Network-Aided Intelligent Traffic Steering in 6G O-RAN: A Multi-Layer Optimization Framework
To enable an intelligent, programmable and multi-vendor radio access network (RAN) for 6G networks, considerable efforts have been made in standardization and development of open RAN (O-RAN).
BSA-OMP: Beam-Split-Aware Orthogonal Matching Pursuit for THz Channel Estimation
Terahertz (THz)-band has been envisioned for the sixth generation wireless networks thanks to its ultra-wide bandwidth and very narrow beamwidth.
Localization as a key enabler of 6G wireless systems: A comprehensive survey and an outlook
Finally, insights that arise from the presented analysis are summarized and used to highlight the most important future directions for localization in 6G wireless systems.
NBA-OMP: Near-field Beam-Split-Aware Orthogonal Matching Pursuit for Wideband THz Channel Estimation
The sixth-generation networks envision the terahertz (THz) band as one of the key enabling technologies because of its ultrawide bandwidth.
LEO-to-User Assignment and Resource Allocation for Uplink Transmit Power Minimization
This paper aims to develop satellite-user association and resource allocation mechanisms to minimize the total transmit power for integrated terrestrial and non-terrestrial networks wherein a constellation of LEO satellites provides the radio access services to both terrestrial base stations (BSs) and the satellite-enabled users (SUEs).
Edge Computing for Semantic Communication Enabled Metaverse: An Incentive Mechanism Design
Fourth, we present the design of the DL-based auction for edge resource allocation in SemCom-enabled Metaverse.
Joint Linear Precoding and DFT Beamforming Design for Massive MIMO Satellite Communication
This paper jointly designs linear precoding (LP) and codebook-based beamforming implemented in a satellite with massive multiple-input multiple-output (mMIMO) antenna technology.
Characterizing and Utilizing the Interplay between Quantum Technologies and Non-Terrestrial Networks
Quantum technologies are increasingly recognized as groundbreaking advancements set to redefine the landscape of computing, communications, and sensing by leveraging quantum phenomena, like entanglement and teleportation.
Intelligent Traffic Steering in Beyond 5G Open RAN based on LSTM Traffic Prediction
For this purpose, we propose a joint intelligent traffic prediction, flow-split distribution, dynamic user association and radio resource management (JIFDR) framework in the presence of unknown dynamic traffic demands.
Intelligent and Secure Radio Environments for 6G Vehicular Aided HetNets: Key Opportunities and Challenges
We present an overview of enabling technologies for ISRE-based 6G vehicular aided HetNets.
Opportunities for Intelligent Reflecting Surfaces in 6G-Empowered V2X Communications
This paper first describes the introduction of 6G-empowered V2X communications and IRS technology.
Grant-Free NOMA-OTFS Paradigm: Enabling Efficient Ubiquitous Access for LEO Satellite Internet-of-Things
With the blooming of Internet-of-Things (IoT), we are witnessing an explosion in the number of IoT terminals, triggering an unprecedented demand for ubiquitous wireless access globally.
An Overview of Channel Models for NGSO Satellites
Satellite communications industry is currently going through a rapid and profound transformation to adapt to the recent innovations and developments in the realm of non-geostationary orbit (NGSO) satellites.
GEO Payload Power Minimization: Joint Precoding and Beam Hopping Design
Regarding constraint on the maximum number of illuminated beams per time slot, the technical requirement is formulated as a sparse optimization problem in which the hardware-related beam illumination energy is modeled in a sparsity form of the LP vectors.
Terahertz-Band Channel and Beam Split Estimation via Array Perturbation Model
For the demonstration of ultra-wideband bandwidth and pencil-beamforming, the terahertz (THz)-band has been envisioned as one of the key enabling technologies for the sixth generation networks.
Rate Splitting Multiple Access for Cognitive Radio GEO-LEO Co-Existing Satellite Networks
We also propose two suboptimal schemes with fixed power allocation and random subcarrier beam assignment as the benchmark.
Terahertz-Band Integrated Sensing and Communications: Challenges and Opportunities
The sixth generation (6G) wireless networks aim to achieve ultra-high data transmission rates, very low latency and enhanced energy-efficiency.
Federated Multi-Task Learning for THz Wideband Channel and DoA Estimation
This paper addresses two major challenges in terahertz (THz) channel estimation: the beam-split phenomenon, i. e., beam misalignment because of frequency-independent analog beamformers, and computational complexity because of the usage of ultra-massive number of antennas to compensate propagation losses.
Implicit Channel Learning for Machine Learning Applications in 6G Wireless Networks
Without channel estimation, the proposed approach exhibits approximately 60% improvement in image and speech classification tasks for diverse scenarios such as millimeter wave and IEEE 802. 11p vehicular channels.
Joint Beam Hopping and Carrier Aggregation in High Throughput Multi-Beam Satellite Systems
Beam hopping (BH) and carrier aggregation (CA) are two promising technologies for the next generation satellite communication systems to achieve several orders of magnitude increase in system capacity and to significantly improve the spectral efficiency.
Deep Learning-Based Device-Free Localization in Wireless Sensor Networks
Location-based services (LBS) are witnessing a rise in popularity owing to their key features of delivering powerful and personalized digital experiences.
The Rise of Intelligent Reflecting Surfaces in Integrated Sensing and Communications Paradigms
The intelligent reflecting surface (IRS) alters the behavior of wireless media and, consequently, has potential to improve the performance and reliability of wireless systems such as communications and radar remote sensing.
Opportunities for Physical Layer Security in UAV Communication Enhanced with Intelligent Reflective Surfaces
Unmanned Aerial Vehicles (UAVs) are an important component of next-generation wireless networks that can assist in high data rate communications and provide enhanced coverage. Their high mobility and aerial nature offer deployment flexibility and low-cost infrastructure support to existing cellular networks and provide many applications that rely on mobile wireless communications.
Architectures and Synchronization Techniques for Distributed Satellite Systems: A Survey
This article also provides an extensive list of applications and examples of synchronization techniques for DSS in addition to the most significant advances in other operations closely related to synchronization, such as inter-satellite ranging and relative position.
Energy Efficiency Optimization for Backscatter Enhanced NOMA Cooperative V2X Communications under Imperfect CSI
Automotive-Industry 5. 0 will use beyond fifth-generation (B5G) technologies to provide robust, computationally intelligent, and energy-efficient data sharing among various onboard sensors, vehicles, and other devices.
Backscatter-Aided NOMA V2X Communication under Channel Estimation Errors
Then the RSUs transmit the superimposed signal to their serving vehicles in the second time slot exploiting decode and forward protocol.
When RIS Meets GEO Satellite Communications: A New Sustainable Optimization Framework in 6G
To enhance the effective gain, the signal delivery from satellite to the ground mobile terminal is also assisted by RIS which smartly shift the phase of the signal towards ground terminal.
THz-Empowered UAVs in 6G: Opportunities, Challenges, and Trade-Offs
Envisioned use cases of unmanned aerial vehicles (UAVs) impose new service requirements in terms of data rate, latency, and sensing accuracy, to name a few.
Multi-layer Space Information Networks: Access Design and Softwarization
Specifically, space-based Internet providers, such as Starlink, OneWeb, and SES O3b, can be utilized for broadband connectivity directly to/from the nanosatellites, which allows a larger degree of connectivity in space network topologies.
Adapting to Dynamic LEO-B5G Systems: Meta-Critic Learning Based Efficient Resource Scheduling
Low earth orbit (LEO) satellite-assisted communications have been considered as one of key elements in beyond 5G systems to provide wide coverage and cost-efficient data services.
Integration of Backscatter Communication with Multi-cell NOMA: A Spectral Efficiency Optimization under Imperfect SIC
This paper proposes a new optimization approach to enhance the spectral efficiency of nonorthogonal multiple access (NOMA)-BC network.
Frequency-packed Faster-than-Nyquist Signaling via Symbol-level Precoding for Multi-user MISO Redundant Transmissions
This work addresses the issue of interference generated by co-channel users in downlink multi-antenna multicarrier systems with frequency-packed faster-than-Nyquist (FTN) signaling.
A Survey on Non-Geostationary Satellite Systems: The Communication Perspective
The next phase of satellite technology is being characterized by a new evolution in non-geostationary orbit (NGSO) satellites, which conveys exciting new communication capabilities to provide non-terrestrial connectivity solutions and to support a wide range of digital technologies from various industries.
FedFog: Network-Aware Optimization of Federated Learning over Wireless Fog-Cloud Systems
data, users' heterogeneity), we first propose an efficient FL algorithm based on Federated Averaging (called FedFog) to perform the local aggregation of gradient parameters at fog servers and global training update at the cloud.
LEO Satellite Constellations for 5G and Beyond: How Will They Reshape Vertical Domains?
The rapid development of communication technologies in the past decades has provided immense vertical opportunities for individuals and enterprises.
A Hybrid Architecture for Federated and Centralized Learning
To address this common scenario, we propose a more efficient approach called hybrid federated and centralized learning (HFCL), wherein only the clients with sufficient resources employ FL, while the remaining ones send their datasets to the PS, which computes the model on behalf of them.
Hybrid Relay-Reflecting Intelligent Surface-Aided Wireless Communications: Opportunities, Challenges, and Future Perspectives
In this paper, we provide an overview of a hybrid relay-reflecting intelligent surface (HR-RIS) architecture, in which only a few elements are active and connected to power amplifiers and radio frequency chains.
Terahertz-Band Joint Ultra-Massive MIMO Radar-Communications: Model-Based and Model-Free Hybrid Beamforming
Wireless communications and sensing at terahertz (THz) band are increasingly investigated as promising short-range technologies because of the availability of high operational bandwidth at THz.
Federated Learning for Physical Layer Design
Model-free techniques, such as machine learning (ML), have recently attracted much interest towards the physical layer design, e. g., symbol detection, channel estimation, and beamforming.
Coverage Probability of Distributed IRS Systems Under Spatially Correlated Channels
This paper suggests the use of multiple distributed intelligent reflecting surfaces (IRSs) towards a smarter control of the propagation environment.
Information Theory Information Theory
NB-IoT Random Access for Non-Terrestrial Networks
The satellite component is recognized as a promising solution to complement and extend the coverage of future Internet of things (IoT) terrestrial networks (TNs).
Broadband Non-Geostationary Satellite Communication Systems: Research Challenges and Key Opportunities
Besides conventional geostationary (GSO) satellite broadband communication services, non-geostationary (NGSO) satellites are envisioned to support various new communication use cases from countless industries.
Machine Learning-Enabled Joint Antenna Selection and Precoding Design: From Offline Complexity to Online Performance
We investigate the performance of multi-user multiple-antenna downlink systems in which a BS serves multiple users via a shared wireless medium.
Information Theory Information Theory
Secure Vehicular Communications through Reconfigurable Intelligent Surfaces
Reconfigurable intelligent surfaces (RIS) is considered as a revolutionary technique to improve the wireless system performance by reconfiguring the radio wave propagation environment artificially.
A Remote Carrier Synchronization Technique for Coherent Distributed Remote Sensing Systems
Phase, frequency, and time synchronization are crucial requirements for many applications, such as multi-static remote sensing and communication systems.
Reconfigurable Intelligent Surface Optimal Placement in Millimeter-Wave Networks
Subsequently, based on the model we derive the end-to-end expression of the received signal power and, furthermore, provide approximate closed-form expressions in the case that the RIS size is either much smaller or at least equal to the transmission beam footprint.
Information Theory Signal Processing Information Theory
Learning-Assisted User Clustering in Cell-Free Massive MIMO-NOMA Networks
To address this problem, we develop two efficient unsupervised machine learning (ML) based UC algorithms, namely k-means++ and improved k-means++, to effectively cluster users into disjoint clusters in cell-free massive multiple-input multiple-output (CFmMIMO) system.
Reconfigurable Intelligent Surfaces in Challenging Environments: Underwater, Underground, Industrial and Disaster
Challenging environments comprise a range of scenarios, which share the fact that it is extremely difficult to establish a communication link using conventional technology due to many impairments typically associated with the propagation medium and increased signal scattering.
Multi-Antenna Data-Driven Eavesdropping Attacks and Symbol-Level Precoding Countermeasures
In this work, we consider secure communications in wireless multi-user (MU) multiple-input single-output (MISO) systems with channel coding in the presence of a multi-antenna eavesdropper (Eve).
Precoding for Satellite Communications: Why, How and What next?
Precoding has stood out as a promising multi-user transmission technique to meet the emerging throughput demand of satellite communication systems while awaiting the technological maturity for exploiting higher bands.
System Modelling and Design Aspects of Next Generation High Throughput Satellites
Future generation wireless networks are targeting the convergence of fixed, mobile and broadcasting systems with the integration of satellite and terrestrial systems towards utilizing their mutual benefits.
Reconfigurable Intelligent Surfaces for Smart Cities: Research Challenges and Opportunities
The concept of Smart Cities has been introduced as a way to benefit from the digitization of various ecosystems at a city level.
Short-Packet Communications for MIMO NOMA Systems over Nakagami-m Fading: BLER and Minimum Blocklength Analysis
The achieved results show that MIMO NOMA can serve multiple users simultaneously using a smaller blocklength compared with MIMO OMA, thus demonstrating the benefits of MIMO NOMA for SPC in minimizing the transmission latency.
Downlink Transmit Design for Massive MIMO LEO Satellite Communications
We show that, in this case, the design of precoding vectors can be simplified into that of scalar variables, for which an effective algorithm is developed.
UAV Relay-Assisted Emergency Communications in IoT Networks: Resource Allocation and Trajectory Optimization
In this context, we aim to maximize the number of served IoT devices by jointly optimizing bandwidth, power allocation, and the UAV trajectory while satisfying each device's requirement and the UAV's limited storage capacity.
Traffic Simulator for Multibeam Satellite Communication Systems
This paper aims at developing a tool, multibeam satellite traffic simulator, that helps addressing these fundamental challenges, and more importantly, provides an understanding to the spatial-temporal traffic pattern of satellite networks in large-scale environments.
A Novel Heap-based Pilot Assignment for Full Duplex Cell-Free Massive MIMO with Zero-Forcing
This paper investigates the combined benefits of full-duplex (FD) and cell-free massive multiple-input multipleoutput (CF-mMIMO), where a large number of distributed access points (APs) having FD capability simultaneously serve numerous uplink and downlink user equipments (UEs) on the same time-frequency resources.
Energy Minimization in UAV-Aided Networks: Actor-Critic Learning for Constrained Scheduling Optimization
The conventional RL/DRL, e. g., deep Q-learning, however, is limited in dealing with two main issues in constrained combinatorial optimization, i. e., exponentially increasing action space and infeasible actions.
Joint Forecasting and Interpolation of Graph Signals Using Deep Learning
We tackle the problem of forecasting network-signal snapshots using past signal measurements acquired by a subset of network nodes.
Task-Oriented Data Compression for Multi-Agent Communications Over Bit-Budgeted Channels
Motivated by these recent developments, in this paper, we perform an indirect design of the communications in a multi-agent system (MAS) in which agents cooperate to maximize the averaged sum of discounted one-stage rewards of a collaborative task.
Joint User Grouping, Scheduling, and Precoding for Multicast Energy Efficiency in Multigroup Multicast Systems
This paper studies the joint design of user grouping, scheduling (or admission control) and precoding to optimize energy efficiency (EE) for multigroup multicast scenarios in single-cell multiuser MISO downlink channels.
ProxSGD: Training Structured Neural Networks under Regularization and Constraints
In this paper, we consider the problem of training neural networks (NN).
Federated Learning Meets Contract Theory: Energy-Efficient Framework for Electric Vehicle Networks
In this paper, we propose a novel energy-efficient framework for an electric vehicle (EV) network using a contract theoretic-based economic model to maximize the profits of charging stations (CSs) and improve the social welfare of the network.
Networking and Internet Architecture Signal Processing
Learning-Based Physical Layer Communications for Multi-agent Collaboration
In this work, it is demonstrated that the performance of the collaborative task can be improved if the agents learn jointly how to communicate and to act, even in the presence of a delay in the communication channel.
Information Theory Multiagent Systems Information Theory
Successive Convex Approximation Algorithms for Sparse Signal Estimation with Nonconvex Regularizations
The proposed framework has several attractive features, namely, i) flexibility, as different choices of the approximate function lead to different type of algorithms; ii) fast convergence, as the problem structure can be better exploited by a proper choice of the approximate function and the stepsize is calculated by the line search; iii) low complexity, as the approximate function is convex and the line search scheme is carried out over a differentiable function; iv) guaranteed convergence to a stationary point.
Constrained Bayesian Active Learning of Interference Channels in Cognitive Radio Networks
The cognitive part of this sequential probing process is the selection of the power levels of the Secondary Users (SUs) which aims to learn the PU interference constraint with a minimum number of probing attempts while setting a limit on the number of harmful probing-induced interference events or equivalently of NACK packet observations over a time window.
