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Found 67 papers, 3 papers with code
A Doubly-Dispersive MIMO Channel Model Parametrized with Stacked Intelligent Metasurfaces
Introduced with the advent of statistical wireless channel models for high mobility communications and having a profound role in communication-centric (CC) integrated sensing and communications (ISAC), the doubly-dispersive (DD) channel structure has long been heralded as a useful tool enabling the capture of the most important fading effects undergone by an arbitrary time-domain transmit signal propagating through some medium.
Holographic Metasurfaces Enabling Wave Computing for 6G: Status Overview, Challenges, and Future Research Trends
Recent advancements in wave computing using metasurfaces are poised to transform wireless communications by enabling high-speed, energy-efficient, and highly parallelized signal processing.
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.
Circuit-Compliant Optimization of Dynamic Metasurface Antennas for Near-Field Localization
This paper presents an optimization framework for near-field localization with Dynamic Metasurface Antenna (DMA) receivers.
On the Detection of Non-Cooperative RISs: Scan B-Testing via Deep Support Vector Data Description
In this paper, we study the problem of promptly detecting the presence of non-cooperative activity from one or more Reconfigurable Intelligent Surfaces (RISs) with unknown characteristics lying in the vicinity of a Multiple-Input Multiple-Output (MIMO) communication system using Orthogonal Frequency-Division Multiplexing (OFDM) transmissions.
Simultaneous Communications and Sensing with Hybrid Reconfigurable Intelligent Surfaces
Hybrid Reconfigurable Intelligent Surfaces (HRISs) constitute a new paradigm of truly smart metasurfaces with the additional features of signal reception and processing, which have been primarily considered for channel estimation and self-reconfiguration.
Optimal One- and Two-Sided Multi-level ASK Modulation or RIS-Assisted Noncoherent Communication Systems
We also present a novel optimization framework to obtain the optimal one- and two-sided ASK modulation schemes that minimize the SEP under constraints on the available average transmit power for both the blocked and unblocked direct channel scenarios.
Near-Field Multipath MIMO Channel Model for Imperfect Surface Reflection
Near-field (NF) communications is receiving renewed attention in the context of passive reconfigurable intelligent surfaces (RISs) due to their potentially extremely large dimensions.
Fast Network Recovery from Large-Scale Disasters: A Resilient and Self-Organizing RAN Framework
Extreme natural phenomena are occurring more frequently everyday in the world, challenging, among others, the infrastructure of communication networks.
Near-Field Localization with Antenna Arrays in the Presence of Direction-Dependent Mutual Coupling
In this paper, we devise a low complexity one-dimensional (1D) iterative method based on an oblique projection operator (IMOP) that estimates direction-dependent MC and the locations of multiple near-field sources.
Simultaneous Near-Field THz Communications and Sensing with Full Duplex Metasurface Transceivers
In this paper, a Full Duplex (FD) eXtremely Large (XL) Multiple-Input Multiple-Output (MIMO) node equipped with reconfigurable metasurface antennas at its transmission and reception sides is considered, which is optimized for simultaneous multi-user communications and sensing in the near-field regime at THz frequencies.
Asymptotically Optimal Closed-Form Phase Configuration of $1$-bit RISs via Sign Alignment
While Reconfigurable Intelligent Surfaces (RISs) constitute one of the most prominent enablers for the upcoming sixth Generation (6G) of wireless networks, the design of efficient RIS phase profiles remains a notorious challenge when large numbers of phase-quantized unit cells are involved, typically of a single bit, as implemented by a vast majority of existing metasurface prototypes.
Single- and Multi-Agent Private Active Sensing: A Deep Neuroevolution Approach
In this paper, we focus on one centralized and one decentralized problem of active hypothesis testing in the presence of an eavesdropper.
Near-Field Channel Modeling for Holographic MIMO Communications
Empowered by the latest progress on innovative metamaterials/metasurfaces and advanced antenna technologies, holographic multiple-input multiple-output (H-MIMO) emerges as a promising technology to fulfill the extreme goals of the sixth-generation (6G) wireless networks.
Distributed Intelligent Integrated Sensing and Communications: The 6G-DISAC Approach
This paper introduces the concept of Distributed Intelligent integrated Sensing and Communications (DISAC), which expands the capabilities of Integrated Sensing and Communications (ISAC) towards distributed architectures.
Towards Distributed and Intelligent Integrated Sensing and Communications for 6G Networks
This paper introduces the distributed and intelligent integrated sensing and communications (DISAC) concept, a transformative approach for 6G wireless networks that extends the emerging concept of integrated sensing and communications (ISAC).
DRL-Based Orchestration of Multi-User MISO Systems with Stacked Intelligent Metasurfaces
Stacked intelligent metasurfaces (SIM) represents an advanced signal processing paradigm that enables over-the-air processing of electromagnetic waves at the speed of light.
$1$-Bit SubTHz RIS with Planar Tightly Coupled Dipoles: Beam Shaping and Prototypes
In this paper, a proof-of-concept study of a $1$-bit wideband reconfigurable intelligent surface (RIS) comprising planar tightly coupled dipoles (PTCD) is presented.
RIS-Augmented Millimeter-Wave MIMO Systems for Passive Drone Detection
In the past decade, the number of amateur drones is increasing, and this trend is expected to continue in the future.
Multi-Agent Reinforcement Learning for Offloading Cellular Communications with Cooperating UAVs
Effective solutions for intelligent data collection in terrestrial cellular networks are crucial, especially in the context of Internet of Things applications.
Far- versus Near-Field RIS Modeling and Beam Design
In this chapter, we investigate the mathematical foundation of the modeling and design of reconfigurable intelligent surfaces (RIS) in both the far- and near-field regimes.
Metasurface-Based Receivers with $1$-bit ADCs for Multi-User Uplink Communications
The massive Multiple-Input Multiple-Output (mMIMO) concept has been recently moving forward to extreme scales to address the envisioned requirements of next generation networks.
Jointly Optimal RIS Placement and Power Allocation for Underlay D2D Communications: An Outage Probability Minimization Approach
In the transformed problem, an expression for the average value of the signal-to-interference-noise ratio (SINR) at the D2D receiver is derived in closed-form.
Multi-Target Two-way Integrated Sensing and Communications with Full Duplex MIMO Radios
In this paper, we propose a multiple input multiple output (MIMO) Full-Duplex Integrated Sensing and Communication System consisting of multiple targets, a single downlink, and a single uplink user.
Wideband THz Multi-User Downlink Communications with Leaky Wave Antennas
Extremely massive multiple-input multiple-output (MIMO) antennas can be costly and power inefficient for wideband THz communications.
RIS Position and Orientation Estimation via Multi-Carrier Transmissions and Multiple Receivers
In this paper, we consider a static user equipped with an RIS and study the RIS localization problem (i. e., joint three-dimensional position and orientation estimation), when operating in a system comprising a single-antenna transmitter and multiple synchronized single-antenna receivers with known locations.
Autoregressive Attention Neural Networks for Non-Line-of-Sight User Tracking with Dynamic Metasurface Antennas
User localization and tracking in the upcoming generation of wireless networks have the potential to be revolutionized by technologies such as the Dynamic Metasurface Antennas (DMAs).
Lyapunov-Driven Deep Reinforcement Learning for Edge Inference Empowered by Reconfigurable Intelligent Surfaces
In this paper, we propose a novel algorithm for energy-efficient, low-latency, accurate inference at the wireless edge, in the context of 6G networks endowed with reconfigurable intelligent surfaces (RISs).
Performance of RIS-Aided Nearfield Localization under Beams Approximation from Real Hardware Characterization
The technology of reconfigurable intelligent surfaces (RIS) has been showing promising potential in a variety of applications relying on Beyond-5G networks.
Robust Millimeter Beamforming via Self-Supervised Hybrid Deep Learning
Beamforming with large-scale antenna arrays has been widely used in recent years, which is acknowledged as an important part in 5G and incoming 6G.
STAR-RIS-Enabled Simultaneous Indoor and Outdoor 3D Localization: Theoretical Analysis and Algorithmic Design
Recent research and development interests deal with metasurfaces for wireless systems beyond their consideration as intelligent tunable reflectors.
RISs and Sidelink Communications in Smart Cities: The Key to Seamless Localization and Sensing
A smart city involves, among other elements, intelligent transportation, crowd monitoring, and digital twins, each of which requires information exchange via wireless communication links and localization of connected devices and passive objects (including people).
RIS-Aided Monostatic Sensing and Object Detection with Single and Double Bounce Multipath
We propose a framework for monostatic sensing by a user equipment (UE), aided by a reconfigurable intelligent surface (RIS) in environments with single- and double-bounce signal propagation.
RIS-Enabled and Access-Point-Free Simultaneous Radio Localization and Mapping
In the upcoming sixth generation (6G) of wireless communication systems, reconfigurable intelligent surfaces~(RISs) are regarded as one of the promising technological enablers, which can provide programmable signal propagation.
3D Localization with a Single Partially-Connected Receiving RIS: Positioning Error Analysis and Algorithmic Design
We particularly focus on the scenarios where the user is located in the far-field of all the R-RIS subarrays, and present a three-Dimensional (3D) localization method which is based on narrowband signaling and Angle of Arrival (AoA) estimates of the impinging signals at each single-receive-RF R-RIS subarray.
Holographic MIMO Communications: Theoretical Foundations, Enabling Technologies, and Future Directions
In this survey, we present a comprehensive overview of the latest advances in the HMIMO communications paradigm, with a special focus on their physical aspects, their theoretical foundations, as well as the enabling technologies for HMIMO systems.
Integrated Sensing and Communications with Reconfigurable Intelligent Surfaces
Integrated sensing and communications (ISAC) are envisioned to be an integral part of future wireless networks, especially when operating at the millimeter-wave (mmWave) and terahertz (THz) frequency bands.
Joint Channel and Direction Estimation for Ground-to-UAV Communications Enabled by A Simultaneous Reflecting and Sensing RIS
Hybrid Reconfigurable Intelligent Surfaces (HRISs), which are capable of simultaneous programmable reflections and sensing, are expected to play a significant role in future wireless networks, enabling various Integrated Sensing and Communication (ISAC) applications.
Compressed-Sensing-Based 3D Localization with Distributed Passive Reconfigurable Intelligent Surfaces
In this paper, the programmable signal propagation paradigm, enabled by Reconfigurable Intelligent Surfaces (RISs), is exploited for high accuracy $3$-Dimensional (3D) user localization with a single multi-antenna base station.
Joint User Localization and Location Calibration of A Hybrid Reconfigurable Intelligent Surface
The recent research in the emerging technology of reconfigurable intelligent surfaces (RISs) has identified its high potential for localization and sensing.
Reconfigurable Intelligent Computational Surfaces: When Wave Propagation Control Meets Computing
The envisioned sixth-generation (6G) of wireless networks will involve an intelligent integration of communications and computing, thereby meeting the urgent demands of diverse applications.
Simultaneous Indoor and Outdoor 3D Localization with STAR-RIS-Assisted Millimeter Wave Systems
Simultaneously transmitting (refracting) and reflecting reconfigurable intelligent surfaces (STAR-RISs) have been recently identified to improve the spectrum/energy efficiency and extend the communication range.
Pervasive Machine Learning for Smart Radio Environments Enabled by Reconfigurable Intelligent Surfaces
The emerging technology of Reconfigurable Intelligent Surfaces (RISs) is provisioned as an enabler of smart wireless environments, offering a highly scalable, low-cost, hardware-efficient, and almost energy-neutral solution for dynamic control of the propagation of electromagnetic signals over the wireless medium, ultimately providing increased environmental intelligence for diverse operation objectives.
Differential Data-Aided Beam Training for RIS-Empowered Multi-Antenna Communications
In this paper, a zero overhead beam training for RIS is proposed, relying on data transmission and reception based on non-CDS (NCDS).
Leveraging RIS-Enabled Smart Signal Propagation for Solving Infeasible Localization Problems
Reconfigurable intelligent surfaces (RISs) have tremendous potential for both communication and localization.
Arbitrary Beam Pattern Approximation via RISs with Measured Element Responses
Smart radio environments (SREs) are seen as a key rising concept of next generation wireless networks, where propagation channels between transmitters and receivers are purposely controlled.
RIS-Enabled Self-Localization: Leveraging Controllable Reflections With Zero Access Points
In this paper, we introduce a novel use-case of the RIS technology in radio localization, which is enabling the user to estimate its own position via transmitting orthogonal frequency-division multiplexing (OFDM) pilots and processing the signal reflected from the RIS.
Jointly Learned Symbol Detection and Signal Reflection in RIS-Aided Multi-user MIMO Systems
Reconfigurable Intelligent Surfaces (RISs) are regarded as a key technology for future wireless communications, enabling programmable radio propagation environments.
Channel Estimation with Simultaneous Reflecting and Sensing Reconfigurable Intelligent Metasurfaces
As an indicative application of HRISs, we formulate and solve the individual channels identification problem for the uplink of multi-user HRIS-empowered systems.
Non-Coherent MIMO-OFDM Uplink empowered by the Spatial Diversity in Reflecting Surfaces
As a benchmark, analytical expressions for the Signal-to-Interference and Noise Ratio (SINR) of the proposed system are presented.
DDU-Net: Dual-Decoder-U-Net for Road Extraction Using High-Resolution Remote Sensing Images
Extracting roads from high-resolution remote sensing images (HRSIs) is vital in a wide variety of applications, such as autonomous driving, path planning, and road navigation.
A New RIS Architecture with a Single Power Amplifier: Energy Efficiency and Error Performance Analysis
Reconfigurable intelligent surface (RIS)-assisted communication have recently attracted the attention of the wireless communication community as a potential candidate for the next $6$-th generation (6G) of wireless networks.
ADMM-DAD net: a deep unfolding network for analysis compressed sensing
In this paper, we propose a new deep unfolding neural network based on the ADMM algorithm for analysis Compressed Sensing.
Non-Coherent Modulation for RIS-Empowered Multi-Antenna OFDM Communications
The Reconfigurable Intelligent Surface (RIS) constitutes one of the prominent technologies for the next 6-th Generation (6G) of wireless communications.
Information Theory Information Theory
Self-Calibrating Indoor Localization with Crowdsourcing Fingerprints and Transfer Learning
Precise indoor localization is one of the key requirements for fifth Generation (5G) and beyond, concerning various wireless communication systems, whose applications span different vertical sectors.
Multi-hop RIS-Empowered Terahertz Communications: A DRL-based Hybrid Beamforming Design
We investigate the joint design of digital beamforming matrix at the BS and analog beamforming matrices at the RISs, by leveraging the recent advances in deep reinforcement learning (DRL) to combat the propagation loss.
Uplink Beam Management for Millimeter Wave Cellular MIMO Systems with Hybrid Beamforming
Hybrid analog and digital BeamForming (HBF) is one of the enabling transceiver technologies for millimeter Wave (mmWave) Multiple Input Multiple Output (MIMO) systems.
Information Theory Information Theory
Near-field Localization with a Reconfigurable Intelligent Surface Acting as Lens
Exploiting wavefront curvature enables localization with limited infrastructure and hardware complexity.
Signal Processing Information Theory Information Theory
Phase Configuration Learning in Wireless Networks with Multiple Reconfigurable Intelligent Surfaces
Reconfigurable Intelligent Surfaces (RISs) are recently gaining remarkable attention as a low-cost, hardware-efficient, and highly scalable technology capable of offering dynamic control of electro-magnetic wave propagation.
Hybrid Beamforming for RIS-Empowered Multi-hop Terahertz Communications: A DRL-based Method
Wireless communication in the TeraHertz band (0. 1--10 THz) is envisioned as one of the key enabling technologies for the future six generation (6G) wireless communication systems.
Channel Estimation for RIS-Empowered Multi-User MISO Wireless Communications
We also discuss the downlink achievable sum rate computation with estimated channels and different precoding schemes for the base station.
Reconfigurable Intelligent Surfaces and Metamaterials: The Potential of Wave Propagation Control for 6G Wireless Communications
Motivated by the late research excitement on the RIS potential for intelligent EM wave propagation modulation, we describe the status on RIS hardware architectures and present key open challenges and future research directions for RIS design and RIS-empowered 6G wireless communications.
Dynamic Metasurface Antennas for 6G Extreme Massive MIMO Communications
Next generation wireless base stations and access points will transmit and receive using extremely massive numbers of antennas.
Holographic MIMO Surfaces for 6G Wireless Networks: Opportunities, Challenges, and Trends
Future wireless networks are expected to evolve towards an intelligent and software reconfigurable paradigm enabling ubiquitous communications between humans and mobile devices.
Indoor Signal Focusing with Deep Learning Designed Reconfigurable Intelligent Surfaces
Reconfigurable Intelligent Surfaces (RISs) comprised of tunable unit elements have been recently considered in indoor communication environments for focusing signal reflections to intended user locations.
Deep Learning for UL/DL Channel Calibration in Generic Massive MIMO Systems
We then leverage the trained deep neural network with the instantaneously estimated UL channel to calibrate the DL one, which is not observable during the UL transmission phase.
