242 citations · 365 across the 28 of their papers we have counts for
32 papers
Flexible Intelligent Metasurface for Downlink Communications under Statistical CSI
Vaibhav Kumar, Anastasios Papazafeiropoulos, Pandelis Kourtessis +4
Flexible intelligent metasurface (FIM) is a recently developed, groundbreaking hardware technology with promising potential for 6G wireless systems. Unlike conventional rigid anten…
Visual Event Detection over AI-Edge LEO Satellites with AoI Awareness
Chathuranga M. Wijerathna Basnayaka, Haeyoung Lee, Pandelis Kourtessis +5
Non terrestrial networks (NTNs), particularly low Earth orbit (LEO) satellite systems, play a vital role in supporting future mission critical applications such as disaster relief.…
Ergodic Mutual Information and Outage Probability for SIM-Assisted Holographic MIMO Communications
Anastasios Papazafeiropoulos, Pandelis Kourtessis, Dimitra I. Kaklamani +1
Stacked intelligent metasurface (SIM) is a promising enabler for next-generation high-capacity networks that exhibit better performance compared to its single-layer counterpart by…
Channel Estimation for Stacked Intelligent Metasurfaces in Rician Fading Channels
Anastasios Papazafeiropoulos, Pandelis Kourtessis, Dimitra I. Kaklamani +1
The recent combination of the rising architectures, known as stacked intelligent metasurface (SIM) and holographic multiple-input multiple-output (HMIMO), drives toward breakthroug…
STARS-Enabled Full-Duplex Two-Way mMIMO System Under Spatially-Correlated Channels
Anastasios Papazafeiropoulos, Pandelis Kourtessis, Symeon Chatzinotas +2
\underline{S}imultaneous \underline{t}ransmitting \underline{a}nd \underline{r}eflecting \underline{s}urface (STARS)-assisted systems have emerged to fill this gap by providing $ 3…
Near-Field Beamforming for Stacked Intelligent Metasurfaces-assisted MIMO Networks
Anastasios Papazafeiropoulos, Pandelis Kourtessis, Symeon Chatzinotas +2
Stacked intelligent metasurfaces (SIMs) have recently gained significant interest since they enable precoding in the wave domain that comes with increased processing capability and…
Achievable Rate Optimization for Large Stacked Intelligent Metasurfaces Based on Statistical CSI
Anastasios Papazafeiropoulos, Pandelis Kourtessis, Symeon Chatzinotas +2
Stacked intelligent metasurface (SIM) is an emerging design that consists of multiple layers of metasurfaces. A SIM enables holographic multiple-input multiple-output (HMIMO) preco…
STAR-RIS-Assisted Communication Radar Coexistence: Analysis and Optimization
Anastasios Papazafeiropoulos, Pandelis Kourtessis, Symeon Chatzinotas
Integrated sensing and communication (ISAC) is expected to play a prominent role among emerging technologies in future wireless communications. In particular, a communication radar…
Two-Timescale Design for Active STAR-RIS Aided Massive MIMO Systems
Anastasios Papazafeiropoulos, Hanxiao Ge, Pandelis Kourtessis +3
Simultaneously transmitting and reflecting \textcolor{black}{reconfigurable intelligent surface} (STAR-RIS) is a promising implementation of RIS-assisted systems that enables full-…
Achievable Rate Optimization for Stacked Intelligent Metasurface-Assisted Holographic MIMO Communications
Anastasios Papazafeiropoulos, Jiancheng An, Pandelis Kourtessis +2
Stacked intelligent metasurfaces (SIM) is a revolutionary technology, which can outperform its single-layer counterparts by performing advanced signal processing relying on wave pr…
Performance of Double-Stacked Intelligent Metasurface-Assisted Multiuser Massive MIMO Communications in the Wave Domain
Anastasios Papazafeiropoulos, Pandelis Kourtessis, Symeon Chatzinotas +2
Although reconfigurable intelligent surface (RIS) is a promising technology for shaping the propagation environment, it consists of a single-layer structure within inherent limitat…
STAR-RIS Assisted Cell-Free Massive MIMO System Under Spatially-Correlated Channels
Anastasios Papazafeiropoulos, Hien Quoc Ngo, Pandelis Kourtessis +1
This paper investigates the performance of downlink simultaneous transmitting and reflecting reconfigurable intelligent surface (STAR-RIS)-assisted cell-free (CF) massive multiple-…
Max-Min SINR Analysis of STAR-RIS Assisted Massive MIMO Systems with Hardware Impairments
Anastasios Papazafeiropoulos, Pandelis Kourtessis, Symeon Chatzinotas
Reconfigurable intelligent surface (RIS) has emerged as a cost-effective solution to improve wireless communication performance through just passive reflection. Recently, the conce…
Cooperative RIS and STAR-RIS assisted mMIMO Communication: Analysis and Optimization
Anastasios Papazafeiropoulos, Ahmet M. Elbir, Pandelis Kourtessis +2
Reconfigurable intelligent surface (RIS) has emerged as a cost-effective and promising solution to extend the wireless signal coverage and improve the performance via passive signa…
Achievable Rate of a STAR-RIS Assisted Massive MIMO System Under Spatially-Correlated Channels
Anastasios Papazafeiropoulos, Le-Nam Tran, Zaid Abdullah +2
Reconfigurable intelligent surfaces (RIS)-assisted massive multiple-input multiple-output (mMIMO) is a promising technology for applications in next-generation networks. However, r…
Near-Field Terahertz Communications: Model-Based and Model-Free Channel Estimation
Ahmet M. Elbir, Wei Shi, Anastasios K. Papazafeiropoulos +2
Terahertz (THz) band is expected to be one of the key enabling technologies of the sixth generation (6G) wireless networks because of its abundant available bandwidth and very narr…
Impact of Channel Aging on Reconfigurable Intelligent Surface Aided Massive MIMO Systems with Statistical CSI
Anastasios Papazafeiropoulos, Ioannis Krikidis, Pandelis Kourtessis
The incorporation of reconfigurable intelligent surface (RIS) into massive multiple-input-multiple-output (mMIMO) systems can unleash the potential of next-generation networks by i…
Terahertz-Band Channel and Beam Split Estimation via Array Perturbation Model
Ahmet M. Elbir, Wei Shi, Anastasios K. Papazafeiropoulos +2
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 generat…
Joint Spatial Division and Multiplexing for FDD in Intelligent Reflecting Surface-assisted Massive MIMO Systems
Anastasios Papazafeiropoulos, Pandelis Kourtessis, Konstantinos Ntontin +1
Intelligent reflecting surface (IRS) is a promising technology to deliver the higher spectral and energy requirements in fifth-generation (5G) and beyond wireless networks while sh…
Coverage Probability of STAR-RIS assisted Massive MIMO systems with Correlation and Phase Errors
Anastasios Papazafeiropoulos, Zaid Abdullah, Pandelis Kourtessis +2
In this paper, we investigate a simultaneous transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) assisting a massive multiple-input multiple-output (mMIMO) sy…
Coverage Probability of Double-IRS Assisted Communication Systems
Anastasios Papazafeiropoulos, Pandelis Kourtessis, Symeon Chatzinotas +1
In this paper, we focus on the coverage probability of a double-intelligent reflecting surface (IRS) assisted wireless network and study the impact of multiplicative beamforming ga…
Scalable Cell-Free Massive MIMO Systems: Impact of Hardware Impairments
Anastasios Papazafeiropoulos, Emil Björnson, Pandelis Kourtessis +2
Standard cell-free (CF) multiple-input-multiple-output (mMIMO) systems is a promising technology to cover the demands for higher data rates in fifth-generation (5G) networks and be…
Asymptotic Analysis of Max-Min Weighted SINR for IRS-Assisted MISO Systems with Hardware Impairments
Anastasios Papazafeiropoulos, Cunhua Pan, Ahmet Elbir +3
We focus on the realistic maximization of the uplink minimum signal-to-interference-plus-noise ratio (SINR) of a general multiple-input single-output (MISO) system assisted by an i…
A Hybrid Architecture for Federated and Centralized Learning
Ahmet M. Elbir, Sinem Coleri, Anastasios K. Papazafeiropoulos +2
Many of the machine learning tasks rely on centralized learning (CL), which requires the transmission of local datasets from the clients to a parameter server (PS) entailing huge c…