no code implementations • 14 Apr 2025 • Pigi P. Papanikolaou, Dimitrios Bozanis, Sotiris A. Tegos, Panagiotis D. Diamantoulakis, George K. Karagiannidis
Security is emerging as a critical performance metric for next-generation wireless networks, but conventional multiple-input-multiple-output (MIMO) systems often suffer from severe path loss and are vulnerable to nearby eavesdroppers due to their fixed-antenna configurations.
no code implementations • 6 Apr 2025 • Yuquan Xiao, Qinghe Du, Wenchi Cheng, George K. Karagiannidis, Arumugam Nallanathan, Mohsen Guizani
Generative Artificial Intelligence (GenAI) is playing an increasingly important role in enriching and facilitating human life by generating various useful information, of which real-time GenAI is a significant part and has great potential in applications such as real-time robot control, automated driving, augmented reality, etc.
no code implementations • 21 Mar 2025 • Thrassos K. Oikonomou, Sotiris A. Tegos, Panagiotis D. Diamantoulakis, George K. Karagiannidis
We present a novel cross-band modulation framework that combines 3D modulation in the RF domain with intensity modulation and direct detection in the optical domain, the first such integration to enhance communication reliability.
no code implementations • 12 Mar 2025 • Harris K. Armeniakos, Petros S. Bithas, Sotiris A. Tegos, Athanasios G. Kanatas, George K. Karagiannidis
Stochastic geometry is the study and analysis of random spatial patterns, and as such, stochastic geometry tools have been considered for the performance evaluation of wireless networks with different types of nodes.
no code implementations • 24 Feb 2025 • Qihao Peng, Qu Luo, Zheng Chu, Zihuai Lin, Maged Elkashlan, Pei Xiao, George K. Karagiannidis, Christos Masouros
In this paper, we investigate a cell-free massive multiple-input and multiple-output (MIMO)-enabled integration communication, computation, and sensing (ICCS) system, aiming to minimize the maximum computation latency to guarantee the stringent sensing requirements.
no code implementations • 20 Feb 2025 • Fan Zhang, Zhaocheng Wang, Tianqi Mao, Tianyu Jiao, Yinxiao Zhuo, Miaowen Wen, Wei Xiang, Sheng Chen, George K. Karagiannidis
However, the unprecedented characteristics of 6G, especially the doubly dispersive channel, make classical ISAC waveforms rather challenging to guarantee a desirable performance level.
no code implementations • 20 Dec 2024 • Junteng Yao, Tuo Wu, Liaoshi Zhou, Ming Jin, Cunhua Pan, Maged Elkashlan, Fumiyuki Adachi, George K. Karagiannidis, Naofal Al-Dhahir, Chau Yuen
In this paper, we analyze the role of fluid antenna systems (FAS) in multi-user systems with hardware impairments (HIs).
no code implementations • 18 Dec 2024 • Nikos G. Evgenidis, Nikos A. Mitsiou, Sotiris A. Tegos, Panagiotis D. Diamantoulakis, George K. Karagiannidis
In this paper, we propose a novel approach to minimize the inference delay in semantic segmentation using split learning (SL), tailored to the needs of real-time computer vision (CV) applications for resource-constrained devices.
no code implementations • 5 Dec 2024 • Tuo Wu, Kangda Zhi, Junteng Yao, Xiazhi Lai, Jianchao Zheng, Hong Niu, Maged Elkashlan, Kai-Kit Wong, Chan-Byoung Chae, Zhiguo Ding, George K. Karagiannidis, Merouane Debbah, Chau Yuen
Fluid antenna system (FAS) as a new version of reconfigurable antenna technologies promoting shape and position flexibility, has emerged as an exciting and possibly transformative technology for wireless communications systems.
no code implementations • 13 Nov 2024 • Junteng Yao, Ming Jin, Tuo Wu, Maged Elkashlan, Chau Yuen, Kai-Kit Wong, George K. Karagiannidis, Hyundong Shin
Cognitive radio (CR) networks face significant challenges in spectrum sensing, especially under spectrum scarcity.
no code implementations • 2 Oct 2024 • Nikos G. Evgenidis, Nikos A. Mitsiou, Sotiris A. Tegos, Panagiotis D. Diamantoulakis, Panagiotis Sarigiannidis, Ioannis Krikidis, George K. Karagiannidis
Semantic communications are considered a promising beyond-Shannon/bit paradigm to reduce network traffic and increase reliability, thus making wireless networks more energy efficient, robust, and sustainable.
no code implementations • 5 Sep 2024 • Shunyu Li, Fan Zhang, Tianqi Mao, Rui Na, Zhaocheng Wang, George K. Karagiannidis
This paper proposes a transmit beamforming strategy for the integrated sensing and communication (ISAC) systems enabled by the novel stacked intelligent metasurface (SIM) architecture, where the base station (BS) simultaneously performs downlink communication and radar target detection via different beams.
no code implementations • 4 Jun 2024 • Yuquan Xiao, Qinghe Du, Wenchi Cheng, Panagiotis D. Diamantoulakis, George K. Karagiannidis
We then investigate how to find a compromise between average AoT and wireless transmission efficiency with limited resources.
no code implementations • 4 Jun 2024 • Yuquan Xiao, Qinghe Du, George K. Karagiannidis
Motivated by this concern, and following the spirit of entropic value-at-risk (EVaR) in the field of risk analysis, in this paper we present a concept, termed Statistical AoI, for providing a unified framework to guarantee various requirements of risk-sensitive status-update services with the demand on the violation probability of the peak age.
no code implementations • 31 May 2024 • Nikos G. Evgenidis, Nikos A. Mitsiou, Sotiris A. Tegos, Panagiotis D. Diamantoulakis, Panagiotis Sarigiannidis, Ioannis T. Rekanos, George K. Karagiannidis
To this end, we examine the theoretical mean squared error (MSE) for OTA transmission under time sampling error and ISI, while also exploring methods for minimizing the MSE in the OTA transmission.
no code implementations • 30 May 2024 • Minghui Wu, Zhen Gao, Zhaocheng Wang, Dusit Niyato, George K. Karagiannidis, Sheng Chen
Specifically, we propose a deep joint semantic coding and beamforming (JSCBF) scheme for airship-based massive MIMO image transmission network in space, in which semantics from both source and channel are fused to jointly design the semantic coding and physical layer beamforming.
no code implementations • 20 May 2024 • Pavlos S. Bouzinis, Panagiotis Radoglou-Grammatikis, Ioannis Makris, Thomas Lagkas, Vasileios Argyriou, Georgios Th. Papadopoulos, Panagiotis Sarigiannidis, George K. Karagiannidis
Federated learning (FL) is a decentralized learning technique that enables participating devices to collaboratively build a shared Machine Leaning (ML) or Deep Learning (DL) model without revealing their raw data to a third party.
1 code implementation • 25 Mar 2024 • Sulaiman Aburakhia, Abdallah Shami, George K. Karagiannidis
Despite many attempts in the existing literature to bridge this gap, most are limited to specific applications and focus mainly on feature extraction, often assuming extensive prior knowledge in signal processing.
no code implementations • 26 Feb 2024 • Nikos G. Evgenidis, Nikos A. Mitsiou, Vasiliki I. Koutsioumpa, Sotiris A. Tegos, Panagiotis D. Diamantoulakis, George K. Karagiannidis
This paper focuses on the latest research and innovations in fundamental next-generation multiple access (NGMA) techniques and the coexistence with other key technologies for the sixth generation (6G) of wireless networks.
no code implementations • 15 Mar 2022 • Yurong Qian, Jindan Xu, Shuhan Zhu, Wei Xu, Lisheng Fan, George K. Karagiannidis
In this paper, we consider a multiuser mobile edge computing (MEC) system, where a mixed-integer offloading strategy is used to assist the resource assignment for task offloading.
no code implementations • 11 Mar 2022 • Pavlos S. Bouzinis, Panagiotis D. Diamantoulakis, George K. Karagiannidis
The impact of the quantization error on the convergence time is evaluated and the trade-off among model accuracy and timely execution is revealed.
no code implementations • 17 Nov 2021 • Yan Liu, Yansha Deng, Maged Elkashlan, Arumugam Nallanathan, George K. Karagiannidis
To support these requirements, the third generation partnership project (3GPP) has introduced enhanced grant-free (GF) transmission in the uplink (UL), with multiple active configured-grants (CGs) for URLLC UEs.
no code implementations • 3 Nov 2021 • Stylianos E. Trevlakis, Alexandros-Apostolos A. Boulogeorgos, Nestor D. Chatzidiamantis, George K. Karagiannidis
Moreover, we formulate a model for the calculation of the absorption coefficient of any generic biological tissue.
no code implementations • 3 Jun 2021 • Tianqi Mao, Jiaxuan Chen, Qi Wang, Chong Han, Zhaocheng Wang, George K. Karagiannidis
Finally, a data-embedded MS-QP (DE-MS-QP) waveform is constructed through time-domain extension of the MS-QP sequence, generating null frequency points on each subband for data transmission.
no code implementations • 24 Apr 2021 • Pavlos S. Bouzinis, Panagiotis D. Diamantoulakis, George K. Karagiannidis
As it has been discussed in the first part of this work, the utilization of advanced multiple access protocols and the joint optimization of the communication and computing resources can facilitate the reduction of delay for wireless federated learning (WFL), which is of paramount importance for the efficient integration of WFL in the sixth generation of wireless networks (6G).
no code implementations • 24 Apr 2021 • Pavlos S. Bouzinis, Panagiotis D. Diamantoulakis, George K. Karagiannidis
Conventional machine learning techniques are conducted in a centralized manner.
no code implementations • 22 Feb 2021 • Sotirios K. Goudos, Achilles D. Boursianis, Ali Wagdy Mohamed, Shaohua Wan, Panagiotis Sarigiannidis, George K. Karagiannidis, Ponnuthurai N. Suganthan
To the best of the authors knowledge, this is the first time that LGSO algorithms are applied to the optimal power allocation problem in IoT networks.
no code implementations • 10 Feb 2021 • Sotiris A. Tegos, Dimitrios Tyrovolas, Panagiotis D. Diamantoulakis, George K. Karagiannidis
To facilitate the performance analysis of a RRS-assisted system, first, we present novel closed-form expressions for the probability density function, the cumulative distribution function, the moments, and the characteristic function of the distribution of the sum of double-Nakagami-m random vectors, whose amplitudes follow the double-Nakagami-m distribution, i. e., the distribution of the product of two Nakagami-m random variables, and phases follow the circular uniform distribution.
Information Theory Signal Processing Information Theory Applications
1 code implementation • 21 Jan 2021 • Ke He, Le He, Lisheng Fan, Yansha Deng, George K. Karagiannidis, Arumugam Nallanathan
Existing detection methods have mainly focused on specific noise models, which are not robust enough with unknown noise statistics.
1 code implementation • 7 Jan 2021 • Le He, Ke He, Lisheng Fan, Xianfu Lei, Arumugam Nallanathan, George K. Karagiannidis
This indicates that the proposed algorithm reaches almost the optimal efficiency in practical scenarios, and thereby it is applicable for large-scale systems.
no code implementations • 31 Oct 2020 • Yanyu Cheng, Kwok Hung Li, Yuanwei Liu, Kah Chan Teh, George K. Karagiannidis
More importantly, simulation results reveal that a 3-bit resolution for discrete phase shifts is sufficient to achieve near-optimal outage performance.
no code implementations • 11 Sep 2020 • Fang Fang, Yanqing Xu, Zhiguo Ding, Chao Shen, Mugen Peng, George K. Karagiannidis
We adopt the partial offloading policy, in which each user can partition its computation task into offloading and locally computing parts.
no code implementations • 17 Aug 2020 • Yuyao Sun, Wei Xu, Lisheng Fan, Geoffrey Ye Li, George K. Karagiannidis
Accurate channel state information (CSI) feedback plays a vital role in improving the performance gain of massive multiple-input multiple-output (m-MIMO) systems, where the dilemma is excessive CSI overhead versus limited feedback bandwith.
no code implementations • 5 Aug 2020 • Alexandros-Apostolos A. Boulogeorgos, Stylianos E. Trevlakis, Sotiris A. Tegos, Vasilis K. Papanikolaou, George K. Karagiannidis
Next, we discuss the state of the art ML methodologies that are used to countermeasure the aforementioned challenges.
no code implementations • 20 Jun 2020 • Stylianos E. Trevlakis, Alexandros-Apostolos A. Boulogeorgos, Nestor D. Chatzidiamantis, George K. Karagiannidis
In the present work, we introduce a novel cochlear implant (CI) architecture, namely all-optical CI (AOCI), which directly converts acoustic to optical signals capable of stimulating the cochlear neurons.
no code implementations • 18 Feb 2020 • Yan Liu, Yansha Deng, Maged Elkashlan, Arumugam Nallanathan, George K. Karagiannidis
Based on this framework, we define the latent access failure probability to characterize URLLC reliability and latency performances.