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Symeon Chatzinotas

The Rise of Intelligent Reflecting Surfaces in Integrated Sensing and Communications Paradigms


Apr 14, 2022
Ahmet M. Elbir, Kumar Vijay Mishra, M. R. Bhavani Shankar, Symeon Chatzinotas

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* 7pages5figures 
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Opportunities for Physical Layer Security in UAV Communication Enhanced with Intelligent Reflective Surfaces


Mar 31, 2022
Wali Ullah Khan, Eva Lagunas, Zain Ali, Muhammad Awais Javed, Manzoor Ahmed, Symeon Chatzinotas, Björn Ottersten, Petar Popovski

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Hybrid Active-Passive Reconfigurable Intelligent Surface-Assisted Multi-User MISO Systems


Mar 18, 2022
Nhan Thanh Nguyen, Van-Dinh Nguyen, Qingqing Wu, Antti Tolli, Symeon Chatzinotas, Markku Juntti

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* This paper has been submitted to IEEE International Workshop on Signal Processing Advances in Wireless Communications (SPAWC) 2022 
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Architectures and Synchronization Techniques for Distributed Satellite Systems: A Survey


Mar 16, 2022
Liz Martinez Marrero, Juan C. Merlano Duncan, Jorge Querol, Sumit Kumar, Jevgenij Krivochiza, Shree Krishna Sharma, Symeon Chatzinotas, Adriano Camps, Bjorn Otterstern

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* submitted to IEEE Access 
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Energy Efficiency Optimization for Backscatter Enhanced NOMA Cooperative V2X Communications under Imperfect CSI


Feb 16, 2022
Wali Ullah Khan, Muhammad Ali Jamshed, Eva Lagunas, Symeon Chatzinotas, Xingwang Li, Bjorn Ottersten

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On the Impacts of Phase Shifting Design and Eavesdropping Uncertainty on Secrecy Metrics of RIS-aided Systems


Feb 12, 2022
Long Kong, Steven Kisseleff, Symeon Chatzinotas, Björn Ottersten, Melike Erol-Kantarci

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* 6 pages, 7 figures, conference 
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Backscatter-Aided NOMA V2X Communication under Channel Estimation Errors


Feb 03, 2022
Wali Ullah Khan, Muhammad Ali Jamshed, Asad Mahmood, Eva Lagunas, Symeon Chatzinotas, Bjorn Ottersten


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When RIS Meets GEO Satellite Communications: A New Optimization Framework in 6G


Feb 01, 2022
Wali Ullah Khan, Eva Lagunas, Asad Mahmood, Symeon Chatzinotas, Bjorn Ottersten

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* 6, 5, IEEE ICC 2022 
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THz-Empowered UAVs in 6G: Opportunities, Challenges, and Trade-Offs


Jan 13, 2022
M. Mahdi Azari, Sourabh Solanki, Symeon Chatzinotas, Mehdi Bennis


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Active Terminal Identification, Channel Estimation, and Signal Detection for Grant-Free NOMA-OTFS in LEO Satellite Internet-of-Things


Jan 06, 2022
Xingyu Zhou, Keke Ying, Zhen Gao, Yongpeng Wu, Zhenyu Xiao, Symeon Chatzinotas, Jinhong Yuan, Björn Ottersten

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Effective Rate of RIS-aided Networks with Location and Phase Estimation Uncertainty


Dec 17, 2021
Long Kong, Steven Kisseleff, Symeon Chatzinotas, Björn Ottersten, Melike Erol-Kantarci

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* 5 pages, 6 figures, conference 
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Controlling Smart Propagation Environments: Long-Term versus Short-Term Phase Shift Optimization


Oct 25, 2021
Trinh Van Chien, Lam Thanh Tu, Dinh-Hieu Tran, Hieu Van Nguyen, Symeon Chatzinotas, Marco Di Renzo, Björn Ottersten

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* 5 pages, 1 figure. Submitted for publication 
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Multi-layer Space Information Networks: Access Design and Softwarization


Oct 15, 2021
Hayder Al-Hraishawi, Mario Minardi, Houcine Chougrani, Oltjon Kodheli, Jesus Fabian Mendoza Montoya, Symeon Chatzinotas

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* arXiv admin note: text overlap with arXiv:2107.05312 
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Adapting to Dynamic LEO-B5G Systems: Meta-Critic Learning Based Efficient Resource Scheduling


Oct 13, 2021
Yaxiong Yuan, Lei lei, Thang X. Vu, Zheng Chang, Symeon Chatzinotas, Sumei Sun

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* 12 pages, 9 figures 
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Joint Optimization of Beam-Hopping Design and NOMA-Assisted Transmission for Flexible Satellite Systems


Oct 13, 2021
Anyue Wang, Lei Lei, Eva Lagunas, Ana I. Perez-Neira, Symeon Chatzinotas, Bjorn Ottersten

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Integration of Backscatter Communication with Multi-cell NOMA: A Spectral Efficiency Optimization under Imperfect SIC


Sep 26, 2021
Wali Ullah Khan, Eva Lagunas, Asad Mahmood, Symeon Chatzinotas, Björn Ottersten

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* 5 pages, 3 figures 
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Robust Congestion Control for Demand-Based Optimization in Precoded Multi-Beam High Throughput Satellite Communications


Sep 06, 2021
Van-Phuc Bui, Trinh Van Chien, Eva Lagunas, Joël Grotz, Symeon Chatzinotas, Björn Ottersten

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* 30 pages, 11 figures, and 1 table. Submitted to the IEEE for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessible 
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Toward Autonomous Reconfigurable Intelligent Surfaces Through Wireless Energy Harvesting


Aug 18, 2021
Konstantinos Ntontin, Alexandros-Apostolos A. Boulogeorgos, Emil Björnson, Dimitrios Selimis, Wallace Alves Martins, Steven Kisseleff, Sergi Abadal, Eduard Alarcón, Anastasios Papazafeiropoulos, Fotis Lazarakis, Angeliki Alexiou, Symeon Chatzinotas

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* 31 pages, 8 figures 
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Frequency-packed Faster-than-Nyquist Signaling via Symbol-level Precoding for Multi-user MISO Redundant Transmissions


Jul 14, 2021
Wallace A. Martins, Symeon Chatzinotas, Björn Ottersten

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Evolution of Non-Terrestrial Networks From 5G to 6G: A Survey


Jul 14, 2021
M. Mahdi Azari, Sourabh Solanki, Symeon Chatzinotas, Oltjon Kodheli, Hazem Sallouha, Achiel Colpaert, Jesus Fabian Mendoza Montoya, Sofie Pollin, Alireza Haqiqatnejad, Arsham Mostaani, Eva Lagunas, Bjorn Ottersten

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A Survey on Non-Geostationary Satellite Systems: The Communication Perspective


Jul 12, 2021
Hayder Al-Hraishawi, Houcine Chougrani, Steven Kisseleff, Eva Lagunas, Symeon Chatzinotas

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Reconfigurable Intelligent Surface-Assisted Massive MIMO: Favorable Propagation, Channel Hardening, and Rank Deficiency


Jul 07, 2021
Trinh Van Chien, Hien Quoc Ngo, Symeon Chatzinotas, Björn Ottersten

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* 10 pages, 2 Figures. Submitted to IEEE for possible publication on May 5th, 2021 
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FedFog: Network-Aware Optimization of Federated Learning over Wireless Fog-Cloud Systems


Jul 04, 2021
Van-Dinh Nguyen, Symeon Chatzinotas, Bjorn Ottersten, Trung Q. Duong

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* 30 pages, 12 figures. This work has been submitted to the IEEE for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessible 
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LEO Satellite Constellations for 5G and Beyond: How Will They Reshape Vertical Domains?


Jun 18, 2021
Shicong Liu, Zhen Gao, Yongpeng Wu, Derrick Wing Kwan Ng, Xiqi Gao, Kai-Kit Wong, Symeon Chatzinotas, Bjorn Ottersten

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* 4 figures, 1 table, accepted by Communications Magazine 
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Satellite- and Cache-assisted UAV: A Joint Cache Placement, Resource Allocation, and Trajectory Optimization for 6G Aerial Networks


Jun 09, 2021
Dinh-Hieu Tran, Symeon Chatzinotas, Björn Ottersten

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* 14 pages, 6 figures 
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What Will the Future of UAV Cellular Communications Be? A Flight from 5G to 6G


May 11, 2021
Giovanni Geraci, Adrian Garcia-Rodriguez, M. Mahdi Azari, Angel Lozano, Marco Mezzavilla, Symeon Chatzinotas, Yun Chen, Sundeep Rangan, Marco Di Renzo

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Hybrid Relay-Reflecting Intelligent Surface-Aided Wireless Communications: Opportunities, Challenges, and Future Perspectives


Apr 05, 2021
Nhan Thanh Nguyen, Jiguang He, Van-Dinh Nguyen, Henk Wymeersch, Derrick Wing Kwan Ng, Robert Schober, Symeon Chatzinotas, Markku Juntti

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