no code implementations • 2 May 2024 • Yuma Abe, Flor Ortiz, Eva Lagunas, Victor Monzon Baeza, Symeon Chatzinotas, Hiroyuki Tsuji
Satellite constellation systems are becoming more attractive to provide communication services worldwide, especially in areas without network connectivity.
no code implementations • 19 Apr 2024 • Flor Ortiz, Eva Lagunas, Almoatssimbillah Saifaldawla, Mahdis Jalali, Luis Emiliani, Symeon Chatzinotas
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.
no code implementations • 12 Jan 2024 • Eva Lagunas, Flor Ortiz, Geoffrey Eappen, Saed Daoud, Wallace Alves Martins, Jorge Querol, Symeon Chatzinotas, Nicolas Skatchkovsky, Bipin Rajendran, Osvaldo Simeone
Spiking neural networks (SNNs) implemented on neuromorphic processors (NPs) can enhance the energy efficiency of deployments of artificial intelligence (AI) for specific workloads.
no code implementations • 2 Nov 2023 • Flor Ortiz, Juan A. Vasquez-Peralvo, Jorge Querol, Eva Lagunas, Jorge L. Gonzalez Rios, Marcele O. K. Mendonca, Luis Garces, Victor Monzon Baeza, Symeon Chatzinotas
Satellite communications (SatCom) are crucial for global connectivity, especially in the era of emerging technologies like 6G and narrowing the digital divide.
no code implementations • 2 Nov 2023 • Juan Andrés Vásquez-Peralvo, Jorge Querol, Eva Lagunas, Flor Ortiz, Luis Manuel Garcés-Socarrás, Jorge Luis González-Rios, Victor Monzon Baeza, Symeon Chatzinotas
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.
no code implementations • 18 Oct 2023 • Marcele O. K. Mendonca, Flor G. Ortiz-Gomez, Jorge Querol, Eva Lagunas, Juan A. Vásquez Peralvo, Victor Monzon Baeza, Symeon Chatzinotas, Bjorn Ottersten
Satellite communications, essential for modern connectivity, extend access to maritime, aeronautical, and remote areas where terrestrial networks are unfeasible.
no code implementations • 25 Sep 2023 • Flor Ortiz, Juan A. Vasquez-Peralvo, Jorge Querol, Eva Lagunas, Jorge L. Gonzalez Rios, Luis Garces, Victor Monzon-Baeza, Symeon Chatzinotas
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.
no code implementations • 21 Sep 2023 • Wali Ullah Khan, Eva Lagunas, Zain Ali, Asad Mahmood, Chandan Kumar Sheemar, Manzoor Ahmed, Symeon Chatzinotas, Björn Ottersten
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.
no code implementations • 19 Sep 2023 • Victor Monzon Baeza, Flor Ortiz, Eva Lagunas, Tedros Salih Abdu, Symeon Chatzinotas
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.
no code implementations • 6 Sep 2023 • Wali Ullah Khan, Asad Mahmood, Chandan Kumar Sheemar, Eva Lagunas, Symeon Chatzinotas, Björn Ottersten
This paper studies the potential of RIS-integrated NTNs to revolutionize the next-generation connectivity.
no code implementations • 22 Aug 2023 • Flor Ortiz, Nicolas Skatchkovsky, Eva Lagunas, Wallace A. Martins, Geoffrey Eappen, Saed Daoud, Osvaldo Simeone, Bipin Rajendran, Symeon Chatzinotas
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.
no code implementations • 29 Jul 2023 • Wali Ullah Khan, Eva Lagunas, Asad Mahmood, Zain Ali, Symeon Chatzinotas, Björn Ottersten
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.
no code implementations • 17 Jun 2023 • Wali Ullah Khan, Eva Lagunas, Asad Mahmood, Symeon Chatzinotas, Björn Ottersten
Then, in step 2, given the transmit power, we design passive beamforming for RIS by solving the semi-definite programming.
no code implementations • 17 May 2023 • Van-Phuc Bui, Thinh Q. Dinh, Israel Leyva-Mayorga, Shashi Raj Pandey, Eva Lagunas, Petar Popovski
The amount of data generated by Earth observation satellites can be enormous, which poses a great challenge to the satellite-to-ground connections with limited rate.
no code implementations • 26 Apr 2023 • Vu Nguyen Ha, Juan Carlos Merlano Duncan, Eva Lagunas, Jorge Querol, Symeon Chatzinotas
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.
no code implementations • 19 Mar 2023 • Hung Nguyen-Kha, Vu Nguyen Ha, Eva Lagunas, Symeon Chatzinotas, Joel Grotz
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.
no code implementations • 11 Mar 2023 • Vu Nguyen Ha, Eva Lagunas, Tedros Salih Abdu, Haythem Chaker, Symeon Chatzinotas, Joel Grotz
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.
no code implementations • 9 Mar 2023 • Wali Ullah Khan, Eva Lagunas, Asad Mahmood, Symeon Chatzinotas, Björn Ottersten
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.
no code implementations • 2 Feb 2023 • Hung Nguyen-Kha, Vu Nguyen Ha, Eva Lagunas, Symeon Chatzinotas, Joel Grotz
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).
no code implementations • 5 Oct 2022 • Wali Ullah Khan, Muhammad Awais Javed, Sherali Zeadally, Eva Lagunas, Symeon Chatzinotas
We present an overview of enabling technologies for ISRE-based 6G vehicular aided HetNets.
no code implementations • 2 Oct 2022 • Wali Ullah Khan, Asad Mahmood, Arash Bozorgchenani, Muhammad Ali Jamshed, Ali Ranjha, Eva Lagunas, Haris Pervaiz, Symeon Chatzinotas, Björn Ottersten, Petar Popovski
This paper first describes the introduction of 6G-empowered V2X communications and IRS technology.
no code implementations • 21 Sep 2022 • Victor Monzon Baeza, Eva Lagunas, Hayder Al-Hraishawi, Symeon Chatzinotas
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.
no code implementations • 22 Aug 2022 • Vu Nguyen Ha, Ti Ti Nguyen, Eva Lagunas, Juan Carlos Merlano Duncan, Symeon Chatzinotas
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.
no code implementations • 4 Aug 2022 • Wali Ullah Khan, Zain Ali, Eva Lagunas, Symeon Chatzinotas, Björn Ottersten
We also propose two suboptimal schemes with fixed power allocation and random subcarrier beam assignment as the benchmark.
no code implementations • 24 Jun 2022 • Mirza Golam Kibria, Hayder Al-Hraishawi, Eva Lagunas, Symeon Chatzinotas, Björn Ottersten
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.
no code implementations • 6 May 2022 • Wali Ullah Khan, Eva Lagunas, Asad Mahmood, Zain Ali, Muhammad Asif Symeon Chatzinotas, Björn Ottersten
Reflecting intelligent surfaces (RIS) has gained significant attention due to its high energy and spectral efficiency in next-generation wireless networks.
no code implementations • 31 Mar 2022 • Wali Ullah Khan, Eva Lagunas, Zain Ali, Muhammad Awais Javed, Manzoor Ahmed, Symeon Chatzinotas, Björn Ottersten, Petar Popovski
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.
no code implementations • 3 Feb 2022 • Wali Ullah Khan, Muhammad Ali Jamshed, Asad Mahmood, Eva Lagunas, Symeon Chatzinotas, Bjorn Ottersten
Then the RSUs transmit the superimposed signal to their serving vehicles in the second time slot exploiting decode and forward protocol.
no code implementations • 3 Feb 2022 • Wali Ullah Khan, Muhammad Ali Jamshed, Eva Lagunas, Symeon Chatzinotas, Xingwang Li, Bjorn Ottersten
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.
no code implementations • 1 Feb 2022 • Wali Ullah Khan, Eva Lagunas, Asad Mahmood, Symeon Chatzinotas, Bjorn Ottersten
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.
no code implementations • 23 Sep 2021 • Wali Ullah Khan, Eva Lagunas, Asad Mahmood, Zain Ali, Symeon Chatzinotas, Björn Ottersten, Octavia A. Dobre
This paper proposes a new optimization approach to enhance the spectral efficiency of nonorthogonal multiple access (NOMA)-BC network.
no code implementations • 12 Jul 2021 • Hayder Al-Hraishawi, Houcine Chougrani, Steven Kisseleff, Eva Lagunas, Symeon Chatzinotas
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.
no code implementations • 2 Nov 2020 • Bhavani Shankar Mysore, Eva Lagunas, Symeon Chatzinotas, Bjorn Ottersten
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.
1 code implementation • 14 Jul 2020 • Hayder Al-Hraishawi, Eva Lagunas, Symeon Chatzinotas
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.