Article
Engineering, Electrical & Electronic
Hui Zhao, Mohamed-Slim Alouini
Summary: The paper investigates the transmission probabilities in quantum key distribution systems under three cases and a generalized pointing error scenario. Approximate expressions of transmission probabilities are derived using the Gaussian quadrature method, and asymptotic analysis is conducted based on asymptotic expression for the generalized Marcum Q-function. The results show that the asymptotic outage probability over Beckmann fading channels can be easily derived when the telescope gain at the legitimate receiver approaches infinity.
IEEE TRANSACTIONS ON COMMUNICATIONS
(2021)
Article
Engineering, Electrical & Electronic
Guanjun Xu, Zhaohui Song
Summary: Mixed RF/FSO systems are investigated in this paper, considering asymmetric fading environments. Closed-form expressions for CDF and PDF, as well as outage probability, average BER, and ergodic capacity under various modulation schemes, are presented. Tight asymptotic formulae for outage probability and average BER at high SNR regime are also derived, providing insights into system performance.
IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS
(2021)
Editorial Material
Nanoscience & Nanotechnology
Alan E. Willner, Cong Liu
Summary: Structured light is a promising technology for increasing communication capacity by transmitting multiple orthogonal beams simultaneously. Future challenges lie in utilizing multiple orbital angular momentum modes to enhance system performance.
Article
Engineering, Civil
Ruben Boluda-Ruiz, Pedro Salcedo-Serrano, Beatriz Castillo-Vazquez, Antonio Garcia-Zambrana, Jose Maria Garrido-Balsells
Summary: The article investigates the physical layer security aspects in underwater optical wireless communication (UOWC) systems, with a focus on the transmission of large and secure amounts of data. The secrecy outage probability (SOP) is carefully studied in Weibull oceanic turbulence channels with angular misalignment errors affected by absorption and scattering. Novel approximate closed-form solutions for SOP are derived and validated with Monte Carlo simulations in various real scenarios, such as clear ocean and coastal waters with determined chlorophyll-a concentration.
IEEE JOURNAL OF OCEANIC ENGINEERING
(2023)
Article
Engineering, Electrical & Electronic
Crisanto Quintana, Qin Wang, Darius Jakonis, Olof Oberg, Gavin Erry, Duncan Platt, Yoann Thueux, Grahame Faulkner, Hyunchae Chun, Ariel Gomez, Michael Salter, Dominic C. OaBrien
Summary: This work describes the design and implementation of a high-speed retro-reflective free space communication system using an electro-absorption modulator modulating retro-reflector, achieving a high data rate and low error rate. Successful outdoor trials were conducted to demonstrate the system's performance.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Computer Science, Information Systems
Javier Garcia Olmedo, Victor P. Gil Jimenez
Summary: This paper studies the influence of atmospheric conditions on visibility in Free Space Optical Communications (FSOC) and provides a performance analysis. It focuses on ground station-satellite links and analyzes commonly used attenuation models for different atmospheric events, establishing relationships and dependencies, including rain and snow. The paper suggests using visibility as a single parameter to compare and analyze atmospheric events and proposes new techniques for calculating link blockage in the presence of clouds. The paper also lists the sources of meteorological parameters and tools used in the study.
Article
Telecommunications
Siming Wang, Mugen Peng, Renzhi Yuan
Summary: This paper investigates the problem of turbulence interference in free-space optical communication with photon-counting receivers and proposes the use of spatial diversity techniques to mitigate its impact. The study shows that under non-turbulent conditions, maximum likelihood detection is equivalent to threshold detection, which can effectively reduce errors.
IEEE COMMUNICATIONS LETTERS
(2023)
Article
Optics
Chi Geng, Siyuan Yu, Gaoyuan Lu, Yiqun Wang
Summary: In this paper, the impact of correlated atmospheric turbulence (AT) channels on the performance of coherent free-space optical (FSO) communication systems using optical spatial modulation (OSM) is studied. The authors assume that the correlated AT channels follow the Gamma-Gamma distribution and propose a coherent FSO-OSM system model. They derive closed-form approximated expressions for the average symbol error probability (ASEP) and examine the effects of signal constellation and spatial constellation on OSM under different conditions. The authors also investigate the relationships between the ASEP caused by signal and spatial constellation and the strength and correlation of AT. Furthermore, they analyze the impact of correlation coefficients resulting from large-scale and small-scale eddies on the system performance under varying AT conditions. Simulation results confirm the theoretical findings and demonstrate that increased AT severity and correlation coefficients can degrade the performance of coherent OSM.
Article
Engineering, Electrical & Electronic
Alexander C. MacGillivray, Sayra Gorgani, Ilija R. Hristovski, Matthias F. Jenne, Nikolai I. Lesack, Jonathan F. Holzman
Summary: In this study, we present a hemispherical retro-modulator for passive free-space optical communication links. By incorporating high-refractive-index glass and semi-insulating materials, we achieved strong retroflection and modulation. This modulator can improve the performance of passive optical communication links.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2022)
Article
Physics, Multidisciplinary
Gamze Nur Secilmis, Kholoud Elmabruk
Summary: In this study, the numerical investigation is conducted to explore the ability of laser beams carrying orbital angular momentum to reduce the scintillation level of Gaussian beams propagating in atmospheric turbulence. The effects of topological charge, beam waist, operating wavelength, and receiver radius on the scintillation indices are examined in detail. The results show that the Gaussian beams carrying orbital angular momentum have an advantage over fundamental Gaussian beams in communication links longer than 2.5 Km. It is also found that Gaussian beams carrying orbital angular momentum with small beam waist and high wavelength can significantly reduce the scintillation index. Therefore, these findings are significant for the design of optical communication links utilizing laser beams carrying orbital angular momentum.
Article
Engineering, Electrical & Electronic
Oskars Ozolins, Mahdieh Joharifar, Toms Salgals, Hadrien Louchet, Richard Schatz, Markus Gruen, Thomas Dippon, Benjamin Kruger, Fabio Pittala, Di Che, Yasuhiro Matsui, Yuchuan Fan, Aleksejs Udalcovs, Urban Westergren, Lu Zhang, Xianbin Yu, Sandis Spolitis, Vjaceslavs Bobrovs, Sergei Popov, Xiaodan Pang
Summary: The requirement to upgrade short-reach optical links to 1.6 TbE capacity in an economically viable way due to enormous traffic growth is set to be strict. High baudrate on-off keying links offer a possible solution with lower power consumption and latency. In this study, we demonstrate the performance of various modulation formats, including 200 Gbaud on-off keying, 108 Gbaud on-off keying, 112 Gbaud four-level pulse amplitude modulation, and 100 Gbaud six-level pulse amplitude modulation, achieving satisfactory results in terms of bit error rate and transmission distance.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Computer Science, Information Systems
Mohammed Elamassie, Murat Uysal
Summary: This study proposes a feedback-free adaptive modulation selection algorithm for Free Space Optical (FSO) communication systems, which aims to maximize average throughput by selecting the largest modulation order while ensuring that the required transmit power does not exceed the maximum power. Numerical results confirm the superiority of the proposed adaptive algorithm.
IEEE WIRELESS COMMUNICATIONS LETTERS
(2021)
Review
Environmental Sciences
Md Abdus Samad, Feyisa Debo Diba, Dong-You Choi
Summary: Satellite communication is a promising transmission technique for implementing 5G and beyond networks. Rain attenuation modeling is significant for propagating electromagnetic waves to achieve the required quality of service. This survey examines different slant link rain attenuation prediction models and provides various techniques for obtaining input data sets.
Article
Chemistry, Analytical
Joao H. Araujo, Joana S. Tavares, Veridiano M. Marques, Henrique M. Salgado, Luis M. Pessoa
Summary: This paper proposes a multiple-lens receiver scheme to increase the misalignment tolerance of an underwater optical wireless communications link between an AUV and a sensor plane. The Monte Carlo simulation accurately models photon propagation, accounting for lens refraction and angular misalignment. The study shows that a seven-lens scheme is three times more tolerant to offset than a single lens. Additionally, a random forest machine learning algorithm is able to estimate offset and angular misalignment with low mean square error for different transmission distances.
Article
Physics, Multidisciplinary
Halit Bakir, Kholoud Elmabruk
Summary: This study develops a deep-learning-based approach to detect turbulence-induced mode distortion in free-space optical communication links utilizing orbital angular momentum. The proposed models are trained with a dataset created based on intensity beam profiles propagated in different turbulent atmospheres. The results show that the proposed approach achieves high accuracy in distinguishing and quantifying the distortion in transmitted beams.
Article
Engineering, Electrical & Electronic
Ruben Boluda-Ruiz, Pedro Rico-Pinazo, Beatriz Castillo-Vazquez, Antonio Garcia-Zambrana, Khalid Qaraqe
IEEE PHOTONICS JOURNAL
(2020)
Article
Engineering, Electrical & Electronic
Ruben Boluda-Ruiz, Sezer Can Tokgoz, Antonio Garcia-Zambrana, Khalid Qaraqe
IEEE PHOTONICS JOURNAL
(2020)
Article
Optics
Ruben Boluda-Ruiz, Antonio Garcia-Zambrana, Beatriz Castillo-Vazquez, Steve Hranilovic
Article
Optics
Pedro Salcedo-Serrano, Ruben Boluda-Ruiz, Jose Maria Garrido-Balsells, Antonio Garcia-Zambrana
Summary: Recent research emphasizes the importance of accurate underwater channel characterization for improving the performance of underwater optical wireless communication systems. A new fading model is proposed to analyze the impact of scattering-induced fading on system performance. Results show that smaller diversity order values are achieved when considering scattering-induced fading, highlighting the need to always consider scattering in fading analysis for advanced UOWC system designs.
Article
Optics
Ruben Boluda-Ruiz, Pedro Salcedo-Serrano, Beatriz Castillo-Vazquez, Antonio Garcia-Zambrana, Jose Maria Garrido-Balsells
Summary: This paper analyzes the channel capacity of UOWC systems in the presence of inter-symbol interference and salinity-induced oceanic turbulence when accurately modeling the undersea optical channel. The results show that the capacity-achieving distribution is discrete and depends on the optical signal-to-noise ratio. Non-uniform input distribution significantly improves the channel capacity, especially at low optical SNR levels, for systems affected by ISI and oceanic turbulence.
Article
Mathematics
Fco Javier Giron, Carmen del Castillo
Summary: The paper presents a simple solution to the Behrens-Fisher problem based on Bayes factors, exploring its relation with the Behrens-Fisher distribution. The Bayes factor is constructed using a simple hierarchical model and a closed form based on the densities of general Behrens-Fisher distributions. Additionally, simple asymptotic approximations of the Bayes factor, functions of the Kullback-Leibler divergence between normal distributions, are provided along with evidence of its consistency, accompanied by examples and comparisons.
REVISTA DE LA REAL ACADEMIA DE CIENCIAS EXACTAS FISICAS Y NATURALES SERIE A-MATEMATICAS
(2021)
Article
Engineering, Civil
Ruben Boluda-Ruiz, Pedro Salcedo-Serrano, Beatriz Castillo-Vazquez, Antonio Garcia-Zambrana, Jose Maria Garrido-Balsells
Summary: The article investigates the physical layer security aspects in underwater optical wireless communication (UOWC) systems, with a focus on the transmission of large and secure amounts of data. The secrecy outage probability (SOP) is carefully studied in Weibull oceanic turbulence channels with angular misalignment errors affected by absorption and scattering. Novel approximate closed-form solutions for SOP are derived and validated with Monte Carlo simulations in various real scenarios, such as clear ocean and coastal waters with determined chlorophyll-a concentration.
IEEE JOURNAL OF OCEANIC ENGINEERING
(2023)
Proceedings Paper
Telecommunications
Pedro Salcedo-Serrano, Ruben Boluda-Ruiz, Jose Maria Garrido-Balsells, Antonio Garcia-Zambrana
Summary: This paper addresses the performance analysis of underwater optical wireless communication systems under scattering-induced fading channel, and provides closed-form expressions to compute the average capacity. The results show that scattering-induced fading is a critical degrading effect in turbid water environments.
IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS (ICC 2022)
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Ruben Boluda-Ruiz, Pedro Salcedo-Serrano, Beatriz Castillo-Vazquez, Antonio Garcia-Zambrana, Jose Maria Garrido-Balsells
Summary: New insights are provided on the impact of scattering-induced ISI and oceanic turbulence on channel capacity and mutual information of underwater optical wireless links when binary input constraint is imposed on the channel input and non-uniform OOK modulation is considered.
2021 ANNUAL CONFERENCE OF THE IEEE PHOTONICS SOCIETY (IPC)
(2021)
Proceedings Paper
Engineering, Electrical & Electronic
Pedro Salcedo-Serrano, Ruben Boluda-Ruiz, Jose Maria Garrido-Balsells, Antonio Garcia-Zambrana
Summary: We propose a novel probability density function to statistically describe the effect of scattering-induced fading in underwater FSO links for clear ocean and coastal waters, achieving a coefficient of determination R-2 above 0.9.
2021 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO)
(2021)