A5065550137- Optical Wireless Communication Technologies
- Optical Network Technologies
- Advanced Photonic Communication Systems
- Satellite Communication Systems
- graph theory and CDMA systems
- Advanced Wireless Communication Technologies
- Image and Video Quality Assessment
- Advanced Optical Network Technologies
- Coding theory and cryptography
- Video Coding and Compression Technologies
- UAV Applications and Optimization
- Semiconductor Lasers and Optical Devices
- Advanced Data Compression Techniques
- Quantum Information and Cryptography
- Energy Harvesting in Wireless Networks
- Wireless Communication Networks Research
- Radio Wave Propagation Studies
- Quantum Computing Algorithms and Architecture
- Multimedia Communication and Technology
- Advanced Wireless Communication Techniques
- IoT and Edge/Fog Computing
- Wireless Communication Security Techniques
- PAPR reduction in OFDM
- Orbital Angular Momentum in Optics
- RFID technology advancements
University of Aizu
2016-2025
Deloitte (United States)
2022-2025
Posts and Telecommunications Institute of Technology
2022-2024
Vietnam Posts and Telecommunications Group (Vietnam)
2022-2024
University of California, San Diego
2019-2024
Hanoi University of Science and Technology
2017-2023
University of Economics Ho Chi Minh City
2023
Phenikaa University
2022
Phenikaa (Vietnam)
2022
Carleton University
2022
HTTP streaming has become a cost effective means for multimedia delivery nowadays. In this paper, we study the use of MPEG DASH standard to stream audiovisual content. We first describe novel estimation method connection throughput. Then, employing extensibility feature syntax, present systematic selecting best audio and video alternatives given estimated The experiments show that our solution is stable short-term fluctuations while responding quickly large fluctuations.
HTTP streaming has become a cost-effective means for multimedia delivery nowadays. For adaptivity to networks and terminals, provider should generate multiple representations of an original video as well the related metadata. Recently, there have been various adaptation methods support adaptive streaming. In this paper, we investigate typical in context live We first discuss trade-off among methods. The evaluation comparison are then carried out not only terms bitrate buffer behaviors but...
This paper studies the performance of mixed millimeter-wave radio-frequency (mmWave RF), free-space optics (FSO) systems in a highly scalable and cost-effective solution for fifth-generation (5G) mobile backhaul networks. The mmWave RF FSO fading channels are, respectively, modeled by Rician generalized Malaga (M) distributions. effect pointing errors due to misalignment between transmitter receiver link is also included. Novel accurate closed-form expressions cumulative distribution...
This paper studies zero-forcing (ZF) precoding designs for multi-user multiple-input single-output visible light communication (VLC) broadcast channels. In such systems, the main challenging issue arises from presence of interference (MUI) among non-coordinated users. order to completely suppress MUI, ZF precoding, which is originally designed radio frequency (RF) communications, adopted. Different RF counterpart, VLC signal inherently non-negative and has a limited linear range, leads an...
In this paper, we propose a new adaptation approach for viewport-adaptive streaming of 360-degree videos over the Internet. The proposed is able to systematically decide versions tiles according user head movements and network conditions by taking into account not only viewport estimation errors, but also users in each segment duration. experimental results show that can effectively adapt both varying user's movements. Compared existing approaches, improve average quality up 3.8 dB reduce...
<h3>Importance</h3> Patients increasingly demand transparency in and control of how their medical records biospecimens are shared for research. How much they willing to share what factors influence sharing preferences remain understudied real settings. <h3>Objectives</h3> To examine whether various presentations consent forms associated with differences electronic health record biospecimen rates these vary according user interface design, data recipients, items, patient characteristics....
Satellite-aerial-ground integrated network (SAGIN) has been widely envisioned as a promising architecture for 6 G. In the SAGINs, high altitude platform (HAP)-aided relaying satellite systems using hybrid free-space optics (FSO)/radio-frequency (RF) communications have recently attracted research efforts worldwide. Nevertheless, main drawback of FSO/RF is restricted bandwidth RF connection, especially when FSO one blocked by cloud coverage. This paper explores novel solution HAP-based SAGIN...
We theoretically analyze the performance of free-space optical (FSO) systems using rectangular quadrature-amplitude modulation (QAM) and an avalanche photodiode (APD) receiver over atmospheric turbulence channels. Both log-normal gamma–gamma channel models are used in analysis for cases weak/moderate strong turbulence. The system bit error rate, when Gray code mapping is employed, derived taking into account various link conditions parameters, including APD shot noise, thermal...
In this study, the authors theoretically study performance of direct‐detection free‐space optical communication systems using binary phase‐shift keying subcarrier‐intensity modulation and avalanche photodiode (APD). The system bit‐error rate channel capacity are derived in cases log‐normal gamma‐gamma models for weak‐to‐moderate moderate‐to‐strong atmospheric turbulence conditions, respectively. quantitatively discuss optimal values APD average gain, required transmitted power, operating...
This paper addresses the design of hybrid free-space optical/radio frequency (FSO/RF) systems for a high-altitude platform (HAP)-aided relaying satellite communication mobile networks supported by unmanned aerial vehicle (UAV). While prior work primarily focused on fixed-rate design, which frequently switches between FSO and RF lead reduced system performance, we propose rate adaptation that gradually adjusts data in each link when its channel state fluctuates, under target bit error (BER)...
Surface-enhanced Raman scattering (SERS) is a powerful analysis technique that allows both the identification and detection of analytes at trace levels. However, low rate charge transfer (CT) between noble-metal nanoparticles several prevents them from being effectively detected by SERS-based sensors. They are regarded as cross-section molecules. In this study, we enhanced performance silver (AgNPs)-based SERS sensing platform for molecule, urea, focusing on improving CT. First, set...
Mobile Edge Computing (MEC) is a key technology towards delay-sensitive and computation-intensive applications in future cellular networks. In this paper, we consider multi-user, multi-server system where the base station assisted by UAV, both of which provide additional MEC services to terrestrial users. Via dual connectivity (DC), each user can simultaneously offload tasks macro UAV-mounted server for parallel computing, while also processing some locally. We aim propose an online resource...
Adaptive hypertext transfer protocol (HTTP) streaming has become a new trend to support adaptivity in video delivery. An HTTP client needs estimate exactly resource availability and demand. In this paper, we focus on the most important which is bandwidth. A general formulation for throughput estimation presented taking into account previous values of instant round trip time. Besides, introduce first time use bitrate streaming. The experiments show that our approach can effectively cope with...
This paper proposes a novel design and analyzes security performance of quantum key distribution (QKD) protocol over free-space optics (FSO). Unlike conventional QKD protocols based on physical characteristics mechanics, the proposed can be implemented standard FSO systems using subcarrier intensity modulation binary phase shift keying direct detection with dual-threshold receiver. Under constraints, criteria for transmitter receiver, in particular, depth selection detection, respectively,...
In this paper, a novel relaying technique is proposed to improve the bit-error rate (BER) performance and distance coverage of high-speed all-optical free-space optical (FSO) communication systems. Particularly, an amplify-and-forward (OAF) using erbium-doped fiber amplifier (EDFA) combined with hard-limiter (OHL) introduced. The use OHL enables EDFA-based OAF FSO systems prevent accumulation amplified background noise, which significantly degrades system performance, when deploying multiple...
We investigate the primary user emulation (PUE) attack, which is a serious security problem in cognitive radio (CR) networks. There exist three types of PUE attackers: 1) selfish one, aims at maximizing its usage channel resource; 2) malicious points for obstructing operation CR network; and 3) mixed between attacker. For combating attacker, surveillance process has to be implemented order determine active user's identification so An extra-sensing observing new opportunities access...
This paper investigates the second-order statistics of level crossing rate (LCR) and average fade duration (AFD) for optical wireless channels between a satellite vehicle. Specifically, novel expressions LCR AFD low earth orbit (LEO) satellite-to-unmanned aerial vehicles (UAVs) laser links are derived in presence generalized misalignments caused by vibration together with UAV hovering, which is modeled four-parameter Beckmann distribution, atmospheric turbulence conditions. The analysis can...
This letter addresses the attenuation statistics due to clouds on satellite-based free-space optical communications. Specifically, we present a novel distribution model of monthly cloud for several regions in Japan. To this purpose, five-year reanalysis meteorological database, namely, ERA-Interim, produced from European Center Medium-Range Weather Forecast (ECMWF), is investigated. The liquid water content (CLWC) obtained ECMWF ERA-interim database used determine attenuation. curve-fitting...
Free space optical (FSO) communication has established a reputation for itself capable of delivering high-speed data services over long distances without exhausting radio frequency (RF) resources. FSO can be considered in different network scenarios, including inter-satellite/deep-space links, ground-station/vehicles, satellite/aerial and terrestrial links. It is expected to one the key enabling technologies next generation 6G wireless networks. Nevertheless, despite great potential...
We aimed to develop a distributed, immutable, and highly available cross-cloud blockchain system facilitate federated data analysis activities among multiple institutions.
This paper proposes a joint design of probabilistic constellation shaping (PCS) and precoding to enhance the sum-rate performance multi-user visible light communications (VLC) broadcast channels subject signal amplitude constraint. In proposed design, transmission probabilities bipolar $M$-pulse modulation ($M$-PAM) symbols for each user transmit matrix are jointly optimized improve performance. The problem is shown be complex multivariate non-convex due non-convexity objective function. To...
Abstract With the constant flow of data from vast sources over past decades, a plethora advanced analytical techniques have been developed to extract relevant information different types ranging labeled data, quasi‐labeled and with no labels known priori. For at best quasi‐labels, graphs are natural representation important applications in many industries scientific disciplines. Specifically, for unlabeled anomaly detection on is method determine which points do not posses latent...