Results 41 to 50 of about 1,366,396 (241)
Review of Optical Wireless Communications Technologies in Different Operational Environments [PDF]
Problemy MechatronikiThis article examines existing technologies for free-space optical communications in both the atmosphere and water, with an emphasis on their practical potential.
Zbigniew BIELECKI (zbigniew.bielecki@wat.edu.pl) +1 more
doaj +1 more source
Waveguide Photoactuators: Materials, Fabrication, and Applications
Advanced Robotics Research, EarlyView.Waveguide photoactuators convert guided light into mechanical motion. Their tethered‐flexible design enables minimally invasive surgery and confined‐space robotics. This review aims to guide materials selection, device design, and system integration, accelerating the transition of waveguide photoactuators from laboratory prototypes to versatile ...
Minjie Xi +4 more
wiley +1 more source
The Acoustic System of the Fendouzhe HOV
Sensors, 2021 Due to the strong absorption and attenuation of electromagnetic waves by water, radio communications and global positioning systems are lacking in the deep-sea environment.
Yeyao Liu +10 more
doaj +1 more source
Laser based underwater communication systems [PDF]
2016 18th International Conference on Transparent Optical Networks (ICTON), 2016 We report on recent progress in the field of visible light communications including direct modulation of blue laser devices at data rates beyond 10 Gbit/s, and the transmission of 2.5 Gbit/s OOK data through water. We also discuss the advantages of operating with single mode laser devices and matched filtering at the receiver in the context of ...
Giuliano, Giovanni +5 more
openaire +1 more source
Colour reconstruction of underwater images [PDF]
, 2017 Objects look very different in the underwater environment compared to their appearance in sunlight. Images with correct colouring simplify the detection of underwater objects and may allow the use of visual SLAM algorithms developed for land-based robots
Wojciech Kowalczyk +3 more
core +1 more source
Advanced Science, EarlyView.Recent advances in metasurface‐enabled low‐observable technologies are reviewed from the perspective of cross‐scale material–structure synergy. Electromagnetic, thermal, optical, and acoustic stealth are highlighted together with dynamic tuning, programmable coding, data‐driven inverse design, artificial intelligence, multispectral compatibility, and ...
Shuhao Wang +5 more
wiley +1 more source
Environmental Model-Based Time-Reversal Underwater Communications
IEEE Access, 2018 This paper addresses channel compensation in underwater acoustic communications by proposing a method for inserting physical propagation modeling into a passive time-reversal (PTR) receiver.
Lussac P. Maia +2 more
doaj +1 more source
On Channel Codes for Short Underwater Messages
Information, 2020 Acoustic underwater communication is a challenging task. For a reliable transmission, not only good channel estimation and equalization, but also strong error correcting codes are needed.
Melanie Falk, Gerhard Bauch, Ivor Nissen
doaj +1 more source
Covert underwater acoustic communications
The Journal of the Acoustical Society of America, 2010 Low probability of detection (LPD) communications are conducted at a low received signal-to-noise ratio (SNR) to deter eavesdroppers to sense the presence of the transmitted signal. Successful detection at intended receiver heavily relies on the processing gain achieved by employing the direct-sequence spread-spectrum (DSSS) technique.
Jun Ling +4 more
openaire +2 more sources
Channel modeling for underwater optical communication [PDF]
2011 IEEE GLOBECOM Workshops (GC Wkshps), 2011 We consider in this paper channel modeling for underwater optical channels. In particular, we focus on the channel impulse response and quantify the channel time dispersion under different conditions of water type, link distance, and transmitter/receiver parameters.
Chadi Gabriel +4 more
openaire +4 more sources