Results 1 to 10 of about 26,178 (269)
Detection of Low RCS Unmanned Air Systems Using K-Band Continuous Wave Doppler Radar
Journal of Electrical and Computer Engineering, 2023 UASs (Unmanned Air Systems) are universally used in many activities, spanning from leisure-commercial to military applications. Accordingly, as the number of UASs operating in the sky increases, so does the need to detect and identify them, in order to ...
Alexandros Kyritsis +2 more
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IEEE Photonics Journal, 2022 This paper comprehensively investigated noise characteristics of superluminal propagation based on low-noise single-frequency Brillouin lasing oscillation with the aid of a population inversion dynamic grating.
Liang Zhang +6 more
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Deep learning–based vortex decomposition and switching based on fiber vector eigenmodes
Nanophotonics, 2023 Structured optical fields, such as cylindrical vector (CV) and orbital angular momentum (OAM) modes, have attracted considerable attention due to their polarization singularities and helical phase wavefront structure.
Hou Mengdie +9 more
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IEEE Photonics Journal, 2021 In this paper, a microfiber knot resonator (MKR) was encapsulated in polydimethylsiloxane (PDMS), and its capability to sense temperature was experimentally evaluated.
Hongtao Dang, Mingshu Chen, Jin Li
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Small UAS Online Audio DOA Estimation and Real-Time Identification Using Machine Learning
Sensors, 2022 The wide range of unmanned aerial system (UAS) applications has led to a substantial increase in their numbers, giving rise to a whole new area of systems aiming at detecting and/or mitigating their potentially unauthorized activities.
Alexandros Kyritsis +2 more
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IEEE Photonics Journal, 2022 A fiber-optic accelerometer based on extrinsic Fabry-Perot interferometer (EFPI) is reported. The sensor adopts flywheel diaphragm structure as a sensitive element, where the mass block is bonded in the center, while the beam of the flywheel acts as a ...
Peng Zhang +5 more
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Fiber Optic Sensors for Harsh and High Radiation Environments in Aerospace Applications
Sensors, 2023 In the upcoming space revolutions aiming at the implementation of automated, smart, and self-aware crewless vehicles and reusable spacecraft, sensors play a significant role in the control systems.
Alberto Rovera +5 more
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Active and Passive Electronic Components, 2002 In this paper a MMIC QPSK modulator is described. The bit rate of the baseband signal is 155 Mbits/sec, while the frequency of the carrier is fLO=10 GHz . The modulation is performed directly at the RF band and therefore an IF stage is not necessary. The
Petros S. Tsenes +3 more
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Active and Passive Electronic Components, 2002 In this paper two active MMIC mixers for RF front-end applications are described. A down-converter that converts an RF signal (fRF=10.45 GHz) into an IF signal (fIF=0.95 GHz) using an LO signal (fLO=9.5 GHz) and an up-converter that performs the ...
Ptros S. Tsenes +2 more
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Rare Earth Doped Optical Fibers with Multi-section Core
iScience, 2019 Summary: The gain bandwidth of a single-mode fiber is limited by the atomic transitions of one rare earth gain element. Here we overcome this long-standing challenge by designing a new single-mode fiber with multi-section core, where each section is ...
Chongyuan Huang +7 more
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