Results 91 to 100 of about 11,441 (205)

Evaluating SWOT in the Coastal Zone: Comparisons With Tide Gauge and Airborne LiDAR in the Bristol Channel and Severn Estuary, UK

Geophysical Research Letters, Volume 53, Issue 2, 28 January 2026.
Abstract Traditional nadir altimeters struggle with coastal water surface elevation (WSE) measurement and fine‐scale river‐estuary interactions, due to land‐water signal interference and their wide inter‐track spacing. The wide‐swath Surface Water and Ocean Topography (SWOT) mission, using a new Ka‐band radar interferometer, aims to address these ...
Youtong Rong, Paul Bates, Jeff Neal, Paul Bell, Christine Gommenginger, Ian Dougal Lichtman, Christopher Banks, Francisco J. M. Calafat, Adrien Martin, Jennifer Brown, Richard Cooke, Christopher Balfour, Michela De Dominicis, Marta Payo Payo, Simon Williams, Laurent Amoudry, Stephen Chuter, Simon Neill, Jude Chisholm, Colin J. Gleason, John Kupiec, Matt Lewis   +21 more
wiley   +1 more source

Near‐Field Optical Detection of Defect‐Stabilized Metallic Islands at the Verwey Transition in Fe3O4

Advanced Functional Materials, Volume 36, Issue 1, 2 January 2026.
Nanoscale metallic islands emerging across the Verwey transition in thin films of Fe3O4 are imaged using near‐field optical microscopy from mid‐infrared to terahertz frequencies. Recurring across thermal cycles, these disorder‐stabilized islands exhibit distinct transition temperatures.
Kajal Tiwari, Mostafa Ibrahim Shehata Marzouk, Ke Xiao, Malleswararao Tangi, Stuart Stephen Papworth Parkin   +4 more
wiley   +1 more source

Distributed Fiber-Optic Sensor for Detection and Localization of Acoustic Vibrations

Metrology and Measurement Systems, 2015
A sensing system utilizing a standard optical fiber as a distributed sensor for the detection and localization of mechanical vibrations is presented.
Sifta Radim, Munster Petr, Sysel Petr, Horvath Tomas, Novotny Vit, Krajsa Ondrej, Filka Miloslav   +6 more
doaj   +1 more source

Quadratic Time-Frequency Transforms-Based Brillouin Optical Time-Domain Reflectometry

IEEE Sensors Journal, 2017
Linear and quadratic Time-Frequency (T-F) transforms are proposed for the signal processing of the Brillouin optical time-domain reflectometry, to improve the system performance, in terms of the transition responsivity and frequency resolution.
Yu, Yifei, Luo, Linqing, Bo, Li, Soga, Kenichi, Yan, Jize   +4 more
openaire   +4 more sources

Optical time domain reflectometry by photon counting

Electronics Letters, 1980
A photon counting technique has been used to extend greatly the range of optical time domain reflectometry or `back-scatter? for fault location in optical fibre systems. A range of more than 40 dB of one-way fibre loss has been achieved even when the break was index-matched to eliminate any reflection.
P. Healey, P. Hensel
openaire   +1 more source

Hybrid Coding Technique for Pulse Detection in an Optical Time Domain Reflectometer [PDF]

, 2012
The paper introduces a novel hybrid coding technique for improved pulse detection in an optical time domain reflectometer. The hybrid schemes combines Simplex codes with signal averaging to articulate a very sophisticated coding technique that ...
Abbas, A., Mehmood, H., Naseem, A., Sheikh Muhammad, S.   +3 more
core   +1 more source

Signal to Noise Ratio (SNR) Enhancement Comparison of Impulse-, Coding- and Novel Linear-Frequency-Chirp-Based Optical Time Domain Reflectometry (OTDR) for Passive Optical Network (PON) Monitoring Based on Unique Combinations of Wavelength Selective Mirrors

Photonics, 2014
We compare optical time domain reflectometry (OTDR) techniques based on conventional single impulse, coding and linear frequency chirps concerning their signal to noise ratio (SNR) enhancements by measurements in a passive optical network (PON) with a ...
Christopher M. Bentz, Lars Baudzus, Peter M. Krummrich   +2 more
doaj   +1 more source

Temporal Depolarization Suppressed POTDR System for Quasi-Distributed Instantaneous Intrusion Sensing and Vibration Frequency Measurement

IEEE Photonics Journal, 2016
Theoretical investigation on the mechanism of temporal depolarization effect in a polarization optical time-domain reflectometry (POTDR) system is conducted.
Chaodong Wang, Yaling Zhou, Hao Wu, Can Zhao, Jianguan Tang, Ciming Zhou, Songnian Fu, Ping Shum, Ming Tang   +8 more
doaj   +1 more source

SiPM used as fast Photon-Counting Module and for Multiphoton Detection

, 2007
We demonstrate fast counting and multiphoton detection abilities of a Silicon Photo Multiplier (SiPM). In fast counting mode we are able to detect two consecutive photons separated by only 2.3 ns corresponding to 430 MHz.
Eraerds, P., Gisin, N., Legre, M., Rochas, A., Zbinden, H.   +4 more
core   +2 more sources

Channel Capacity of Wavelength Division Multiplexing-Based Brillouin Optical Time Domain Sensors

IEEE Photonics Journal, 2018
We propose and demonstrate a novel WDM-based Brillouin optical time domain analysis (BOTDA) sensor using Brillouin loss configuration, and theoretically analyze channel capacity of WDM-based brillouin optical time domain reflectometry (BOTDR) and BOTDA ...
Zelin Zhang, Yuangang Lu, Yunqin Zhao
doaj   +1 more source