Results 31 to 40 of about 519,750 (303)
Flow angle dependence for the asymmetry of broad 50-MHz coherent echoes at large magnetic aspect angles [PDF]
, 1997 International audienceThe skewness of broad Type 2-like spectra has been studied using data collected by two orthogonal CW 50-MHz radio links with co-located scattering volumes. Geometrical aspect angles of observations were about 10°.
Sofko, G.J. +11 more
core +2 more sources
High-latitude HF Doppler observations of ULF waves: 2. Waves with small spatial scale sizes [PDF]
Annales Geophysicae, 1999 The DOPE (Doppler Pulsation Experiment) HF Doppler sounder located near Tromsø, Norway (geographic: 69.6°N 19.2°E; L = 6.3) is deployed to observe signatures, in the high-latitude ionosphere, of magnetospheric ULF waves.
D. M. Wright, T. K. Yeoman
doaj +1 more source
Acousto-optic frequency switching for single-camera planar Doppler velocimetry [PDF]
, 2001 A single-camera Planar Doppler velocimetry system has been demonstrated, in which illumination beams at two closely-spaced optical frequencies are derived from a single Argon-ion laser.
Nobes, David S. +5 more
core +1 more source
Single camera three component planar velocity measurements, using two frequency Planar Doppler Velocimetry (2v-PDV) (2005) [PDF]
, 2005 The work presented here describes a method that allows three component velocity measurements to be made, quickly and non-intrusively, across a plane in a flow defined by a laser light sheet. The method, two frequency planar Doppler Velocimetry (2v-PDV)
Charrett, Thomas O. H. +5 more
core +1 more source
IEEE Access, 2022 Classification of multiple drones and birds by comparing micro-Doppler (MD) signatures is a very difficult task because the MD signatures of multiple birds can contaminate the MD signature of drones, and because a single drone can yield a very similar MD
Sewon Yoon +7 more
doaj +1 more source
High-latitude observations of impulse-driven ULF pulsations in the ionosphere and on the ground [PDF]
, 2003 International audienceWe report the simultaneous observation of 1.6?1.7 mHz pulsations in the ionospheric F-region with the CUTLASS bistatic HF radar and an HF Doppler sounder, on the ground with the IMAGE and SAMNET magnetometer arrays, and in the ...
Menk, F. W. +14 more
core +2 more sources
Remote Sensing, 2022 Remote sensing techniques in the microwave frequency range have been successfully used in the context of bird, bat and insect measurements. This article breaks new ground in the analysis of freely flying insects by using a continuous-wave (CW) radar ...
Murat Diyap +3 more
doaj +1 more source
Ultrasonic Doppler methods to extract signatures of a walking human [PDF]
The Journal of the Acoustical Society of America, 2012 Extraction of Doppler signatures that characterize human motion has attracted a growing interest in recent years. These Doppler signatures are generated by various components of the human body while walking, and contain unique features that can be used for human detection and recognition.
Asif, Mehmood +2 more
openaire +2 more sources
Three-dimensional reconstruction of space rotating target based on narrow-band radar networks
The Journal of Engineering, 2019 The micro-motion of space target is an important signature for classification and recognition, which has received great attention. Based on the micro-Doppler signals from narrow-band radar networks, this study proposes a three-dimensional reconstruction ...
Chao Wang, Shu L. Wen, Chun M. Ye
doaj +1 more source
Examination of Drone Micro-Doppler and JEM/HERM Signatures [PDF]
2020 IEEE Radar Conference (RadarConf20), 2020 Radars monitoring small targets often must increase their integration times to achieve sufficient signal-to-noise ratio (SNR) for maintaining a viable track. These longer integation times can prevent micro-Doppler signature extraction and instead result in Doppler signatures consisting of spectral lines to the radar's higher-level processing.
Markow, John, Balleri, Alessio
openaire +2 more sources