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Doppler Velocity Log (DVL) navigation for observation-class ROVs
OCEANS 2010 MTS/IEEE SEATTLE, 2010Doppler Velocity Logs (DVLs) have become increasingly popular as navigation tools on remotely-operated vehicles, autonomous underwater vehicles, and human-occupied vehicles for over a decade. Using acoustic measurements to capture bottom tracking velocity measurements, DVLs can provide updated velocities which can in turn be used to calculate distance ...
Jeffrey Z. Snyder
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Wind velocity observation with a CW Doppler radar
IEEE Transactions on Geoscience and Remote Sensing, 2002We study the problem of gathering information about wind velocity from continuous-wave clear-air Doppler radar measurements. The radar is assumed to be a monostatic fixed-frequency Doppler radar, and the wind velocity as well as the reflectivity are modeled as random fields with statistical parameters depending on the altitude.
M. Lassas +3 more
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Doppler pressure field deduced from the doppler velocity field in an observation plane in a fluid
Ultrasound in Medicine & Biology, 2003A new method is developed for a nondisturbing and quantitative measurement of the pressure at an arbitrary point in a flowing fluid in three-dimensional (3-D) space. In this method, after measuring the velocity field in the observation plane (scanning plane) using the pulsed Doppler technique, the velocity component orthogonal to the Doppler velocity ...
Shigeo, Ohtsuki, Motonao, Tanaka
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A study of GPS PPP velocity estimation with the constraints of Doppler observation
Advances in Space Research, 2020Abstract Precise Point Positioning Velocity Estimation (PPPVE) and Doppler Velocity Estimation (DVE) are two commonly used methods for precise velocity estimation with a stand-alone GPS receiver. The accuracy of PPPVE is affected by the dynamic model and the dynamic conditions of the vehicle, while the motion state of the vehicle has little influence
Xingxing Wang +5 more
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Physical Review A, 2011
We observed an electromagnetically induced transparency signal in a four-level system with optically selected rubidium atoms at specific velocities in a room-temperature vaporized cell. Since the atoms behave like cold atoms in the selected atomic view, the observed signals coincide with a trapped atomic system. According to this result, we can observe
Hoon Yu +4 more
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We observed an electromagnetically induced transparency signal in a four-level system with optically selected rubidium atoms at specific velocities in a room-temperature vaporized cell. Since the atoms behave like cold atoms in the selected atomic view, the observed signals coincide with a trapped atomic system. According to this result, we can observe
Hoon Yu +4 more
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Improved velocity estimation in urban areas using Doppler observations
2021 International Conference on Localization and GNSS (ICL-GNSS), 2021In urban areas, Global navigation satellite system (GNSS) velocity estimation suffers due to signal obstruction and multipath effects. This paper explores two different variance models, known as elevation dependent and SIGMA-e to account for the different quality of the Doppler observations accurately in an urban surrounding.
Ankit Jain +2 more
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I-Channel FMCW Doppler Radar for Long-Range and High-Velocity Targets
IEEE Geoscience and Remote Sensing Letters, 2021Frequency-modulated continuous-wave (FMCW) radar is known for distance and velocity measurements of close and slow targets, i.e., targets with round-trip delays much shorter and Doppler periods much longer than the chirp repetition period.
T. Casademont +3 more
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Chromaticity-coded doppler blood velocity sonagrams: Preliminary observations
Ultrasound in Medicine & Biology, 1988This paper describes the application of chromaticity to spectrally analysed Doppler blood velocity signals. Chromaticity enables a particular colour to be assigned to the power/frequency distribution within each instantaneous spectral sweep of a sonagram.
S, Kontis, T S, Padayachee, R G, Gosling
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Minimum Detectable Velocity Based on GNSS Doppler Phase Observables
2018 European Navigation Conference (ENC), 2018A focus of the Institute for Geodesy and Photogrammetry (IGP) lies on the GNSS data processing for the monitoring of slope movements in high Alpine regions in the Swiss Alps. Thawning of permafrost areas (e.g. rock glaciers) can cause threats for humans and infrastructure.
Roland Hohensinn +2 more
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