Velocity despiking: Difference between revisions
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== Overview == | == Overview == | ||
Any measured signal may be contaminated by spikes. These spikes are typically short-lived and transient, which result in sudden change in the measured signal. | |||
<ref name="GoringNikora">{{Cite journal|authors= D. G. Goring and V.I. Nikora|journal_or_publisher= Journal of Hydraulic Engineering|paper_or_booktitle= Despiking Acoustic Doppler Velocimeter Data | |||
|year= 2002|doi= 10.1061/ASCE0733-94292002128:1117}}</ref> | Spikes in velocities measured by [[Acoustic-Doppler Velocimeters| acoustic-Doppler velocimeters]] can result from aliasing of the Doppler signal, in particular when pulses become contaminated by reflecting from complex objects and boundaries <ref name="GoringNikora">{{Cite journal|authors= D. G. Goring and V.I. Nikora|journal_or_publisher= Journal of Hydraulic Engineering|paper_or_booktitle= Despiking Acoustic Doppler Velocimeter Data | ||
|year= 2002|doi= 10.1061/ASCE0733-94292002128:1117}}</ref>. Several techniques exist for de-spiking. | |||
[[File:Velocities spike.png|thumb|Example velocities measured by an [[Acoustic-Doppler Velocimeters| acoustic-Doppler velocimeters]].]] | |||
The most used with [[Acoustic-Doppler Velocimeters| acoustic-Doppler velocimeters]] are the phase-space thresholding techniques <ref name="GoringNikora"\>. | |||
Other techniques currently being investigated by the subgroup are those used in atmospheric turbulence studies | Other techniques currently being investigated by the subgroup are those used in atmospheric turbulence studies | ||
<ref name="Starkenburg">{{Cite journal|authors= D. Starkenburg, S. Metzger, G.J. Fochesatto, J.G Alfieri, R. Gens, A. Prakash and J. Cristobal|journal_or_publisher= J. Atmos. Oceanic Technoly|paper_or_booktitle= Assessment of Despiking Methods for Turbulence Data in Micrometeorology | <ref name="Starkenburg">{{Cite journal|authors= D. Starkenburg, S. Metzger, G.J. Fochesatto, J.G Alfieri, R. Gens, A. Prakash and J. Cristobal|journal_or_publisher= J. Atmos. Oceanic Technoly|paper_or_booktitle= Assessment of Despiking Methods for Turbulence Data in Micrometeorology | ||
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==Notes== | ==Notes== | ||
Revision as of 18:37, 24 November 2021
Overview
Any measured signal may be contaminated by spikes. These spikes are typically short-lived and transient, which result in sudden change in the measured signal.
Spikes in velocities measured by acoustic-Doppler velocimeters can result from aliasing of the Doppler signal, in particular when pulses become contaminated by reflecting from complex objects and boundaries [1]. Several techniques exist for de-spiking.
The most used with acoustic-Doppler velocimeters are the phase-space thresholding techniques Cite error: Closing </ref> missing for <ref> tag, in particular median filter despiking technique [2].
Notes
- ↑ D. G. Goring and V.I. Nikora. 2002. Despiking Acoustic Doppler Velocimeter Data. Journal of Hydraulic Engineering. doi:10.1061/ASCE0733-94292002128:1117
- ↑ F.V. Brock. 1986. A nonlinear filter to remove impulse noise from meteorological data. J. Atmos. Oceanic Technoly. doi:10.1175/1520-0426(1986)003,0051:ANFTRI.2.0.CO;2
