Large dynamic range time-frequency signal analysis with application to helicopter Doppler radar data

AbstractSingle-Doppler radar data are often missing in important regions of a severe storm due to low return power, low signal-to-noise ratio, ground clutter associated with normal and anomalous propagation, and missing radials associated with partial or total beam blockage. Missing data impact the ability of WSR-88D algorithms to detect severe weather. To aid the algorithms, we develop a variational technique that fills in Doppler velocity data voids smoothly by minimizing Doppler velocity gradients while not modifying good data. This method provides estimates of the analysed variable in data voids without creating extrema.Actual single-Doppler radar data of four tornadoes are used to demonstrate the variational algorithm. In two cases, data are missing in the original data, and in the other two, data are voided artificially. The filled-in data match the voided data well in smoothly varying Doppler velocity fields. Near singularities such as tornadic vortex signatures, the match is poor as anticipated. The algorithm does not create any velocity peaks in the former data voids, thus preventing false triggering of tornado warnings. Doppler circulation is used herein as a far-field tornado detection and advance-warning parameter. In almost all cases, the measured circulation is quite insensitive to the data that have been voided and then filled. The tornado threat is still apparent.

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EEG spike detection using time-frequency signal analysis

2004 IEEE International Conference on Acoustics, Speech, and Signal Processing ◽

10.1109/icassp.2004.1327137 ◽

2004 ◽

Cited By ~ 11

Author(s):

H. Hassanpour ◽

M. Mesbah ◽

B. Boashash

Keyword(s):

Signal Analysis ◽

Spike Detection ◽

Frequency Signal ◽

Time Frequency

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An architecture for the realization of a system for time-frequency signal analysis

IEEE Transactions on Circuits and Systems II Analog and Digital Signal Processing ◽

10.1109/82.598433 ◽

1997 ◽

Vol 44 (7) ◽

pp. 600-604 ◽

Cited By ~ 36

Author(s):

S. Stankovic ◽

L. Stankovic

Keyword(s):

Signal Analysis ◽

Frequency Signal ◽

Time Frequency

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Retrieval of three-dimensional wind fields from Doppler radar data using an efficient two-step approach

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-3-4459-2010 ◽

2010 ◽

Vol 3 (5) ◽

pp. 4459-4495 ◽

Cited By ~ 1

Author(s):

C. López Carrillo ◽

D. J. Raymond

Keyword(s):

Variational Approach ◽

Continuity Equation ◽

Doppler Radar ◽

Three Dimensional ◽

Relevant Information ◽

Radar Data ◽

Wind Fields ◽

Wind Retrieval ◽

Complex Sampling ◽

Doppler Radar Data

Abstract. In this work, we describe an efficient approach for wind retrieval from dual Doppler radar data. The approach produces a gridded field that not only satisfies the observations, but also satisfies the anelastic mass continuity equation. The method is based on the so-called three-dimensional variational approach to the retrieval of wind fields from radar data. The novelty consists in separating the task into steps that reduce the amount of data processed by the global minimization algorithm, while keeping the most relevant information from the radar observations. The method is flexible enough to incorporate observations from several radars, accommodate complex sampling geometries, and readily include dropsonde or sounding observations in the analysis. We demonstrate the usefulness of our method by analyzing a real case with data collected during the TPARC/TCS-08 field campaign.

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