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Multigate doppler signal analysis using 3-D regularized long AR modelling.

C Berthomier·A Herment·J F Giovannelli·G Guidi·L Pourcelot·B Diebold
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Abstract

Autoregressive (AR) modelling has already been proposed as an alternative to fast Fourier transform to process ultrasound (US) Doppler signals. Previous works introduced long AR models, set up under a regularization framework. The latter may be in 1-D (frequency) or 2-D (frequency and space or time). This study generalizes the spectrum regularization in the three dimensions frequency, space and time. The problem of the penalization function is addressed, and a new convex solution is proposed, taking into account possible nonstationarity of the Doppler signal. The parameter tuning is based on simulations using a standard Doppler signal model. The first results show that this processing improves the spectral estimation, and is well suited to flow interpretation.

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AlgorithmsCarotid ArteriesFourier AnalysisHeartHumansModels, TheoreticalSignal Processing, Computer-AssistedUltrasonography, DopplerJournal Article

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BibTeXRIS

C Berthomier, A Herment, J F Giovannelli, G Guidi, L Pourcelot, B Diebold. 2001. Multigate doppler signal analysis using 3-D regularized long AR modelling.. https://doi.org/10.1016/s0301-5629(01)00446-x

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