ISSN:
1741-0444
Schlagwort(e):
Autoregressive modelling
;
Fourier transform
;
Maximum likelhood method
;
Spectrum analysis
;
Ultrasonic Doppler signal
;
Velocity distribution
;
Wigner-Ville distribution
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Biologie
,
Chemie und Pharmazie
,
Medizin
Notizen:
Abstract The direct Fourier transform method, autoregressive modelling, the maximum likelihood method and the Wigner-Ville distribution were applied to the Doppler signal obtained from a fully insonated laminar model flow. The appreciation of the spectral method was based on the properties of the ratio variance/(fmean)2 (INT) of the spectrum. The basic criterion was the sensitivity of INT to the analysis parameters, especially the data window. The results of spectral analysis, as well as the properties of INT, were strongly affected by the method applied. The maximum likelihood method appeared best suited for the purpose of assessment of velocity distribution and is expected to give the best results in the case of in vivo blood flow. The performances of other discussed methods were inferior, due to their stronger incompatibility with the signal properties.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF02441462
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