Title :
Directional wavelet transform in the context of complex quadrature Doppler signals
Author :
Aydin, Nizamettin ; Markus, Hugh S.
Author_Institution :
Div. of Clinical Neurosci., St. Georges Hosp. Med. Sch., London, UK
Abstract :
Most Doppler ultrasound systems employ quadrature demodulation techniques at the detection stage. The information concerning flow direction encoded in the phase relationship between in-phase and quadrature phase channels is not obvious at this stage. A method based on the utilization of complex wavelets and negative scales has been described. It eliminates the intermediate processing stages by mapping directional information in the scale domain.
Keywords :
Doppler effect; acoustic signal processing; biomedical ultrasonics; demodulation; medical signal processing; wavelet transforms; Doppler ultrasound systems; complex quadrature Doppler signals; directional information; directional wavelet transform; flow direction; in-phase channels; negative scales; phase relationship; quadrature demodulation techniques; quadrature phase channels; scale domain; Fourier transforms; Frequency domain analysis; RF signals; Signal analysis; Signal processing; Signal resolution; Time frequency analysis; Ultrasonic imaging; Wavelet analysis; Wavelet transforms;
Journal_Title :
Signal Processing Letters, IEEE
