Signal and Image Restoration |
MembersProject description
One of the major limitation on US image quality is reduced resolution due to both the effect of limited effective aperture size and noise.
Moreover, since the US transducer pulse ntroduces an unwanted spectral shaping of the backscattered echo signal, econvolution is used to
eliminate this effect and to obtain the pure tissue esponse. Due to the electromechanical properties of the crystals, the geometry of the system, the focusing used in the imaging process, and the frequency dependant attenuation opposed by the tissue, the transduceres response, i.e. the channel, is highly non-stationary and needs to be estimated.In our research group we implemented algorithms for minimum and non-minimum phase, mono and bidimensional channel estimation, performing the non trivial task of phase unwrapping within a bayesian framework. Spatial variations of the channel are tracked by coupling the Viterbi algorithm with adaptive-filtering techniques.
Collaborations |