Traitement d'antenne adaptatif robuste appliqué à l'imagerie passive de la cavitation

L'imagerie ultrasonore passive de la cavitation est essentielle pour le controle de la therapie ultrasonore. La methode de reconstruction d'image conventionnelle souffre d'une mauvaise resolution ne localisant pas toujours precisement les bulles de cavitation. De plus, elle opere dans le domaine temporel : l'analyse frequentielle des signaux recus est limitee, pourtant tres utile a l'identification des differents regimes de cavitation. Afin de pallier ces limitations, la methode adaptative robuste de Capon dans le domaine de Fourier est adaptee a l'imagerie passive de la cavitation. La methode est evaluee en simulation sur des modeles de cavitation stable et inertielle. Abstract-The passive acoustic imaging of cavitation is essential for the control of the ultrasound therapy. The conventional image reconstruction method suffers from a poor resolution which hinders the precise localization of the cavitation bubbles. Moreover, since it operates in the time domain, it does not allow the frequency analysis of the received signals, yet required for the identification of the cavitation regimes. To overcome these limitations, the robust adaptive Capon's method in the Fourier domain is adapted to passive cavitation imaging. The method is evaluated in simulation on stable and inertial cavitation models.