Patent ID: 6186949
Filing Date: 2001-02-13
Classification: G01S,Y10S

Abstract:
An imaging system comprising:a transducer array having a multiplicity of transducer elements for transmitting wave energy centered at a fundamental frequency in response to electrical activation and for transducing returned wave energy into electrical signals;a transmitter coupled to said transducer array and programmed to activate a plurality of said transducer elements to transmit focused wave energy encoded with a transmit code during first and second transmit events for each of a multiplicity of transmit focal positions in each of a multiplicity of scan planes;a receiver programmed to respectively form first and second receive signals from electrical signals produced by said plurality of transducer elements subsequent to said first and second transmit events respectively for each of a multiplicity of scan lines in each of said scan planes;a wall filter programmed with first and second sets of filter coefficients to compress and bandpass first and second fundamental signal components of said first and second receive signals respectively and selectively pass frequencies corresponding to wave energy reflectors moving at a velocity above a predetermined threshold, said wall filter forming a respective flow signal derived at least in part from the compressed and bandpassed first and second fundamental signal components and the selectively passed frequencies for each of said scan lines in each of said scan planes;a memory for storing a respective set of flow signals for each of said scan planes to form a data volume;a computer programmed to generate imaging data representing a three-dimensional projection of said data volume having a controllable orientation onto an imaging plane by applying a projection transformation to said data volume; anda subsystem for displaying an image which is a function of said three-dimensional projection.