Method and apparatus for flow imaging using golay codes

An imaging system comprising:

• a transducer array comprising a multiplicity of transducer elements for transmitting wave energy in response to electrical activation and traducing 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 in four sequential transmits, said wave energy being encoded with a first Golay code of a Golay code pair during first and third transmits and being encoded with a second Golay code of said Golay code pair during second and fourth transmits;
• a receiver programmed to respectively form first through fourth receive signals from electrical signals supplied from said plurality of transducer elements subsequent to said first through fourth transmits respectively;
• a filter for filtering said first and second receive signals as a function of said first and second Golay codes respectively to form first and second filtered signals respectively, and for filtering said third and fourth receive signals as a function of said first and second Golay codes respectively to form third and fourth filtered signals respectively;
• a vector subtractor for subtracting a first set of filtered signals from a second set of filtered signals to form a flow signal, said first set comprising said first and second filtered signals and said second set comprising said third and fourth filtered signals;
• a vector summer for combining output signals produced by said vector subtractor;
• and
• a subsystem for displaying an image having an image portion which is a function of said flow signal.

An imaging system comprising:

• a transducer array comprising a multiplicity of transducer elements for transmitting wave energy in response to electrical activation and 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 in four sequential transmits, said wave energy being encoded with a first Golay code of a Golay code pair during first and third transmits and being encoded with a second Golay code of said Golay code pair during second and fourth transmits;
• a receiver programmed to respectively form first through fourth receive signals from electrical signals supplied from said plurality of transducer elements subsequent to said first through fourth transmits respectively;
• means for
• (a) filtering said first and second receive signals as a function of said first and second Golay codes respectively to form first and second filtered signals respectively,
• (b) filtering said third and fourth receive signals as a function of said first and second Golay codes respectively to form third and fourth filtered signals respectively, and
• (c) inverting one of first and second sets of filtered signals, said first set comprising said first and second filtered signals and said second set comprising said third and fourth filtered signals;
• means for vector summing said first through fourth filtered signals to form a flow signal;
• and
• a subsystem for displaying an image having an image portion which is a function of said flow signal.

An imaging system comprising;

• a transducer array comprising a multiplicity of transducer elements for transmitting wave energy in response to electrical activation and 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 in four sequential transmits, said wave energy being encoded with a first Golay code of a Golay code pair during first and third transmits and being encoded with a second Golay code of said Golay code pair during second and fourth transmits;
• a receiver programmed to respectively form first through fourth receive signals from electrical signals supplied from said plurality of transducer elements subsequent to said first through fourth transmits respectively;
• a wall filter for decoding said first and third receive signals as a function of said first Golay code to form first and third decoded signals respectively, decoding said second and fourth receive signals as a function of said second Golay code to form second and fourth decoded signals respectively, and wall-filtering said first through fourth decoded signals to form a flow signal;
• and
• a subsystem for displaying an image having an image portion which is a function of said flow signal.

An imaging system comprising:

• a transducer array comprising a multiplicity of transducer elements for transmitting wave energy in response to electrical activation and transducing returned wave energy into electrical signals;
• a display monitor for displaying an image having an image portion which is a function of a flow image signal;
• and
• a processor programmed to perform the following steps:
• (a) activating transducer elements of said array to transmit focused wave energy in four sequential transmits, said wave energy being encoded with a first Golay code of a Golay code pair during first and third transmits and being encoded with a second Golay code of said Golay code pair during second and fourth transmits;
• (b) forming first through fourth receive signals from electrical signals supplied from said plurality of transducer elements subsequent to said first through fourth transmits respectively;
• (c) filtering said first and third receive signals as a function of said first Golay code to form first and third filtered signals respectively;
• (d) filtering said second and fourth receive signals as a function of said second Golay code to form second and fourth filtered signals respectively;
• (e) wall-filtering said first through fourth filtered signals to form a flow signal;
• (f) forming a flow image signal derived at least in part from said flow signal;
• and
• (g) applying said flow image signal to said display monitor.

An imaging method comprising the steps of:

• transmitting focused wave energy in four sequential transmits, said wave energy being encoded with a first Golay code of a Golay code pair during first and third transmits and with a second Golay code of said Golay code pair during second and fourth transmits;
• forming first through fourth receive signals derived from echo signals detected subsequent to said first through fourth transmits respectively;
• filtering said first and third receive signals as a function of said first Golay code to form first and third filtered signals respectively;
• filtering said second and fourth receive signals as a function of said second Golay code to form second and fourth filtered signals respectively;
• wall-filtering said first through fourth filtered signals to form a flow signal;
• and
• displaying an image having an image portion which is a function of said flow signal.

An imaging system comprising:

• a transducer array comprising a multiplicity of transducer elements for transmitting wave energy in response to electrical activation and 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 in four sequential transmits, said wave energy being encoded with a first Golay code of a Golay code pair during first and fourth transmits and being encoded with a second Golay code of said Golay code pair during second and third transmits;
• a receiver programmed to respectively form first through fourth receive signals from electrical signals supplied from said plurality of transducer elements subsequent to said first through fourth transmits respectively;
• a wall filter for decoding said first and fourth receive signals as a function of said first Golay code to form first and fourth decoded signals respectively, decoding said second and third receive signals as a function of said second Golay code to form second and third decoded signals respectively, and wall-filtering said first through fourth decoded signals to form a flow signal;
• and
• a subsystem for displaying an image having an image portion which is a function of said flow signal.

An imaging system comprising:

• a transducer array comprising a multiplicity of transducer elements for transmitting wave energy in response to electrical activation and transducing returned wave energy into electrical signals;
• a display monitor for displaying an image having an image portion which is a function of a flow image signal;
• and
• a processor programmed to perform the following steps:
• (a) activating transducer elements of said array to transmit focused wave energy in four sequential transmits, said wave energy being encoded with a first Golay code of a Golay code pair during first and fourth transmits and being encoded with a second Golay code of said Golay code pair during second and third transmits;
• (b) forming first through fourth receive signals from electrical signals supplied from said plurality of transducer elements subsequent to said first through fourth transmits respectively;
• (c) filtering said first and fourth receive signals as a function of said first Golay code and a predetermined factor to form first and fourth filtered signals respectively;
• (d) filtering said second and third receive signals as a function of said second Golay code to form second and third filtered signals respectively;
• (e) wall-filtering said first through fourth filtered signals to form a flow signal;
• (f) forming a flow image signal derived at least in part from said flow signal;
• and
• (g) applying said flow image signal to said display monitor.

An imaging method comprising the steps of:

• transmitting focused wave energy in four sequential transmits, said wave energy being encoded with a first Golay code of a Golay code pair during first and fourth transmits and with a second Golay code of said Golay code pair during second and third transmits;
• forming first through fourth receive signals derived from echo signals detected subsequent to said first through fourth transmits respectively;
• filtering said first and fourth receive signals as a function of said first Golay code and a predetermined factor to form first and fourth filtered signals respectively;
• filtering said second and third receive signals as a function of said second Golay code to form second and third filtered signals respectively;
• wall-filtering said first through fourth filtered signals to form a flow signal;
• and
• displaying an image having an image portion which is a function of a flow image signal.