Beamforming methods and apparatus for three-dimensional ultrasound imaging using two-dimensional transducer array

An ultrasound transducer assembly for use in an ultrasound imaging system, comprising:

• a transducer handle containing a two-dimensional array of ultrasound transducer elements that define a plurality of subarrays, and a subarray processor associated with each of said subarrays, each subarray processor comprising receive circuitry, responsive to transducer signals generated by receive elements of the associated subarray in response to received ultrasound energy, wherein the receive elements of the associated subarray are distributed in at least two dimensions on said two-dimensional array, said receive circuitry providing first and second subarray signals, said first subarray signal comprising a sum of first weighted component signals and said second subarray signal comprising a sum of second weighted component signals, said first and second component signals being derived from the respective transducer signals;
• a transducer connector for connecting the transducer assembly to an electronics unit of the ultrasound imaging system, said connector including a housing containing a phase shift network associated with each of said subarrays for phase shifting and combining said first and second subarray signals to provide a phase shifted subarray signal;
• and
• a transducer cable interconnecting said handle and said connector.

An ultrasound imaging system comprising:

• a two-dimensional array of ultrasound transducer elements that define a plurality of subarrays;
• a transmitter for transmitting ultrasound energy into a region of interest along a desired scan line in a three-dimensional space with transmit elements of the array;
• a subarray processor associated with each of said subarrays, each subarray processor comprising receive circuitry, responsive to transducer signals generated by receive elements of the associated subarray in response to ultrasound energy received from said region of interest, wherein the receive elements of the associated subarray are distributed in at least two dimensions on said two-dimensional array, said receive circuitry providing first and second subarray signals, said first subarray signal comprising a sum of first weighted component signals and said second subarray signal comprising a sum of second weighted component signals, said first and second component signals being derived from the respective transducer signals;
• a phase shift network associated with each of said subarrays for phase shifting and combining said first and second subarray signals to provide a phase shifted subarray signal;
• a primary beamformer comprising a delay circuit associated with each of said subarrays for delaying said phase shifted subarray signals by delays that are individually controlled and providing delayed subarray signals, and a summing circuit for summing said delayed subarray signals and providing a beamformer signal;
• and
• an image generating circuit responsive to said beamformer signal for generating an image of the region of interest.

An ultrasound imaging system comprising:

• a two-dimensional array of ultrasound transducer elements that define a plurality of subarrays:
• a transmitter for transmitting ultrasound energy into a region of interest along a desired scan line in a three-dimensional space with transmit elements of the array;
• a subarray processor associated with each of said subarrays, each subarray processor comprising receive circuitry, responsive to transducer signals generated by receive elements of the associated subarray in response to ultrasound energy received from said region of interest, for providing first and second subarray signals, said first subarray signal comprising a sum of first weighted component signals and said second subarray signal comprising a sum of second weighted component signals, said first and second component signals being derived from the respective transducer signals;
• a phase shift network associated with each of said subarrays for phase shifting and combining said first and second subarray signals to provide a phase shifted subarray signal;
• a primary beamformer comprising a delay circuit associated with each of said subarrays for delaying said phase shifted subarray signals by delays that are individually controlled and providing delayed subarray signals, and a summing circuit for summing said delayed subarray signals and providing a beamformer signal;
• and
• an image generating circuit responsive to said beamformer signal for generating an image of the region of interest, said imaging system comprising a transducer assembly and an electronics unit, said transducer assembly comprising a transducer handle containing said array of transducer elements and said subarray processors, a transducer connector for connecting said transducer assembly to said electronics unit and a transducer cable interconnecting said transducer handle and said transducer connector, wherein said phase shift networks are located in said transducer connector.

An ultrasound imaging system comprising:

• a two-dimensional array of ultrasound transducer elements that define a plurality of subarrays;
• a transmitter for transmitting ultrasound energy into a region of interest along a desired scan line in a three-dimensional space with transmit elements of the array;
• a subarray processor associated with each of said subarrays, each subarray processor comprising receive circuitry, responsive to transducer signals generated by receive elements of the associated subarray in response to ultrasound energy received from said region of interest, for providing first and second subarray signals, said first subarray signal comprising a sum of first weighted component signals and said second subarray signal comprising a sum of second weighted component signals, said first and second component signals being derived from the respective transducer signals;
• a phase shift network associated with each of said subarrays for phase shifting and combining said first and second subarray signals to provide a phase shifted subarray signal;
• a primary beamformer comprising a delay circuit associated with each of said subarrays for delaying said phase shifted subarray signals by delays that are individually controlled and providing delayed subarray signals, and a summing circuit for summing said delayed subarray signals and providing a beamformer signal;
• and
• an image generating circuit responsive to said beamformer signal for generating an image of the region of interest, said imaging system comprising a transducer assembly and an electronics unit, said transducer assembly comprising a transducer handle containing said array of transducer elements and said subarray processors, a transducer connector for connecting said transducer assembly to said electronics unit and a transducer cable interconnecting said transducer handle and said transducer connector, wherein said phase shift networks are located in said electronics unit.

An ultrasound imaging system comprising:

• a two-dimensional array of ultrasound transducer elements that define a plurality of subarrays;
• a transmitter for transmitting ultrasound energy into a region of interest along a desired scan line in a three-dimensional space with transmit elements of the array;
• a subarray processor associated with each of said subarrays, each subarray processor comprising receive circuitry, responsive to transducer signals generated by receive elements of the associated subarray in response to ultrasound energy received from said region of interest, for providing first and second subarray signals, said first subarray signal comprising a sum of first weighted component signals and said second subarray signal comprising a sum of second weighted component signals, said first and second component signals being derived from the respective transducer signals;
• a phase shift network associated with each of said subarrays for phase shifting and combining said first and second subarray signals to provide a phase shifted subarray signal;
• a primary beamformer comprising a delay circuit associated with each of said subarrays for delaying said phase shifted subarray signals by delays that are individually controlled and providing delayed subarray signals, and a summing circuit for summing said delayed subarray signals and providing a beamformer signal;
• and
• an image generating circuit responsive to said beamformer signal for generating an image of the region of interest, said imaging system comprising a transducer assembly and an electronics unit, said transducer assembly comprising a transducer handle containing said array of transducer elements and said subarray processors, a transducer connector for connecting said transducer assembly to said electronics unit and a transducer cable interconnecting said transducer handle and said transducer connector, wherein said phase shift networks are located in said transducer handle.

An ultrasound imaging system comprising:

• a two-dimensional array of ultrasound transducer elements that define a plurality of subarrays;
• a transmitter for transmitting ultrasound energy into a region of interest along a desired scan line in a three-dimensional space with transmit elements of the array;
• a subarray processor associated with each of said subarrays, each subarray processor comprising receive circuitry, responsive to transducer signals received by receive elements of the associated subarray in response to ultrasound energy received from said region of interest, wherein the receive elements of the associated subarray are distributed in at least two dimensions on said two-dimensional array, said receive circuitry providing first and second subarray signals, said first subarray signal comprising a sum of first component signals and said second subarray signal comprising a sum of second component signals, said first and second component signals being derived from the respective transducer signals;
• a primary beamformer comprising first and second delay circuits associated with each of said subarrays for delaying said first and second subarray signals, respectively, by delays that are individually controlled and providing delayed subarray signals, and a summing circuit for summing said delayed subarray signals and providing a beamformer signal;
• and
• an image generating circuit responsive to said beamformer signal for generating an image of the region of interest.

A method for ultrasound imaging comprising the steps of:

• providing a two-dimensional array of ultrasound transducer elements that define a plurality of subarrays;
• transmitting ultrasound energy into a region of interest along a desired scan line in a three-dimensional space with transmit elements of the array;
• receiving ultrasound energy from said region of interest with receive elements of each of said subarrays and generating transducer signals, wherein the receive elements of each of said subarrays are distributed in at least two dimensions on said two-dimensional array;
• for each of said subarrays, processing said transducer signals in accordance with a desired operation and providing a phased shifted subarray signal;
• delaying each of said phased shifted subarray signals by delays that are individually controlled and providing delayed subarray signals;
• summing said delayed subarray signals and providing a beamformer signal;
• and
• generating an image of the region of interest in response to said beamformer signal.

A method for ultrasound imaging comprising the steps of:

• providing a two-dimensional array of ultrasound transducer elements that define a plurality of subarrays;
• transmitting ultrasound energy into a region of interest along a desired scan line in a three-dimensional space with transmit elements of the array;
• receiving ultrasound energy from said region of interest with receive elements of each of said subarrays and generating transducer signals, wherein the receive elements of each of said subarrays are distributed in at least two dimensions on said two-dimensional array;
• for each of said subarrays, processing the respective transducer signals in accordance with a desired operation and providing first and second subarray signals;
• delaying said first and second subarray signals by delays that are individually controlled and providing delayed subarray signals;
• summing said delayed subarray signals and providing a beamformer signal;
• and
• generating an image of the region of interest in response to said beamformer signal.