Dynamic sub-array mapping systems and methods for ultrasound imaging

• US 20050243812A1
• Filed: 04/28/2004
• Published: 11/03/2005
• Est. Priority Date: 04/28/2004
• Status: Active Grant

• Current Assignee: Siemens Medical Solutions USA Incorporated (Siemens AG)
• Original Assignee: Siemens Medical Solutions USA Incorporated (Siemens AG)
• Inventors: Phelps, Robert N.
• Granted Patent: US 7,635,334 B2
• Time in Patent Office: Days
• US Class Current: 370/360
• CPC Class Codes: G01S 15/8925 the array being a two-dimensional transducer configuration, i.e. matrix or orthogonal linear arrays
• CPC Class Codes: G01S 15/8927 using simultaneously or sequentially two or more subarrays or subapertures
• CPC Class Codes: G01S 7/5208 with integration of processing functions inside probe or scanhead
• CPC Class Codes: G10K 11/346 using phase variation

Abstract

Elements within each of a plurality of sub-arrays are dynamically grouped as a function of the steering direction. The dynamic grouping allows for partial beamforming with more similar delays within each grouping of elements within the sub-array. A plurality of partial beamformers is provided for each sub-array. Different ones of the elements are mapped to different ones of the partial beamformers as a function of the steering direction. As used herein, steering direction includes one or more of a focal location, a scan line angle, a scan line origin or other beamforming parameters associated with establishing a relative delay between elements. The shape or grouping of elements is changed at the beginning of any acquisition cycle, such as the beginning of transmit and receive operation for a given steering direction. Dynamic sub-array mapping may minimize negative effects of sub-array partial beamforming by providing an optimal shape of the sub-array groupings based on the steering direction.

Claims

1. A method for dynamic sub-array mapping in ultrasound beamformation, the method comprising:

(a) grouping elements of a first sub-array of an array into at least first and second groups as a function of a first steering direction;

(b) receiving signals from the elements of the first group;

(c) applying one of different relative delays, different relative phase shifts or combinations thereof to the signals within the first group;

(d) combining the signals within the first group after (c).

2. The method of claim 1 wherein (a) is performed differently for each of a plurality of different steering directions, at least one element being in the first group for the first steering direction and in the second group for a second steering direction.

3. The method of claim 1 further comprising:

(e) performing (a), (b), (c) and (d) separately for each of a plurality of sub-arrays of the array at a substantially same time, the first sub-array of (a) being one of the plurality of sub-arrays.

4. The method of claim 1 further comprising:

(e) receiving signals from the elements of the second group;

(f) applying at least one of different relative delays or different relative phase shifts to the signals within the second group;

(g) combining the signals within the second group after (f).

5. The method of claim 1 further comprising:

(e) performing (d) within a transducer assembly;

(f) combining the signals within the second group; and

(g) beamforming from the combined signals of the first group with the combined signals of the second group within an imaging system.

6. The method of claim 1 wherein (c) and (d) comprise partial beamforming.

7. The method of claim 1 wherein (d) comprises summing the signals within the first group.

8. The method of claim 1 wherein (b) comprises receiving pulsed signals.

9. The method of claim 1 wherein the sub-array comprises a multi-dimensional array and (a) comprises grouping the elements of the first and second groups as multi-dimensional groupings.

10. The method of claim 1 further comprising:

(e) including within the first group additional elements from a second sub-array different than and adjacent to the first sub-array.

11. The method of claim 10 further comprising:

(f) selecting the additional elements as a function of the first steering direction.

12. A method for dynamic sub-array mapping in ultrasound beamformation, the method comprising:

(a) grouping elements of a first sub-array of an array into at least first and second groups as a function of a first steering direction;

(b) receiving first pulsed wave signals from the elements of the first group and second pulse wave signals from the elements of the second group;

(c) combining the first pulsed wave signals from the first group of elements; and

(d) combining the second pulsed wave signals from the second group of elements separately from (c).

13. The method of claim 12 wherein (c) and (d) comprise partially beamforming the first and second pulsed wave signals, respectively;

further comprising;

(e) performing (c) and (d) within a transducer assembly; and

(f) beamforming first and second outputs of (c) and (d) within an imaging system.

14. The method of claim 12 further comprising:

(e) grouping elements of a second sub-array of the array into at least second and third groups as a function of the first steering direction;

(f) including at least one element of the second sub-array in the first group of elements.

15. A system for dynamic sub-array mapping in ultrasound beamformation, the system comprising:

an array of elements;

first and second partial beamformers; and

a first plurality of switches operable to group elements of a first sub-array of the array into at least first and second groups as a function of a first steering direction, the first group connected with the first partial beamformer and the second group connected with the second partial beamformer;

wherein the first and second partial beamformers are operable to apply one of different relative delays, different relative phase shifts or combinations thereof to signals from elements within the first and second groups, respectively, and combining the signals from elements within the first and second groups, respectively.

16. The system of claim 15 wherein N partial beamformers including the first and second partial beamformers are connectable with the first sub-array and wherein the plurality of switches comprise a 1-to-N router operable to connect any one of the elements of the first sub-array with any one of the N partial beamformers.

17. The system of claim 16 further comprising:

M additional partial beamformers connectable with a second sub-array; and

a second plurality of switches operable to connect any one of the elements of the second sub-array with any one of the M additional partial beamformers.

18. The system of claim 17 wherein the M additional partial beamformers are free of connection with elements of the first sub-array and the N partial beamformers are free of connection with elements of the second sub-array.

19. The system of claim 17 wherein the first sub-array is adjacent to the second sub-array on the array;

further comprising;

a third plurality of switches operable to connect elements of the first sub-array with at least one of third or fourth partial beamformer.

20. The system of claim 15 further comprising:

third and fourth partial beamformers connectable with a second sub-array of the array; and

a second plurality of switches operable to group elements of the second sub-array into third and fourth groups as a function of the steering direction, the third group connected with the third partial beamformer and the fourth group connected with the fourth partial beamformer.

21. The system of claim 15 wherein the first partial beamformer comprises:

at least one of a phase rotator or a delay for each of the elements of the first group; and

a summer connected with each of the phase rotators or delays.

22. The system of claim 15 further comprising:

a transducer assembly at least in part including the array and the first and second partial beamformers; and

an ultrasound imaging system having a receive beamformer having first and second channels connectable with the first and second partial beamformers.

23. The system of claim 15 further comprising:

a controller operable to reconfigure the first plurality of switches as a function of different steering directions, at least one element being in the first group for the first steering direction and in the second group for a second steering direction.

24. The system of claim 15 wherein the sub-array comprises a multi-dimensional array and the first and second groups comprise multi-dimensional groupings of elements.