BEAMFORMER, BEAMFORMING METHOD, ULTRASONIC IMAGING APPARATUS, AND CONTROL METHOD OF ULTRASONIC IMAGING APPARATUS

• US 20150016226A1
• Filed: 07/11/2014
• Published: 01/15/2015
• Est. Priority Date: 07/11/2013
• Status: Abandoned Application

• Current Assignee: IND Academic Cooperation Foundation At Namseoul University, Samsung Electronics Co. Ltd.
• Original Assignee: Industry Academic Cooperation Foundation, Samsung Electronics Co. Ltd.
• Inventors: PARK, Sung Chan, PARK, Su Hyun, KANG, Joo Young, KIM, Jung Ho, BAE, Moo Ho, KIM, Kyu Hong
• Application Number:
  US14/329,325
• Publication Number:
  US 20150016226A1
• Time in Patent Office: Days
• US Class Current: 367/138
• CPC Class Codes: A61B 5/0095 by applying light and detecting acoustic waves, i.e. photoacoustic measurements
• CPC Class Codes: A61B 8/4488 the transducer being a phased array
• CPC Class Codes: G01S 15/8915 using a transducer array
• CPC Class Codes: G01S 7/52047 for elimination of side lobes or of grating lobes; for increasing resolving power
• CPC Class Codes: G10K 11/346 using phase variation

Abstract

Disclosed herein is a beamformer that performs beamforming, including a weight computation processor configured to compute a covariance of a conversion signal which is obtainable by converting an input signal using at least one conversion function, approximate the computed covariance to a Toeplitz matrix form, and compute a conversion signal weight that is a weight for the conversion signal based on the approximation result, and a synthesizer configured to generate an output signal using the conversion signal weight computed by the weight computation processor.

Claims

1. A beamformer comprising:

a weight computation processor configured to compute a covariance of a conversion signal which is obtainable by converting an input signal using at least one conversion function, to approximate the computed covariance to a Toeplitz matrix form, and to compute an input signal weight which includes at least one from among a direct weight for the input signal and a conversion signal weight that is a weight for the conversion signal based on a result of the approximating; and

a synthesizer configured to generate an output signal using the computed input signal weight.

2. The beamformer according to claim 1, wherein the weight computation processor is further configured to compute an approximate matrix by using a result of the approximating, inverting the computed approximate matrix, and computing the conversion signal weight by using a result of the inverting.

3. The beamformer according to claim 1, wherein the weight computation is further configured to compute an approximate matrix by approximating the computed covariance of the conversion signal to the Toeplitz matrix form by using an equation which is expressible as

4. The beamformer according to claim 2, wherein the weight computation processor is further configured to compute the conversion signal weight for the conversion signal by using an equation which is expressible as

5. The beamformer according to claim 4, wherein the steering vector v₁ includes a steering vector that is converted by using at least one conversion function.

6. The beamformer according to claim 4, wherein the conversion signal weight includes a weight that is assigned to the at least one conversion function in order to compute an optimal value of the input signal weight.

7. The beamformer according to claim 4, wherein the weight computation processor includes a converter which is configured to compute the conversion signal by using an equation which is expressible as

u=V^Hx

wherein u is a conversion signal, V is a conversion function, and x is an input signal.

8. The beamformer according to claim 4, wherein the at least one conversion function is configured with a combination of basis vectors which are obtainable by performing a principal component analysis for an optimal value of the input signal weight which is computed by using a minimum variance.

9. The beamformer according to claim 4, wherein the at least one conversion function reduces a number of dimensions of the input signal.

10. The beamformer according to claim 4, wherein the at least one conversion function is configured based on at least one orthogonal basis vector.

11. The beamformer according to claim 10, wherein the at least one orthogonal basis vector includes at least one from among an eigenvector and a Fourier basis vector.

12. A beamforming method comprising:

computing a covariance of a conversion signal which is obtainable by converting an input signal using at least one conversion function;

approximating the computed covariance to a Toeplitz matrix form;

computing an input signal weight which includes at least one from among a direct weight for the input signal and a conversion signal weight for the conversion signal based on a result of the approximating; and

generating an output signal using the computed input signal weight.

13. The beamforming method according to claim 12, wherein the approximating comprises computing an approximate matrix.

14. The beamforming method according to claim 13, wherein the computing the approximate matrix comprises using an equation which is expressible as

15. The beamforming method according to claim 13, wherein the computing the input signal weight includes:

inverting the computed approximate matrix; and

computing the conversion signal weight by using a result of the inverting the computed approximate matrix.

16. The beamforming method according to claim 15, wherein the computing the conversion signal weight comprises using an equation which is expressible as

17. The beamforming method according to claim 12, wherein the at least one conversion function is configured with a combination of basis vectors which are obtainable by performing a principal component analysis for an optimal value of the input signal weight which is computed by using a minimum variance method.

18. A non-transitory computer readable medium having recorded thereon a program executable by a computer for performing a beamforming method, the method comprising:

computing a covariance of a conversion signal which is obtainable by converting an input signal using at least one conversion function;

approximating the computed covariance to a Toeplitz matrix form;

computing an input signal weight which includes at least one from among a direct weight for the input signal and a conversion signal weight for the conversion signal based on a result of the approximating; and

providing the computed input signal weight to a synthesizer which is configured for generating a signal using the computed input signal weight.

19. The non-transitory computer readable medium according to claim 18, wherein the approximating comprises computing an approximate matrix.

20. The non-transitory computer readable medium according to claim 19, wherein the computing the approximate matrix comprises using an equation which is expressible as