Ultrasonic signal processor for a hand held ultrasonic diagnostic instrument

• US 7,740,586 B2
• Filed: 06/12/2007
• Issued: 06/22/2010
• Est. Priority Date: 06/28/1996
• Status: Expired due to Fees

• Current Assignee: FUJIFILM SonoSite, Inc. (Fujifilm Holdings Corporation)
• Original Assignee: Sonosite Incorporated (Fujifilm Holdings Corporation)
• Inventors: Pflugrath, Lauren S., Jones, Geoffrey H., Hwang, Juin-Jet, Doherty, Terrance R.
• Primary Examiner(s): Le; Long V
• Assistant Examiner(s): Selkin; Saurel J
• Application Number:
  US11/762,019
• Publication Number:
  US 20070232910A1
• Time in Patent Office: 1,106 Days
• Field of Search: 600/447, 600/443, 367/135, 310/313.R
• US Class Current: 600/443
• CPC Class Codes: A61B 2560/0456 Apparatus provided with a docking unit
• CPC Class Codes: A61B 8/00 Diagnosis using ultrasonic, sonic or infrasonic waves imaging of objects using sonar G01S15/00
• CPC Class Codes: A61B 8/06 Measuring blood flow measuring volume flow in general G01F, e.g. G01F1/66, G01F1/72; measuring speed of fluids in general G01P5/00
• CPC Class Codes: A61B 8/13 Tomography A61B8/10, A61B8/12 take precedence; tomography for radiation diagnosis A61B6/02
• CPC Class Codes: A61B 8/14 Echo-tomography
• CPC Class Codes: A61B 8/145 characterised by scanning multiple planes
• CPC Class Codes: A61B 8/4427 Device being portable or laptop-like
• CPC Class Codes: A61B 8/4455 Features of the external shape of the probe, e.g. ergonomic aspects
• CPC Class Codes: A61B 8/4472 Wireless probes
• CPC Class Codes: A61B 8/4494 characterised by the arrangement of the transducer elements devices for short-range imaging using particular transducer elements arrangements under G01S15/8909; arrangements of transducers in generation of mechanical vibrations of infrasonic, sonic or ultrasonic frequency B06B1/0607
• CPC Class Codes: A61B 8/46 Ultrasonic, sonic or infrasonic diagnostic devices with special arrangements for interfacing with the operator or the patient
• CPC Class Codes: A61B 8/461 Displaying means of special interest
• CPC Class Codes: A61B 8/462 characterised by constructional features of the display
• CPC Class Codes: A61B 8/467 characterised by special input means
• CPC Class Codes: A61B 8/488 involving Doppler signals
• CPC Class Codes: A61B 8/5269 involving detection or reduction of artifacts for image enhancement algorithms G06T5/00
• CPC Class Codes: A61B 8/54 Control of the diagnostic device
• CPC Class Codes: A61B 8/56 Details of data transmission or power supply
• CPC Class Codes: G01S 15/8915 using a transducer array
• CPC Class Codes: G01S 15/892 the array being curvilinear
• CPC Class Codes: G01S 15/8979 : Combined Doppler and pulse-echo imaging systems
• CPC Class Codes: G01S 15/899 : Combination of imaging systems with ancillary equipment
• CPC Class Codes: G01S 7/52026 : Extracting wanted echo signals Doppler systems G01S15/50; Doppler short range imaging systems G01S15/8979
• CPC Class Codes: G01S 7/52028 : using digital techniques
• CPC Class Codes: G01S 7/52033 : Gain control of receivers for seismic signals G01V1/245
• CPC Class Codes: G01S 7/52034 : Data rate converters
• CPC Class Codes: G01S 7/5206 : Two-dimensional coordinated display of distance and direction; B-scan display
• CPC Class Codes: G01S 7/52068 : Stereoscopic displays; Three-dimensional displays; Pseudo 3D displays G01S15/8993 takes precedence
• CPC Class Codes: G01S 7/52071 : Multicolour displays; using colour coding; Optimising colour or information content in displays, e.g. parametric imaging
• CPC Class Codes: G01S 7/52079 : Constructional features constructional features of transducers B06B; mounting transducers G10K11/00; constructional features of ultrasonic medical diagnostic devices A61B8/44
• CPC Class Codes: G01S 7/5208 : with integration of processing functions inside probe or scanhead
• CPC Class Codes: G01S 7/52085 : Details related to the ultrasound signal acquisition, e.g. scan sequences control of medical diagnostic ultrasound devices A61B8/54
• CPC Class Codes: G01S 7/529 : Gain of receiver varied automatically during pulse-recurrence period for seismic signals G01V1/245
• CPC Class Codes: G10K 11/004 : Mounting transducers, e.g. provided with mechanical moving or orienting device mountings specially adapted to a particular sound-producing device, see the preceding groups G10K1/00 - G10K9/00, e.g. G10K1/26, G10K1/28, G10K9/22; arrangements of sonic watch equipment on submarines B63G8/39; buoys B63B22/00
• CPC Class Codes: G10K 11/345 : using energy switching from one active element to another

Abstract

A hand held ultrasonic instrument is provided in a portable unit which performs both B mode and Doppler imaging. The instrument includes a transducer array mounted in a hand-held enclosure, with an integrated circuit transceiver connected to the elements of the array for the reception of echo signals. A digital signal processing circuit performs both B mode and Doppler signal processing such as filtering, detection and Doppler estimation, as well as advanced functions such as assembly of multiple zone focused scanlines, synthetic aperture formation, depth dependent filtering, speckle reduction, flash suppression, and frame averaging.

Claims

1. A method for reducing signal bandwidth with respect to a signal of an ultrasound device, said method comprising:

receiving ultrasound scan signals in a normalization circuit, wherein said receiving ultrasound scan signals is at an input rate;

coupling ultrasound scan signals to a first finite impulse response filter and producing a first accumulated signal; and

coupling said ultrasound scan signals to a second finite response filter and producing a second accumulated signal,

wherein said first and second finite impulse response filters provide said first and second accumulated signals at a rate less than the input rate.

2. The method of claim 1, wherein each of said first finite impulse response filter and said second finite impulse response filter comprises a multiplier and an accumulator.

3. The method of claim 1, wherein said normalization circuit normalizes said ultrasound scan signals for beam and aperture variation.

4. The method of claim 1, said method further comprising:

multiplying said ultrasound scan signals by a coefficient to produce normalized ultrasound scan signals.

5. The method of claim 1, wherein said ultrasound scan signals are coupled by a multiplexer to said second finite impulse response filter.

6. The method of claim 1, wherein coefficients used by said first and second finite response filters to produce said first and second accumulated signals are supplied by a coefficient memory.

7. The method of claim 1, wherein said first finite impulse response filter produces in phase (I) signal samples.

8. The method of claim 1, wherein said second finite impulse response filter produces quadrature (Q) signal samples.

9. The method of claim 1, wherein a coefficient associated with said first finite impulse response filter and used to produce said first accumulated signal is chosen to multiply said ultrasound scan signals by a weighted cosine function.

10. The method of claim 1, wherein said signal bandwidth is reduced to equal the transducer bandwidth of said ultrasound device.

11. The method of claim 1, wherein said signal bandwidth is reduced to match the display bandwidth of a display monitor of said ultrasound device.

12. The method of claim 1, wherein the effective lengths of each of said first and second finite impulse response filters are adjusted.

13. The method of claim 1, wherein said first and second finite impulse response filters are used to reduce radio frequency noise.

14. The method of claim 1, wherein the output rate is decimated by a variable factor.

15. The method of claim 9, wherein a coefficient associated with said second finite impulse response filter and used to produce said second accumulated signal is chosen to multiply said ultrasound scan signals by a weighted sine function.

16. A digital signal processor for use in an ultrasound device comprising:

a normalization circuit configured for receiving and adjusting ultrasound scan signals for beam variation;

a memory configured for storing partially summed ultrasound scan signals from a portion of a full aperture acquired following at least two separate pulse transmissions; and

an adder configured for combining said partially summed ultrasound scan signals to form full aperture signals.

17. The digital signal processor of claim 16, further comprising:

at least two finite impulse response filters configured for receiving and multiplying ultrasound scan signals, wherein said at least two finite impulse response filters are coupled to said memory by a multiplexer.

18. The digital signal processor of claim 16, further comprising:

a detection and compression circuit, wherein after said lull aperture signals are formed, said full aperture signals are conducted from said adder to said detection and compression circuit.

19. The digital signal processor of claim 18 wherein said detection and compression circuit is configured to compress and scale said full aperture signals to map them to a desired range of display gray levels.

20. A digital signal processor for use in an ultrasound device comprising:

means for normalizing ultrasound scan signals for at least one of beam variation and aperture variation;

means for multiplying said normalized ultrasound scan signals;

means for forming a synthetic aperture, wherein said means for forming a synthetic aperture uses multiplied normalized scanline signals from said means for multiplying acquired following at least two separate pulse transmissions and combined to form full aperture scan signal;

means for compressing and mapping said full aperture scanlines to a desired range of display gray levels.