Communications – electrical: acoustic wave systems and devices – Transmitter systems – With beam forming – shaping – steering – or scanning
Reexamination Certificate
2000-08-28
2002-03-26
Pihulic, Daniel T. (Department: 3662)
Communications, electrical: acoustic wave systems and devices
Transmitter systems
With beam forming, shaping, steering, or scanning
Reexamination Certificate
active
06363033
ABSTRACT:
REFERENCE TO MICROFICHE APPENDIX
This application includes a microfiche appendix of 195 sheets of microfiche having 19,058 frames. A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by any one of the patent disclosure, as it appears in the Patent and Trademark Office patent files or records, but otherwise reserves all copyright rights whatsoever.
1. Field of the Invention
This invention relates to coherent imaging systems including, for example, radar, sonar, seismic, and ultrasound systems, using vibratory energy, and in particular, but not limited to, phased array ultrasound imaging systems for scan formats such as linear, steered linear, sector, circular, Vector®, steered Vector® and other types of scan formats in imaging modes such as, by way of example only, B-mode (gray-scale imaging mode), F-mode (flow or color Doppler imaging mode), M-mode (motion mode) and D-mode (spectral Doppler mode). Although the invention will be discussed with respect to an ultrasound system, the invention can be implemented with other types of coherent imaging systems.
2. Background of the Invention
A. Literature
The open literature, which presents issues relevant to imaging systems in general, includes the following documents which are incorporated herein by reference:
1. Dan E. Dudgeon, “Fundamentals of Digital Array Processing,”
Proceedings of the IEEE,
volume 65, pp. 899-904, June 1977.
2. Dan E. Dudgeon and Russell M. Mersereau,
Multidimensional Digital Signal Processing,
Chapter 6, Section 2: “Beamforming,” Prentice Hall, 1984.
3. William C. Knight, Roger G. Pridham, and Steven M. Kay, “Digital Signal Processing for Sonar,”
Proceedings of the IEEE,
volume 69, pages 1451-1506, November 1981. (Digital beamformers for use in sonar described on pages 1465-1471.)
4. Roger G. Pridham and Ronald A. Mucci, “A Novel Approach to Digital Beamforming,”
Journal of the Acoustical Society of America,
volume 63, pages 425-434, February 1978.
5. Roger G. Pridham and Ronald A. Mucci, “Digital Interpolation Beamforming for Low-Pass and Bandpass Signals,”
Proceedings of the IEEE,
volume 67, pages 904-919, June 1979.
6. P. Barton, “Digital Beamforming for Radar,”
IEE Proceedings,
volume 127, part F, number 4, August 1980.
7. P. D. Carl, G. S. Kino, C. S. Desilets and P. M. Grant, “A Digital Synthetic Focus Acoustic Imaging System,”
Acoustic Imaging,
volume 8, pp. 39-53, 1978.
8. B. D. Steinberg, “Digital Beamforming in Ultrasound,”
IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control,
volume 39, pp. 716-721, November 1992.
9. Hans Steyskal, “Digital Beamforming Antennas,”
Microwave Journal,
volume 30, No. 1, pp. 107-124, January 1987.
10. R. E. Crochiere and L. R. Rabiner, “Multirate Digital Signal Processing,” Chapter 2, Prentice Hall, 1983.
B. Analog and Hybrid (Analog-Digital) Beamformer Systems
Relevant analog and hybrid (analog-digital) phased array beamformer system art can be found in the following patents which are incorporated herein by reference:
U.S. Pat. No.:
Title:
Iventor(s):
4,140,022
MULTIPLE
Samuel H. Maslak
TRANSDUCER
ACOUSTIC IMAGING
APPARATUS
4,550,607
PHASED ARRAY
Samuel H. Maslak
ACOUSTIC IMAGING
J. Nelson Wright
SYSTEM
4,699,009
DYNAMICALLY
Samuel H. Maslak
FOCUSED LINEAR
Hugh C. Larsen
PHASED ARRAY
ACOUSTIC IMAGING
SYSTEM
5,014,710
STEERED LINEAR
Samuel H. Maslak
and
COLOR DOPPLER
Donald J. Burch
5,165,413
IMAGING
J. Nelson Wright
Hugh C. Larson
Donald R. Langdon
Joel S. Chaffin
Grant Flash, III
C. Digital Receive Beamformer Systems
The concept of a digital receive beamformer system has been proposed in the art with respect to ultrasound systems. By way of example, the following U.S. patents, all of which are incorporated herein by reference, discuss various aspects of such systems. The patents include:
U.S. Pat. No.:
Title:
Inventor(s):
4,809,184
METHOD AND APPARATUS
Matthew O'Donnell
FOR FULLY DIGITAL
Mark Magrane
BEAM FORMATION IN A
PHASED ARRAY COHERENT
IMAGING SYSTEM
4,839,652
METHOD AND APPARATUS
Matthew O'Donnell
FOR HIGH SPEED
William E. Engeler
DIGITAL PHASED ARRAY
Thomas L. Vogelsong
COHERENT IMAGING
Steven C. Karr
SYSTEM
Sharbel E. Noujaim
4,886,069
METHOD OF, AND
Matthew O'Donnell
APPARATUS FOR,
OBTAINING A
PLURALITY OF
DIFFERENT RETURN
ENERGY IMAGING BEAMS
RESPONSIVE TO A SINGLE
EXCITATION EVENT
4,893,284
CALIBRATION OF
Mark C. Magrane
PHASED ARRAY
ULTRASOUND PROBE
4,896,287
CORDIC COMPLEX
Matthew O'Donnell
MULTIPLIER
William E. Engeler
4,975,885
DIGITAL INPUT STAGE
Dietrich Hassler
FOR AN ULTRASOUND
Erhard Schmidt
APPARATUS
Peter Wegener
4,983,970
METHOD AND
Matthew O'Donnell
APPARATUS FOR
William E. Engeler
DIGITAL PHASED
John J. Bloomer
ARRAY IMAGING
John T. Pedicone
5,005,419
METHOD AND
Matthew O'Donnell
APPARATUS FOR
Kenneth B. Welles, II
COHERENT IMAGING
Carl R. Crawford
SYSTEM
Norbert J. Plec
Steven C. Karr
5,111,695
DYNAMIC PHASE
William E. Engeler
FOCUS FOR COHERENT
Matthew O'Donnell
IMAGING BEAM
John T. Pedicone
FORMATION
Jobn J. Bloomer
5,142,649
ULTRASONIC IMAGING
Matthew O'Donnell
SYSTEM WITH MULTIPLE,
DYNAMICALLY FOCUSED
TRANSMIT BEAMS
5,230,340
ULTRASOUND IMAGING
Thendor L. Rhyne
SYSTEM WITH IMPROVED
DYNAMIC FOCUSING
5,235,982
DYNAMIC TRANSMIT
Matthew O'Donnell
FOCUSING OF
A STEERED
ULTRASONIC BEAM
5,249,578
ULTRASOUND IMAGING
Sidney M. Karp
SYSTEM USING FINITE
Raymond A. Beaudin
IMPULSE RESPONSE
DIGITAL CLUTTER FILTER
WITH FORWARD AND
REVERSE COEFFICIENTS
The basic feature of a digital receive beamfomer system as disclosed above can include: (1) amplification of the ultrasound signal received at each element of an array such as, for example, a linear array; (2) direct per channel analog-to-digital conversion of the ultrasound signal with an analog-to-digital sampling rate at least twice the highest frequency in the signal; (3) a digital memory to provide delays for focusing; and (4) digital summation of the focused signals from all the channels. Other processing features of a receive beamformer system can include phase rotation of a receive signal on a channel-by-channel basis to provide fine focusing, amplitude scaling (apodization) to control the beam sidelobes, and digital filtering to control the bandwidth of the signal.
D. Transmit Beamforming
The above literature points out the ever-present desire to achieve more accurate focusing, better resolution, better sensitivities and higher frame rates in ultrasonic images. In order to do so, versatile adjustments of the beamforming characteristics are required in order to optimize the results for a given scan requirement. The greatest versatility is obtained when the ultrasound instrument can entirely change the number of beams transmitted simultaneously, the pulse waveform (PW) or continuous waveform (CW) characteristics, time delays and apodization values on a per-scan-line basis. However, such versatility can undesirably require extensive hardware resources if carried out in a direct implementation.
The above literature reveals extensive effort in the improvement of images through the use primarily of improved receive beamformers. Receive beamformers which employ digital techniques and digital signal processing have been reported in the prior art, though substantial improvements are still possible through innovative designs. Little effort, however, has been made to improve the characteristics of transmit beam formation. In the past, transmit beams were typically gated carrier pulses generated at a desired carrier frequency by analog circuitry. The only flexibility which was available to optimize the transmit pulse waveform shape (envelope) was typically an ability to specify the length of the pulse in terms of an integer number of carrier cycles it should contain, and some fixed analog filtering. Apodization and delay profiles for beamforming would be specified, and typically implemented in an analog fashion as well, with inherent precision limitations. The envelope shape of a pulse waveform was oth
Cole Christopher R.
Gee Albert
Liu Thomas
Acuson Corporation
Brinks Hofer Gilson & Lione
Pihulic Daniel T.
LandOfFree
Method and apparatus for transmit beamformer system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for transmit beamformer system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for transmit beamformer system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2820743