Ex Parte Rigby et al

Board of Patent Appeals and Interferences

Jun 26, 2012

11294047 (B.P.A.I. Jun. 26, 2012)

UNITED STATES PATENT AND TRADEMARKOFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
11/294,047 12/05/2005 Kenneth Wayne Rigby 158962-1 5691
7590 06/27/2012
General Electric Company
GEGR Patent Docket Rm.
Bldg. K-1 Rm. 4A59
One Research Circle
Niskayuna, NY 12309
EXAMINER
MEHTA, PARIKHA SOLANKI
ART UNIT PAPER NUMBER
3737
MAIL DATE DELIVERY MODE
06/27/2012 PAPER
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE
__________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
__________

Ex parte
KENNETH WAYNE RIGBY and CHRISTOPHER ROBERT HAZARD
__________

Appeal 2010-009948
Application 11/294,047
Technology Center 3700
__________

Before TONI R. SCHEINER, DONALD E. ADAMS, and STEPHEN WALSH,
Administrative Patent Judges.

SCHEINER, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 from the final rejection of
claims 1-30, directed to a method for correcting beamforming time delays in
an ultrasound system, and to an ultrasound system. The Examiner has
rejected the claims on the grounds of anticipation, obviousness, and double
patenting. We have jurisdiction under 35 U.S.C. § 6(b).
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STATEMENT OF THE CASE
Ultrasound systems comprise an array of transducer
elements used for transmitting a set of waveforms into an
imaging subject and for receiving a set of reflected ultrasound
signals. Each waveform is emitted with a relative time delay
chosen to focus the net transmitted waveform in a desired
direction and depth and with a desired shape. Similarly each
received signal is individually delayed to maximize the
response of the system to reflected energy for a desired
direction and depth and with a desired shape. The delayed
receive signals are summed and processed to create and display
an image of the imaging subject.
(Spec. ¶ 3.)
“The transmit and receive time delays, known collectively as
beamforming time delays, are typically calculated assuming that sound
propagates through the body with a known, constant speed” (id. at ¶ 4). “If
the assumption [of a known, fixed sound speed] is not correct, the delayed
receive signals will not be well-aligned in time; [and] the arrival time errors
will be large” (id. at ¶ 5). As a result, “transmit and receive focusing is
degraded and there will be a loss of image resolution and contrast” (id. at ¶
4).
“By correcting the beamforming delays for the arrival time errors, the
focusing will be improved and image resolution and contrast will increase”
(id. at ¶ 5). According to the Specification, “arrival time delay errors may
be estimated using one of several methods that are well known in the art”
(id.).
The Specification discloses a method by which beamforming time
delay errors are estimated and corrected at paragraphs 40-84, with particular
reference to Figures 2, 3, 7, and 8.
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Claims 1-30 are pending and on appeal. Claims 1 and 20 are
representative of the subject matter on appeal:
1. A method for correcting beamforming time delays in an
ultrasound system, comprising:
transmitting a beam of ultrasound energy through an object using an
array of transducer elements, wherein each transducer element is configured
to transmit the beam of ultrasound energy with a transmit beamforming time
delay;
receiving a plurality of echo signals, wherein each transducer element
is configured to receive the beam of ultrasound energy with a receive
beamforming time delay;
estimating beamforming time delay errors for each echo signal and
beam direction;
correcting the transmit and receive beamforming time delays
employing the estimated beamforming time delay errors; and
generating an ultrasound image of the object using the corrected
transmit and receive beamforming time delays.
20. An ultrasound system for estimating beamforming time delay,
the ultrasound system comprising:
a transducer array having a set of array elements disposed in a pattern,
each of the elements being separately operable to transmit a beam of
ultrasound energy into an object during a transmission mode and to produce
an echo signal in response to vibratory energy impinging on the transducer
array during a receive mode;
a transmitter coupled to the transducer array and being operable
during the transmission mode to apply a separate transmit signal pulse with a
respective transmit beamforming time delay to each of the array elements
such that a directed transmit beam is produced;
a receiver coupled to the transducer array and being operable during
the receive mode to sample the echo signal produced by each of the
transducer array elements and to impose a receive beamforming time delay
on each said echo signal sample to generate a corresponding plurality of
receive signals;
a beamformer system configured to estimate the arrival time errors for
each echo signal and each beam direction and correct the transmit and
receive beamforming time delays; and
an image [processor] configured to generate an ultrasound image.
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The claims stand rejected as follows:
I. Claims 1-4, 6, 20, and 21 under 35 U.S.C. § 102(b) as anticipated
by Rigby1 (Ans. 3).
II. Claim 5 under 35 U.S.C. § 103(a) as unpatentable over Rigby
(Ans. 3-4).
III. Claims 7-18 and 22-30 under 35 U.S.C. § 103(a) as unpatentable
over Rigby and Wright2 (Ans. 4-5).
IV. Claim 19 under 35 U.S.C. § 103(a) as unpatentable over Rigby,
Wright, and Xu3 (Ans. 5).
V. Claims 1, 2, and 20 on the ground of nonstatutory obviousness-
type double patenting as unpatentable over claims 1-22 and 30-34 of
US Application 10/882,910.4
We affirm-in-part.
ANTICIPATION
I.
Claims 1-4, 6, 20, and 21 stand rejected as anticipated by Rigby. The
Examiner’s fact findings regarding Rigby’s disclosure are set forth on page 3
of the Answer. In particular, the Examiner finds that Rigby “discloses
means and steps for calculating a normalized sum and mapping the sum into
imaging and transducer element directions (col. 9, lines 29-39)” (Ans. 3),

1 US 5,388,461, issued February 14, 1995 to Rigby et al.
2 US 5,570,691, issued November 5, 1996 to Wright et al.
3 Xiao-Liang Xu et al., Time Delay Estimation Using Wavelet Transform for
Pulsed-Wave Ultrasound, 23 ANNALS OF BIOMEDICAL ENGINEERING 612-
621(1995).
4 Now US 7,740,583, issued June 22, 2010 to Kenneth Wayne Rigby &
Steven Charles Miller.
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and further “discloses the normalized correlation sum as being obtained
using a sum of magnitudes of the beamsum and channel signals (col. 7, lines
43-54)” (id.). These portions of Rigby are as follows:
FIG. 3 shows the present invention implemented in large
part by a time delay correction processor 122 contained in mid-
processor 102. Time delay correction processor 122 receives
the I and Q components of the beamsum samples and the I and
Q components of the samples from each receiver channel and,
from these components, calculates time delay correction values
Tc,k, as described in detail below. These values are supplied to
digital controller 16, shown in FIG. 1, which recalculates the
transmit time delays Tt,k and the receive times delays Tr,k for use
in subsequent transmit/receive beam cycles.
(Rigby, col. 7, ll. 43-54.)
Alternatively, filtering operations can be performed in the
digital controller before applying the time delay corrections to
the transmit and receive time delays in order to improve the
quality and robustness of the time delay correction estimates.
The filtering on the time delay correction estimates can be
across the estimates for each transmit/receive channel on a
given beam direction, or across each beam direction for a given
channel, or most generally, across both channels and beam
directions.
(Rigby, col. 9, ll. 29-38.)
Appellants contend that “Rigby fails to teach each and every element
of claims 1 and 20” (App. Br. 16). Specifically, Appellants contend that
Rigby does not disclose “normalizing the correlation sums, and there is no
reference to “sums of magnitudes of beamsum and channel signals” (id. at
13). In addition, Appellants contend that the reference “does not teach the
recitations of correcting the transmit and receive beamforming time delays
employing the estimated beamforming time delay errors, wherein the step of
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correcting includes, inter alia, calculating a normalized sum associated
with beamforming channels and beams of claims 1 and 20” (id. at 13).
Appellants acknowledge that Rigby discloses “generation of the
beamsum signal by summing of the separately delayed array element echo
signal samples and cross-correlation of the reference beamsum signal with
each separately delayed array element” (id. at 14), but contend that Rigby
“fails to specifically disclose generation of a complex correlation sum
representative of the time delay between each receive echo signal and the
sum of one or more receive echo signals” and “also fails to disclose
calculating normalized correlation sums for each beam direction and each
element direction” (id.).
That is, Appellants contend that Rigby “is silent regarding the
computation of normalized correlation sums for each beam direction and
each element direction as taught by the present application” (id. at 15), and
that column 7, lines 43-54, cited by the Examiner, actually supports
Appellants’ assertion that Rigby does not calculate normalized correlation
sums for each beam direction and each element direction (id. at 14). Indeed,
Appellants contend that “equations (4) and (5) of Rigby clearly demonstrate
that the correlation sum is not normalized” (id.).
Appellants further contend that “Rigby fails to teach mapping the
normalized correlation sums into beam and element directions, modifying
the mapped correlation sums and filtering the modified correlation sums
over beam and element directions to generate filtered correlation sums” (id.),
and also “fails to disclose labeling each mapped correlation sum as a reliable
correlation sum or an unreliable correlation sum” (id.). Finally, Appellants
contend that “Rigby fails to teach use of either the squared magnitude of the
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beamsum signals and the squared magnitude of the channel signal or the
summed magnitudes if the beamsum signal and the summed magnitudes of
the channel signals as input signals to the correlation sum processor” (id.).
Appellants’ arguments are not persuasive. It may well be, as
Appellants assert, that “Rigby fails to disclose systems and methods for
estimation and compensation of time delays in an ultrasound system as
taught by the present application” (App. Br. 13 (emphasis added)).
However, as noted and reiterated by the Examiner (Ans. 6-7), these specific
limitations are not recited in claims 1 and 20. It is well settled that
limitations from the Specification must not be imported into the claims - in
other words, “it is improper to ‘confin[e] the claims to th[e] embodiments’
found in the specification . . . .”’ In re Trans Texas Holdings Corp., 498 F.3d
1290, 1299 (Fed. Cir. 2007) (citations omitted, bracketed text in internal
quotes in original).
The rejection of claims 1 and 20 as anticipated by Rigby is affirmed.
Claims 2-4, 6, and 21 fall with claims 1 and 20, as they were not separately
argued. 37 C.F.R. ¶ 41.37(c)(1)(vii).5

5 See also, In re McDaniel, 293 F.3d 1379, 1383 (Fed. Cir. 2002):

[T]o assure separate review by the Board of individual claims
within each group of claims subject to a common ground of
rejection, an appellant’s brief to the Board must contain a clear
statement for each rejection: (a) asserting that the patentability
of claims within the group of claims subject to this rejection do
not stand or fall together, and (b) identifying which individual
claim or claims within the group are separately patentable and
the reasons why the examiner’s rejection should not be
sustained.

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OBVIOUSNESS
II.
Claim 5 stands rejected as unpatentable over Rigby. Claim 5, by
virtue of its dependence on claims 2 and 3, requires correcting beamforming
time delays by generating a complex correlation sum representative of the
time delay between each receive echo signal and the sum of one or more
receive echo signals, which further involves calculating normalized
correlation sums associated with beamforming channels and beams, wherein
“each normalized correlation sum is obtained using a sum of the squared
magnitude of a beamsum signal and a sum of the squared magnitude of a
channel signal” (claim 5).
As discussed above, the Examiner finds that Rigby “discloses means
and steps for calculating a normalized sum and mapping the sum into
imaging and transducer element directions” (Ans. 3), and also “discloses the
normalized correlation sum as being obtained using a sum of magnitudes of
the beamsum and channel signals” (id.). The Examiner concedes that Rigby
“does not teach . . . employing the sum of the squared magnitudes” (id.).
However, the Examiner takes the position that it would have been “an
obvious matter of design choice . . . to have squared the beamsum and
channel magnitudes prior to applying them” (id. at 4) because “one of
ordinary skill in the art would expect Applicant’s invention to work equally
well with either the absolute or squared magnitudes” (id.).
Nevertheless, as discussed above, Appellants contend that Rigby does
not calculate normalized correlation sums associated with beamforming
channels and beams in the first place (App. Br. 13-15). In any case,
Appellants contend that normalizing each correlation sum in the manner
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required by claim 5 “is not an arbitrary operation” (App. Br. 17).
Essentially, Appellants contend that the Specification teaches that “using a
sum of the squared magnitude of a beamsum signal and the sum of the
squared magnitude of a channel signal” (as required by claim 5) provides an
exact mathematical normalization of the correlation sum, which provides
greater accuracy, whereas using the sums of magnitudes provides an
approximation to the normalized correlation sum, which is less accurate, but
may be more suited to calculation by digital hardware (App. Br. 17-18;
Spec. ¶ 52).
We agree with Appellants that the Examiner has not established that
Rigby discloses calculating normalized correlation sums associated with
beamforming channels and beams, or that it would have been obvious to
calculate a normalized correlation sum using a sum of the squared
magnitude of the beamsum signal and a sum of the squared magnitude of a
channel signal.
The rejection of claim 5 as unpatentable over Rigby is reversed.
III. & IV.
Claims 7-18 and 22-30 stand rejected as unpatentable over Rigby and
Wright, while claim 19 stands rejected as unpatentable over Rigby, Wright,
and Xu.
Claims 7-19, by virtue of their direct or indirect dependence on claims
2 and 3, require correcting beamforming time delays by generating a
complex correlation sum representative of the time delay between each
receive echo signal and the sum of one or more receive echo signals, which
further involves calculating normalized correlation sums associated with
beamforming channels and beams, mapping the normalized correlation sums
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into beam directions and element directions, and modifying the mapped
correlation sums by “labeling each mapped correlation sum as a reliable
correlation sum or an unreliable correlation sum” (claim 7), and filtering the
modified correlation sums over beam directions and element directions to
generate filtered correlation sums.
Similarly, claims 22-30, by virtue of their direct or indirect
dependence on claim 21, require the ultrasound system to calculate a
normalized correlation sum for each beamforming channel and transducer
element, and map the normalized correlation sums to beam direction and
transducer element order, “wherein the beamformer system is configured to
label each mapped correlation sum as a reliable correlation sum or an
unreliable correlation sum” (claim 22).
Appellants contend that “normalization of the correlation sums is a
critical step before filtering the modified correlation sums” in the present
invention (App. Br. 19). Appellants contend that Rigby does not calculate
normalized correlation sums associated with beamforming channels and
beams (see e.g., id. at 13-15). Moreover, Appellants contend that “Wright
merely restates what is well known to those with ordinary skill in the art”
(id.). “Specifically, Wright states that the magnitude of the cross correlation
is a measure of the degree of similarity of the two component signals . . .
[and] those skilled in the art would realize that as the similarity of the two
component signals increases, the reliability of the estimated time delay
between them increases” (id.). Appellants contend that Wright’s only
suggestion of how to use the indication of reliability to improve the
effectiveness of the beamforming time delay corrections is merely to omit
using unreliable cross-correlations” (id.).
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We agree with Appellants that the Examiner has not established that
Rigby discloses calculating normalized correlation sums associated with
beamforming channels and beams, and by extension, has not established that
it would have been obvious to label mapped normalized correlation sums as
reliable or unreliable.
The rejection of claims 7-18 and 22-30 as unpatentable over Rigby
and Wright is reversed, as is the rejection of claim 19 as unpatentable over
Rigby, Wright, and Xu.
DOUBLE PATENTING
V.
Claims1, 2, and 20 stand rejected on the ground of nonstatutory
obviousness-type double patenting as unpatentable over claims 1-22 and 30-
34 of Application No. 10/882,910 (now US 7,740,583).
Appellants indicate they “will determine whether the filing of a
terminal disclaimer is appropriate” when “the Examiner has indicated
allowable subject matter” (App. Br. 27).
As Appellants do not dispute the merits of the rejection, it is
summarily affirmed.
SUMMARY
I. The rejection of claims 1-4, 6, 20, and 21 as anticipated by Rigby is
affirmed.
II. The rejection of claim 5 as unpatentable over Rigby is reversed.
III. The rejection of claims 7-18 and 22-30 as unpatentable over
Rigby and Wright is reversed.
IV. The rejection of claim 19 as unpatentable over Rigby, Wright,
and Xu is reversed.
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V. The rejection of claims 1, 2, and 20 on the ground of nonstatutory
obviousness-type double patenting is affirmed.

TIME PERIOD FOR RESPONSE
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).

AFFIRMED-IN-PART

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