Ex Parte Chen et al

Patent Trial and Appeal Board

Mar 10, 2015

12170319 (P.T.A.B. Mar. 10, 2015)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

Ex parte RUNHUA CHEN, EKO N. ONGGOSANUSI,
BADRI VARADARAJAN, and ANAND G. DABAK
____________

Appeal 2012-011494
Application 12/170,319
Technology Center 2600
____________

Before CAROLYN D. THOMAS, JOHN A. EVANS,
and JOSEPH P. LENTIVECH, Administrative Patent Judges.

LENTIVECH, Administrative Patent Judge.

DECISION ON APPEAL
Appellants
1
seek our review under 35 U.S.C. § 134(a) of the
Examiner’s Final Rejection of claims 1–60, the only claims pending in the
application on appeal. Br. 2. We have jurisdiction over the pending claims
under 35 U.S.C. § 6(b).
We affirm-in-part.

1
According to Appellants, the real party in interest is Texas Instruments
Incorporated. Br. 1.
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STATEMENT OF THE CASE
Appellants’ Invention
Appellants’ invention generally relates to transmission rank and
precoding matrix index (PMI) feedback schemes. Spec. ¶ 21. Claim 1,
which is illustrative, reads as follows:

1. A receiver, comprising:
a receive unit configured to receive transmissions from
multiple antennas;
a rank feedback unit configured to provide a transmission
rank selection, wherein the transmission rank selection
corresponds to a transmission rank feedback reduction scheme;
and
a precoding feedback unit configured to provide a
precoding matrix selection, wherein the precoding matrix
selection corresponds to a precoding matrix feedback reduction
scheme.

Reference
The Examiner relies on the following prior art in rejecting the claims:
Khojastepour et al. US 2007/0191066 A1 August 16, 2007
(hereinafter “Khojastepour”)

Rejection
Claims 1–60 stand rejected under 35 U.S.C. § 102(e) as anticipated by
Khojastepour. Br. 11.

Rather than repeat the arguments here, we refer to the Brief (“Br.”
filed November 14, 2011) for the positions of Appellants and the Answer
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(“Ans.” mailed May 3, 2012) for the positions of the Examiner. Only those
arguments actually made by Appellants have been considered in this
decision. Arguments that Appellants did not make in the Briefs have not
been considered and are deemed to be waived. See 37 C.F.R.
§ 41.37(c)(1)(vii) (2011).

ANALYSIS
CLAIM 1
Appellants contend that Khojastepour does not teach that “the
transmission rank selection corresponds to a transmission rank feedback
reduction scheme” (hereinafter the “rank feedback limitation”) nor that “the
precoding matrix selection corresponds to a precoding matrix feedback
reduction scheme” (hereinafter the “precoding matrix feedback limitation”)
(hereinafter collectively referred to as the “feedback limitations”), as recited
in claim 1, because Khojastepour does not teach reducing the amount of
feedback information transmitted from the user equipment. Br. 13.
According to Appellants, Khojastepour teaches the feedback of complete
matrix columns, which considerably increases the amount of data fed back
to the base station, and, therefore, teaches away from any type of feedback
reduction scheme. Br. 13 (citing Khojastepour ¶¶ 46–56). Appellants
further argue:
Examiner and Khoj[astepour] admit that the reference
beamforming algorithm does not sacrifice “much throughput
performance.’” In other words, the algorithm sacrifices
throughput performance, as Khoj[astepour] admits that it has a
negative effect on the amount of user-generated data that can be
sent to the NodeB. Hence, Examiner’s argument is erroneous.
Khoj[astepour]’s reduction scheme degrades throughput
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performance. Therefore, Khoj[astepour] teaches away from a
transmission rank, or precoding matrix, “feedback reduction
scheme” as required by the independent claims.
Br. 16–17 (internal citations and emphasis omitted).
We find Appellants’ contentions unpersuasive. Initially, we note that
Appellants contentions regarding Khojastepour teaching away are not
relevant to anticipation and, therefore, unpersuasive. See Seachange Intern.,
Inc. v. C-COR, Inc., 413 F.3d 1361, 1380 (Fed. Cir. 2005). Although
Appellants’ Specification does not expressly define the terms “transmission
rank feedback reduction scheme” nor “precoding matrix feedback reduction
scheme,” it does explain that the premises of feedback schemes, i.e., a
transmission rank reduction scheme and a precoding matrix feedback
reduction scheme, include “significantly reducing the uplink feedback
overhead and reducing the computational complexity in deriving a preferred
rank and PMI.” Spec. ¶ 21. Therefore, we find that the feedback
limitations, reasonably construed, refer to a scheme for providing feedback
that reduces the amount of feedback overhead and computational
complexity.
Khojastepour teaches that the base station obtains feedback, including
a transmission rank information and a beamforming or precoding matrix
index, from user equipment on a per-chunk basis. Khojastepour Fig. 2, ¶ 67.
Khojastepour further teaches “to further reduce the feedback from the UEs,
each UE can choose to send information about only the first few of its ‘best’
chunks rather than all of them.” Khojastepour ¶ 67. Khojastepour also
teaches that the feedback scheme “allows for a considerable reduction in
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computational complexity as well as the memory requirement of the UE.”
Khojastepour ¶ 71. As such, Khojastepour teaches the feedback limitations.
Accordingly, we are not persuaded that the Examiner erred in
rejecting claim 1 or independent claims 16, 31, and 46, not argued
separately. See Br. 11–17.
CLAIM 2
Appellants contend that Khojastepour does not teach that “an update
rate of the transmission rank selection is a function of a receiver speed,” as
recited in claim 2. Br. 17. Appellants contend that “[o]ne of ordinary skill
in the art recognizes that the word ‘speed’ is related to the velocity of the UE
[user equipment], not the speed of its processing circuits.” Br. 17 (emphasis
omitted).
We do not find Appellants’ contentions persuasive. During
examination of a patent application, claim terms are given their broadest
reasonable interpretation, consistent with the specification, as they would be
understood by one of ordinary skill in the art. In re Buszard, 504 F.3d 1364,
1367 (Fed. Cir. 2007); In re Am. Acad. of Sci. Tech Ctr., 367 F.3d 1359,
1364 (Fed. Cir. 2004). An inventor is “free to define the specific terms used
to describe his or her invention,” but “this must be done with reasonable
clarity, deliberateness, and precision. In re Paulsen, 30 F.3d 1475, 1480
(Fed. Cir. 1994). In this case, Appellants’ Specification does not provide a
definition of the term “receiver speed.” The Examiner interprets the term
“receiver speed” as “the speed of the processor.” Ans. 19. The common
dictionary meaning of the term “speed” includes “[t]he rate or a measure of
the rate of motion.” The American Heritage Dictionary, 1174 (Second
College Edition 1982). As such, and giving the term its broadest reasonable
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interpretation, we find the Examiner’s interpretation of the term “receiver
speed” — the rate at which the receiver’s processing circuits process data —
to be reasonable. Khojastepour teaches that an update rate of the
transmission rank selection is based on a processing loop of the receiver.
Khojastepour, Fig. 7, ¶ 78. Khojastepour, therefore, teaches that an update
rate of the transmission rank selection is a function of a speed of the
receiver’s processor. As such, we find that Khojastepour teaches the
disputed limitation.
Accordingly, we are not persuaded that the Examiner erred in
rejecting claim 2 or claims 17, 32, and 47, argued together with claim 2. See
Br. 17.

CLAIM 3
Appellants contend that Khojastepour does not teach that “the
transmission rank selection is based on a receiver geometry,” as recited in
claim 3. Br. 18. Appellants contend:
One of ordinary skill in the art recognizes that the word
“geometry” is related to the propagation characteristics of the
UE wireless channel (such as distance, height above terrain, or
geographical impairment), not the physical size of the receiver,
its orientation or its antenna configuration. The instant
specification ([0038]; Fig. 2) teaches an example of where the
UE would operate at a low rank: “For example, if the UE’s
geometry is under a pre-defined lower threshold (which could
be designed offline), if the UE’s distance to the serving Node B
is larger than a threshold or the UE is experiencing a less
favorable channel and hence more likely to be operating at a
low rank.”
Br. 18 (emphasis omitted).
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We do not find Appellants’ contentions persuasive. As discussed
supra, during examination, pending claims are given their broadest
reasonable construction consistent with the specification (Buszard, 504 F.3d
at 1367) and an inventor is “free to define the specific terms used to describe
his or her invention,” but “this must be done with reasonable clarity,
deliberateness, and precision (Paulsen, 30 F.3d at 1480). In this case,
Appellants’ Specification does not expressly define the term “receiver
geometry.” The Examiner interprets the term “receiver geometry” as “the
number of antennas” of the receiver. Ans. 20. Appellants’ Specification
teaches that “the transmission rank selection is based on a receiver geometry
with respect to the multiple antennas that provide the transmissions.” Spec.
¶ 52. As such, we find the Examiner’s interpretation is consistent with
Appellants’ Specification and, therefore, reasonable. Further, the example
cited by Appellants is merely an example and does not serve to further limit
the claim. See In re Van Geuns, 988 F.2d 1181, 1184 (Fed. Cir. 1993)
(“[L]imitations are not to be read into the claims from the specification.”).
Khojastepour teaches that, for a multiple-antenna system, the transmission
rank selection is based on a number of receive and transmit antennas.
Khojastepour ¶ 34. As such, Khojastepour teaches that the transmission
rank selection is based on a receiver geometry.
Accordingly, we are not persuaded that the Examiner erred in
rejecting claim 3 or claims 18, 33, and 48, argued together with claim 3. See
Br. 18.

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CLAIM 4
Appellants contend that Khojastepour does not teach that “the
transmission rank selection is restricted to a subset of available transmission
ranks that is transmission-configured or receiver-configured,” as recited in
claim 4. Br. 18. Appellants argue that “Khoj[astepour] fails to teach
transmission rank selection restricted to a subset of available transmission
ranks.” Id. (emphasis omitted).
We find Appellants contentions unpersuasive. Appellants merely
recite the limitations of claim 4 and assert that Khojastepour does not teach
these limitations. See Br. 18. 37 C.F.R. § 41.37(c)(1)(vii) requires more
substantive arguments in an appeal brief than a mere recitation of the claim
elements and a naked assertion that the corresponding elements were not
found in the prior art. See In re Lovin, 652 F.3d 1349, 1357 (Fed. Cir.
2011).
Accordingly, we are not persuaded that the Examiner erred in
rejecting claim 4 or claims 19, 34, and 49, argued together with claim 4. See
Br. 18.

CLAIM 5
Appellants contend that the Examiner err in finding that Khojastepour
teaches that “the transmission rank selection is a differential rank that
corresponds to a difference between a current transmission rank and a
reference transmission rank,” as recited in claim 5. Br. 19. Appellants argue
that “the word ‘differential’ is related to the transmission of a difference
quantity, in this case an increase by one or a decrease by one of an index.”
Id. Appellants further argue that “‘[d]ifferential’ has no relationship to
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starting a loop at the highest rank and decrementing by k-1,” as taught by
Khojastepour. Id.
We do not find Appellants’ contentions persuasive. As discussed
supra, during examination, pending claims are given their broadest
reasonable construction consistent with the specification (Buszard, 504 F.3d
at 1367) and an inventor is “free to define the specific terms used to describe
his or her invention,” but “this must be done with reasonable clarity,
deliberateness, and precision (Paulsen, 30 F.3d at 1480). In this case,
Appellants’ Specification does not expressly define the term “differential
rank.” The Examiner interprets the term “differential rank” as a
transmission rank that is selected by decrementing a previous transmission
rank by one. Ans. 21. The term “differential” has the common dictionary
meaning “[o]f, pertaining to, or showing a difference.” The American
Heritage Dictionary, 395. As such, we find the Examiner’s interpretation
reasonable. Khojastepour teaches a transmission rank selection (k-1) that is
based on decrementing a reference transmission (k) rank by one.
Khojastepour, Fig. 5, ¶ 75. Khojastepour, therefore, discloses the disputed
limitation. We note for emphasis only that claim 5 does not require the
claimed differential rank to be a difference quantity — e.g., “+1,” “-1,” etc.
— as argued by Appellants. See Br. 19, Claims Appendix. As such,
Appellants’ arguments are not commensurate with the scope of claim 5, and
thus, for that reason, do not demonstrate error in the Examiner’s rejection of
claim 5. See In re Self, 671 F.2d 1344, 1348 (CCPA 1982) (limitations not
appearing in the claims cannot be relied upon for patentability).
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Accordingly, we are not persuaded that the Examiner erred in
rejecting claim 5 or claims 20, 35, and 50, argued together with claim 5. See
Br. 19.

CLAIM 6
Appellants contend that Khojastepour does not teach that “the
reference transmission rank includes the last transmission rank selection,” as
recited in claim 6. Br. 20. Appellants contend:
Moreover, Examiner contends that Khoj[astepour]
teaches the “reference rank is the last transmission rank (K-l), K
being the last transmission rank.” Examiner’s statement is true
only for operations within the loop of Khoj[astepour] Fig. 5.
But, one of ordinary skill in the art recognizes that the word
“last” is synonymous with “previous”, its the previous value of
transmission rank. If Khoj[astepour]’s loop calculation is
exercised, then the output is one less rank. As such,
Khoj[astepour] fails to teach “the reference transmission rank
includes the last transmission rank” as required by claim 6.
Br. 20 (emphasis omitted).
We do not find Appellants’ contentions persuasive. In this case,
Appellants’ Specification does not expressly define the term “last
transmission rank.” The Examiner interprets the term “last transmission
rank” as including a highest, or last, transmission rank as opposed to a
lowest, or first, transmission rank. Ans. 21. The common dictionary
meaning of the term “last” includes “[b]eing, coming, or placed after all
others.” The American Heritage Dictionary, 715. As such, we find the
Examiner’s interpretation reasonable. Khojastepour teaches determining a
transmission rank using a processing loop that begins with a highest possible
transmission rank — e.g., a reference transmission rank. Khojastepour ¶ 74.
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Khojastepour further teaches that the transmission rank is decremented (e.g.,
transmission rank k-1) and the processing loop is repeated until the point
when the sum rate supported by the channel does not increase. Khojastepour
¶75–76. Khojastepour, therefore, teaches that, at least in the case where a
transmission rank k-1 corresponds to the maximum sum rate and, therefore,
the selected transmission rank, the reference transmission rank, k, includes
the last transmission rank.
Accordingly, we are not persuaded that the Examiner erred in
rejecting claim 6 or claims 21, 36, and 51, argued together with claim 6. See
Br. 20.

CLAIM 7
Appellants contend that Khojastepour does not teach that “the
precoding matrix selection corresponds to a single precoding matrix for a
frequency sub-band that contains at least two adjacent resource blocks,” as
recited in claim 7. Br. 20. Appellants contend that Khojastepour “fails to
mention a frequency sub-band” and, therefore, fails to teach the limitations
recited in claim 7. Br. 21 (emphasis omitted). Appellants contend that:
[The] Examiner contends that “Khoj shows base stations
utilize OFDM wireless MIMO communication with feedback
from the UE and the communication via streams and channels
in ofdm which are equated to the frequency sub-bands.”
Examiner’s statement is merely supposition with no basis in
fact.
Br. 21 (emphasis omitted).
We do not find Appellants contentions persuasive. Khojastepour
teaches that “in order to achieve the best performance over an OFDM-based
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downlink with reasonable feedback, the available sub-carriers are divided
into chunks of adjacent tones.” Khojastepour ¶ 67. Further, as admitted in
Appellants’ Background section of the Specification, “[i]n orthogonal
frequency division multiple access (OFDMA) communication systems, the
total bandwidth [e.g., available sub-carriers] is divided into non-overlapping
frequency blocks [e.g., chunks of adjacent tones] also called resource blocks.
Spec. ¶ 4. Khojastepour, therefore, discloses dividing the available sub-
carriers into frequency sub-bands that contain at least two adjacent resource
blocks. Khojastepour further teaches that “the precoder, i.e., beamforming
matrix, chosen for a tone usually is also the best precoder for the adjacent
tones” and that “[i]t is possible to optimally design and also select wideband
precoders for the set of parallel channels, i.e., all tones in the chunk.”
Khojastepour ¶ 67. As such, Khojastepour discloses selecting a precoding
matrix that corresponds to a single precoding matrix for a frequency sub-
band that contains at least two adjacent resource blocks.
Accordingly, we are not persuaded that the Examiner erred in
rejecting claim 7 or claims 22, 37, and 52, argued together with claim 7. See
Br. 21.

CLAIM 8
Appellants contend that Khojastepour does not teach that “the
precoding matrix selection is restricted to a subset of available precoding
matrices that is transmission-configured or receiver-determined,” as recited
in claim 8. Br. 21. According to Appellants, Khojastepour teaches
determination of a precoding matrix using successive beamforming
techniques. Br. 22 (citing Khojastepour ¶ 71). Appellants contend that
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Khojastepour fails to teach a selection of a precoding matrix from a subset of
available matrices because Khojastepour teaches modifying an initial matrix
column by column. Br. 21.
We find Appellants’ contentions persuasive. Khojastepour teaches
that the precoding matrix is determined based on a set of quantized vectors.
Khojastepour ¶ 77. Khojastepour further teaches that the set of quantized
vectors is determined by performing, within nested loops, an inner product
calculation between eigenvectors of the channel and the corresponding
vectors from the codebook. Id. As such, Khojastepour fails to teach that the
precoding matrix is selected from a subset of available precoding matrices.
Accordingly, we do not sustain the rejection of (1) claim 8; (2) claims
23, 38, and 53, argued together with claim 8; (3) claims 9, 24, 39, and 54,
which recite similar limitations; and claims 10–13, 25–28, 40–43, and 55–
58, which depend variously from claims 9, 24, 39, and 54. See Br. 22–24.

CLAIM 14
Appellants contend that Khojastepour does not teach that “the
precoding matrix selection is a differential precoding matrix that
corresponds to a difference between a current precoding matrix and a
reference precoding matrix,” as recited in claim 14. Br. 25. Appellants
contend that Khojastepour teaches that the precoding matrix is selected
based on the inner product calculation between the eigenvectors of the
channel and the corresponding vectors from the codebook and the
determined inner product does not correspond to a difference between a
current precoding matrix and a reference precoding matrix. Br. 25.
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The Examiner finds “Khoj[astepour] shows the precoding matrix is
selected and performed within a nested loop (i.e. based on difference
between current and last) and that the selection is done by successive
beamforming which [is] a form of differential precoding matrices.” Ans. 25
(citing Khojastepour, Fig. 6; ¶ 77).
We find Appellants’ contentions persuasive. As discussed supra,
Khojastepour teaches that the precoding matrix is determined based on a set
of quantized vectors and that the set of quantized vectors is determined by
performing, within nested loops, an inner product calculation between
eigenvectors of the channel and the corresponding vectors from the
codebook. Khojastepour ¶ 77. We agree with Appellants that calculating an
inner product does not correspond to calculating a difference between a
current and a last, as found by the Examiner. See Br. 25.
Accordingly, we do not sustain the rejection of claim 14 and claims
29, 44, and 59, argued together with claim 14. See Br. 25.

CLAIM 15
Appellants contend that Khojastepour does not teach that “the
precoding matrix selection corresponds to a time domain representation or a
frequency domain representation,” as recited in claim 15. Br. 25–26.
Appellants contend that Khojastepour fails to teach any variables that are
functions of frequency or identify any processing blocks that are performed
in the frequency domain. Br. 26.
We do not find Appellants’ contentions persuasive. The Examiner
finds, and we agree, Khojastepour teaches an OFDM (orthogonal frequency-
division multiplexing) wireless MIMO (multiple-input, multiple-output)
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communication system where the available sub-carriers are divided into
chunks of adjacent tones — e.g., a frequency domain representation — and a
feedback signal, including the rank information, the beamforming matrix
index, and channel quality indices, are provided on a per-chunk basis. See
Ans. 26 (citing Khojastepour ¶ 65; Fig. 2). As discussed supra,
Khojastepour also teaches that “the precoder, i.e., beamforming matrix,
chosen for a tone usually is also the best precoder for the adjacent tones” and
that “[i]t is possible to optimally design and also select wideband precoders
for the set of parallel channels, i.e., all tones in the chunk.” Khojastepour
¶ 67. As such, Khojastepour teaches the disputed limitation.
Accordingly, we are not persuaded that the Examiner erred in
rejecting claim 15 or claims 30, 45, and 60, argued together with claim 15.
See Br. 17.

DECISION
As such, we affirm the Examiner’s rejection of claims 1–7, 15–22,
30–37, 45–52, and 60; and we reverse the Examiner’s rejection of claims 8–
14, 23–29, 38–44, and 53–59.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(1)(iv).

AFFIRMED-IN-PART

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