Ex Parte Zangi

Patent Trial and Appeal Board

Sep 16, 2014

11668185 (P.T.A.B. Sep. 16, 2014)

UNITED STATES PATENT AND TRADEMARK OFFICE
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.
11/668,185 01/29/2007 Kambiz C. Zangi 4015-5574 3397
24112 7590 09/16/2014
COATS & BENNETT, PLLC
1400 Crescent Green, Suite 300
Cary, NC 27518
EXAMINER
MIAN, OMER S
ART UNIT PAPER NUMBER
2461
MAIL DATE DELIVERY MODE
09/16/2014 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 PATENT TRIAL AND APPEAL BOARD
_____________

Ex parte KAMBIZ C. ZANGI
_____________

Appeal 2012-004104
Application 11/668,185
Technology Center 2400
______________

Before ROBERT E. NAPPI, JEAN R. HOMERE, and BETH Z. SHAW,
Administrative Patent Judges.

NAPPI, Administrative Patent Judge.

DECISION ON APPEAL
This is a decision on appeal under 35 U.S.C. § 134(a) of the rejection
of claims 1 through 30.
We affirm.

INVENTION
The invention is directed to a method of estimating signal impairment
correlations across antennas in a multi-antenna receiver using data values
rather than pilot values in a multi-frequency signal received at each of the
receiver antennas. See Abstract of Appellant’s Specification. Claim 1 is
illustrative of the invention and reproduced below:

Appeal 2012-004104
Application 11/668,185

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1. A method of estimating impairment correlation between
receiver antennas of an Orthogonal Frequency Division
Multiplexing (OFDM) receiver, the method comprising:
generating channel estimates based on pilot sub-carriers
in an OFDM signal received at each of two or more receiver
antennas;
determining received signal correlation estimates for the
OFDM signal across the receiver antennas based on data sub-
carriers in the OFDM signal; and
calculating impairment correlation estimates for the
OFDM signal across the receiver antennas based on the channel
estimates and the signal correlation estimates.

REJECTIONS AT ISSUE
The Examiner has rejected claims 1 through 8, 10 through 12, 14
through 24, 26, and 28 through 30 under 35 U.S.C. § 103(a) as unpatentable
over Melzer (US 2007/0147536 A1, June 28, 2007) and Bang (US 7,477,190
B2, Jan. 13, 2009). Answer 4–17.1
The Examiner has rejected claim 13 and 27 under 35 U.S.C. § 103(a)
as unpatentable over Melzer, Bang, and Tirkkonen (US 2007/0082692 A1,
Apr. 12, 2007). Answer 17–18.
The Examiner has rejected claim 9 and 25 under 35 U.S.C. § 103(a) as
unpatentable over Melzer, Bang, and Heikkila (US 2007/0002982 A1, Jan.
4, 2007). Answer 18–20.

1 Throughout this opinion we refer to the Appeal Brief dated August 26,
2011, Reply Brief dated December 16, 2011, and the Examiner’s Answer
mailed on October 25, 2011.
Appeal 2012-004104
Application 11/668,185

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ISSUE
Appellant argues on pages 8 through 10 of the Appeal Brief and pages
4 through 9 of the Reply Brief that the Examiner’s rejection based upon
Melzer and Bang is in error.
These arguments present us with the issues:
a) Did the Examiner err in finding the combination of Melzer and
Bang teaches calculating impairment correlation estimates for the
OFDM signal across the receiver antennas based on the channel
estimates based upon pilot sub-carriers, and signal correlation
estimates based upon data sub-carriers?
b) Did the Examiner provide sufficient rationale to demonstrate the
skilled artisan would have combined Melzer and Bang?

ANALYSIS
The Examiner has provided a comprehensive response to Appellant’s
arguments. We have reviewed the Examiner’s response and concur.
Appellant’s arguments directed to the first issue focus on the
teachings of Bang. Specifically, Appellant argues that although Bang
teaches using data subcarriers to determine a covariance matrix (which the
Examiner equates to the claimed correlation estimates), Bang does not teach
using the covariance matrix along with channel estimates to compute
impairment correlation estimates. Brief 8. We are not persuaded by
Appellant’s arguments. The Examiner finds the claimed signal correlation
estimates are taught by the Bang’s interference-plus noise covariance matrix,
and that the claimed impairment correlation estimates are taught by Bang’s
covariance matrix. Answer 21. The Examiner then shows that Bang’s
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Application 11/668,185

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Figures 2 through 5 depict calculating the interference-plus noise covariance
matrix (item 341, Figure 5) based upon the channel estimate (item 331,
Figure 4) and the covariance matrix (item 311, Figure 2). Answer 22–24.
We have reviewed the evidence cited by the Examiner and concur with the
Examiner’s findings. While the covariance matrix is used in several
processes prior to the calculating the impairment covariance matrix, Bang
nonetheless teaches that the calculation is based upon the covariance matrix.
Thus, Appellant’s arguments directed to the first issue have not persuaded us
of error in the Examiner’s rejection of representative claim 1.
Appellant’s arguments directed to the second issue assert that Bang’s
beam forming teachings does not relate to the teachings of Melzer and as
such, the rejection is improper. Brief 9–10. In the Reply Brief, Appellant
further argues the combination would change the principal operation of
Melzer, as Melzer is concerned with mobile stations and Bang is concerned
with base stations. Reply Brief 7–9. In response to Appellant’s arguments,
the Examiner finds that Bang teaches a way to eliminate interference and
maximize signal to interference ratio. Answer 5–6, 25 (citing Bang, col. 4,
ll. 8–14, col. 2, ll. 17–20). Based upon this finding, the Examiner reasons
the skilled artisan properly combined the teachings of the references.
Answer 25. Further, the Examiner finds that both references are directed to
computing the signal and noise-plus-interference ratio. Answer 26. We
concur with the Examiner’s findings. Additionally, we disagree with
Appellant’s argument on page 8 of the Reply Brief, directed to Melzer’s
paragraph 19 teachings, as paragraph 19 teaches the functions associated
with items 102 and 106 (which in one embodiment are mobile station and
base station respectively) may be applied different devices such as a station
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Application 11/668,185

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(STA), i.e., the functions of item 106 are not limited to a mobile station.
Thus, Appellant’s arguments directed to the second issue have not persuaded
us of error in the Examiner’s rejection of claim 1. Accordingly, we sustain
the Examiner’s rejection of claims 1 through 8, 10 through 12, 14 through
24, 26, and 28 through 30 based upon Melzer and Bang.
Appellant has not presented separate arguments directed to the
rejections of claims 9, 13, 25, and 27. Accordingly, we similarly sustain the
Examiner’s rejection of these claims.

DECISION
The decision of the Examiner to reject claims 1 through 30 is
affirmed.
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

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