Ex Parte Ji

Patent Trial and Appeal Board

Jun 2, 2014

11760398 (P.T.A.B. Jun. 2, 2014)

UNITED STATES PATENT AND TRADEMARK OFFICE
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BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

Ex parte BAOWEI JI
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Appeal 2012-000610
Application 11/760,398
Technology Center 2600
____________

Before JOSEPH F. RUGGIERO, JOHN A. JEFFERY, and
CARLA M. KRIVAK, Administrative Patent Judges.

JEFFERY, Administrative Patent Judge.

DECISION ON APPEAL
Appellant appeals under 35 U.S.C. § 134(a) from the Examiner’s
decision to reject claims 1-19. Claim 20 has been indicated as containing
allowable subject matter. Ans. 3.1 We have jurisdiction under 35 U.S.C.
§ 6(b). We affirm.

STATEMENT OF THE CASE
Appellant’s invention transmits a beacon signal to facilitate quick
beacon detection and protect a low-power device in a wireless network by

1 Throughout this opinion, we refer to (1) the Appeal Brief filed February
28, 2011 (“App. Br.”); (2) the Examiner’s Answer mailed May 12, 2011
(“Ans.”); and (3) the Reply Brief filed July 8, 2011 (“Reply Br.”).
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(1) spreading each symbol of a beacon message with a fixed-length
pseudorandom (PN) code, and (2) transmitting the beacon signal without a
corresponding pilot signal. See generally Abstract. Claims 1 and 7 are
illustrative:
1. A method for transmitting a beacon signal to facilitate
quick beacon detection and protect a low-power device in a
wireless network, comprising:
spreading each symbol of a beacon message with a fixed-
length pseudorandom (PN) code to generate the beacon signal;
and
transmitting the beacon signal without a corresponding
pilot signal.
7. A method for detecting a beacon signal operable to protect
a low-power device at a receiver in a wireless network,
comprising:
detecting an energy level of a received signal by
accumulating the energy of the received signal for a
predetermined period of time to generate an accumulated signal
value;
comparing the accumulated signal value to a detection
threshold; and
identifying the received signal as the beacon signal when
the accumulated signal value is greater than the detection
threshold.

THE REJECTIONS
The Examiner rejected claim 1 under 35 U.S.C. § 102(e) as
anticipated by Neugebauer (US 2005/0281318 A1; pub. Dec. 22, 2005).
Ans. 5.
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The Examiner rejected claims 2, 3, and 5 under 35 U.S.C. § 103(a) as
unpatentable over Neugebauer and Bhatoolaul (US 2001/0046864 A1; pub.
Nov. 29, 2001). Ans. 5-6.
The Examiner rejected claim 4 under 35 U.S.C. § 103(a) as
unpatentable over Neugebauer, Bhatoolaul, and Shvodian (US
2004/0013127 A1; pub. Jan. 22, 2004). Ans. 7.
The Examiner rejected claim 6 under 35 U.S.C. § 103(a) as
unpatentable over Neugebauer and Shvodian. Ans. 7-8.
The Examiner rejected claims 7-10 and 13-16 under 35 U.S.C.
§ 103(a) as unpatentable over Laroia (US 2005/0233746 A1; pub. Oct. 20,
2005) and Liang (US 6,496,572 B1; iss. Dec. 17, 2002). Ans. 8-11.
The Examiner rejected claims 11 and 17 under 35 U.S.C. § 103(a) as
unpatentable over Laroia and Watanabe (US 2005/0185628 A1; pub. Aug.
25, 2005). Ans. 11.
The Examiner rejected claims 12 and 18 under 35 U.S.C. § 103(a) as
unpatentable over Laroia and Bevis (US 2004/0246476 A1; pub. Dec. 9,
2004). Ans. 12.
The Examiner rejected claim 19 under 35 U.S.C. § 103(a) as
unpatentable over Laroia and Goren (US 2002/0098852 A1; July 25, 2002).
Ans. 12-13.

THE ANTICIPATION REJECTION
The Examiner finds that Neugebauer discloses every recited element
of claim 1 including (1) spreading each symbol of a beacon message with a
fixed-length PN code to generate a beacon signal in light of the teachings of
paragraphs 0030, 0032, and 0039, and (2) transmitting the beacon signal
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without a corresponding pilot signal. Ans. 5, 13-16. According to the
Examiner, the transmission limitation is met in light of Neugebauer’s
transmitting a “beacon or pilot signal” that is said to refer to the same signal.
Ans. 13-14.
Appellant argues that Neugebauer does not spread each symbol of a
beacon message with a fixed-length PN code to generate a beacon signal, let
alone transmit this signal without a corresponding pilot signal. App. Br. 16-
18; Reply Br. 2-3. According to Appellant, the fact that Neugebauer’s
spreading code cycle period is equal to the encoded symbol rate does not
necessarily mean that each symbol of a beacon message is spread with a
fixed-length PN code as claimed. App. Br. 18; Reply Br. 2-3.

ISSUE
Under § 102, has the Examiner erred in rejecting claim 1 by finding
that Neugebauer (1) spreads each symbol of a beacon message with a fixed-
length PN code to generate a beacon signal, and (2) transmits that signal
without a corresponding pilot signal?

ANALYSIS
We sustain the Examiner’s rejection of claim 1. In Neugebauer’s
Figure 1, input data 100 includes a pilot or beacon signal encoded with a
pseudonoise code and modulated for transmission over a multipath channel.
Neugebauer ¶ 0030. To this end, the transmitter’s pseudonoise code
generator 103 produces a stream of bits that are combined with the encoded
data stream from encoder 101. Id. ¶ 0032. Notably, the pseudonoise code
stream rate is usually a multiple of the input data stream rate (e.g., 10:1). Id.
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Thus, mixer 102 produces a wideband combined signal by combining the
higher speed (wideband) pseudonoise code with the lower speed
(narrowband) input data. Id.
This combination of data streams would result in spreading each
symbol of the input data stream with a PN code by virtue of their mutual
data-rate relationship which, in one example, is 10:1. In this particular
example, for every one bit of the low-speed input data, there are ten bits of
high-speed pseudonoise code in the combined signal. Therefore, regardless
of whether Neugebauer’s spreading code cycle equaling the encoded symbol
rate discussed in connection with the embodiment of paragraph 0039 and
Figure 3 supports the Examiner’s or Appellant’s respective positions (App.
Br. 18; Reply Br. 2-3; Ans. 15-16), nothing in the claim precludes the
inherent spreading of each beacon message symbol resulting from
combining the pseudonoise code and input data streams noted above.
We also see no error in the Examiner’s interpreting Neugebauer’s
“pilot or beacon signal” in paragraph 0030 as the same signal with alternate
names—an interpretation that Appellant acknowledges. See Ans. 13-14;
App. Br. 17. Although Neugebauer’s transmitted beacon signal is also a
pilot signal under this interpretation, it is nonetheless only one signal: there
is not another or corresponding pilot signal transmitted with this beacon
signal as the Examiner correctly indicates. Ans. 14.
Therefore, we are not persuaded that the Examiner erred in rejecting
claim 1.

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THE OBVIOUSNESS REJECTION OVER NEUGEBAUER AND
BHATOOLAUL

We also sustain the Examiner’s obviousness rejection of claim 5
reciting, in pertinent part, appending a message separation indicator to the
spread beacon message to generate a beacon data block, the beacon signal
comprising plural repeating beacon data blocks. Despite Appellant’s
arguments to the contrary (App. Br. 19-20), nothing in the claim precludes
the space-based indicator between repeated preamble transmissions at
predetermined intervals as the Examiner indicates. Ans. 6, 16-17 (citing
Bhatoolaul ¶¶ 0027, 0029; Fig. 1). This period between repeated
transmission intervals not only indicates the separation between these
intervals, but also separates the overall beacon signal into plural repeating
data blocks.
Therefore, we are not persuaded that the Examiner erred in rejecting
representative claim 5, and claims 2 and 3 not argued separately with
particularity.

THE OBVIOUSNESS REJECTION OVER LAROIA AND LIANG
Regarding claim 7, the Examiner finds that Laroia detects a beacon
signal by (1) detecting a received signal’s energy level; (2) comparing the
detected energy level to a detection threshold; and (3) identifying the
received signal as the beacon signal when the detected energy level is
greater than the threshold. Ans. 8-9. Although the Examiner acknowledges
that Laroia does not expressly disclose that the energy-level detection
accumulates energy for a predetermined time period to generate an
accumulated signal value that is compared to the detection threshold, the
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Examiner cites Liang for teaching this feature in concluding that the claim
would have been obvious. Ans. 8-9, 18-19.
Appellant argues that Liang does not teach or suggest accumulating
energy of a received signal to generate an accumulated signal value, let
alone compare this value to a threshold to identify a beacon signal as
claimed. Rather Appellant asserts, Liang performs a series of correlations
for sequences of signal samples, and compares the correlations with
respective thresholds to determine whether associated conditions are met.
App. Br. 22-24; Reply Br. 3-4. Appellant argues various other recited
limitations summarized below.

ISSUES
Under § 103, has the Examiner erred by finding that Laroia and Liang
collectively would have taught or suggested:
(1)(a) detecting a received signal’s energy level by accumulating the
energy of the received signal for a predetermined time period to generate an
accumulated signal value that is compared to a detection threshold; and (b)
identifying the received signal as the beacon signal when the accumulated
signal value is greater than the threshold as recited in claim 7; and
(2) the limitations of claims 8-10 and 14-16?

ANALYSIS
Claims 7 and 13
We begin by noting that the Examiner’s particular findings regarding
Laroia are undisputed; rather, Appellant’s arguments are directed principally
to the Examiner’s reliance on Liang. See App. Br. 22-24; Reply Br. 3-4.
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These undisputed findings from Laroia are notable, for the Examiner
finds that Laroia discloses many of the aspects of the detecting, comparing,
and identifying steps of independent method claim 7, except that the
comparing and identifying steps are performed with respect to a detected
energy level instead of an “accumulated signal value” as claimed. See Ans.
8-9 (citing Laroia ¶¶ 0014, 0136).
Leaving aside the fact that Laroia’s energy-level detection would
accumulate energy for some time period and generate an associated signal
value, we nonetheless see no error in the Examiner’s reliance on Liang for at
least suggesting that accumulating energy of a received signal for a
predetermined time period and generating an associated accumulated signal
value for comparison would have been obvious. Appellant does not
persuasively rebut the Examiner’s finding that Liang’s call-waiting tone
detector functionality accumulates energy of the associated tone over some
predetermined time period in connection with the particular samples that are
summed to obtain the corresponding correlations as the Examiner indicates.
Ans. 9, 19 (citing col. 5, l. 47–col. 6, l. 57; Fig. 4).
Nor does Appellant persuasively rebut the Examiner’s position that
combining these teachings from Liang with Laroia renders the claimed
invention obvious. Appellant’s arguments regarding Liang’s individual
shortcomings (see App. Br. 22-24; Reply Br. 3-4) do not show
nonobviousness where, as here, the rejection is based on the references’
collective teachings. See In re Merck & Co., Inc., 800 F.2d 1091, 1097
(Fed. Cir. 1986).
Therefore, we are not persuaded that the Examiner erred in rejecting
representative claim 7, and claim 13 not argued separately with particularity.
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Claims 8-10 and 14-16
We also sustain the Examiner’s rejection of dependent claims 8-10
reciting, in pertinent part, detecting the received signal’s energy level by
correlating symbols of the received signal, and dependent claims 14-16
reciting a detector operable to perform this function.
First, Appellant’s arguments regarding the cited prior art’s alleged
shortcomings regarding independent claims (App. Br. 24) are unpersuasive
for the reasons previously discussed. Second, apart from merely alleging
that the cited references do not disclose or suggest the reciting detection and
symbol correlation limitations (id.), Appellant does not squarely address—
let alone persuasively rebut—the Examiner’s findings from Laroia and
Liang in this regard. Ans. 9-11, 19-20.
Therefore, we are not persuaded that the Examiner erred in rejecting
claims 8-10 and 14-16.

THE REMAINING OBVIOUSNESS REJECTIONS
We also sustain the Examiner’s obviousness rejections of claims 4, 6,
11, 12, and 17-19. Ans. 7-8, 11-13. Despite nominally arguing these claims
separately, Appellant reiterates similar arguments made in connection with
the independent claims and allege that the additional cited references fail to
cure those purported deficiencies. App. Br. 20-21, 24-26. We are not
persuaded by these arguments, however, for the reasons previously
discussed.

CONCLUSION
The Examiner did not err in rejecting claims 1-19 under § 103.
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DECISION
The Examiner’s decision rejecting claims 1-19 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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