Ex Parte Neilson

Patent Trial and Appeal Board

Jan 16, 2014

11614325 (P.T.A.B. Jan. 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.
11/614,325 12/21/2006 David T. Neilson Neilson 24 9186
46850 7590 01/17/2014
MENDELSOHN, DRUCKER, & DUNLEAVY, P.C.
1500 JOHN F. KENNEDY BLVD., SUITE 312
PHILADELPHIA, PA 19102
EXAMINER
CURS, NATHAN M
ART UNIT PAPER NUMBER
2636
MAIL DATE DELIVERY MODE
01/17/2014 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 DAVID T. NEILSON
_____________

Appeal 2011-005701
Application 11/614,325
Technology Center 2600
______________

Before BRADLEY W. BAUMEISTER, DAVID M. KOHUT, and
ANDREW J. DILLON, Administrative Patent Judges.

KOHUT, Administrative Patent Judge.

DECISION ON APPEAL

Appeal 2011-005701
Application 11/614,325

2
This is a decision on appeal under 35 U.S.C. § 134(a) of the
Examiner’s Final Rejection of claims 1-24. We have jurisdiction under
35 U.S.C. § 6(b).
We reverse the Examiner’s rejections of these claims.

INVENTION
The invention is directed to a method and optical transmitter that use
half-rate electrical signals in order to generate full-rate optical duobinary
signals. Spec. 2. Claim 1 is illustrative of the invention and is reproduced
below:
1. A method of generating an optical duobinary signal,
comprising:
applying a first data stream having a first bit rate to drive a
first arm of an optical modulator;
misaligning a second data stream with respect to the first data
stream by one half of a bit period corresponding to the first bit
rate to produce a misaligned data stream, wherein the second
data stream is synchronized with the first data stream and has
the first bit rate; and
applying said misaligned data stream to drive a second arm
of the optical modulator wherein:
the optical modulator is adapted to modulate an optical
beam based on said applied data streams to generate the optical
duobinary signal; and
the step of misaligning comprises delaying the second
data stream with respect to the first data stream by a delay time
greater than a bit-period duration corresponding to the first bit
rate.

REFERENCES
Davies US 5,999,300 Dec. 7, 1999

Mizuhara US 6,522,438 B1 Feb. 18, 2003
Appeal 2011-005701
Application 11/614,325

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Mino US 2007/0154137 A1 July 5, 2007

Ho US 7,280,767 B1 Oct. 9, 2007

REJECTIONS AT ISSUE
Claims 1-20 and 24 are rejected under 35 U.S.C. § 112, second
paragraph, as being indefinite for failing to particularly point out and
distinctly claim the subject matter which applicant regards as the invention.
Ans. 4.
Claims 1-6, 9-16, and 20 are rejected under 35 U.S.C. § 103(a) as
obvious over the combination of Ho and Mizuhara. Ans. 5-10.
Claims 7, 8, 17, and 18 are rejected under 35 U.S.C. § 103(a) as
obvious over the combination of Ho, Mizuhara, and Davies. Ans. 10-12.
Claim 19 is rejected under 35 U.S.C. § 103(a) as obvious over the
combination of Ho, Mizuhara, and Mino. Ans. 12-13.
Claims 21-23 are rejected under 35 U.S.C. § 103(a) as obvious over
the combination of Ho and Davies. Ans. 13-14.
Claim 24 is rejected under 35 U.S.C. § 103(a) as obvious over the
combination of Ho, Davies, and Mizuhara. Ans. 14-15.

ISSUES
Did the Examiner err in finding claims 1-20 and 24 are indefinite for
failing to particularly point out and distinctly claim the subject matter which
Appellant regards as the invention?
Did the Examiner err in finding the combination of Ho and Mizuhara
teaches or suggests “delaying the second data stream with respect to the first
Appeal 2011-005701
Application 11/614,325

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data stream by a delay time greater than a bit-period duration,” as recited in
claim 1?
1

Did the Examiner err in finding the combination of Ho and Davies
teaches or suggests “a nested optical Mach-Zehnder modulator (MZM),” as
recited in claim 21?
2

ANALYSIS
35 U.S.C. § 112, Second Paragraph Rejection
The Examiner rejects claims 1-20 and 24 under 35 U.S.C. § 112,
second paragraph. Final Rej. 2; Ans. 4. Claim 1 recites “misaligning a data
stream with respect to a first data stream by one half of a bit period” and
then also recites “the step of misaligning comprises delaying the second data
stream with respect to the first data stream by a delay time greater than a bit-
period duration.” Independent claims 9 and 20 and dependent claim 24
contain similar limitations. Claims 2-8 and 10-19 are dependent upon
claims 1 and 9.
The Examiner finds that the scope of the claims is not clear since the
claimed misaligning is by both a period of a half bit and more than one bit.
Final Rej. 2; Ans. 16. Appellant argues that the claims are not indefinite.
App. Br. 6; Reply Br. 2. Appellant contends that the Specification makes it
clear that the term “alignment” means that the transition edges occur at
substantially the same time. App. Br. 6. Therefore, misalignment would

1
Appellant makes additional arguments with respect to claims 1-20. App.
Br. 7-10; Reply Br. 3. We will not address the additional arguments as
resolution of this issue is dispositive of the Appeal regarding these claims.
2
Appellant makes additional arguments with respect to claims 21-24. App.
Br. 10-12; Reply Br. 4-5. We will not address the additional arguments as
resolution of this issue is dispositive of the Appeal regarding these claims.
Appeal 2011-005701
Application 11/614,325

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mean that the transition edges do not occur at substantially the same time
and misaligning by a half bit period would mean that the transition edges
occur a half bit period apart. As such, Appellant contends that the delaying
step, included as an additional step within the misaligning step, requiring a
delay of greater than a bit-period, is not indefinite. Rather, the misaligning
step restricts possible time shifts to include only time shifts that are equal to
or greater than a 1 ½ bit period. Reply Br. 2. That is, the claim’s inclusion
of the misaligning step excludes delays that are only one half of a period.
We agree with Appellant. Appellant’s Specification reasonably
supports a finding that the term “misaligning” requires the transition edges
of the two data streams to be shifted from each other by a half-bit period and
delayed from each other by more than a bit period. Thus, we cannot sustain
the Examiner’s rejection of claims 1-20 and 24 under 35 U.S.C. § 112,
second paragraph.

Claims 1-20
Independent claim 1 recites “delaying the second data stream with
respect to the first data stream by a delay time greater than a bit-period
duration.” Independent claims 9 and 20 recite similar limitations. Claims 2-
8 and 10-19 depend from independent claims 9 and 20, respectively.
The Examiner finds that Ho discloses a method of generating an optical
duobinary signal the includes every limitation of independent claim 1 except
for misaligning by delaying the second data stream with respect to the first
data stream by a delay time greater than a bit-period corresponding to the
first rate. Ans. 5. The Examiner further finds that Mizuhara teaches
delaying the signals on one modulator arm of a duobinary transmitter
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relative to another arm by 180 degrees and, therefore, one of ordinary skill in
the art could have used any 180 degree delay period. Ans. 5-6.
Appellant argues that the claim specifically calls for a delay of greater
than one bit period and that there is nothing in the references or in the
Examiner’s Final Rejection that explains why a teaching of a 180 degree
delay in Mizuhara would have made obvious a delay of greater than one bit
period. App. Br. 7. Appellant makes additional arguments as to why it
would not have been obvious to combine Mizuhara with Ho. App. Br. 7-10;
Reply Br. 3. In response, the Examiner mainly focuses on Appellant’s
additional arguments and addresses Appellant’s initial argument by finding
that the concept taught by the reference is a “relative delay between two
streams specified in degrees.” Ans. 17.
We disagree with the Examiner’s findings and reasoning. The portion
of Mizuhara cited by the Examiner does not disclose a “relative” delay, but
rather that the phase-shift is “180 degrees relative to the clock signal.” See
Mizuhara, col. 4, ll. 26-27. Thus, the Examiner has not provided sufficient
evidence that either Ho or Mizuhara explains why one of ordinary skill in
the art would have used anything more than a 180 degree delay, as taught by
Mizuhara. As such, we cannot sustain the Examiner’s rejection of claims 1-
20.

Claims 21-24
Independent claim 21 recites “a nested optical Mach-Zehnder
modulator (MZM.)” Claims 22-24 depend from claim 21. The Examiner
finds that using the MZM arrangement in Davies for the modulation
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described in Ho creates a nested MZM, as required by the claims. Ans. 13-
14 and 19. We disagree.
Appellant describes a “nested MZM” as a configuration in which an
upper arm, comprising a data signal and its inverse, incorporates one MZM
and a lower arm, also comprising a data signal and its inverse, incorporates
another MZM. See Spec. 8:1-6. Appellant argues that neither of these
references, either alone or in combination, teaches a nested MZM or the
ability to create a nested configuration. App. Br. 11; Reply Br. 5.
We agree with Appellant. In fact, neither of the cited references even
teaches the use of multiple MZMs, much less nested MZMs. Therefore, the
rejection does not provide a sufficient explanation as to how Davies is
combined with Ho in order to create the claimed nested MZM or why one of
ordinary skill in the art would have combined multiple MZMs with Ho. As
such, we cannot sustain the Examiner’s rejection of claims 21-24.

CONCLUSION
The Examiner erred in finding claims 1-20 and 24 are indefinite for
failing to particularly point out and distinctly claim the subject matter which
Appellant regards as the invention.
The Examiner erred in finding the combination of Ho and Mizuhara
teaches or suggests “delaying the second data stream with respect to the first
data stream by a delay time greater than a bit-period duration,” as recited in
claim 1.
The Examiner erred in finding the combination of Ho and Davies
teaches or suggests “a nested optical Mach-Zehnder modulator (MZM),” as
recited in claim 21.
Appeal 2011-005701
Application 11/614,325

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SUMMARY
The Examiner’s decision to reject claims 1-20 and 24 under 35 U.S.C.
§ 112, second paragraph, is reversed.
The Examiner’s decision to reject claims 1-24 under 35 U.S.C.
§ 103(a) is reversed.
REVERSED

ELD