Ex Parte Snawerdt

Board of Patent Appeals and Interferences

Feb 19, 2010

09809936 (B.P.A.I. Feb. 19, 2010)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte PETER SNAWERDT
____________

Appeal 2009-002330
Application 09/809,936
Technology Center 2600
____________

Decided: February 22, 2010
____________

Before ROBERT E. NAPPI, CARLA M. KRIVAK, and
BRADLEY W. BAUMEISTER, Administrative Patent Judges.

KRIVAK, Administrative Patent Judge.

DECISION ON APPEAL
Appellant appeals under 35 U.S.C. § 134(a) from a final rejection of
claims 1-20. We have jurisdiction under 35 U.S.C. § 6(b).
We affirm.

Appeal 2009-002330
Application 09/809,936

2
STATEMENT OF THE CASE
Appellant’s claimed invention is a telecommunications apparatus and
method for transmitting and receiving secure data over a wave division
multiplexed fiber optic network (Spec. ¶¶ [0001], [0023], and [0025]). A
fiber optic transmitter includes first and second continuous wave lasers
producing light of different wavelengths that is phase-modulated by first and
second phase modulators, respectively (Spec. ¶¶ [0013], [0016]; Fig. 1).
The phase-modulated light is phase modulated as a function of first and
second data input streams and output as first and second output data streams.
A combiner then combines the first and second output data streams into
phase-modulated optical signals and transmits these signals over an optical
fiber as a function of first and second data input streams (Spec. ¶ [0013];
Fig. 1). A controller controls the phase modulators as a function of the
output from separate delayed-feedback exclusive-or gates receiving input
data streams (Spec. ¶ [0014]; Fig. 3). A receiver receives the combined
optical signals from the optical fiber and splits the optical signals back into
the first and second wavelengths and first and second interferometers detect
the first and second data streams, respectively (Spec. ¶¶ [0013], [0021], and
[0039]; Fig. 2). A detector detects a tap or loss of energy in the optical fiber
(Spec. ¶ [0018]).
Independent claim 1, reproduced below, is representative of the
subject matter on appeal.
1. A fiber optic data transmission system comprising:

an optical fiber; and

a data transmitter having a first laser having a first wavelength,
a first phase modulator for phase modulating light from the first
Appeal 2009-002330
Application 09/809,936

3
laser as a function of a first data input stream so as to create a
first phase-modulated output optical signal free of amplitude-
modulation as a function of the first data input stream, a second
laser having a second wavelength different from the first
wavelength, and a second phase modulator for phase
modulating light from the second laser as a function of a second
data input stream so as to create a second phase-modulated
output optical signal free of amplitude-modulation as a function
of the second data input stream, the transmitter further
including a combiner combining the first and second output
optical signals into a phase-modulated combined optical signal
for transmission over the optical fiber.

REFERENCES
Ono US 6,097,525 Aug. 1, 2000
(filed Aug. 15, 1997)
Davis US 6,215,565 B1 Apr. 10, 2001
(filed Jul. 27, 1998)
Hakki US 6,549,311 B1 Apr. 15, 2003
(filed Jul. 14, 1999)

The Examiner rejected claims 1, 4, 5, 7, 9, 10, 13, 14, 16-18, and 20
under 35 U.S.C. § 102(e) based upon the teachings of Hakki.
The Examiner rejected claims 2, 3, 8, and 15 under 35 U.S.C. § 103(a)
based upon the teachings of Hakki and Ono.
The Examiner rejected claims 6, 12, and 19 under 35 U.S.C. § 103(a)
based upon the teachings of Hakki and Davis.
The Examiner rejected claim 11 under 35 U.S.C. § 103(a) based upon
the teachings of Hakki.
Appellant contends Hakki’s phase-modulated telemetry signal is
superimposed over a high-speed data amplitude-modulated information
signal (App. Br. 5). Appellant further contends that Ono’s exclusive-or gate
has no applicability to Hakki’s RF signal generator of Hakki (App. Br. 6).
Appeal 2009-002330
Application 09/809,936

4
Appellant also contends that because Hakki is using telemetry signals and an
interferometer to monitor an optical fiber, one of ordinary skill in the art
would have viewed adding the device of Davis to monitor energy loss as
superfluous (App. Br. 7).

ISSUES
Did the Examiner err in finding Hakki’s phase-modulated telemetry
signal is free of amplitude-modulation as a function of a data input stream?1
Did the Examiner err in finding Hakki’s phase modulator could be
controlled as a function of a delayed-feedback exclusive-or gate taught by
Ono?
Did the Examiner err in finding Hakki’s optical fiber could be
monitored to detect a loss of energy as taught by Davis?

FINDINGS OF FACT
1. Hakki teaches a wave division multiplexing system that solves
inter-channel cross-talk problems associated with intensity-modulation by
phase-modulating telemetry signals (col. 1, ll. 39-44; col. 2, ll. 59-61; Fig.
1). Optical transmitter 110a includes a laser source 135a, operating at some
wavelength λ, outputting an optical signal (col. 2, ll. 53-56; Fig. 1). A low

1 The feature “free of amplitude-modulation” was added to the claims by the
Amendment filed December 9, 2002. In response to a 112, first paragraph
rejection (see Final Office Action mailed June 6, 2003), Appellant asserted
that support for this limitation is found in amended claim 1 of US Patent
6,594,055 having Application Serial Number 09/765,153, which is
incorporated by reference into the application on appeal (see Amendment
After Final filed September 8, 2003).

Appeal 2009-002330
Application 09/809,936

5
frequency telemetry signal is applied to an RF signal generator 140. Phase
modulator 145 modulates the optical signal with the RF signal (col. 2. ll. 59-
61; col. 4, ll. 24-29; Figs. 1 and 3).
2. Hakki also teaches the frequency of modulation and the phase
shift amplitude of the optical signal “are preferably selected to avoid phase
modulation/amplitude modulation (PM/AM) conversion in a dispersive
fiber” (col. 2, ll. 61-64).
3. Ono teaches an optical transmitter used with an optical fiber
(col. 6, ll. 63-65; col. 7, ll. 36-39; Fig. 8). A phase modulation signal is
inverted when an intensity modulation signal is zero by inverting an output
of an exclusive-or gate and a 1-bit delay circuit (col. 4, ll. 46-51; Figs. 8 and
9).
4. Davis teaches an optical performance monitor 37 (col. 3, ll. 44-
46; Fig. 1) for monitoring performance of an optical communications system
by measuring two different signal-to-noise ratios and a bit error rate on an
optical fiber span 19d (col. 2, ll. 10-18; col. 3, ll. 46-48; Fig. 1).

PRINCIPLES OF LAW
“A claim is anticipated only if each and every element as set forth in
the claim is found, either expressly or inherently described, in a single prior
art reference.” Verdegaal Bros., Inc. v. Union Oil Co. of California, 814
F.2d 628, 631 (Fed. Cir. 1987).
In rejecting claims under 35 U.S.C. § 103, it is incumbent upon the
Examiner to establish a factual basis to support the legal conclusion of
obviousness. See In re Fine, 837 F.2d 1071, 1073 (Fed. Cir. 1988).
Appeal 2009-002330
Application 09/809,936

6
Appellant has the burden on appeal to the Board to demonstrate error in the
Examiner’s position. See In re Kahn, 441 F.3d 977, 985-86 (Fed. Cir.
2006).

ANALYSIS
Anticipation
The Examiner rejected claims 1, 4, 5, 7, 9, 10, 13, 14, 16-18, and 20
under 35 U.S.C. § 102(e) as anticipated by Hakki (Ans. 3). Appellant argues
these claims together. This rejection is addressed with respect to claim 1.
Appellant does not contest that Hakki teaches a phase modulator.
(App. Br. 4; Reply Br. 2). Rather, Appellant contends, the output of Hakki’s
optical signal from the optical transmitter is a combined amplitude
modulated high-speed data signal and phase-modulated optical signal. The
amplitude-modulated signal is sent over a high-speed data signal as a
function of the phase-modulated telemetry signal and changes as a function
of a telemetry analysis (App. Br. 5; Reply Br. 2; FF 1).
It is clear that Hakki phase-modulates telemetry signals with phase
modulators; however, the modulation method for its high-speed data is not
expressly defined (FF 1). Even assuming the high-speed data signal of
Hakki is not phase-modulated, there is no evidence the signal would
necessarily be amplitude-modulated as Hakki seeks to avoid the negative
drawbacks associated with amplitude modulation (Ans. 9-10; FF 2).
Appellant has provided no persuasive evidence and has not identified a
specific citation in Hakki’s disclosure that teaches the high-speed data signal
is amplitude modulated. Thus, Appellant’s contention that one of ordinary
skill in the art would chose amplitude modulation for the high-speed data
Appeal 2009-002330
Application 09/809,936

7
signal in Hakki is unsupported. (Reply Br. 3). Accordingly, since Appellant
has not shown the Examiner erred in finding Hakki teaches phase-modulated
output optical signals free of amplitude-modulation as a function of a data
input stream, Hakki anticipates claims 1, 4, 5, 7, 9, 10, 13, 14, 16-18, and 20.

Obviousness
Claims 2, 3, 8, and 15
The Examiner rejected claims 2, 3, 8, and 15 under 35 U.S.C. § 103(a)
over Hakki and Ono (Ans. 7). The Examiner finds Hakki fails to teach
controlling the first phase modulator as a function of an output of a delayed-
feedback exclusive-or gate having a first input data stream as an input (Ans.
7). The Examiner then finds Ono teaches it was known in the art for a
controller to control a phase modulator as a function of an output of a
delayed-feedback exclusive-or gate (Ans. 13; FF 3). Appellant, however,
contends Ono’s exclusive-or gate has no applicability to Hakki’s RF signal
generator because Hakki functions without a feedback gate (App. Br. 6).
These claims are not rejected based on applying Ono’s exclusive-or
gate to Hakki’s RF signal generator. Rather, the Examiner cited Ono as
showing it was well known in the art at the time of Appellant’s invention to
control a phase modulator as a function of a delayed feedback exclusive-or
gate. (Ans.13) Thus, Appellant has not shown the Examiner erred in
rejecting claims 2, 3, 8, and 15 over Hakki and Ono.
Claims 6, 12, and 19
The Examiner rejected claims 6, 12, and 19 under 35 U.S.C. § 103(a)
over Hakki and Davis (Ans. 8). The Examiner finds Hakki fails to teach a
detector for detecting a tap or loss of energy in an optical fiber; however,
Appeal 2009-002330
Application 09/809,936

8
Davis shows one skilled in the art would have known to use a monitor for
monitoring system performance including a tap or loss of energy in an
optical fiber (Ans. 8; FF 4).
Appellant contends that because Hakki is using telemetry signals and
an interferometer to monitor the optical fiber “already (although not for
intrusion),” one of skill in the art would not have provided an additional
detector (App. Br. 7).
However, Hakki’s monitoring of the optical fiber using telemetry
signals and an interferometer does not preclude additionally monitoring the
optical fiber for a loss of energy as taught by Davis (Ans. 8, 13). Thus,
Appellant has not shown the Examiner erred in rejecting claims 6, 12, and
19 over Hakki and Davis.
Claim 11
The Examiner rejected claim 11 under 35 U.S.C. § 103(a) based upon
the teachings of Hakki (Ans. 8). Appellant asserts the same arguments for
claim 11 as claim 1 (App. Br. 6). Thus, for the reasons set forth above,
Appellant has not shown the Examiner erred in rejecting claim 11 over
Hakki.

CONCLUSION
The Examiner did not err in finding Hakki’s phase-modulated
telemetry signal is free of amplitude-modulation as a function of a data input
stream.
The Examiner did not err in finding Hakki’s phase modulator could be
controlled as a function of a delayed-feedback exclusive-or gate.
Appeal 2009-002330
Application 09/809,936

9
The Examiner did not err in finding Hakki’s optical fiber could be
monitored to detect a loss of energy as taught by Davis.
DECISION
The Examiner’s rejection of claims 1, 4, 5, 7, 9, 10, 13, 14, 16-18, and
20 under 35 U.S.C. § 102(e) is affirmed.
The Examiner’s rejection of claims 2, 3, 6, 8, 11, 12, 15, and 19 under
35 U.S.C. § 103(a) 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

KIS

Davidson, Davidson & Kappel, L.L.C.
485 7th Avenue
14th Floor
New York, NY 10018