Ex Parte Pischl

Patent Trial and Appeal Board

Nov 19, 2013

11563349 (P.T.A.B. Nov. 19, 2013)

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.
11/563,349 11/27/2006 Neven Pischl 14528.00278 1792
16378 7590 11/19/2013
BGL/Broadcom
P.O. Box 10395
Chicago, IL 60610
EXAMINER
BALDRIDGE, BENJAMIN M
ART UNIT PAPER NUMBER
2866
MAIL DATE DELIVERY MODE
11/19/2013 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 NEVEN PISCHL
________________

Appeal 2011-005363
Application 11/563,349
Technology Center 2800
________________

Before DEBORAH KATZ, JOHN G. NEW, and HUNG H. BUI,
Administrative Patent Judges.

NEW, Administrative Patent Judge.

DECISION ON APPEAL

Appeal 2011-005363
Application 11/563,349

2
SUMMARY
Appellant files this appeal under 35 U.S.C. § 134(a) from the
Examiner’s Final Rejection of claims 1-27. Specifically, claims 1, 2, 19,
and 20 stand rejected as unpatentable under 35 U.S.C. § 103(a) as being
obvious over the combination of Oliver et al. (US 4,766,386, August 23,
1988) (“Oliver”) and Blades et al. (US 2005/0212526 A1, September 29,
2005) (“Blades”).
Claims 3, 7, 9, 21, 25, and 27 stand rejected as unpatentable under 35
U.S.C. § 103(a) as being obvious over the combination of Oliver, Blades,
and Bryant (US 7,230,970 B1, June 12, 2007) (“Bryant”).
Claims 4-6, 8, 22-24, and 26 stand rejected as unpatentable under 35
U.S.C. § 103(a) as being obvious over the combination of Oliver, Blades,
and Karam (US 2006/0117089 A1, June 1, 2006) (“Karam”).
Claims 10 and 11 stand rejected as unpatentable under 35 U.S.C.
§ 103(a) as being obvious over the combination of Oliver, Blades, and Lo et
al. (US 2006/0182269 A1, August 17, 2006) (“Lo”).
Claims 12, 16, and 18 stand rejected as unpatentable under 35 U.S.C.
§ 103(a) as being obvious over the combination of Oliver, Blades, Lo and
Bryant.
Claims 13-15 and 17 stand rejected as unpatentable under 35 U.S.C.
§ 103(a) as being obvious over the combination of Oliver, Blades, Lo and
Karam.
We have jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM.

Appeal 2011-005363
Application 11/563,349

3
NATURE OF THE CLAIMED INVENTION
Appellant’s invention is directed to a method and system for
detecting transformer saturation in a communication interface. The method
may include detecting a change in impedance resulting from transformer
saturation of at least one isolation transformer utilized in a network path of
a network. The network may conform to an IEEE 802.3af specification
where power can be delivered through the network. The method may
further comprise generating a pulse at a one end of the network and
measuring a reflection at that end to detect the transformer saturation. In
response to the impedance change, a transmitter signal may be pre-distorted
in order to compensate for the detected transformer saturation, or the power
delivered over the network may be disabled. Abstract.

GROUPING OF CLAIMS

Because Appellant makes substantially the same arguments with
respect to claims 1-3, 7, 9-12, 16-21, 25, and 27, we select claim 1 as
representative of these claims. App. Br. 10, 28, 30. Claim 1 recites:
1. A method for processing signals in a communication
system, the method comprising: detecting a change in
impedance resulting from transformer saturation of at least one
transformer utilized in a network path of a network.

App. Br. 35.
Appellant makes the same additional arguments with respect to
dependent claims 4-6, 8, 13-15, 17, 22-24, and 26. App. Br. 28. We
accordingly group these claims together and select claim 4 as
representative. Claim 4 recites:
Appeal 2011-005363
Application 11/563,349

4
4. The method according to claim 1, comprising delivering
power through said network path via said at least one
transformer.

App. Br. 35.

ISSUES AND ANALYSES
A. Claim 1
Issue
Appellant argues that the Examiner erred in finding that the
combination of Oliver and Blades teaches or suggests the limitation of
claim 1 reciting “detecting a change in impedance resulting from
transformer saturation of at least one transformer utilized in a network path
of a network.” App. Br. 11. We therefore address the issue of whether the
Examiner so erred.

Analysis
Appellant makes numerous repetitive arguments with respect to
claim 1, which we combine here. Appellant argues that Oliver teaches the
use of Time Domain Reflectometry (“TDR”) only to detect and locate
discontinuities (the alleged “change in impedance”) resulting from an open
or a short circuit, which is unrelated to a transformer, or to “transformer
saturation.” App. Br. 12. According to Appellant, Oliver cannot explicitly
disclose using TDR for “detecting a change in impedance resulting from
transformer saturation of at least one transformer” as required by claim 1,
Appeal 2011-005363
Application 11/563,349

5
because it does not mention the work “transformer” or “transformer
saturation.”
1
Id.
Appellant contends that not only does Oliver not disclose or suggest
the limitation of claim 1 reciting “resulting from transformer saturation of a
transformer utilized in a network path of a network,” Oliver also does not
disclose or suggest the alleged “transformer saturation causes impedance
discontinuities,” or “detecting a change in impedance resulting from
transformer saturation of a transformer utilized in a network path of a
network” and that, therefore, Oliver neither teaches nor suggests the
disputed limitation of claim 1. App. Br. 15.
Appellant also argues that the transformer taught by Blades is solely
for impedance matching, and that Blades does not disclose or suggest

1
Appellant also argues that the Examiner improperly introduced references
Editors of Conformity, EMC Components; Understanding Transformers:
Characteristics and Limitations, CONFORMITY, 1 (2007) and Paul
Matthews, Unwinding Distribution Transformers, 159 RANENOTE 1 (2004),
as the basis for a new ground of rejection. App. Br. 13. (citing MPEP §
706.07(a)). The Examiner explains that the references were not introduced
as the basis for a new ground of rejection, but rather that the Examiner’s
intent in furnishing these additional references was to make clear that
electrically and physically speaking, an impedance discontinuity due to
transformer saturation was known to be no different from any other
impedance discontinuity and that instrumentation in widespread use to
detect and measure such discontinuities (such as the Agilent 8510 series
vector network analyzers) was well known to persons of ordinary skill in
the art at the time of the invention. Ans. 15. Since the Examiner does not
rely upon these references to support the grounds of rejection for claim 1,
we take no notice of them in the instant appeal and rely solely upon those
prior art references cited by the Examiner in the Final Rejection of the
claims on appeal. See SUMMARY, supra.
Appeal 2011-005363
Application 11/563,349

6
“impedance change due to transformer saturation” or “detecting an
impedance change resulting from transformer saturation” as recited in claim
1. App. Br 16. According to Appellant, Blades discloses measuring the
source resistance, which includes the impedance of the distribution
transformer, then determining the load center wire resistance by subtracting
the source resistance from the measured resistance of the adapter plug to the
load center. App. Br. 17. Moreover, contends Appellant, Blades never
recites the claim terms “transformer saturation” or “an impedance
discontinuity resulting from transformer saturation.” Id.
Finally, Appellant argues that the Examiner has misconstrued
Appellant’s claim as reciting a structural difference of the element, instead
of the functions performed by the element. Ans. 24. Appellant argues that
claim 1 recites detecting functions or steps performed by a communication
system; and that claim 19 recites a circuit that enables such detecting
functions. Id.
The Examiner responds that Oliver teaches or suggests all of the
limitations of claim 1, except the disputed limitation “detecting a change in
impedance resulting from transformer saturation of at least one transformer
utilized in a network path of a network.” Ans. 16. However, the Examiner
finds that Blades cures this deficiency. Id. The Examiner finds that Blades
explicitly teaches measurement of transmission line impedance including a
distribution transformer and use of TDR to measure impedances on wiring.
Id. (citing Blades, [0094], [0133], [0201]). The Examiner also finds that the
motivation for a person of ordinary skill in the art to combine Oliver with
Blades is suggested by Oliver’s explicit disclosure of the use of TDR to
Appeal 2011-005363
Application 11/563,349

7
detect impedance discontinuities of any kind. Ans. 16 (citing Oliver, col. 1,
ll. 10-16; 30-35).
The Examiner finds that, regardless of whether an impedance
discontinuity results from transformer saturation, cable imperfections,
component impedance mismatches or failures, the impedance mismatch
will be detected by TDR. Ans. 18. Furthermore, finds the Examiner, the
use of TDR to detect impedance discontinuities of any kind is well known
in the electrical test and measurement arts. Id.
In summary, the Examiner finds that that an impedance discontinuity
due to transformer saturation is no different in kind, physically or
electrically speaking, than any other impedance discontinuity, as is well
understood by persons of skill in the art, and that the TDR apparatus and
method disclosed by Oliver and Blades will detect any impedance
discontinuity, no matter what the cause. Ans. 19. Consequently, the
Examiner concludes, it would have been obvious to an artisan of ordinary
skill to combine the teachings of Oliver and Blades to arrive at the
invention of claim 1.
Finally, the Examiner finds that the methods disclosed in the claims
are also intrinsic to the apparatus disclosed in the claims, since the method
steps will be met during the normal operation of the apparatus. Ans. 22.
We are persuaded by the Examiner’s findings of fact and reasoning
and adopt it as our own. Oliver explicitly teaches that:
Time domain reflectometry (TDR) is a well-known
method for determining the general characteristics of
impedance variations in a transmission line. In this method a
test pulse or step waveform is transmitted down the line and
the reflection from an impedance discontinuity is detected
Appeal 2011-005363
Application 11/563,349

8
together with the time it takes for the pulse to reach the
discontinuity and return.

Oliver, col. 1, ll. 21-27. Furthermore, Blades explicitly teaches that “[t]he
wire resistance measured above includes the impedance of the distribution
transformer and the service feed line to the house” and that “[i]t is a
relatively simple matter to measure the length of an isolated section of
Romex cable using conventional step time-domain reflectometry (TDR)
techniques with good results.” Blades, ¶¶ [0094]; [0201]. We consequently
agree with the Examiner that Blades thus teaches the measurement of
impedance and detection of impedance mismatches in a network
transformer, regardless of whether such an impedance is caused by
saturation. We also find that Appellant has failed to demonstrate that an
impedance discontinuity due to transformer saturation is somehow different
in kind from an impedance discontinuity due to other causes. Ans. 23. We
therefore affirm the Examiner’s rejection of claim 1.

B. Claim 4
Issue
Appellant argues that, in addition to the reasons argued with respect
to claim 1, the Examiner erred in finding that the cited prior art references
teach or suggest the limitation of claim 4 reciting “delivering power through
said network path via said at least one transformer.” App. Br. 28. We
therefore address the issue of whether the Examiner so erred.

Appeal 2011-005363
Application 11/563,349

9
Analysis
Appellant argues that, although Karam discloses using isolation
transformers T1 and T2 in the transmitter and the receiver, respectively,
Karam does not teach or suggest that there is any saturation issue in the
isolation transformers T1 and T2, let alone detecting the alleged impedance
change resulting from saturation of the isolation transformers. App. Br. 28
(citing Karam, Fig. 2). Appellant also argues that Karam does not disclose
or suggest “disabling the delivered power in response to the detecting [of
isolation transformer saturation],” as recited in Appellant's related
dependent claims 5 and 23.
The Examiner responds that, as related supra, the combination of
Oliver, Blades and Karam teaches or suggests the detection of impedance
discontinuities using TDR, and that the physical nature of the claimed
impedance change due to transformer saturation is no different than any
other impedance change or discontinuity. Ans. 25. The Examiner further
finds that, with respect to Appellant’s argument with respect to claims 5 and
23, Oliver teaches that “[b]y providing such a biasing capability in the time
domain reflectometer, all transceivers can be disabled from the TDR test
site rather than having to resort to individual shut down operations at each
interface site. Id. (citing Oliver, col. 6, l. 42-51).
We are persuaded by the Examiner’s fact finding and reasoning.
Oliver explicitly teaches that:
By biasing the Ethernet transmission line cable below
the collision detection threshold, it is possible to disable all
transceivers. By providing such a biasing capability in the
time domain reflectometer, all transceivers can be disabled
from the TDR test site rather than having to resort to individual
shut down operations at each interface site.
Appeal 2011-005363
Application 11/563,349

10

Oliver, col. 6, ll. 39-46. We agree with the Examiner that the teaching of
Oliver thus reads directly on the disputed limitation of claims 5 and 23 and
we affirm the Examiner’s rejection of the claims.

DECISION
The Examiner’s rejection of claims 1-27 under 35 U.S.C. § 103(a) is
affirmed.

TIME PERIOD FOR RESPONSE
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). See 37 C.F.R.
§ 1.136(a)(1)(iv).

AFFIRMED

kis