MAXLINEAR ASIA SINGAPORE PRIVATE LIMITED

Patent Trials and Appeals Board

Jul 28, 2021

2020002357 (P.T.A.B. Jul. 28, 2021)

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.
13/932,177 07/01/2013 Yaacov Sturkovich M3921.10019US02 9601
164869 7590 07/28/2021
MB - MAXLINEAR, INC.
1389 Center Drive, Suite 300
Park City, UT 84098
EXAMINER
TSVEY, GENNADIY
ART UNIT PAPER NUMBER
2648
NOTIFICATION DATE DELIVERY MODE
07/28/2021 ELECTRONIC
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.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
d@mabr.com
PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE

BEFORE THE PATENT TRIAL AND APPEAL BOARD

Ex parte YAACOV STURKOVICH

Appeal 2020-002357
Application 13/932,177
Technology Center 2600

Before ROBERT E. NAPPI, JOHNNY A. KUMAR, and
MICHAEL T. CYGAN, Administrative Patent Judges.

CYGAN, Administrative Patent Judge.

DECISION ON APPEAL
STATEMENT OF THE CASE
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims 1–7, 10–12, and 14–21. Appeal Br. 6,
15. Claims 8, 9, and 13 have been cancelled. Appeal Br. 17–18 (Claims
App.). We have jurisdiction under 35 U.S.C. § 6(b).
We REVERSE.

1 We use the word “Appellant” to refer to “applicant” as defined in
37 C.F.R. § 1.42. Appellant identifies the real party in interest as MaxLinear
Asia Singapore Pte Ltd. Appeal Br. 1.
Appeal 2020-002357
Application 13/932,177

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CLAIMED SUBJECT MATTER
The claimed subject matter generally relates to communication
interference reduction in point-to-point communication. Spec. 1:18–21.
Microwave technology is frequently used for point-to-point communications
because microwaves are more easily focused into narrow beams than radio
waves, and additionally have comparatively higher frequencies leading to
broad bandwidth, high data flow, and require smaller antennas. Id. at 2:1–5.
The characteristics of the microwave signals are measured by a spectrum
analyzer, which is a diagnostic tool for measuring the characteristics of a
signal. Id. at 4:1–9.
Independent claim 1 is illustrative:
1. A point-to-point communications unit, comprising:
a microwave transmitter operable to generate outgoing
microwave communication signals in a selected operational
bandwidth;
a microwave receiver comprising a first receiver path and a
second receiver path, wherein the first receiver path and the
second receiver path each comprise two channels, the first
receiver path comprising a wide band low-pass filter configured
to capture incoming microwave communication signals and
distortion in adjacent frequencies, the second receiver path
comprising a two-channel analog low-pass filter;
a microwave antenna operable to transmit outgoing microwave
communication signals and operable to receive incoming
microwave communication signals as line of sight
communication signals; and
a digital spectrum analyzer configured to determine distortion,
wherein the distortion is generated by out-of-band interferers
associated with incoming microwave communication signals,
and wherein the distortion is generated by non-linearities in a
Appeal 2020-002357
Application 13/932,177

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transmit path while maintaining the incoming line of sight
communications signals, and wherein the out-of-band
interferers are determined according to the captured incoming
microwave communication signals in the second receiver path
and incoming microwave communication signals in the first
receiver path that bypass a two-channel analog band low-pass
filter.
Appeal Br. 16 (Claims App.). Independent claims 10 and 15 recite,
respectively, a method and a communications unit having limitations similar
to that of claim 1. Id. at 17–19. Dependent claims 2–7, 11, 12, 14, and 16–
21 each incorporate the limitations of their respective independent claims.
Id. at 16–20.
REFERENCES
Name Reference Date
Ben-Efraim US 5,630,212 May 13, 1997
Diener et al.
(“Diener”)
US 2011/0090939 A1 Apr. 21, 2011
Haub et al.
(“Haub”)
US 2013/0102267 A1 Apr. 25, 2013
Chari et al. US 2013/0156140 A1 June 20, 2013
Laporte US 2014/0139286 A1 May 22, 2014

REJECTIONS
Claims 1–4, 15–18, and 21 are rejected under 35 U.S.C. § 103 as
being obvious over the combination of Ben-Efraim, Haub, and Laporte
Claims 5–7, 19, and 20 are rejected under 35 U.S.C. § 103 as being
obvious over the combination of Ben-Efraim, Haub, Laporte, and Diener.
Claims 10–12 are rejected under 35 U.S.C. § 103 as being obvious
over the combination of Ben-Efraim, Chari, and Laporte.
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Application 13/932,177

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Claim 14 is rejected under 35 U.S.C. § 103 as being obvious over the
combination of Ben-Efraim, Chari, Laporte, and Diener.

OPINION
Appellant’s central contention of error in the Examiner’s rejection is
that none of the references, individually or in combination, teach or suggest
a “digital spectrum analyzer” as claimed. We are persuaded, as discussed
infra.
Claim 1 recites, inter alia:
a digital spectrum analyzer configured to determine distortion,
wherein the distortion is generated by out-of-band interferers
associated with incoming microwave communication signals,
and wherein the distortion is generated by non-linearities in a
transmit path while maintaining the incoming line of sight
communications signals, and wherein the out-of-band
interferers are determined according to the captured incoming
microwave communication signals in the second receiver path
and incoming microwave communication signals in the first
receiver path that bypass a two-channel analog band low-pass
filter
The Examiner finds such a digital spectrum analyzer to be missing in
Ben-Efraim. Final Act. 15. The Examiner finds Haub to teach a digital state
machine (254) that, together with power estimation circuits (Pdet1 220 and
Pdet2 230), forms a “spectrum analyzer” that “measures the power of a
signal in multiple frequency bands or determines frequency components
comprising the signal.” Id. at 16. The Examiner finds that this collection of
components in Haub performs analysis of the signal spectrum to determine if
any Out-of-Band signals may be present. Id. at 16–17. Thus, the Examiner
finds Haub to teach a digital spectrum analyzer configured to determine
“distortion generated by out-of-band interferers,” as set forth in claim 1.
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However, the Examiner does not find the limitation of the distortion
also being “generated by nonlinearities in a transmit path” to be taught by
the combination of Haub and Ben-Efraim. Id. at 18. For this limitation, the
Examiner relies upon additional teachings of Laporte.
The Examiner cites Laporte for illustrating a “conventional system 10
that implements a digital predistortion approach to determine and
compensate for non-linearities of a power amplifier 12. Id. The Examiner
characterizes this as “representing distortion ‘generated by nonlinearities in a
transmit path.” Id. The Examiner explains that the illustrated system
contains an “adaptor 28 that configures the coefficients of the predistorter 18
based on the comparison of the time-aligned as well as gain and phase
adjusted versions of the observation signal (So) and the reference signal
(SR) and thus determine[s] distortion ‘generated by non-linearities in a
transmit path.’” Id. The Examiner further comparing Laporte’s teachings to
the descriptions in Appellant’s specification, finding a correspondence
between Laporte’s adaptive digital pre-distortion correction and Appellant’s
disclosed adaptor that configures the coefficients of a predistorter based on
the comparison of the time-aligned as well as gain and phase-shifted version
of the observation and reference signals. Id. at 19–20. The Examiner,
further finds that the combined circuitry of Laporte and Haub would be
“functionally equivalent” to Appellant’s disclosed “digital spectrum
analyzer,” because the combined system “analyzes, measures, and or
determines, directly or indirectly, [the] presence of out of band distortion in
the received signal and non-linearities in the power amplifier.” Id. at 20.
In their obviousness analysis, the Examiner provides further findings
as to how certain claimed features are described in Appellant’s specification.
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For example, with respect to the distortions due to non-linearities of the
transmit path, the Examiner argues that such a function is not disclosed by
Appellant in connection with any spectrum analysis. Ans. 52–53. The
Examiner further finds that Appellant’s specification mentions fast Fourier
transforms, as a spectrum analyzer function, but not as part of compensation
of nonlinearities in the transmit path as claimed. Id. 54–55. The Examiner
concludes that if the Specification discloses a manner of performing a
compensation without spectrum analysis, and if Laporte describes the same
manner, then Laporte teaches the claimed compensation even though
Laporte does not teach the compensation being done with a spectrum
analyzer. Id. at 55–58.
Appellant argues that Laporte does not teach a digital spectrum
analyzer. Appeal Br. 8. Appellant further argues that Laporte’s adapter 28
is not an equivalent to the claimed spectrum analyzer. Id. at 9. Appellant
argues that a person having ordinary skill in the art reading the claimed
limitation in view of the Specification would understand that a digital
spectrum analyzer measures “spectral components of a signal,” for example,
by Fourier analysis or Fourier transformation. Id. (citing Spec. 4:2–4
(“spectrum analyzers are often used to measure . . . and other spectral
components of a signal”). Appellant points to portions of the Specification
consistent with that understanding of a spectrum analyzer. Id. at 10 (“unit
300 includes an integrated spectrum analyzer with digital signal processor
(DSP) 302” and explaining that the DSP processing signals through a digital
fast Fourier transform (citing Spec. 6:18–19; 7:17–19)). Appellant argues
that Laporte does not teach any spectral analysis, and therefore, does not
teach a spectrum analyzer. Id. at 10.
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We are persuaded by Appellant’s argument that the Examiner has
“failed to show that the Prior Art (in any combination) teaches “a digital
spectrum analyzer configured to determine distortion . . . wherein the
distortion is generated by non-linearities in a transmit path.” Reply Br. 6.
The Examiner does not point to any teaching of a spectrum analyzer in either
Laporte or Haub. Instead, the Examiner points to the combined circuitry for
processing and compensation of Laporte and Haub as teaching the claimed
digital spectrum analyzer. Ans. 50. However, the Examiner does not
explain how that combined circuitry results in something that would be
recognized by one skilled in the art as a “digital spectrum analyzer.” At
best, the Examiner finds that the circuitry of Laporte and Haub could be
combined to reach the same result desired by Appellant, determination and
compensation of distortion generated by out-of-band interferers and by
nonlinearities in a transmit path. Ans. 51–58. But the claim requires that the
result be reached by a specifically claimed device, a “digital spectrum
analyzer.” Thus, the applied combination of prior art must be shown to
teach or suggest a “digital spectrum analyzer.” See In re Robertson, 169
F.3d 743, 745, 49 USPQ2d 1949, 1951 (Fed. Cir. 1999) (finding that a claim
reciting three fastening elements is not met by prior art showing two
fastening elements that could perform the same function as the three
fastening elements).
The Examiner’s discussion of the description in the Specification does
not provide support for the Examiner’s obviousness finding. A showing of
obviousness here must explain how the prior art teaches or suggests circuitry
that a person having ordinary skill in the art would recognize, in light of the
Specification, as a digital spectrum analyzer configured to determine
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distortion generated by non-linearities in a transmit path. Instead, the
Examiner attempts to show that Appellant’s specification does not, in fact,
describe a digital spectrum analyzer performing compensation of distortion
generated by non-linearities in a transmit path. Ans. 51–52. That
discussion, while pertinent to a rejection based upon lack of written
description under 35 U.S.C. § 112,2 has no bearing on an obviousness
determination. An obviousness determination requires a showing that the
prior art teaches or suggests all claimed limitations, including limitations
that may not find support in the specification. Ex parte Grasselli, 231
USPQ 393 (Bd. App. 1983) aff’d mem. 738 F.2d 453 (Fed. Cir. 1984)
(Claim to a catalyst expressly excluded the presence of sulfur, halogen,
uranium, and a combination of vanadium and phosphorous. Although the
negative limitations excluding these elements did not appear in the
specification as filed, it was error to disregard these limitations when
determining whether the claimed invention would have been obvious in
view of the prior art).
Because the Examiner has not shown the applied prior art to teach or
suggest the claimed digital spectrum analyzer performing the claimed
functions, we are persuaded that the Examiner has not shown claim 1 to be
obvious.
For the same reason, the Examiner has not shown claims 2–4, 15–18,
and 21, which were rejected under the same grounds and the same

2 The Examiner does not set forth any rejection based upon written
description under 35 U.S.C. § 112(a), and we do not address any such issue
in this decision.
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Application 13/932,177

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obviousness rationale, to be obvious. Thus, we reverse the Examiner’s
rejection of claims 1–4, 15–18, and 21.
Claims 5–7, 19, and 20 are rejected under the same base combination
of Ben-Efraim, Haub, and Laporte, further in view of Diener. However, the
Examiner has not shown Diener to provide the digital spectrum analyzer
performing the claimed functions, as found lacking in the independent
claims from which these claims depend. Consequently, the Examiner has
not shown claims 5–7, 19, and 20 to be obvious over the applied prior art,
and we reverse the rejection of those claims.
Claims 10–12 are rejected under a combination of Ben-Efraim,
Laporte, and Chari. However, the Examiner states that the combined
teachings of Ben-Efraim and Laporte do not teach or suggest “using a digital
spectrum analyzer to determine the distortion generated by the non-
linearities in the transmit path,” relying instead on Laporte as explained in
the rejection of claim 1. Final Ans. 42. Thus, we reverse the rejections of
claims 10–12 for the same reasons as discussed for the rejection of claim 1.
Claim 14, rejected over Ben-Efraim, Laporte, and Chari further in view of
Diener, is reversed for the same reason.
CONCLUSION
For the above-described reasons, we reverse the Examiner’s
obviousness rejection of claims 1–7, 10–12, and 14–21 over the applied art,
as summarized below.

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Application 13/932,177

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DECISION SUMMARY
In summary:
Claims
Rejected
35 U.S.C. § References/Grounds Affirmed Reversed
1–4, 15–
18, 21
103 Ben-Efraim, Haub,
Laporte
1–4, 15–
18, 21
5–7, 19,
20
103 Ben-Efraim, Haub,
Laporte, Diener
5–7, 19,
20
10–12 103 Ben-Efraim, Chari,
Laporte
10–12
14 103 Ben-Efraim, Chari,
Laporte, Diener
14
Overall
Outcome
1–7, 10–
12, 14–
21

REVERSED