Ex Parte King et al

Board of Patent Appeals and Interferences

Feb 23, 2007

10452753 (B.P.A.I. Feb. 23, 2007)

The opinion in support of the decision being entered today was not written
for publication in and is not binding precedent of the Board.

UNITED STATES PATENT AND TRADEMARK OFFICE
___________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
___________

Ex parte THOMAS M. KING, THOMAS RICKS, and DAVID MURRAY
___________

Appeal 2006-1385
Application 10/452,753
Technology Center 3600
___________

Decided: February 23, 2007
___________

Before STUART S. LEVY, ROBERT E. NAPPI, and LINDA E. HORNER
Administrative Patent Judges.
STUART S. LEVY, Administrative Patent Judge.

DECISION ON APPEAL

This appeal pursuant to 35 U.S.C. § 134 involves claims 1-19 and 23-26, the
only claims pending in this application. We have jurisdiction over the appeal 35
U.S.C. § 6(b).

We AFFIRM-IN-PART.

Appeal Number: 2006-1385
Application Number: 10/452,753

BACKGROUND

The Appellants’ invention relates to the detection and reduction of periodic
jamming signals in GPS receivers (Specification 1). An understanding of the
invention can be derived from a reading of exemplary claim 1, which is reproduced
below.
1. A method in a satellite positioning system receiver, the method
comprising:
detecting the presence of a jamming signal in the satellite positioning
system receiver after the jamming signal enters the satellite positioning
system receiver;
the jamming signal having a known pattern;
reducing the jamming signal by blanking the satellite positioning
system receiver with a blanking signal having a pattern similar to the
jamming signal synchronized with the jamming signal.

PRIOR ART
The prior art references of record relied upon by the examiner in rejecting the
appealed claims are:
Shridhara 6,448,925 Sep. 10, 2002
Fielder 6,681,181 Jan. 20, 2004
(May 20, 2002)
Beesley 2,113,047 A Jul. 27, 1983
(Great Britain)
REJECTIONS
Claims 1-19 and 23-26 stand rejected under 35 U.S.C. § 103(a) as being
unpatentable over Shridhara in view of Beesley.
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Claims 1-19 and 23-26 stand rejected under 35 U.S.C. § 103(a) as being
unpatentable over Shridhara in view of Fielder.
Rather than reiterate the conflicting viewpoints advanced by the Examiner and
the Appellants regarding the above-noted rejections, we make reference to the
Examiner's Answer (mailed November 10, 2005) for the reasoning in support of
the rejection, and to Appellants’ brief (filed August 26, 2005) and reply brief (filed
January 10, 2006) for the arguments thereagainst.
Only those arguments actually made by Appellants have been considered in
this decision. Arguments which Appellants could have made but chose not to
make in the brief have not been considered. See 37 C.F.R. § 41.37(c)(1)(vii)(eff.
Sept. 13, 2004).

OPINION
In reaching our decision in this appeal, we have given careful consideration to
the Appellants’ specification and claims, to the applied prior art references, and to
the respective positions articulated by the Appellants and the Examiner. As a
consequence of our review, we make the determinations that follow.
We begin with the rejection of claims 1-19 and 23-26 under 35 U.S.C. § 103(a)
as being unpatentable over Shridhara in view of Beesley. We note as background
that 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, 5 USPQ2d 1596, 1598 (Fed. Cir. 1988). In so
doing, the Examiner is expected to make the factual determinations set forth in
Graham v. John Deere Co., 383 U.S. 1, 17, 148 USPQ 459, 467 (1966), and to
provide a reason why one having ordinary skill in the pertinent art would have
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been led to modify the prior art or to combine prior art references to arrive at the
claimed invention. Such reason must stem from some teaching, suggestion or
implication in the prior art as a whole or knowledge generally available to one
having ordinary skill in the art. Uniroyal, Inc. v. Rudkin-Wiley Corp., 837 F.2d
1044, 1051, 5 USPQ2d 1434, 1438 (Fed. Cir. 1988); Ashland Oil, Inc. v. Delta
Resins & Refractories, Inc., 776 F.2d 281, 293, 227 USPQ 657, 664 (Fed. Cir.
1985); ACS Hosp. Sys., Inc. v. Montefiore Hosp., 732 F.2d 1572, 1577, 221 USPQ
929, 933 (Fed. Cir. 1984). These showings by the Examiner are an essential part
of complying with the burden of presenting a prima facie case of obviousness.
Note In re Oetiker, 977 F.2d 1443, 1445, 24 USPQ2d 1443, 1444 (Fed. Cir. 1992).
If that burden is met, the burden then shifts to the applicant to overcome the prima
facie case with argument and/or evidence. Obviousness is then determined on the
basis of the evidence as a whole. See id.; In re Hedges, 783 F.2d 1038, 1039, 228
USPQ 685, 686 (Fed. Cir. 1986); In re Piasecki, 745 F.2d 1468, 1472, 223 USPQ
785, 788 (Fed. Cir. 1984); and In re Rinehart, 531 F.2d 1048, 1052, 189 USPQ
143, 147 (CCPA 1976).
Regarding claim 1, the Examiner's position (Answer 3-5) is that Shridhara does
not disclose a jamming signal having a known pattern and a blanking signal having
a pattern similar to the jamming signal and synchronized with the jamming signal.
To overcome this deficiency of Shridhara, the Examiner turns to Beesley for a
teaching of a jamming signal having a known pattern and reducing the jamming
signal with a blanking signal having a pattern similar to and synchronized with the
jamming signal (id.).

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Appellants assert (Br. 5) that neither Shridhara nor Beesley show a blanking
signal having a pattern similar to the jamming signal and synchronized with the
jamming signal. Appellants further argue (id.) that there is no reason to combine
Shridhara and Beesley. According to Appellants, “there is no need to generate a
variable amplitude/duration blanking signal as disclosed by Beesley, since
Shridhara teaches turning off the receiver or suppressing GPS readings or notifying
the user that the GPS position determination may be inaccurate in the presence of a
jamming signal” (id.). Additionally, Appellants assert that Beesley does not teach
a jamming signal having a known pattern due to the random nature of noise
generated by an ignition system (id.).
Accordingly, the issue before us is whether the combined teachings and
suggestions of Shridhara and Beesley would have taught or suggested to an artisan
a jamming signal having a known pattern and reducing the jamming signal with a
blanking signal having a pattern similar to the jamming signal and synchronized
with the jamming signal, as recited in claim 1.
From our review of the record, we find that Shridhara is directed to a method
for jamming detection and blanking for GPS receivers (col. 1, ll. 1-2). Shridhara
discloses detecting the presence of a jamming signal in the GPS receiver using any
one of several methods (Fig. 9). These methods include analyzing a rise in the
output from a correlator chain within the GPS unit (col. 4, ll. 34-36), determining if
clock drift is present without a corresponding increase in temperature (col. 4, ll.
46-48), detecting sudden changes in signal to noise ratio (col. 4, ll. 53-55), and
monitoring received signal strength to determine a sudden increase (col. 8, ll. 30-
31). Shridhara characterizes the jamming signal as noise that is generated from a
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variety of sources including vehicle ignition systems (col. 10, ll. 20-29). Shridhara
further explains that once the jamming signal is detected, one or more
“countermeasures” are applied to reduce the effects of the jamming signal
(col. 4, ll. 26-31). Although Shridhara’s countermeasures include disabling the
GPS receiver input/output, notifying the user of the jamming signal, or applying
alternative position determination methods (col. 4, ll. 58-67), we do not find any
suggestion for reducing the jamming signal with a blanking signal having a pattern
similar to and synchronized with the jamming signal.
Turning to Beesley, we find that the reference is directed to noise blanking in a
radio receiver (p. 1, ll. 1-6). Beesley discloses a blanking signal that controls a
blanking circuit—an attenuator—for reducing the effects of noise pulses due to a
vehicle’s ignition system (p. 1, ll. 7-10). Beesley explains that a pulse detector
detects the presence of a jamming (noise) signal in the received signal (p. 1, ll.
81-84). After detection, the pulse detector determines certain characteristics of the
jamming signal, including the amplitude (p. 2, ll. 51-53) and rate of arrival (p. 3, ll.
104-107). A blanking signal is then generated based on these characteristics (p. 1,
ll. 56-61). Beesley explains that the purpose of generating a blanking signal based
on the characteristics of the jamming signal is to produce an optimized blanking
signal that effectively reduces the jamming signal (page 2, lines 82-87).
From our review of Beesley, we agree with the Examiner that Beesley teaches
a blanking signal having a pattern similar to a jamming signal. The two signals are
similar because the amplitude of the blanking signal is adjusted depending upon
the amplitude of the detected jamming signal.
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We further find that Beesley teaches generating a blanking signal synchronized
with the jamming signal. Beesley explains that the blanking signal is generated in
response to the detected presence of the jamming (noise) signal (p. 2, ll. 22-26).
Beesley further explains that the duration and amplitude of the blanking signal is
dependent upon the amplitude and rate of arrival respectively, of the detected
jamming signal (p. 2, ll. 22-26 and p. 3, ll. 104-107). Thus, we agree with the
Examiner that Beesley discloses generating a blanking signal that is not only
similar to the jamming signal, but also synchronized with the jamming signal.
We are not persuaded by Appellants’ assertion (Br. 5) that there is no reason to
combine Shridhara and Beesley. Appellants argue that there is no need to generate
the blanking signal, as disclosed by Beesley, in Shridhara because Shridhara either
turns off the receiver, suppresses GPS readings, or notifies the user (id.).
However, Shridhara does not limit the type of countermeasures to the ones
described by Appellants. Instead, Shridhara explains that “various jamming
countermeasures may be applied depending on the application in which the GPS
receiver is embedded” (col. 12, l. 66 to col. 13, l. 1).
From this disclosure of Shridhara, we find a suggestion of applying alternative
jamming countermeasures. As noted by the Examiner (Answer 5), Beesley teaches
a known alternative jamming countermeasure for reducing the effects of a detected
jamming signal in a receiver. From our review of Shridhara and Beesley, we agree
with the Examiner that it would have been obvious for an artisan to substitute one
of the jamming countermeasures in Shridhara with the one taught by Beesley,
which includes generating a blanking signal similar to and synchronized with the
jamming signal, in order to suppress the adverse effects of the jamming signal.
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Nor are we persuaded by Appellants’ assertion (Br. 5) that “in Beesley, the
noise generated by the ignition system is random and thus does not have a ‘known
pattern’.” The fact that noise is random does not necessarily mean that the noise
does not have a known pattern for the following reasons. It depends on whether
the pattern of the random noise must be known beforehand—predetermined—or
can be known after the noise is detected. Here, claim 1 merely recites a “jamming
signal having a known pattern.” Claim 1 does not require however, that the
jamming signal have a known pattern that is predetermined. In Beesley, the
pattern of the jamming signal becomes known once it is detected by the pulse
detector and the amplitude and rate of arrival of the jamming signal are
determined. Therefore, we agree with the Examiner that Beesley discloses a
jamming signal having a known pattern.
From all of the above, we conclude that the combined teachings of Shridhara
and Beesley would have suggested to an artisan the invention of claim 1, and are
not convinced of any error on the part of the Examiner in rejecting claim 1 under
35 U.S.C. § 103(a) as being unpatentable over Shridhara in view of Beesley.
Accordingly, the rejection of claim 1 is sustained.
We turn next to claim 2. Appellants provide no specific arguments regarding
this claim, but generally argue that Shridhara and Beesley do not disclose
monitoring the satellite positioning receiver. From our review of the record, we
find that Shridhara discloses monitoring the satellite positioning receiver (column
4, lines 31-57). Therefore, we are in agreement with the Examiner, for the reasons
set forth in the answer, that the teachings of Shridhara would have suggested to an
artisan the invention set forth in claim 2.
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For the lack of any specific arguments by Appellants, and our agreement with
the Examiner’s position, we are not persuaded of any error in the part of the
examiner regarding the rejection of claim 2. Accordingly, the rejection of claim 2
under U.S.C. § 103(a) as being unpatentable over Shridhara in view of Beesley is
sustained.
We turn next to claim 3. Appellants provide no specific arguments regarding
this claim, but generally argue that Shridhara and Beesley do not disclose
monitoring a signal correlator of the satellite positioning system receiver. From
our review of the record, we find the disclosure in Shridhara (col. 4, ll. 34-41) of
detecting a sudden rise in the correlator chain output would have suggested to an
artisan to monitor a signal correlator of the satellite positioning system receiver
(col. 4, ll. 39-41). Therefore, we are in agreement with the Examiner, for the
reasons set forth in the Answer, that the teachings of Shridhara would have
suggested to an artisan the invention set forth in claim 3.
For the lack of any specific arguments by Appellants, and our agreement with
the Examiner’s position, we are not persuaded of any error in the part of the
Examiner regarding the rejection of claim 3. Accordingly, the rejection of claim 3
under U.S.C. § 103(a) as being unpatentable over Shridhara in view of Beesley is
sustained.
We turn next to claim 4. Appellants assert (Br. 7) that Shridhara and Beesley
do not disclose “disabling a PN code generator of the satellite positioning system
receiver upon detecting the presence of the jamming signal.” Appellants argue
(id.) that Shridhara turns off the receiver during jamming and Beesley does not
disclose a PN code generator. We sustain the rejection of claim 4 for the reasons
we sustained the rejection of claim 1 under 35 U.S.C. § 103(a) as being
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unpatentable over Shridhara in view of Beesley, and additionally because
Shridhara discloses a PN code generator (Fig. 3) that becomes disabled when the
GPS reception is disabled.
We turn next to claim 5. We are not persuaded by Appellants’ assertion (Br. 8)
that Shridhara and Beesley do not disclose periodically monitoring a coherent
correlator output. We sustain the rejection of claim 5 for the reasons we sustained
the rejection of claim 1 under 35 U.S.C. § 103(a) as being unpatentable over
Shridhara in view of Beesley, and additionally because the disclosure in Shridhara
(col. 4, ll. 34-36) of detecting a sudden rise in the correlator chain output would
have suggested to an artisan to periodically monitor a coherent correlator output.
We turn next to claim 6. We are not persuaded by Appellants’ assertion (Br. 8)
that Shridhara and Beesley do not disclose:
blanking the satellite positioning system receiver with the blanking signal
includes at least one of disregarding an output of a signal correlator of the
satellite positioning system receiver during blanking periods, applying zero
input to the signal correlator of the satellite positioning system receiver
during blanking periods, and suspending operation of the signal correlator
operation of the satellite positioning system receiver during blanking
periods.

In Shridhara, we find that because the signal correlator (311) is integrated in
the GPS receiver (col. 6, ll. 13-17 and Fig. 3), the operation of the signal correlator
becomes suspended when the jamming signal is detected and the GPS reception is
subsequently disabled. From our review of the record, we agree with the Examiner
that the teachings of Shridhara would have suggested to an artisan the invention set
forth in claim 6, and are not convinced of any error on the part of the Examiner in
rejecting claim 6 under 35 U.S.C. § 103(a) as being unpatentable over Shridhara in
view of Beesley. Accordingly, the rejection of claim 6 is sustained.
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We turn next to claim 7. Appellants assert (Br. 9) that Shridhara and Beesley
do not teach maintaining satellite positioning system receiver signal gain during
blanking. We agree. From our review of Shridhara and Beesley, we find no
suggestion for maintaining satellite positioning system receiver signal gain during
blanking. We conclude that the prior art fails to establish a prima facie case of
obviousness of claim 7. Accordingly, we cannot sustain the rejection of claim 7
under U.S.C. § 103(a) as being unpatentable over Shridhara in view of Beesley.
We turn next to claim 8. Appellants provide no specific arguments regarding
this claim, but generally argue that Shridhara and Beesley do not disclose the
claimed features. From our review of the record, we find that Shridhara discloses
storing a satellite positioning system correlator output signal and detecting the
presence of a jamming signal in the satellite positioning system receiver by
analyzing the stored information (col. 4, ll. 39-43). Therefore, we are in agreement
with the Examiner that the teachings of Shridhara would have suggested to an
artisan the invention set forth in claim 8.
For the lack of any specific arguments by Appellants, and our agreement with
the Examiner’s position, we are not persuaded of any error in the part of the
Examiner regarding the rejection of claim 8. Accordingly, the rejection of claim 8
under U.S.C. § 103(a) as being unpatentable over Shridhara in view of Beesley is
sustained.
We turn next to claim 9, which depends from claim 8. Appellants assert (Br.
10) that none of the references analyze a stored correlator output signal to identify
a characteristic of a jamming signal and synchronize the blanking signal with the
jamming signal based on the identified characteristic. We agree. From our review
of Shridhara and Beesley, we find no suggestion for identifying a characteristic of
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a jamming signal by analyzing the stored correlator output signal and
synchronizing the blanking signal with the jamming signal based on the identified
characteristic. We conclude that the prior art fails to establish a prima facie case of
obviousness of claim 9. Accordingly, we cannot sustain the rejection of claim 9
under U.S.C. § 103(a) as being unpatentable over Shridhara in view of Beesley.
We turn next to claim 10. Appellants (Br. 10-11) repeat their argument that
there is no reason to combine Shridhara and Beesley. Thus, we sustain the
rejection of claim 10 for the reasons we sustained the rejection of claim 1 under
U.S.C. § 103(a) as being unpatentable over Shridhara in view of Beesley.
We turn next to claim 11. Because claim 11 recites subject matter similar to
the subject matter recited in claim 2, we sustain the rejection of claim 11 for the
reasons we sustained the rejection of claim 2 under U.S.C. § 103(a) as being
unpatentable over Shridhara in view of Beesley.
We turn next to claim 12. Because claim 12 recites subject matter similar to
the subject matter recited in claim 3, we sustain the rejection of claim 12 for the
reasons we sustained the rejection of claim 3 under U.S.C. § 103(a) as being
unpatentable over Shridhara in view of Beesley.
We turn next to claim 13. Because claim 13 recites subject matter similar to
the subject matter recited in claim 5, we sustain the rejection of claim 13 for the
reasons we sustained the rejection of claim 5 under U.S.C. § 103(a) as being
unpatentable over Shridhara in view of Beesley.
We turn next to claim 14. Appellants (Br. 13) assert that Shridhara and
Beesley do not disclose or suggest identifying a pulse rate and a pulse width of the
jamming signal. Appellants argue (Br. 13-14) that “Beesley fails to consider
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jamming signal characteristics.” We disagree. From our review of Beesley, we
find that the characteristics of the jamming signal are considered when the
amplitude and the rate of arrival of the jamming signal are determined. Although
Beesley discloses determining a pulse rate of the jamming signal by determining
the rate of arrival, we find no teaching in either Shridhara or Beesley to identify a
pulse width of the jamming signal. We conclude that the prior art fails to establish
a prima facie case of obviousness of claim 14. Accordingly, we cannot sustain the
rejection of claim 14 under U.S.C. § 103(a) as being unpatentable over Shridhara
in view of Beesley.
We turn next to claim 15. We are not persuaded by Appellants’ assertion (Br.
14) that Shridhara and Beesley do not disclose “creating the blanking signal based
upon the characteristic of the jamming signal.” From our review of the record, we
find that Shridhara creates a blanking signal based on the amplitude and rate of
arrival of the jamming signal (p. 2, ll. 36-38 and p. 3, ll. 104-107). Therefore, we
are in agreement with the Examiner that the teachings of Shridhara would have
suggested to an artisan the invention set forth in claim 15.
We conclude that the combined teachings of Shridhara and Beesley would
have suggested to an artisan the invention of claim 15, and are not convinced of
any error on the part of the Examiner in rejecting claim 15 under 35 U.S.C.
§ 103(a) as being unpatentable over Shridhara in view of Beesley. Accordingly,
the rejection of claim 15 is sustained.
We turn next to claim 16. Because claim 16 recites subject matter analogous to
the subject matter recited in claim 6, we sustain the rejection of claim 16 for the
reasons we sustained the rejection of claim 6 under U.S.C. § 103(a) as being
unpatentable over Shridhara in view of Beesley.
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We turn next to claim 17. Because claim 17 recites subject matter analogous to
the subject matter recited in claim 7, we cannot sustain the rejection of claim 17 for
the reasons we could not sustain the rejection of claim 7 under U.S.C. § 103(a) as
being unpatentable over Shridhara in view of Beesley.
We turn next to claim 18. Because claim 18 recites subject matter analogous to
the subject matter recited in claim 8, we sustain the rejection of claim 18 for the
reasons we sustained the rejection of claim 8 under U.S.C. § 103(a) as being
unpatentable over Shridhara in view of Beesley.
We turn next to claim 19. Appellants provide no specific arguments regarding
this claim, but generally argue that Shridhara and Beesley do not disclose the
claimed features. From our review of the record, we find that Shridhara discloses
storing a correlator output signal and identifying a characteristic of the jamming
signal by analyzing the stored signal (col. 4, ll. 39-43 and Fig. 9). Therefore, we
are in agreement with the Examiner that the teachings of Shridhara would have
suggested to an artisan the invention set forth in claim 19.
For the lack of any specific arguments by Appellants, and our agreement with
the Examiner’s position, we are not persuaded of any error in the part of the
Examiner regarding the rejection of claim 19. Accordingly, the rejection of claim
19 under U.S.C. § 103(a) as being unpatentable over Shridhara in view of Beesley
is sustained.
We turn next to claim 23. Appellants provide no specific arguments regarding
this claim, but generally argue (Br. 18) that Shridhara and Beesley do not disclose
or suggest determining a timing of a second jamming signal and synchronizing a
second blanking signal with the second jamming signal based upon the timing of
the second jamming signal. In response, the Examiner asserts (Answer 8) that
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Shridhara is not limited to one-time use of the jamming detection and jamming
countermeasure operations, but rather allow subsequent use of the two operations.
From our review of Shridhara, both of which provide receivers that are
designed to continuously detect in-coming jamming signals, we find that the
teachings of Shridhara would have suggested to an artisan to perform jamming
detection and apply countermeasures for a subsequent second jamming signal.
When detecting the second jamming signal, Beesley’s teaching of determining the
rate of arrival of the jamming signal and adjusting the blanking signal based on the
rate of arrival would have further suggested determining the timing of the second
jamming signal and synchronizing the second blanking signal with the second
jamming signal based upon the timing.
For the lack of any specific arguments by Appellants, and our agreement with
the Examiner’s position, we are not persuaded of any error in the part of the
examiner regarding the rejection of claim 23. Accordingly, the rejection of claim
23 under U.S.C. § 103(a) as being unpatentable over Shridhara in view of Beesley
is sustained.
We turn next to claim 24. Appellants assert (Br. 19) that none of the references
teach determining the relative timing of the jamming signals. Although Beesley
teaches determining the timing of jamming signals, we find no suggestion for
determining the relative timing of the jamming signals. We conclude that the prior
art fails to establish a prima facie case of obviousness of claim 24. Accordingly,
we cannot sustain the rejection of claim 24 under U.S.C. § 103(a) as being
unpatentable over Shridhara in view of Beesley.
We turn next to claim 25. Again, Appellants provide no specific arguments
regarding this claim, but generally argue (B. 20) that Shridhara and Beesley do not
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teach synchronizing the blanking signal with the jamming signal by generating a
blanking signal with a blanking characteristic that at least partially overlaps the
jamming characteristic of the jamming signal. We disagree. Beesley discloses a
blanking signal that is generated by “stretching” the detected jamming signal (p. 1,
ll. 69-72). In particular, Beesley explains that the detected noise pulse of the
jamming signal is stretched in duration and output as the blanking signal, thereby
generating a blanking signal having a pulse width wider than the pulse width of the
jamming signal (p. 3, ll. 48-55). The blanking signal that results from this process
is applied as a control signal for the blanking circuit (p. 2, ll. 1-5). The blanking
circuit functions as an attenuator and reduces the jamming signal by attenuating the
received signal in accordance with the blanking signal (id.).
From our review of Beesley, we find that in order to reduce any portion of the
jamming signal, the blanking signal must be synchronized with the jamming signal
so that it at least partially overlaps the jamming signal. Otherwise, the blanking
circuit would not have any effect on the jamming signal. For instance, instead of
attenuating the jamming signal, the blanking circuit would attenuate only those
portions of the received signal that do not include the jamming signal. This is
clearly inconsistent with the purpose of the blanking circuit, which is to reduce the
jamming signal. From the disclosures of Shridhara and Beesley, and in particular,
from Beesley’s disclosure of generating the blanking signal by stretching the
jamming signal, an artisan would have been taught to synchronize the blanking
signal with the jamming signal by generating a blanking signal with a blanking
characteristic that at least partially overlaps the jamming characteristic of the
jamming signal.
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For the lack of any specific arguments by Appellants, and our agreement with
the Examiner’s position, we are not persuaded of any error in the part of the
examiner regarding the rejection of claim 25. Accordingly, the rejection of claim
25 under U.S.C. § 103(a) as being unpatentable over Shridhara in view of Beesley
is sustained.
We turn next to claim 26. Appellants assert (Br. 19) that none of the references
teach determining the pulse rate of the jamming signal. Contrary to Appellants’
assertion, Beesley’s disclosure of determining the rate of arrival of the jamming
signal would have suggested to an artisan to determine the pulse rate of the
jamming signals. Nonetheless, we find no suggestion in Beesley for generating a
blanking signal having substantially the same pulse width and pulse rate
characteristic as the jamming signal. We conclude that the prior art fails to
establish a prima facie case of obviousness of claim 26. Accordingly, we cannot
sustain the rejection of claim 26 under U.S.C. § 103(a) as being unpatentable over
Shridhara in view of Beesley.
Next, we turn to the rejection of claims 1-19 and 23-26 under 35 U.S.C.
§ 103(a) as being unpatentable over Shridhara in view of Fielder. Regarding claim
1, the Examiner's position (Answer 3-5) is that Shridhara does not disclose that the
jamming signal has a known pattern and that a blanking signal has a pattern similar
to the jamming signal and synchronized with the jamming signal. To overcome
this deficiency of Shridhara, the Examiner turns to Fielder for a teaching of a
jamming signal having a known pattern and reducing the jamming signal with a
blanking signal having a pattern similar to and synchronized with the jamming
signal (id.).
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Appellants assert (Br. 6), inter alia, that neither Shridhara nor Fielder disclose
a blanking signal having a pattern similar to the jamming signal and synchronized
with the jamming signal.
From our review of Fielder, the reference is directed to a GPS receiver with
improved immunity to burst transmissions (col. 1, ll. 1-2). Fielder discloses
reducing a jamming signal by substituting the bit-stream of the received signal
with a locally generated bit pattern in response to the presence of an overload
signal (col. 2, ll. 40-42). The locally generated bit pattern is set so that the average
value accumulated in the correlator tends towards zero (col. 5, ll. 37-42). While
the locally generated bit pattern in Fielder can be considered a blanking signal due
to the zeroing effect it has on the correlator, we find no suggestion that the locally
generated bit pattern is similar to the jamming signal. We conclude that the prior
art fails to establish a prima facie case of obviousness of claim 1. Accordingly, we
cannot sustain the rejection of claim 1 under U.S.C. § 103(a) as being unpatentable
over Shridhara in view of Fielder.
We turn next to claims 2-9. We reverse the rejection of claims 2-9 due to their
dependency from claim 1, and the deficiencies of Fielder.
We turn next to claim 10. Appellants assert (Br. 11) that Shridhara in
combination with Fielder fail to teach synchronizing a blanking signal with a
jamming signal based upon a characteristic of the jamming signal. We agree.
From our review of Fielder, we find no suggestion for synchronizing the blanking
signal with a jamming signal based upon a characteristic of the jamming signal.
We conclude that the prior art fails to establish a prima facie case of obviousness
of claim 10. Accordingly, we cannot sustain the rejection of claim 10 under U.S.C.
§ 103(a) as being unpatentable over Shridhara in view of Fielder.
18

Appeal Number: 2006-1385
Application Number: 10/452,753

We turn next to claims 11-19. We reverse the rejection of claims 11-19 due to
their dependency from claim 10, and the deficiencies of Fielder.
We turn next to claim 23. Appellants assert (Br. 18) that Shridhara in
combination with Fielder do not teach determining a timing of a second jamming
signal and synchronizing a second blanking signal with the second jamming signal
based upon the timing of the second jamming signal. We agree. From our review
of Fielder, we find no suggestion of synchronizing a second blanking signal with a
second jamming signal based upon the determined timing of the second jamming
signal. We conclude that the prior art fails to establish a prima facie case of
obviousness of claim 23. Accordingly, we cannot sustain the rejection of claim 23
under U.S.C. § 103(a) as being unpatentable over Shridhara in view of Fielder.
We turn next to claim 24. We reverse the rejection of claim 24 due to its
dependency from claim 23, and the deficiencies of Fielder.
We turn next to claim 25. Appellants assert (Br. 20) that Shridhara in
combination with Fielder do not teach synchronizing the blanking signal with the
jamming signal so that the blanking characteristic of the blanking signal at least
partially overlaps the jamming characteristic. We agree. In Fielder, the locally
generated bit stream is set so that the average value accumulated in the correlator
tends towards zero. In particular, the locally generated bit stream is characterized
as an alternating series of +1 and -1 values and is unrelated to the characteristic of
the jamming signal. From our review of Fielder, we find no suggestion for
synchronizing the blanking signal with the jamming signal so that the blanking
characteristic of the blanking signal at least partially overlaps the jamming
characteristic. We conclude that the prior art fails to establish a prima facie case of
19

Appeal Number: 2006-1385
Application Number: 10/452,753

obviousness of claim 25. Accordingly, we cannot sustain the rejection of claim 25
under U.S.C. § 103(a) as being unpatentable over Shridhara in view of Fielder.
We turn next to claim 26. We reverse the rejection of claim 26 due to its
dependency from claim 25, and the deficiencies of Fielder.

20

Appeal Number: 2006-1385
Application Number: 10/452,753

CONCLUSION
• The decision of the examiner to reject claims 1-6, 8, 10-13, 15-16, 18-19 and
23, 25 under 35 U.S.C. § 103(a) as being unpatentable over Shridhara in
view of Beesley is affirmed. The rejection of claims 7, 9, 14, 17, 24, 26
under 35 U.S.C. § 103(a) as being unpatentable over Shridhara in view of
Beesley is reversed.
• The rejection of claims 1-19 and 23-26 under 35 U.S.C. § 103(a) as being
unpatentable over Shridhara in view of Fielder is reversed.
No time period for taking any subsequent action in connection with this appeal
may be extended under 37 CFR § 1.136(a)(1)(iv).

AFFIRMED-IN-PART

STUART S. LEVY )
Administrative Patent Judge )
)
)
)
) BOARD OF PATENT
ROBERT E. NAPPI ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
)
LINDA E. HORNER )
Administrative Patent Judge )

21

Appeal Number: 2006-1385
Application Number: 10/452,753

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