Ex parte ROM

Board of Patent Appeals and Interferences

Mar 14, 2001

08537408 (B.P.A.I. Mar. 14, 2001)

Application for patent filed October 2, 1995, entitled1
"Method And Apparatus For Maintaining Connectivity Of Nodes In
A Wireless Local Area Network," which is a continuation of
Application 08/316,078, filed September 30, 1994, now
abandoned, which is a continuation of Application 07/941,735,
filed September 8, 1992, now abandoned.
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The opinion in support of the decision being
entered today was not written for publication
and is not binding precedent of the Board.
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Paper No. 31
UNITED STATES PATENT AND TRADEMARK OFFICE

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES

Ex parte RAPHAEL ROM

Appeal No. 1997-2066
Application 08/537,4081

ON BRIEF

Before KRASS, BARRETT, and BLANKENSHIP, Administrative Patent
Judges.
BARRETT, Administrative Patent Judge.
DECISION ON APPEAL
Appeal No. 1997-2066
Application 08/537,408
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This is a decision on appeal under 35 U.S.C. § 134 from
the final rejection of claims 1-21.
We reverse.
BACKGROUND
The invention relates to a method and apparatus for
maintaining connectivity of nodes in a wireless local area
network (LAN). In conventional cellular telephone systems,
the "handoff" process of nodes between basic service areas
(BSAs), otherwise referred to as "cells," is controlled solely
by the base stations, otherwise referred to as access points
(APs). Due to the asymmetric nature of the radio links, the
node itself can best determine the quality of the signal
received at the node. In Appellant's invention, the node
determines an AP to select for reassociation after handoff.
The method of conducting the handoff is evident from claim 1,
reproduced below.
1. In a wireless local area network (LAN)
comprising a plurality of cells, each cell including at
least one access point for communicating information
between cells and at least one node for communicating via
the LAN through said access points, a method for
maintaining connectivity of a node in the wireless LAN
comprising the steps of:
Appeal No. 1997-2066
Application 08/537,408
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(a) the node selecting a second access point as a
candidate for accepting a handoff of the node from a
first access point;
(b) communicating an instruction from the node to
the first access point instructing the first access point
to relay a request to the second access point that the
second access point accept a handoff of the node from the
first access point to the second access point;
(c) directly relaying said request from the first
access point to the second access point; and
(d) performing the handoff, such that the node
communicates with the second access point.
The Examiner relies on the admitted prior art (APA) that
it was known for the handoff process to be controlled solely
by the base station (specification, p. 3, lines 6-10) and on
the following prior art:
Labedz 4,797,947 January 10,
1989
Yamauchi et al. (Yamauchi) 4,881,271 November 14,
1989
Harrison 5,181,200 January 19,
1993
(filed October 29,
1990)
Kojima et al. (Kojima) 5,323,446 June 21,
1994
(filed April 17,
1992)
Gilhousen et al. (Gilhousen) WO 91/07020 May 16,
1991
(International application published under the Patent
Cooperation Treaty)
Appeal No. 1997-2066
Application 08/537,408
The statements of the rejection have some technical2
inaccuracies. For example, the Examiner states that
"[c]laim 4 is rejected under 35 U.S.C. § 103 as being
unpatentable over Gilhousen and Labedz as applied to claims 1-
3 and 8 above, and further in view of Yamauchi . . ." (EA8).
Since claim 4 depends directly from claim 1, the statement
about "as applied to claims 1-3 and 8 above" should just be
"as applied to claim 1 above." Also, since claim 1 was
rejected only over Gilhousen, and since the Examiner only
applies Yamauchi for the limitations of claim 4, Labedz should
not be mentioned in the statement of the rejection because it
is not in the chain of dependencies of claim 4. Similar
problems exist with respect to the rejections of claims 6-10.
For example, the rejection of claims 6 and 7 should be over
Gilhousen, as applied in the rejection of claim 1, further in
view of Harrison. Nevertheless, to avoid confusion, we state
the rejections as found in the Examiner's Answer.
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The rejections, as stated by the Examiner, are:2
Claims 1-21 stand rejected under 35 U.S.C. § 112, first
paragraph, as based on a lack of enabling disclosure.
Claims 1 and 8 stand rejected under 35 U.S.C. § 102(b) as
being anticipated by Gilhousen.
Claims 1-21 stand rejected under 35 U.S.C. § 102(e) as
being clearly anticipated by Kojima.
Claim 2 stands rejected under 35 U.S.C. § 103(a) as being
unpatentable over Gilhousen in view of what was well known in
the art as exemplified by Gilhousen.
Appeal No. 1997-2066
Application 08/537,408
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Claim 3 stands rejected under 35 U.S.C. § 103(a) as being
unpatentable over Gilhousen and Labedz.
Claim 4 stands rejected under 35 U.S.C. § 103(a) as being
unpatentable over Gilhousen and Labedz, further in view of
Yamauchi.
Claim 5 stands rejected under 35 U.S.C. § 103(a) as being
unpatentable over Gilhousen, Labedz, and Yamauchi, further in
view of Gilhousen.
Claims 6 and 7 stand rejected under 35 U.S.C. § 103(a) as
being unpatentable over Gilhousen, Labedz, and Yamauchi,
further in view of Harrison.
Claim 9 stands rejected under 35 U.S.C. § 103(a) as being
unpatentable over Gilhousen, Labedz, Yamauchi, and Harrison,
further in view of the APA.
Claim 10 stands rejected under 35 U.S.C. § 103(a) as
being unpatentable over Gilhousen, Labedz, Yamauchi, and
Harrison, further in view of what was well known in the prior
art as exemplified by Gilhousen.
Claim 11 stands rejected under 35 U.S.C. § 103(a) as
being unpatentable over Gilhousen, Labedz, Yamauchi, and
Harrison.
Appeal No. 1997-2066
Application 08/537,408
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Claims 12-21 stand rejected under 35 U.S.C. § 103(a) as
being unpatentable over Gilhousen, Labedz, Yamauchi, and
Harrison as applied to claims 1-10.
We refer to the Final Rejection (Paper No. 25) and the
Examiner's Answer (Paper No. 28) (pages referred to as "EA__")
for a statement of the Examiner's position, and to the Appeal
Brief (Paper No. 27) (pages referred to as "Br__") for a
statement of Appellant's arguments thereagainst.
OPINION
35 U.S.C. § 112, first paragraph, enablement
"The test of enablement is whether one reasonably skilled
in the art could make or use the invention from the
disclosures in the patent coupled with information known in
the art without undue experimentation." United States v.
Telectronics, Inc., 857 F.2d 778, 785, 8 USPQ2d 1217, 1223
(Fed. Cir. 1988) (citing Hybritech, Inc. v. Monoclonal
Antibodies, Inc., 802 F.2d 1367, 1384, 231 USPQ 81, 94 (Fed.
Cir. 1986)). A patent need not teach, and preferably omits,
what is well known in the art. Paperless Accounting, Inc. v.
Bay Area Rapid Transit System, 804 F.2d 659, 664,
231 USPQ 649, 652 (Fed. Cir. 1986). The U.S. Patent and
Appeal No. 1997-2066
Application 08/537,408
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Trademark Office must support a rejection for lack of
enablement with reasons. In re Marzocchi, 439 F.2d 220,
223-24, 169 USPQ 367, 369-70 (CCPA 1971).
We conclude that the Examiner has not set forth
persuasive reasons to establish a prima facie case of lack of
enablement for the claimed subject matter. It is clear from
Appellant's specification that the invention is directed to an
improved way of maintaining connectivity using the structure
of a conventional wireless local area network (LAN). Thus,
the nodes, the access points, the cell arrangement, the way of
communicating between access points, etc. in the preamble of
claim 1 are all admitted to be known in the prior art. This
is not a case where the elements were not known to exist in
the prior art. Cf. In re Buchner, 929 F.2d 660,
18 USPQ2d 1331 (Fed. Cir. 1991) (no evidence that phase
comparator having four inputs and one output and divider
having two inputs and one output were known in the prior art).
The Examiner's questions (EA4) about how processing units 71,
75, 79 in figure 6 work and whether they are prior art devices
or new devices, and about how the coordinator 12 functions,
ignore the disclosed conventional nature of those elements.
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Application 08/537,408
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The Examiner fails to provide any evidence that one of
ordinary skill in the art would not have known what structure
to use to implement the hardware of the wireless LAN. In
addition, Appellant has submitted a declaration which
identifies a prior art publication by R.E. Kahn et al. (Kahn),
Advances in Packet Radio Technology, Proc. of the IEEE,
Vol. 66, No. 11, Nov. 1978, pp. 1468-1496, which discloses a
packet radio suitable for implementing both the nodes and the
access points that could be used in combination with the
method steps and apparatus of the present invention. The
Examiner finds that this is an impermissible attempt to
incorporate additional disclosure (EA14). However, it is
clear that Appellant cites the Kahn article as evidence of
knowledge of those of ordinary skill in the art, which does
not have to be put in the application. The Examiner has not
shown that the LAN was not known in the art.
The improved method and apparatus for maintaining
connectivity lies in the specific steps (method claims 1 and
11) and programming logic (claim 12) by which the node
participates in the decision as to whether it will be handed
off and, if so, to which access point. Contrary to the
Appeal No. 1997-2066
Application 08/537,408
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Examiner's suggestion (at EA13-14) that if the claimed
invention is an improvement to an existing system, the claims
should be in Jepson format under 37 CFR § 1.75(e), U.S. patent
law does not compel that claims be put in Jepson format. The
Examiner has not established that one of ordinary skill in the
art would have been unable to implement the claimed method
steps or programming logic without undue experimentation. For
example, the Examiner does not explain why one of ordinary
skill in the art would have been unable to program a node to
perform the step of "(a) the node selecting a second access
point as a candidate for accepting a handoff of the node from
a first access point" (claim 1) without undue experimentation.
The specification discloses that the node might make this
determination based on the quality of the signal
(specification, p. 9). Appellant's declaration, paragraph 8,
notes that the Kahn article describes that there are several
ways a packet radio can determine the quality of a radio link
and, based upon this disclosure, it was within the level of
ordinary skill in the art to build a node packet radio
programmed to select another packet radio (a second access
point) as a candidate for handoff. Moreover, Gilhousen
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Application 08/537,408
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discloses step (a) without any description of structure; thus,
Gilhousen presumes the implementation is within the level of
ordinary skill in the art. Nor has the Examiner explained why
steps (b) through (d) of claim 1 would not have been enabling
to one having ordinary skill in the art and has not addressed
Appellant's declaration, paragraphs 9 and 10, as to the
enablement of these limitations.
In conclusion, the Examiner has failed to establish a
prima facie case of lack of enablement. The rejection of
claims 1-21 under § 112, first paragraph, is reversed.
35 U.S.C. § 102(e) over Kojima
Appellant argues that Kojima fails to teach or suggest:
(1) communicating an instruction from the node to the first
access point instructing the first access point to relay a
request to the second access point that the second access
point accept a handoff of the node from the first access point
to the second access point; and (2) directly relaying said
request from the first access point to the second access
point, which are steps (b) and (c) of claim 1. It is argued
that Kojima teaches a node sending switching requests directly
to both the first and second access point and, thus, there is
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Application 08/537,408
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no teaching of requesting the first access point to relay a
request and there is no relaying of any request from the first
access point to the second access point (Br8).
With respect to the relevant limitations, the Examiner
repeats the findings of the final rejection (EA6):
The mobile station (node) selects a second base station
([second] access point) based on signal strength and
communicates a request (instruction) to a first base
station ([first] access point) to handoff between base
stations (col. 1, line 45-col. 2, line 43; Figures 1, 2,
8A-8D). The first base station ([first] access point)
relays the request to the second base station ([second]
access point) through a system controller 11 (col. 3,
lines 3-35).
Kojima discloses (col. 6, lines 3-17):
If the cordless station is leaving the cell of base
station 20 and entering the cell of base station 201 2
. . . the controller of cordless station 40 . . . selects
a second, idle timeslot to establish a radio channel with
base station 20 and transmits a channel switching request2
signal. This request signal is received by base stations
20 and 20 and passed to CLIC's 14 and 14 of PBX 10 and1 2 1 2
thence to main controller 11. When this occurs, the
speech signal from cordless station 40 is also carried on
the second timeslot and it reaches a terminal of the
time-division switch 12 through path 40', while it is
being transported on path 40a through base station 20 .1
Figure 8A shows the request going from the cordless station 40
to both base stations 20 and 20 . It is clear that Kojima1 2
transmits a channel switching request signal to both the
current base station 20 (first access point) and the1
Appeal No. 1997-2066
Application 08/537,408
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requested base station 20 (second access point). Kojima does2
not send a request to accept a handoff to the current base
station 20 (first access point), with a request to relay the1
request to base station 20 (second access point), and no2
request is relayed, directly or otherwise, from base station
20 (first access point) to base station 20 (second access1 2
point). Therefore, the Examiner erred in finding that Kojima
anticipates the limitations of steps (b) and (c) of
independent claim 1, which limitations find direct
correspondence in independent claims 11 and 12. Accordingly,
the rejection of claims 1-21 is reversed.
35 U.S.C. § 102(b) over Gilhousen
Appellant argues that Gilhousen fails to teach or
suggest: (1) communicating an instruction from the node to
the first access point instructing the first access point to
relay a request to the second access point that the second
access point accept a handoff of the node from the first
access point to the second access point; and (2) directly
relaying said request from the first access point to the
second access point, which are steps (b) and (c) of claim 1.
It is argued that Gilhousen teaches a mobile unit (node)
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Application 08/537,408
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sending a signal to its current cell-site (first access point)
requesting a handoff which is forwarded to a system
controller, which performs the handoff, but there is no
evidence that the request is forwarded directly or otherwise
from the first access point to the second access point (Br9).
The Examiner finds that "[t]he first cell-site ([first]
access point) relays the request to the second cell-site
([second] access point) through a system controller 10
(page 6, line 33-page 7, line 1)" (EA6).
Gilhousen discloses that the request for handoff to a new
cell-site is relayed to the system controller 10 and the
system controller handles the handoff process by assigning a
modem in the new cell-site (second access point) and giving it
information about the call (p. 6, line 17 to p. 7, line 1; p.
12, lines 20-32). The system controller 10 is not a second
access point. The Examiner errs in finding that the request
is relayed "through" the system controller 10 to a second
access point.
The Examiner further states (EA18):
[T]he phrase "directly relaying" should be interpreted to
mean a communication which is transmitted by means of the
LAN as a whole from one point to another. The fact that
the communication may temporarily be held in a hub,
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Application 08/537,408
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router, or another node (i.e., token bus/loop repeater)
is transparent to the transmission operation, what is
important is that any communication sent from the first
point to the next is not modified by a relaying unit
along the way to change the content of the message and
its purpose. Gilhousen, Kojima, and Harrison
transparently relay any messages sent into the network
from one point to another without changing the content of
the messages. Thus, both Gilhousen and Kojima operate in
the manner indicated by the Applicant's disclosure and
the Examiner maintains that the rejections made based
upon Gilhousen or Kojima, respectively, are proper.
We agree with the Examiner that the phrase "directly
relaying" does not exclude going unchanged through
intermediate nodes (a node in the sense of a junction between
two connectors, as opposed to the mobile nodes). However,
under the Examiner's own interpretation of "directly relaying"
as not allowing any modification of the message, the handoff
request is not directly relayed or passed "through" the system
controller 10 in Gilhousen because it is the system controller
which handles the request, not the second cell-site (second
access point). It is true that Gilhousen discloses a mobile
initiated handoff, but the implementation is not the same as
what is claimed. This difference in implementation is
commented on in Appellant's declaration regarding the
enablement rejection (paragraph 9):
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Application 08/537,408
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The first access point can be programmed to relay the
request directly to the second access point without the
intervention of a central system controller. The choice
of whether to relay the request directly between access
points or use a central controller is a matter of
programming a microprocessor-based packet radio to
achieve the desired communications function.
Because we find that Gilhousen does not teach
(1) communicating an instruction from the node to the first
access point instructing the first access point to relay a
request to the second access point that the second access
point accept a handoff of the node from the first access point
to the second access point, and (2) directly relaying said
request from the first access point to the second access
point, the Examiner has failed to establish a prima facie case
of anticipation. The anticipation rejection of claims 1 and 8
is reversed.
35 U.S.C. § 103(a)
The Examiner rejects claims 2-11 over Gilhousen in
combination with one or more of Labedz, Yamauchi, Harrison,
the APA, and what was well known in the art. We find that the
added prior art does not cure the deficiencies with respect to
Gilhousen. Thus, the rejections of claims 2-11 are reversed.
Appeal No. 1997-2066
Application 08/537,408
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The Examiner finds that limitations of apparatus
claims 12-21 track the steps of method claims 1-10 and rejects
claims 12-21 for the reasons stated with respect to
claims 1-10. The Examiner concludes that the apparatus is
simply a logical implementation of the steps disclosed in the
references (EA12). Because Gilhousen does not disclose the
function of "forming an instruction instructing said first
access point to relay a request to said second access point
requesting that said second access point accept a handoff of
said node from said first access point, and causing said
instruction to be communicated to said first access point" in
claim 12, which is similar to steps (b) and (c) of claim 1,
discussed supra, the rejection of claim 12 is reversed.
Because the additional prior art to Labedz, Yamauchi,
Harrison, the APA, and what was well known in the art does not
cure the deficiencies of Gilhousen, the rejections of
dependent claims 13-21 are reversed.
CONCLUSION
The rejections of claims 1-21 are reversed.
REVERSED
Appeal No. 1997-2066
Application 08/537,408
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ERROL A. KRASS )
Administrative Patent Judge )
)
)
)
) BOARD OF PATENT
LEE E. BARRETT ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
)
HOWARD B. BLANKENSHIP )
Administrative Patent Judge )
Appeal No. 1997-2066
Application 08/537,408
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