UNITED STATES PATENT AND TRADEMARK OFFICE
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`BEFORE THE PATENT TRIAL AND APPEAL BOARD
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`INTEL CORPORATION,
`Petitioner,
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`v.
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`UNM RAINFOREST INNOVATIONS,
`Patent Owner.
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`
`
`
`PTAB Case No. IPR2020-01576
`Patent No. 8,265,096 B2
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`
`
`
`
`
`PETITION FOR INTER PARTES REVIEW
`OF U.S. PATENT NO. 8,265,096 B2
`
`Claims 1-4 and 6-8
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`

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`TABLE OF CONTENTS
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`Page
`INTRODUCTION ........................................................................................ 1 
`I. 
`II.  MANDATORY NOTICES .......................................................................... 2 
`A.  Real Parties in Interest ...................................................................... 2 
`B. 
`Related Matters .................................................................................. 2 
`C.  Notice of Counsel and Service Information ..................................... 3 
`III.  REQUIREMENTS FOR INTER PARTES REVIEW ............................... 4 
`A. 
`Standing ............................................................................................... 4 
`B. 
`Challenge Grounds ............................................................................. 4 
`IV.  THE BOARD SHOULD NOT DENY INSTITUTION FOR
`DISCRETIONARY REASONS .................................................................. 5 
`V.  OVERVIEW OF THE ’096 PATENT ........................................................ 9 
`A. 
`Background: History of Broadband Wireless and the
`IEEE 802.16 WiMAX Standards ...................................................... 9 
`The ’096 Patent Discloses Constructing a Frame
`Structure to Provide Compatibility between 802.16
`Systems and Mobility Support ........................................................ 14 
`The Challenged Claims of the ’096 Patent ..................................... 17 
`Priority Date and Prosecution History of the ’096
`Patent ................................................................................................. 18 
`Level of Ordinary Skill in the Art .................................................. 21 
`E. 
`Claim Construction .......................................................................... 21 
`F. 
`VI.  OVERVIEW OF THE PRIOR ART RELIED UPON IN THIS
`PETITION ................................................................................................... 23 
`A. 
`Talukdar ............................................................................................ 23 
`
`C. 
`D. 
`
`B. 
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`

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`Li ........................................................................................................ 28 
`B. 
`C.  Nystrom ............................................................................................. 30 
`VII.  ARGUMENT: THE CHALLENGED CLAIMS OF THE ’096
`PATENT ARE UNPATENTABLE OVER THE PREVIOUSLY-
`UNCONSIDERED PRIOR ART RAISED HERE .................................. 32 
`A.  Ground 1: Talukdar and Li Rendered Claims 1-4
`and 6-7 Obvious ................................................................................ 33 
`1. 
`Claim 1 .................................................................................... 33 
`2. 
`Claim 2 .................................................................................... 54 
`3. 
`Claim 3 .................................................................................... 56 
`4. 
`Claim 4 .................................................................................... 57 
`5. 
`Claim 6 .................................................................................... 59 
`6. 
`Claim 7 .................................................................................... 60 
`B.  Ground 2: Talukdar and Nystrom Rendered Claim 8
`Obvious .............................................................................................. 62 
`VIII.  CONCLUSION ........................................................................................... 70 
`
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`

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`EXHIBIT LIST
`
`Ex. 1007
`
`Ex. 1004
`
`Description
`Exhibit
`Ex. 1001 U.S. Patent No. 8,265,096 (“the ’096 patent”)
`Ex. 1002 Declaration of Dr. Robert Akl (“Akl”)
`Ex. 1003 Sand Revolution II, LLC v. Continental Intermodal
`Group-Trucking LLC, Paper 24, IPR2019-01393 (PTAB June 16,
`2020)
`Seventh Supplemental Order Regarding Court Operations Under Exi-
`gent Circumstances Created by the Covid 19 Pandemic (W.D. Tex.
`Aug. 6, 2020)
`Ex. 1005 Excerpts from JEFFREY G. ANDREWS ET AL.,
`FUNDAMENTALS OF WIMAX (2007)
`Ex. 1006 Five Criteria Statement for P802.16m PAR Proposal,
`IEEE 802.16-06/055r3 (Nov. 15, 2006)
`IEEE 802.16m System Requirements, IEEE 802.16m-07/002r4 (Oct.
`19, 2007)
`Ex. 1008 Listing of Challenged ’096 Patent Claims
`Ex. 1009 U.S. Provisional App. No. 60/929,798
`Ex. 1010 Excerpts from ’096 Patent File History
`Ex. 1011 Claim Construction Order in STC.UNM v. Apple Inc., No. 1-20-cv-
`00351 (W.D. Tex. Apr. 9, 2020), ECF No. 69 (“Markman Order”)
`Ex. 1012 U.S. Pub. No. 2009/0067377 A1 (“Talukdar”)
`Ex. 1013 U.S. Provisional Application No. 60/956,031
`(“Talukdar Provisional”)
`Ex. 1014 Canadian Patent Application No. 2 581 166 A1 (“Wang”)
`Ex. 1015 WIPO Handbook on Industrial Property Information and Documen-
`tation, “Examples and Kinds of Patent Documents” (May 2016)
`Ex. 1016 U.S. Pub. No. 2007/0155387 A1 (“Li”)
`Ex. 1017 U.S. Pub. No. 2007/0104174 A1 (“Nystrom”)
`Ex. 1018 U.S. Pub. No. 2008/0095195 (“Ahmadi”)
`
`

`

`Description
`Exhibit
`Ex. 1019 Excerpts from William Stallings, WIRELESS COMMUNICATIONS AND
`NETWORKS (2D ED. 2005)
`Ex. 1020 U.S. Patent No. 7,460,466 B2 (“Lee”)
`Ex. 1021 U.S. Patent No. 8,462,611 B2 (“Ma”)
`Ex. 1022 Fixed, nomadic, portable and mobile applications for 802.16-2004
`and 802.16e WiMAX networks (November 2005)
`Ex. 1023 Mohammad Azizul Hasan, Performance Evaluation of Wi-
`MAX/IEEE 802.16 OFDM Physical Layer (June 2007)
`Ex. 1024 U.S. Patent No. 7,710,910 B2 (“Ode”)
`Ex. 1025
`IEEE 802.16m System Requirements,
`IEEE 802.16m-07/002r4 (Jan. 12, 2007)
`Ex. 1026 U.S. Pub. No. 2004/0037215 A1 (“Hwang”)
`Ex. 1027 Yasamin Mostofi, ICI Mitigation for Pilot-Aided OFDM Mobile Sys-
`tems (IEEE, Vol. 4, No. 2, Mar. 2005)
`
`
`
`

`

`
`Petition for Inter Partes Review of ’096 Patent (IPR2020-01576)
`
`
`INTRODUCTION
`Patent Owner UNM Rainforest Innovations acquired U.S. Patent No.
`
`
`I.
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`8,265,096 (Ex. 1001, “the ’096 patent”) from the Industrial Technology Research
`
`Institute of Taiwan and has asserted it, along with several other patents relating to
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`5
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`wireless technology, against Petitioner Intel’s Wi-Fi chip customers. Petitioner re-
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`quests that the Board institute inter partes review of claims 1-4 and 6-8 of the ’096
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`patent (the “challenged claims”) because, as shown below, those claims were un-
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`patentable over the prior art discussed in this Petition but not considered by the Ex-
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`aminer during the original prosecution.
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`10
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`The ’096 patent describes methods for constructing a data transmission frame
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`structure with sections formatted for two communication systems, one of which sup-
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`ports higher mobility than the other. The frame includes a first section comprising
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`data formatted for the first system; a second section comprising data formatted for
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`the second, higher-mobility system; and a non-data section that describes some as-
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`15
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`pect of data in one of the sections. To support higher mobility, the second system
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`has a shorter symbol period or denser pilot symbols than the first system.
`
`During prosecution of the ’096 patent application, the Examiner did not ap-
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`preciate that every aspect of the claimed methods was known in the prior art.
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`Motorola had previously filed a patent application that described frame structures
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`-1-
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`

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`Petition for Inter Partes Review of ’096 Patent (IPR2020-01576)
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`
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`with data sections formatted for different communication systems. Four years be-
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`fore the ’096 patent, Ericsson engineers had filed a patent application disclosing a
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`system that used denser pilot symbols for higher-mobility users. And two years
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`before the ’096 patent, Intel engineers had filed a patent application disclosing a
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`5
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`system that used a shortened symbol period for higher-mobility users.
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`The Patent Office did not have the benefit of considering these references dur-
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`ing prosecution. As shown below, all limitations of the challenged claims were
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`known and obvious before the ’096 patent. IPR should therefore be instituted, and
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`the challenged claims should be cancelled.
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`10
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`II. MANDATORY NOTICES
`A. Real Parties in Interest
`Intel Corporation files this Petition because UNM Rainforest Innovations has
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`sued Intel customers for infringing the ’096 patent. Intel has had sole control over
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`this Petition and is the real party in interest for this Petition. For completeness, Intel
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`15
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`also identifies its customers Dell Technologies Inc., Dell Inc., and EMC Corporation
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`(collectively, “Dell”), which have been named as defendants in a pending litigation
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`involving the ’096 patent, as additional real parties in interest for this Petition.
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`B. Related Matters
`Patent Owner, which was formerly named STC.UNM, has asserted certain
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`20
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`claims of the ’096 patent in the following pending district-court lawsuits: UNM
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`-2-
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`

`
`Petition for Inter Partes Review of ’096 Patent (IPR2020-01576)
`
`
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`Rainforest Innovations v. ASUSTek Computer, Inc., No. 6:20-cv-00142 (W.D. Tex.);
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`UNM Rainforest Innovations v. Dell Techs. Inc. et al., No. 6:20-cv-00468 (W.D.
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`Tex.); UNM Rainforest Innovations v. D-Link Corp., No. 6:20-cv-00143 (W.D.
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`Tex.); UNM Rainforest Innovations v. TP-Link Techs. Co., No. 6:19-cv-00262 (W.D.
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`5
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`Tex.); and UNM Rainforest Innovations v. ZyXEL Commc’ns Corp., No. 6:20-cv-
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`00522 (W.D. Tex.).1
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`C. Notice of Counsel and Service Information
`Petitioner’s counsel are:
`
`Lead Counsel
`Christina J. McCullough
`(Reg. No. 58,720)
`cmccullough@perkinscoie.com
`PERKINS COIE LLP
`1201 Third Avenue, Suite 4900
`Seattle, Washington, 98101
`(206) 359-8000 (phone)
`
`
`Back-Up Counsel
`Brianna Kadjo (Reg. No. 74,307)
`bkadjo@perkinscoie.com
`PERKINS COIE LLP
`1900 Sixteenth Street, Suite 1400
`Denver, CO 80202
`(303) 291-2300
`
`
`
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` 1
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` Patent Owner also asserted the ’204 patent in UNM Rainforest Innovations v. Apple
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`Inc., No. 1:20-cv-00351 (W.D. Tex.) (“the Apple litigation”), which was recently
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`dismissed. See Dkt. #80 (Aug. 5, 2020).
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`
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`-3-
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`

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`Petition for Inter Partes Review of ’096 Patent (IPR2020-01576)
`
`
`
`
`Lead Counsel
`
`Back-Up Counsel
`Sarah Piepmeier
` (pro hac vice application forthcoming)
`spiepmeier@perkinscoie.com
`PERKINS COIE LLP
`505 Howard Street, Suite 1000
`San Francisco, CA 94105
`(415) 344-7000 (phone)
`
`Petitioner is filing a Power of Attorney appointing the above-named counsel
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`and consents to electronic service at:
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`Intel-STC.UNM-Service-IPR@perkinscoie.com.
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`5
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`III. REQUIREMENTS FOR INTER PARTES REVIEW
`A.
`Standing
`The ’096 patent qualifies for IPR, and Petitioner is not barred from request-
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`ing review.
`
`B. Challenge Grounds
`Claims 1-4 and 6-8 of the ’096 patent were obvious on the following grounds:
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`Ground
`1
`2
`
`Basis for Obviousness
`Talukdar (Ex. 1012) and Li (Ex. 1016)
`Talukdar and Nystrom (Ex. 1017)
`
`Challenged Claims
`1-4, 6-7
`8
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`10
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`Talukdar, Li, Nystrom, and other references also illustrate the state of the art
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`at the time of the alleged invention. See Ariosa Diagnostics v. Verinata Health, Inc.,
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`805 F.3d 1359, 1365 (Fed. Cir. 2015) (“Art can legitimately serve to document the
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`-4-
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`

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`Petition for Inter Partes Review of ’096 Patent (IPR2020-01576)
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`
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`knowledge that skilled artisans would bring to bear in reading the prior art identified
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`as producing obviousness.”) (citation omitted).
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`The Declaration of Dr. Robert Akl (Ex. 1002, cited as “Akl” below) and other
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`evidence cited therein and in the Exhibit List further support this Petition.
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`5
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`IV. THE BOARD SHOULD NOT DENY INSTITUTION FOR
`DISCRETIONARY REASONS
`A discretionary denial would be inappropriate here. Section 325 does not
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`apply, because this is the first Petition filed against this patent by any party, and it
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`raises prior art not cited or considered during prosecution to support entirely new
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`10
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`arguments.
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` Section 314 likewise does not support denial. Petitioner Intel is not a party
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`in any of the litigations involving the challenged patent. See § II(B) (identifying
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`litigations). Although § 314 gives the Director discretion regarding IPR petitions, it
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`does not appear to give the Director unfettered discretion to deny an otherwise
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`15
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`meritorious petition, particularly when the Petitioner has no other legal options
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`regarding a patent—as is the case here. Further, although Petitioner recognizes that
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`RPI Dell is a defendant in one action, UNM Rainforest Innovations v. Dell
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`Technologies Inc. et al., No. 6:20-cv-00468 (W.D. Tex.) (“the Dell litigation”), the
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`factors set out in Apple, Inc. v. Fintiv, Inc., Paper 11, IPR2020-00019 (PTAB Mar.
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`20
`
`20, 2020) (precedential) favor proceeding with this Petition.
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`-5-
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`

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`Petition for Inter Partes Review of ’096 Patent (IPR2020-01576)
`
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`Fintiv factor 1, likelihood of a stay. The district court has not considered
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`
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`whether a stay would be appropriate in any of the litigations. Absent specific
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`evidence regarding a potential stay, the Board “will not attempt to predict” how the
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`court will proceed. Sand Revolution II, LLC v. Continental Intermodal Group-
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`5
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`Trucking LLC, IPR2019-01393, Paper 24 at 7 (PTAB June 16, 2020) (informative)
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`(Ex. 1003). This factor is therefore neutral. Id.
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`Fintiv factor 2, trial date proximity to Final Written Decision (FWD). The
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`FWD will issue well before the trial dates for the vast majority of the litigations. In
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`most cases, Patent Owner has either failed to serve the complaint or served it just
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`10
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`last month. The Dell litigation is the only case in which the Court has set a trial date.
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`There, the court scheduled the Markman hearing for February 2021 and trial for
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`November 2021. Although this ostensibly places the trial date before the expected
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`FWD date, the Board has recognized that trial dates are often amended and continued,
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`particularly as the calendared dates approach. Sand Revolution, Paper 24 at 9
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`15
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`(uncertainty of expected trial date weighed against exercising discretion to deny
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`institution). A trial date that is more than a year away is inherently uncertain.2
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` 2
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` In an unrelated Western District of Texas litigation involving Petitioner, the district
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`court has set the same estimated trial date as the Dell date. This further confirms the
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`Petition for Inter Partes Review of ’096 Patent (IPR2020-01576)
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`Further, the Western District of Texas has not been holding any trials due to the
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`COVID-19 pandemic. See Seventh Supplemental Order Regarding Court Operations
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`Under the Exigent Circumstances Created by the COVID-19 Pandemic (W.D. Tex.
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`Aug. 6, 2020) (Ex. 1004). The resulting backup of cases, including criminal cases
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`5
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`that will take priority over civil cases, creates significant uncertainty about trial dates
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`in later cases like this one. This factor is therefore neutral.
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`Fintiv factor 3, investment in the parallel proceedings. The “investment in
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`the parallel proceeding by the court and the parties” (Fintiv at 10) weighs heavily
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`against denial. The litigations have only just begun. The court and parties have
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`10
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`made little to no investment. In most cases, Patent Owner has either failed to serve
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`the complaint or served it only within the past four weeks. Although the court issued
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`a three-page Markman order (Ex. 1011) in the prior Apple litigation, that order had
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`no substantive analysis. Sand Revolution at 10-11 (two-page Markman Order did
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`not demonstrate a high level of investment of time and resources). Further,
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`15
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`Petitioner acted expeditiously by filing this petition shortly after its customer Dell
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`was sued. Fintiv at 11. This factor weighs against discretionary denial.
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`
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`uncertainty of any Dell trial date; plainly, the court cannot simultaneously adjudicate
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`two patent trials.
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`-7-
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`Petition for Inter Partes Review of ’096 Patent (IPR2020-01576)
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`Fintiv factor 4, overlap of issues. The invalidity grounds, arguments, and
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`
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`evidence presented in this Petition will be different than those presented in the
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`litigations. This Petition challenges claims (claims 2 and 7), which are not asserted
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`in any of the litigations. Further, Dell has indicated that it will stipulate in the Dell
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`5
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`litigation, prior to any trial in which Dell products that incorporate Petitioner’s Wi-
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`Fi components are accused of infringement, that if the Board institutes IPR of the
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`challenged claims, Dell will not pursue invalidity of the challenged claims on the
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`same grounds or even the same references at issue in this Petition. This mitigates
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`the concerns of duplicated efforts and conflicting decisions. See VMware, Inc. v.
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`10
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`Intellectual Ventures I LLC, IPR2020-00470, Paper 13 at 20 (PTAB Aug. 18, 2020)
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`(finding that a similar stipulation “mitigates any concerns of duplicative efforts
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`between the district court and the Board, as well as concerns of potentially
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`conflicting decisions”). This factor weighs against discretionary denial.
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`Fintiv factor 5, whether petitioner and defendant are the same. This factor
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`15
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`weighs against discretionary denial when the petitioner is not the same party as the
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`defendant. Fintiv at 13 (considering “whether the petitioner and the defendant in the
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`parallel proceeding are the same party”); id. at 11, n.20 (“If the parallel litigation
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`involves a party different than the petitioner, this fact weighs against exercising
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`authority to deny institution[.]”). Intel is not a defendant in any of the litigations,
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`-8-
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`Petition for Inter Partes Review of ’096 Patent (IPR2020-01576)
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`and Intel is not the same party as any defendant. This factor therefore weighs against
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`denial.
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`Fintiv factor 6. The “other circumstances that impact the Board’s exercise of
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`discretion, including the merits” (Fintiv at 6, 14-15) heavily favor institution,
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`5
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`because the grounds raised in the Petition are particularly strong: the prior art
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`demonstrates unpatentability based on references that have not been considered by
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`the Board or Examiner that would have been combined by skilled artisans as asserted
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`for compelling reasons. Further, Petitioner Intel has no legal recourse with respect
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`to this patent outside of IPR. These circumstances weigh against discretionary
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`10
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`denial.
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`The Fintiv factors, viewed holistically, demonstrate that instituting review in
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`this matter would promote efficiency and integrity of the system. Fintiv at 6.
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`Discretionary denial under § 314 is not appropriate.
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`15
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`V. OVERVIEW OF THE ’096 PATENT
`A. Background: History of Broadband Wireless and the
`IEEE 802.16 WiMAX Standards
`From the 1990s into the early 2000s, the popularity of wireless cellular com-
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`munication systems and wired broadband communication systems grew exponen-
`
`tially. Both systems were widely adopted, but they were distinct.
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`20
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`Cellular wireless systems typically included a number of mobile stations (e.g.,
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`cellular telephones) and fixed base stations that communicated wirelessly with the
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`

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`Petition for Inter Partes Review of ’096 Patent (IPR2020-01576)
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`
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`mobile stations. Akl ¶ 52. Base stations received communications from mobile
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`stations and helped route the communications to intended destinations, which could
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`be telephones on the public wired telephone network or other mobile stations on a
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`network like the Internet. Cellular wireless systems allowed users to stay connected
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`5
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`even while moving and were used primarily for voice calls and low-bitrate applica-
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`tions. Akl ¶ 54. Broadband systems, on the other hand, typically involved user
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`equipment with more computational power (e.g., personal computers) connected
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`over a wireline medium to the Internet or a local network. Id. Broadband systems
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`provided users with significantly higher bandwidth than wireless systems and facil-
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`10
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`itated data-heavy applications like Internet browsing, file downloading, and media
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`streaming.
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`In 1998, the Institute of Electrical and Electronics Engineers (IEEE) formed
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`the 802.16 group, which sought to combine broadband-level service with wireless
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`techniques in the “WiMAX” standard. Akl ¶ 63. The group released a first 802.16
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`15
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`standard in 2001 and established the WiMAX Forum to promote certification efforts.
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`Id. ¶¶ 63-65. In 2003, the group amended the standard to add support for multipath
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`environments, where the signal arriving at a receiver contained reflected radio waves
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`arriving via different paths. Id. ¶¶ 63-64. The air interface for 802.16 was based on
`
`orthogonal frequency division multiplexing (OFDM) techniques, which allowed a
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`
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`-10-
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`Petition for Inter Partes Review of ’096 Patent (IPR2020-01576)
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`transmission to be sent over a large frequency bandwidth divided into multiple over-
`
`lapping but orthogonal sub-carrier frequencies (often called “subcarriers”). Id.
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`¶¶ 71-73. At the time, OFDM was the dominant technique for handling broadband
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`multipath scenarios. Id. ¶ 71.
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`5
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`But broadband wireless still could not provide the high-throughput data rates
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`of traditional broadband services. Akl ¶ 54, 58. The 802.16 group understood that
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`adoption of broadband wireless would depend largely on their ability to differentiate
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`it based on features such as portability and mobility, which traditional broadband
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`could not offer. Id. The group thus began work on revisions to the 802.16 standard
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`10
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`that were focused on providing mobility support. Id.
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`The first 802.16 revision that included mobility support was published in 2005
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`as 802.16(e). Akl ¶ 64. The 802.16(e) revision defined a mobile system profile
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`(called “Mobile WiMAX”) that used OFDM to support user equipment moving at
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`up to vehicular speeds. Id. The 802.16(e) revision also used orthogonal frequency
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`15
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`division multiple access (OFDMA)—a
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`technique
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`that allowed sub-carrier
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`frequencies to be allocated among multiple users—to scale the data rate based on
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`the available channel bandwidth. Akl ¶¶ 75-76.
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`The 802.16(e) revision specified a default frame structure for data
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`transmissions:
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`Petition for Inter Partes Review of ’096 Patent (IPR2020-01576)
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`Ex. 1005 (“Fundamentals of WiMAX”) at 45; Akl ¶ 68. As shown above, an 802.16
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`frame included downlink (DL) subframes, which were used for communications
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`from the base station to mobile stations, and uplink (UL) subframes, which were
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`5
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`used for communications from mobile stations to the base station. Id. ¶¶ 68-69. The
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`downlink subframe began with a preamble that included information used for time
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`and frequency synchronization and channel estimation. Id. A frame control header
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`(FCH) and downlink and uplink MAP messages (DL-MAP, UL-MAP) followed. Id.
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`The FCH provided frame configuration information such as the length of the MAP
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`10
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`messages, the modulation and coding schemes used for the frame data, and the
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`Petition for Inter Partes Review of ’096 Patent (IPR2020-01576)
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`usable subcarriers. Id. The DL-MAP and UL-MAP messages specified which data
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`regions within the frame were allocated to which users, as well as data modulation
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`and coding schemes. Id.
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`Mobility support created implementation challenges, particularly for OFDM
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`5
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`systems. Faster-moving user devices experienced frequently-changing channel
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`conditions, Doppler spreads, and higher levels of interference between OFDM
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`subcarriers. Akl ¶ 81. Wireless systems typically used “pilot” symbols—symbols
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`with a known value and format, transmitted at known intervals—to perform channel
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`estimation, which helped compensate for these issues. Id. But devices traveling at
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`10
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`vehicular speeds did not always receive pilot symbols frequently enough for channel
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`estimation purposes.
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`In 2006, the 802.16 group began developing another mobility-focused
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`revision, 802.16(m), which supported higher data rates for mobility scenarios and
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`improved the levels and quality of service of cell coverage. Akl ¶ 66. During
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`15
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`development, the 802.16 group specified that 802.16(m) would also support legacy
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`802.16(e) systems. Id. The 802.16(m) revision was released in 2011. Id.
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`Thus, by the mid-2000s—well before the ’096 patent—providing mobility
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`support in broadband wireless systems was a known goal. The IEEE had identified
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`mobility as a key objective for broadband wireless systems in the 802.16(e) standard,
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`which it released in 2005. The 802.16(m) standard, begun in 2006, extended
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`mobility support in a manner consistent with cellular standards. Implementation-
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`level details were left to equipment manufacturers and telecommunications
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`providers to develop more fully.
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`B.
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`The ’096 Patent Discloses Constructing a Frame
`Structure to Provide Compatibility between 802.16
`Systems and Mobility Support
`Consistent with these industry efforts, the named inventors of the ’096 patent
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`described a frame structure for 802.16 systems that provided enhanced mobility sup-
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`port. The ’096 patent recognizes the default frame structure defined by the 802.16
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`standard:
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`’096 patent, Fig. 1; id. at 1:28-31, 1:36-37. As discussed above (supra at 11-13), an
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`802.16 frame included a downlink subframe and an uplink subframe (subframes 16
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`and 18, respectively, in Figure 1). ’096 patent at 1:37-39. The downlink subframe
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`included sections for user data (DATA 14-1) and non-data information (preamble
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`10-1, FCH 11, and DL-MAP 12). Id. at 1:46-49.
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`The ’096 patent observes that 802.16(m), which was under development when
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`the ’096 patent application was filed, would require “full backward compatibility
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`with the legacy system defined in the IEEE Standard 802.16e” and provide “higher
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`speed tolerance” than 802.16(e). Id. at 1:30-35; supra, § IV(A). The patent proposes
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`an amended frame structure that addresses these compatibility and mobility require-
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`ments.
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`To address backward compatibility, the patent calls for splitting the downlink
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`and uplink subframes into two zones: a first zone containing data formatted for a
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`first system (e.g., a user device compliant with 802.16(e)), and a second zone con-
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`taining data formatted for a second system (e.g., an 802.16(m) device):
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`Id., Fig. 3 (downlink Zones 1 and 2 (30-1, 30-2), uplink Zones 1 and 2 (34-1, 34-2));
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`id. at 4:21-67. The frame retains the standard non-data portions of the 802.16 format,
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`including the preamble, FCH, and DL-MAP. Id., Fig. 3 (preamble 10-11, FCH 11,
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`DL-MAP 12); id. at 4:40-46, 4:57-67; Akl ¶ 84.
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`To address mobility support, the ’096 patent describes creating a zone for the
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`second system with a modified symbol structure. ’096 patent, Fig. 4 & 5:1-16. The
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`patent observes that shortening the duration of symbols could improve mobility sce-
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`narios, because “a shorter symbol period may be more robust to inter-symbol inter-
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`ference” experienced by faster-moving devices. Id. at 5:16-17. Alternatively, in-
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`creasing the density of pilot symbols could improve mobility support because
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`“denser pilot symbols may achieve better channel estimation accuracy.” Id. at 5:17-
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`18. The patent thus proposes incorporating either scheme into the new system zone:
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`“zones … for the new system … under higher mobility … may have a shorter symbol
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`period or more pilot symbols placed therein” than the zones for the older system. Id.
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`at 5:8-14; id., Figure 7 & 7:38-8:6.
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`C. The Challenged Claims of the ’096 Patent
`The challenged claims of the ’096 patent cover methods for constructing
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`frame structures. Independent claim 1 recites as follows (with labels added):
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`1[pre]. A method of constructing a frame structure for data
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`transmission, the method comprising:
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`1[a] generating a first section comprising data configured
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`in a first format compatible with a first communication
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`system using symbols;
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`1[b] generating a second section following the first section,
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`the second section comprising data configured in a second
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`format compatible with a second communication system
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`using symbols, wherein the first communication system’s
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`symbols and the second communication system’s symbols
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`co-exist in one transmission scheme
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`1[c] and wherein: the second format is compatible with
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`the second communication system configured to support
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`higher mobility than the first communication system,
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`wherein each symbol in the second communication system
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`has a shorter symbol period than that in the first communi-
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`cation system;
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`1[d] generating at least one non-data section containing
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`information describing an aspect of data in at least one of
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`the first section and the second section; and
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`1[e] combining the first section, the second section and the
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`at least one non-data section to form the frame structure.
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`Independent claim 8 is identical to claim 1, except that it replaces limitation 1[c]
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`with “and wherein the second communication system has pilot symbols that are
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`denser than those in the first communication system.” Claims 2-4 and 6-7 depend
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`from claim 1 and specify further limitations relating to the nature and location of
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`information within the frame structure. Exhibit 1008 provides a full listing of the
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`challenged claims.
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`D.
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`Priority Date and Prosecution History of the ’096
`Patent
`The application for the ’096 patent was filed on July 7, 2008. It identified two
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`provisional applications filed on July 12, 2007, and September 17, 2007. The July
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`12 provisional, App. No. 60/929,798, consisted of a nine-page slide deck. Ex. 1009.
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`This provisional did not contain any disclosure relating to a second communication
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`system that had a shorter symbol period or denser pilot symbols. Id.; Akl ¶¶ 86-88.
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`Each of the claims challenged in this Petition requires a frame section comprising
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`data configured for a system “wherein each symbol … has a shorter symbol period
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`than that in the first communication system” (claims 1-4, 6-7) or that “has pilot sym-
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`bols that are denser than those in the first communication system” (claim 8). Infra,
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`§ IV(C). Thus, the July 12 provisional did not contain written description support
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`for the challenged claims, and September 17, 2007, is their earliest possible priority
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`date. Petitioner reserves the right to assert a different actual priority date.
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`During prosecution of the application that issued as the ’096 patent, the Ex-
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`aminer issued multiple office actions rejecting the challenged claims over different
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`prior art combinations. The applicants ultimately amended various independent
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`claims to recite that “the first communication system and the second communication
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`system co-exist in one transmission scheme.” Ex. 1010 at 28, 41. The applicants
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`identified the support for this amendment as being “paragraph [0025] of Applicants’
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`published specification” (id. at 41), which disclosed that “the present invention may
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`allow data of an old orthogonal frequency division multiple access (OFDMA) sys-
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`tem (hereinafter a legacy system) and data of a new OFDMA system to co-exist in
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`an OFDMA frame by changing a frame structure of the OFDMA frame” (id. at 5,
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`[0025])3; Akl ¶¶ 89-90.
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`Following this amendment, the applicants held a telephonic interview in
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`which the Examiner s