UNITED STATES PATENT AND TRADEMARK OFFICE
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
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`BLACKBERRY CORP.,
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`Petitioner
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` v.
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`UNILOC 2017 LLC,
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`Patent Owner
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`Patent No. 7,167,487
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`DECLARATION OF R. MICHAEL BUEHRER, Ph.D., FIEEE
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`BLACKBERRY 1002
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`
`TABLE OF CONTENTS
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`I.
`INTRODUCTION .......................................................................................... 1
`BACKGROUND AND QUALIFICATIONS ............................................... 1
`II.
`III. MATERIALS REVIEWED ........................................................................... 7
`IV. LEGAL PRINCIPLES ................................................................................... 8
`A. Anticipation .......................................................................................... 8
`B.
`Obviousness ......................................................................................... 9
`PERSON OF ORDINARY SKILL IN THE ART ....................................... 10
`V.
`VI. TECHNICAL BACKGROUND .................................................................. 12
`A.
`The UMTS Cellular Network Standard ............................................. 12
`B.
`The UMTS Protocol Stack ................................................................. 16
`C.
`Functions of the MAC Layer ............................................................. 22
`D.
`Transport Format Selection in the UE ............................................... 23
`VII. OVERVIEW OF THE ’487 PATENT ......................................................... 30
`VIII. CLAIM CONSTRUCTION ......................................................................... 36
`IX. OVERVIEW OF THE PRIOR ART ............................................................ 37
`A.
`TS 25.321 ........................................................................................... 37
`B.
`R2-010182 .......................................................................................... 42
`C.
`TS 25.302 ........................................................................................... 56
`D.
`Peisa ................................................................................................... 59
`X. OVERVIEW OF CONCLUSIONS FORMED ............................................ 63
`XI. THE PRIOR ART DISCLOSES OR SUGGESTS ALL
`THE FEATURES OF CLAIMS 1-6 AND 11-13 OF
`THE ’487 PATENT .................................................................................... 64
`A.
`Claims 1-6 and 11-13 rendered obvious by the
`combination of TS 25.321, R2-010182 and TS 25.302. .................... 64
`Claims 1, 2 and 11-13 are rendered obvious by
`Peisa and claims 4-6 are rendered obvious by
`the combination of Peisa and TS 25.302. ........................................134
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`B.
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`XII. CONCLUSION ..........................................................................................193
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`ii
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`I.
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`
`I, R. Michael Buehrer, Ph.D., FIEEE, declare as follows:
`
`INTRODUCTION
`
`1.
`
`I have been retained by BlackBerry Corp. (“Petitioner”) as an
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`independent expert consultant in this proceeding before the United States Patent
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`and Trademark Office (“USPTO”) regarding U.S. Patent No. 7,167,487 (“the ’487
`Patent”) (EX-1001).1 I have been asked to consider whether certain references
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`disclose or suggest the features recited in claims 1-6 and 11-13 of the ’487 Patent
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`(“the Challenged Claims”). My opinions are set forth below.
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`2.
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`I am being compensated at a rate of $400/hour for my work in this
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`proceeding.
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`3. My compensation is in no way contingent on my findings, the
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`presentation of my findings in testimony, or the outcome of this proceeding. I
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`have no other interest in this proceeding.
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`II. BACKGROUND AND QUALIFICATIONS
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`4. My academic and professional background is in Electrical and
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`Computer Engineering, and I have been working in those fields since the
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`completion of my Ph.D. over 20 years ago. The details of my background and
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`1 Where appropriate, I refer to exhibits that I understand are to be attached to the
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`petition for Inter Partes Review of the ’487 Patent.
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`1
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`
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`education, and a listing of all publications that I have authored, are provided in my
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`Curriculum Vitae (EX-1003). Below, I provide a short summary of my education
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`and experience that I believe to be most pertinent to the opinions I have formed in
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`this case.
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`5.
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`I received a B.S. in Electrical Engineering from The University of
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`Toledo in 1991, an M.S. in Electrical Engineering from The University of Toledo
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`in 1993, and a Ph.D. in Electrical Engineering from Virginia Polytechnic Institute
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`and State University in 1996. The focus of my graduate work was wireless
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`communication systems. My Ph.D. thesis involved the application of multiuser
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`detection (an advanced signal processing approach to interference mitigation) to
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`CDMA-based cellular systems.
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`6.
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`After completion of my Ph.D. in 1996, I joined Bell Laboratories, the
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`research division of Lucent Technologies, where I worked for five years as a
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`Member of Technical Staff and later as a Distinguished Member of Technical
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`Staff. My work there focused on developing advanced technologies for cellular
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`telecommunications, including for 3G cellular standards. For example, while at
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`Bell Labs, I developed and implemented algorithms for intelligent antenna systems
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`which increased the voice capacity (i.e., number of simultaneous phone calls) and
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`data capacity of cellular systems. These algorithms were included in Lucent
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`2
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`

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`
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`Technologies’ 3G CDMA cellular base station. I also developed techniques
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`known as transmit diversity techniques which increased reliability (i.e., reduced the
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`probability of a dropped call) of cellular systems. These transmit diversity
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`techniques were standardized in the 3GPP2 cellular standard known as cdma2000.
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`7.
`
`I am currently a Professor in the Bradley Department of Electrical and
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`Computer Engineering at Virginia Polytechnic Institute and State University,
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`where I have taught and conducted research in the area of wireless
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`communications for the past 18 years. Specifically, I have taught courses which
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`cover wireless communications and signal processing (including the underlying
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`concepts) at the undergraduate and graduate levels. For example, I teach a
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`sophomore-level course which introduces the concepts of signals and systems, a
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`junior-level course which introduces the basic concepts of communication systems,
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`senior-level and graduate-level courses which cover advanced digital
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`communication topics, and also graduate-level courses which teach the advanced
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`technologies underlying the latest wireless systems, such as Wi-Fi and Fourth
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`Generation (4G) cellular communication standards (such as LTE and LTE-
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`Advanced). I also teach graduate courses on advanced topics such as Information
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`Theory, Spread Spectrum Communications and CDMA.
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`8.
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`I am also the director of Wireless @ Virginia Tech, a comprehensive
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`3
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`research group focusing on wireless communications which consists of 14 faculty
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`members and approximately 85 graduate students. My specific research focuses
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`on advanced wireless communications and geolocation techniques. This research
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`has examined both advanced theoretical concepts as well as the application of
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`these concepts to the latest wireless standards. As an example of the latter, I (along
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`with my students) have conducted research applying multiuser/multi-antenna
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`signal processing to LTE. I have also applied advanced geolocation techniques to
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`LTE systems.
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`9. My research work has been funded by national agencies including the
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`National Science Foundation (NSF), the Defense Advanced Research Projects
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`Agency (DARPA), the Office of Naval Research (ONR), the Army Research Lab,
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`as well as many industrial sponsors.
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`10. During 2009, I was a visiting researcher at the Laboratory for
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`Telecommunication Sciences (LTS) a federal research lab which focuses on
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`telecommunication challenges for national defense. While at LTS, my research
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`focus was in the area of cognitive radio with a particular emphasis on statistical
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`learning techniques.
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`11. As a consultant, I have examined in detail various aspects of the
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`physical layer, MAC layer, RLC, and the signaling of the standards for 2G, 3G,
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`4
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`and 4G cellular systems. I have also specifically studied the standardization
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`process in 3GPP as it relates to the standardization of a particular aspect of 4G
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`(LTE). I have also taught short-courses in the area of cellular and Wi-Fi
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`communications.
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`12.
`
`I have authored and co-authored approximately 250 publications in
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`my area of expertise, which have been published in the leading journals in wireless
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`communications and signal processing, including IEEE Transactions on
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`Communications, IEEE Transactions on Wireless Communications, IEEE
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`Transactions on Information Theory, and IEEE Transactions on Signal Processing,
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`and at all of the major conferences in wireless communications. In 2010, I was co-
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`recipient of the Fred W. Ellersick MILCOM Award for the best paper in the
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`unclassified technical program of the IEEE Military Communications Conference
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`(MILCOM). A complete list of my publications over the last 25 years is included
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`in my Curriculum Vitae.
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`13.
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`14.
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`I also hold 16 issued patents in the area of wireless communications.
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`I currently serve as an editor for IEEE Transactions on Wireless
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`Communications. I also recently served as a guest editor for a special issue of the
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`Proceedings of the IEEE. I was formerly an associate editor for IEEE Wireless
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`Communications Letters, IEEE Transactions on Vehicular Technologies, IEEE
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`5
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`Transactions on Communications, IEEE Transactions on Signal Processing, and
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`IEEE Transactions on Education. I also formerly served as the guest editor for the
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`IEEE Journal on Special Topics in Signal Processing. I served as the Technical
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`Program Chair for the Signal Processing for Communications Symposium at the
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`2017 IEEE International Conference on Communications. Previously, I was the
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`Organizer and Technical Co-Chair for both the 2015 and 2016 IEEE Global
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`Communications Conference Workshop on Localization and Tracking: Indoors,
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`Outdoors and Emerging Networks (LION). I have also served on the technical
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`program committees of several other conferences and workshops in my field.
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`15.
`
`I am a Fellow of the IEEE (so named “for contributions to wideband
`
`signal processing in communications and geolocation”). In 2010, I was awarded
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`the Ellersick Best Paper Award in the Unclassified Technical Program, at the IEEE
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`Military Communications Conference. I received the SDR Forum Best Paper
`
`Award in 2007 and the Outstanding Paper Award at the SDR Forum in 2008. I
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`received the Dean’s Award for Teaching Excellence in April 2014 and the Dean’s
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`Award for Outstanding New Assistant Professor, College of Engineering in 2003.
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`Both awards were given by the College of Engineering at Virginia Tech. While at
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`Bell Laboratories, I was awarded the Bell Labs President’s Silver Award for
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`outstanding research contributions and the 1999 Best Paper Award in the Bell Labs
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`6
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`Technical Journal.
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`III. MATERIALS REVIEWED
`
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`16. The opinions contained in this Declaration are based on the
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`documents I reviewed, my professional judgment, as well as my education,
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`experience, and my general knowledge of wireless communications.
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`17.
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`In forming my opinions expressed in this Declaration, I reviewed
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`the following materials:
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`EX-1001 U.S. Patent No. 7,167,487 (“the ’487 Patent”)
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`EX-1004
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`Prosecution History of U.S. Patent No. 7,167,487 (“the
`Prosecution History”)
`
`EX-1007
`
`3GPP TS 25.321 V3.6.0 (2000-12) Technical Specification, “3rd
`Generation Partnership Project; Technical Specification Group
`Radio Access Network; MAC protocol specification (Release
`1999)” (“TS 25.321”)
`EX-1008 Mitsubishi Electric Telecom (Trium R&D), R2-010182 “Corrections
`to logical channel priorities in MAC protocol,” Change Request for
`3GPP TS 25.321 V3.6.0, 3GPP TSG-WG2 Meeting #18, Edinburgh,
`Scotland, 17th -19th January 2001(“R2-010182”)
`
`EX-1009
`
`3GPP TS 25.302 V3.6.0 (2000-09) Technical Specification, “3rd
`Generation Partnership Project; Technical Specification Group
`Radio Access Network; Services provided by the physical layer
`(Release 1999)” (“TS 25.302”)
`
`EX-1013 U.S. Patent No. 6,850,540 (“Peisa”)
`EX-1015 Holma and Toskala, “WCDMA for UMTS”, Wiley, 2000
`(excerpts) (“Holma”)
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`
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`7
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`EX-1016
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`
`F. Muratore, “UMTS: Mobile Communications for the
`Future”, Wiley, 2001 (excerpts) (“Muratore”)
`
`EX-1017 K. Washburn and J. Evans, “TCP/IP: Running a successful
`network”, Addison-Wesley, 1996 (“Washburn”)
`
`
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`18. All of the opinions contained in this declaration are based on the
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`documents I reviewed and my knowledge and professional judgment. My opinions
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`have also been guided by my appreciation of how a person of ordinary skill in the
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`art would have understood the claims and the specification of the ’487 Patent at the
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`time of the alleged invention, which I have been asked to initially consider was as
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`early as May 21, 2001, the filing date of the foreign priority application DE
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`10124940 (“the ’940 application”). I have been asked to assume that the ’487
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`Patent properly claims the benefit of the ’940 application. My opinions reflect
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`how one of ordinary skill in the art would have understood the ’487 Patent, the
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`prior art to the patent, and the state of the art at the time of the alleged invention.
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`19. Based on my experience and expertise, it is my opinion that certain
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`references disclose or suggest all the features recited in the Challenged Claims of
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`the ’487 Patent, as I discuss in detail below.
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`IV. LEGAL PRINCIPLES
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`A. Anticipation
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`20.
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`I have been informed that a patent claim is invalid as anticipated
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`under 35 U.S.C. § 102 if each and every element of a claim, as properly construed,
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`is found either explicitly or inherently in a single prior art reference. Under the
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`principles of inherency, if the prior art necessarily functions in accordance with, or
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`includes the claimed limitations, it anticipates.
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`21.
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`I have been informed that a claim is invalid under 35 U.S.C. § 102(a)
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`if the claimed invention was known or used by others in the U.S., or was patented
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`or published anywhere, before the applicant’s invention. I further have been
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`informed that a claim is invalid under 35 U.S.C. § 102(b) if the invention was
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`patented or published anywhere, or was in public use, on sale, or offered for sale in
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`this country, more than one year prior to the filing date of the patent application.
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`And a claim is invalid, as I have been informed, under 35 U.S.C. § 102(e), if an
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`invention described by that claim was described in a U.S. patent granted on an
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`application for a patent by another that was filed in the U.S. before the date of
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`invention for such a claim.
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`
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`B. Obviousness
`22.
`I have been informed that a patent claim is invalid as “obvious” under
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`35 U.S.C. § 103 in light of one or more prior art references if it would have been
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`obvious to a person of ordinary skill in the art at the time of the invention of the
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`’487 patent (“POSITA”—which I discuss in more detail below), taking into
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`account: (1) the scope and content of the prior art, (2) the differences between the
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`prior art and the claims, (3) the level of ordinary skill in the art, and (4) any so
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`called “secondary considerations” of non-obviousness, which include: (i) “long felt
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`need” for the claimed invention, (ii) commercial success attributable to the claimed
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`invention, (iii) unexpected results of the claimed invention, and (iv) “copying” of
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`the claimed invention by others.
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`23.
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`I have been informed that a claim can be obvious in light of a single
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`prior art reference or multiple prior art references. To be obvious in light of a
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`single prior art reference or multiple prior art references, a reason to modify the
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`single prior art reference, or combine two or more references, in order to achieve
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`the claimed invention can be provided. This reason may come from a teaching,
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`suggestion, or motivation to combine, or may come from the reference or
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`references themselves, the knowledge or “common sense” of one skilled in the
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`art, or from the nature of the problem to be solved, and may be explicit or implicit
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`from the prior art as a whole. I have been informed that the combination of
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`familiar elements according to known methods is likely to be obvious when it
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`does no more than yield predictable results. I also understand it is improper to
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`rely on hindsight in making the obviousness determination.
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`V.
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`PERSON OF ORDINARY SKILL IN THE ART
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`24.
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`I was asked to provide my opinion on the level of a person of ordinary
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`skill in the art with respect to the ’487 Patent at the time of its alleged invention (as
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`early as May 21, 2001, the priority date of the ’487 Patent) (“POSITA”). I
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`understand that a POSITA is a hypothetical person who is presumed to know the
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`relevant prior art and that this is not the same as the actual inventor’s skill. I
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`further understand the factors that may be considered in determining the level of
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`skill include: the types of problems encountered in the art, prior art solutions to
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`those problems; rapidity with which innovations are made; sophistication of the
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`technology; and educational level of active workers in the field. I understand that
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`not all such factors may be present in every case, and one or more of them may be
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`more important than others.
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`25.
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`I have reviewed the ’487 Patent and I am familiar with the patent’s
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`subject matter, which is within the scope of my education and professional
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`experience. Based at least on my background including over 20 years of studying,
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`researching and teaching engineering, I am familiar with the issues and technology
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`relating to this patent. Based on my understanding of the art, prior solutions to
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`problems in the art, the rapidity with which innovations were made, the
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`sophistication of the technology, and the educational level of active workers in the
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`field, I believe that a POSITA would have had at least a Master of Science Degree
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`in an academic area emphasizing telecommunications systems, or an equivalent
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`field (or a similar technical Master’s Degree, or higher degree) with a
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`concentration in telecommunications systems. Alternatively, a POSITA would
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`have had a Bachelor’s Degree (or higher degree) in an academic area emphasizing
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`telecommunications systems with two or more years of work experience in
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`telecommunications systems.
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`26. All of my opinions in this declaration are from the perspective of a
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`POSITA, as I have defined it here, during the relevant timeframe, i.e., as early as
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`May 21, 2001.
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`VI. TECHNICAL BACKGROUND
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`27. The ’487 Patent relates to wireless networks in general, and cellular
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`networks in particular. Thus, in this section, I present a brief overview of cellular
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`wireless networks. More specifically, I provide an overview of cellular networks
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`based on the 3rd Generation Partnership Project (“3GPP”) Universal Mobile
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`Telecommunications System (“UMTS”) Third Generation (“3G”) standard.
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`
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`A. The UMTS Cellular Network Standard
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`28.
`
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`3GPP is a standardization project developed by the standardization
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`bodies from Europe, Japan, Korea and the United States. UMTS is the 3G cellular
`standard2 produced by that body, and is based on wideband CDMA. Third
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`2 First Generation (1G) cellular standards were the original standards based on
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`generation cellular networks for mobile communications rely on either the UMTS
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`standard or another standard known as cdma2000. In general, 2G networks that
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`were based on US TDMA or GSM standards evolved to UTMS in the early 2000’s,
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`while those based on the IS-95 (also known as cdmaOne) standard evolved to
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`cdma2000 during that same time period. The basic architecture of the UMTS
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`network is shown below, taken from Figure 5.2 of Holma, page 54. The figure
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`shows that the UMTS network includes a UE, an UTRAN, and a CN, which is
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`connected to external networks. The UE (user equipment) is a term used by the
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`standards, referring to the mobile entity (ME) (e.g., mobile device) used by the
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`subscriber to connect to the cellular network via a radio interface. The UE is also
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`analog modulation such as the Advanced Mobile Phone System (AMPS). The first
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`AMPS network was deployed in the early 80’s and 1G cellular grew steadily
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`through the decade. The Second Generation standards were digital standards such
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`as IS-54 (US TDMA) and IS-95 in the US and GSM in Europe and were lunched
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`in the early 90’s. Third generation standards were generally CDMA systems and
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`include UTMS and edma2000. These systems were developed in the 90’s and
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`launched in the early 2000’s. The latter part of that decade saw the development of
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`Fourth Generation (4G) cellular commonly known at LTE. LTE saw widespread
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`deployment around 2010.
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`known as a radio terminal, and it further includes the UMTS Subscriber Identity
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`Module (USIM) card (Holma, page 55). A POSITA would have known that
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`examples of the UE included a cellular or mobile phone (or possibly other devices
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`such as a portable laptop computer with cellular connectivity) used by the
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`subscriber.
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`29. The UTRAN (UMTS Terrestrial Radio Access Network) handles all
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`
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`radio-related functionality and connects the UE to the CN (core network) through
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`the Iu interface. As shown in the figure 1 schematic below, the UTRAN acts as an
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`access network which connects UEs to the core network of the UMTS system. The
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`UEs are connected through the core network to each other, or to other external
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`networks outside the UMTS network, such as the Internet and landline phone
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`networks (e.g., PSTN, ISDN, etc.).
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`30. The UTRAN has two main parts as shown in the figure below, the
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`Node B and the Radio Network Controller (RNC). The term ‘Node B’ is a 3GPP-
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`specific term that refers to the radio device that communicates with the UE (via the
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`radio interface known as the Uu interface), and with the Radio Network Controller
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`(via the Iub interface). The more generic term for the Node B is ‘base station’.
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`Formally, it converts the data between the Uu and Iub interfaces and plays a role in
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`radio resource control (RRC) (Holma, page 55). Its primary role is to serve as the
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`air interface between the UE and the network in each cell of the network.
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`Figure 1: Schematic of UTRAN Architecture
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`31. The network element which controls the Node B is the RNC. Each
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`
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`RNC is associated with a service area that includes several cells, with each cell
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`served by a Node B. The RNC controls multiple Node Bs in the various cells
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`within its service area. The RNC controls all services provided to the CN, and in
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`particular manages the connections between the UE and the CN.
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`32. The CN contains several elements, including the Mobile Services
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`Switching Center (MSC), Visitor Location Register (VLR), the Home Location
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`Register (HLR), the Gateway MSC (GMSC), the Serving GPRS (General Packet
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`Radio Service) Support Node (SGSN) and the Gateway GPRS Support Node
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`(GGSN). The HLR and VLR are databases that store user profiles detailing the
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`services, roaming areas, and other aspects of the users’ subscriptions for network
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`subscribers and “visiting” UEs respectively. The MSC switches circuit switched
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`(CS) services (e.g., voice in 3G networks) while the GMSC connects the network
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`to outside phone networks (e.g., the PSTN). The SGSN and GGSN connect packet
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`switched services to outside networks (e.g., the Internet).
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`
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`B.
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`The UMTS Protocol Stack
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`33. The radio interface is the air interface, i.e. the wireless
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`communications medium, between the UE and the UTRAN. The radio interface
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`protocol structure is shown in the figure (Holma, Fig. 7.1) below and contains two
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`main sets of functionality: the user plane (for transferring user data) and the control
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`plane (for transferring network signaling/control data). (Holma., Pg. 122). The
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`physical (“PHY”) layer is the lowest layer in the connection between the UE and
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`the Node B and is also termed Layer 1 (“L1”). It provides services to the layer
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`16
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`immediately above it in the UMTS protocol stack, namely, the Medium Access
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
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`U.S. Patent No. 7,167,487
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`Control (MAC) layer, using transport channels (Holma, page 122, see also
`
`Muratore, § 4.4.1). The MAC layer in turn provides services to the layer
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`immediately above it in the UMTS protocol stack, namely, Radio Link Control
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`(RLC) layer, using logical channels. The MAC and RLC layers are sublayers in
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`the Data Link Layer, which is also referred to as Layer 2 (“L2”) (Muratore, §
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`4.4.1). The Packet Data Convergence Protocol (PDCP) and Broadcast/Multicast
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`Control (BMC) protocol are also part of L2 and primarily handle header
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`compression and broadcast messages respectively.
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`34. Transport channels are used to transfer information from the MAC
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`layer to the PHY layer and vice versa, whereas logical channels are used to transfer
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`17
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`information from the RLC layer to the MAC layer and vice versa. Data packets
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
`
`U.S. Patent No. 7,167,487
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`from the logical channels are mapped onto a transport channel. Up to 15 logical
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`channels can be mapped to a single transport channel (Holma, pg. 127). An
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`example mapping between Logical Channels and Transport Channels (from the
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`perspective of the terminal (UE)) is shown below in Figure 4.7 of Muratore
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`(Muratore, pg. 94).
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`
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`
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`35. Logical channels are distinguished based on the information
`
`
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`transferred (Muratore, page 93). There are two primary types of logical
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`channels: control channels (for sending signaling information) and traffic
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`channels (for sending user data). Control channels include the Broadcast Control
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`Channel (BCCH), the Paging Control Channel (PCCH), the Common Control
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`Channel (CCCH), and the Dedicated Control Channel (DCCH). The primary
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`traffic channels include the Dedicated Traffic Channel (DTCH).
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`18
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`Declaration of R. Michael Buehrer, Ph.D., FIEEE
`
`U.S. Patent No. 7,167,487
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`
`36. Transport channels are defined on the basis of the type of information
`
`they transfer and how it is transferred on the radio interface (Muratore, page 56).
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`There are two main classes of transport channels: common channels (where
`
`information is transferred to all mobile terminals without distinction) and dedicated
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`channels (where communication is meant for a specific mobile terminal). The
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`Dedicated Channel (DCH) is the only dedicated channel, while the common
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`channels include the Broadcast Channel (BCH), the Forward Access Channel
`
`(FACH), the Paging Channel (PCH), the Random Access Channel (RACH), the
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`Uplink Common Packet Channel (CPCH), and the Downlink Shared Channel
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`(DSCH) (Holma, page 76-77).
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`19
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`37.
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`I explain the mapping between the logical channels and the transport
`
`
`
`channels using a simple example illustrated in the figure 7.4 of Holma, above
`
`(Holma, pg. 127). In this example, a packet arrives on an instantiation of a DCCH
`
`(a logical channel) at the network side and it is processed by the MAC-d (the MAC
`
`layer entity responsible for dedicated channels). The MAC-d first selects the
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`transport channel to which the logical channel will be mapped. In this case, the
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`logical channel is mapped to the forward access channel (FACH). The next step is
`
`to add a C/T field which indicates the logical channel instance where the packet
`
`originates. This field is 4 bits long allowing up to 15 simultaneous logical
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`20
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`channels using the same transport channel. This is a requirement for common
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`transport channels (which the FACH is) and is optional for dedicated transport
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`channels (only being needed if multiple logical channel instances are mapped to
`
`the same dedicated transport channel). The next step for logical channels being
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`mapped to common transport channels is to set the priority for scheduling followed
`
`by transmission to the MAC-c/sh entity.
`
`38. The first processing step done by the MAC-c/sh entity is to add bits
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`for the UE identification type, the UE id (C-RNTI or U-RNTI) and the Target
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`Channel Type Field (this is needed to separate different types of logical channels
`
`on the same transport channel). The final step is scheduling and priority handling
`
`where the MAC decides when it will transfer the MAC PDU (which is also known
`
`as a Transport Block) on the appropriate transport channel and the Transport
`
`Format Combination it will use. This last step is described in more detail in the
`
`next section.
`
`39. PDU (Protocol Data Unit or Packet Data Unit) is a common term used
`
`to represent a packet of data passed between adjacent layers in the protocol stack
`
`(e.g., see Washburn, page. 457). The RLC provides RLC-PDUs, which are packets
`
`of data from the RLC of a particular size, to the MAC. These PDUs are sized such
`
`that they fit into transport blocks sent on the transport channels. Thus, the
`
`fundamental data block sent form the RLC to the MAC is the PDU (TS 25.321,
`
`
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`21
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`page 10).
`
`40. The control of these aforementioned layers is handled by the Radio
`
`Resource Control (RRC) layer, which is in the control plane as shown in Figure
`
`7.1 of Holma above. RRC messages account for the majority of the control
`
`signaling between the UE and the UTRAN (Holma, page 135). More
`
`specifically, the RRC provides the following functions: (1) functions associated
`
`with mobility in an RRC connection (e.g., hand-over, cell selection, etc.),
`
`Quality of Service (QoS) control, and control of measurements performed by the
`
`mobile (Muratore, page 88-89).
`
`
`
`C.
`
`Functions of the MAC Layer
`
`41. The MAC layer (which is a part of Layer 2, as noted above in § VI.B)
`
`schedules packet transmissions of various data flows (a flow of user data or
`
`signaling data with similar QoS requirements) and must meet certain restrictions
`
`such as only including allowed Transport Format Combinations (TFC) from a
`
`Transport Format Combination Set (TFCS). I define these terms below.
`
`42. The functions of MAC include (TS 25.321, page 17):
`
`• Mapping betw