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`UNITED STATES PATENT AND TRADEMARK OFFICE
`
`
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`
`
`APPLE INC.,
`HTC CORPORATION AND HTC AMERICA, INC.,
`ZTE (USA) INC.,
`Petitioners
`v.
`
`INVT SPE LLC,
`Patent Owner
`
`
`Case No. IPR2018-01473
`U.S. Patent No. 6,611,676
`
`DECLARATION OF BRANIMIR VOJCIC
`
`
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`IPR2018-01473
`Apple v. INVT
`INVT Exhibit 2002 - Page 1
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`
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`IPR2018-01473
`Patent 6,611,676
`
`I, BRANIMIR VOJCIC, hereby declare as follows:
`
`1.
`
`I am competent to testify, and if called upon during an Inter Partes Review
`
`(IPR) proceeding would do so. If called upon as a witness, I could competently
`
`testify to the truth of each statement herein.
`
`2.
`
`I was asked to provide an opinion on Ground 1 asserted in IPR2018-01473,
`
`regarding U.S. Patent No. 6,611,676 (’676 patent) (Ex. 1001), statements made in
`
`the Petition related to Ground 1, and exhibits in support of the Petition’s Ground 1.
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`3. My opinion is based upon my knowledge and experience, and my review of
`
`the ’676 patent, the Petition, and exhibits in support of the Petition.
`
`BACKGROUND
`I.
`I am an expert in wireless technology and other areas of
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`4.
`
`telecommunications, signal processing, and electrical engineering. I am presently a
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`Professor Emeritus of Engineering and Applied Science at The George
`
`Washington University. I retired from the university in May 2015, where I was a
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`member of the faculty since September 1, 1991. In addition, I have served as a
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`consultant for a number of companies in the wireless communications industry in
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`various technology areas. I have also served on numerous committees and as a
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`reviewer and editor for several journals, conferences, and organizations.
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`5.
`
`I am presently President of Xplore Wireless, LLC, a small
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`telecommunication consulting company. I am also a co-founder, Director, CEO
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`
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`Apple v. INVT
`INVT Exhibit 2002 - Page 2
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`IPR2018-01473
`Patent 6,611,676
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`and CTO of LN2, a startup in the telecommunication space.
`
`6.
`
`I received my Diploma of Engineering, Master of Science, and Doctor of
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`Science degrees in Electrical Engineering from the University of Belgrade in
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`Yugoslavia in 1981, 1986, and 1989, respectively. The primary focus of my Doctor
`
`of Science studies was on Code Division Multiple Access (CDMA) and spread
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`spectrum communications technologies.
`
`7.
`
`In 1991, I joined The George Washington University as an Assistant
`
`Professor and was promoted to Associate Professor and Professor in 1997 and
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`2000, respectively. From 2001 to 2004, I served as the Chairman of the Electrical
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`and Computer Engineering Department at The George Washington University.
`
`During my tenure at The George Washington University, until May 2015, I taught
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`many different courses on communications theory and networks, wireless
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`communications, CDMA, and I was a course director for a number of courses in
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`communications. I have supervised students mostly in the areas of communications
`
`and coding theory, wireless communications/networks , CDMA (including IS-95,
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`CDMA2000, WCDMA/HSDPA/HSUPA) and OFDM/LTE and have been a thesis
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`director for a number of Doctor of Science candidates, who now have successful
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`careers in academia, industry, and government.
`
`8. My research in the areas I just mentioned has been supported by the
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`communications industry and various Government agencies, such as Advanced
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`IPR2018-01473
`Apple v. INVT
`INVT Exhibit 2002 - Page 3
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`
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`IPR2018-01473
`Patent 6,611,676
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`Research Project Agency (ARPA), National Science Foundation (NSF), and
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`National Security Agency (NSA). Much of this research concerns communications
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`theory, performance evaluation, modeling wireless networks, multi-user detection,
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`adaptive antenna arrays, and ad-hoc networks.
`
`9.
`
`I have authored or co-authored numerous journal and conference papers,
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`contributed to various books, and co-authored a text book on CDMA, entitled “The
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`cdma2000 System for Mobile Communications,” Prentice Hall, 2004. I also served
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`as a co-editor of a book on wireless communications, entitled “Multiaccess,
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`Mobility and Teletraffic in Wireless Communications, Volume III,” Kluwer
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`Academic Publishers, Norwell, Massachusetts, 1998. My CV includes a detailed
`
`listing of my publications.
`
`10.
`
`I have also received awards for my work. In 1995, I received the prestigious
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`National Science Foundation Faculty Early CAREER Development Award. The
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`award is given annually by NSF to a select group of young professors nationwide
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`to promote excellence in teaching and research.
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`11.
`
`I have served as a consultant for numerous companies in the wireless
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`communications industry in technology areas, in the areas of 2G/3G/4G mobile
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`technologies, Wireless LANs, new generation broadcast systems, advanced mobile
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`satellite systems and other aspects of modern communication systems. I have also
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`taught academic courses as well as short courses for the industry and government
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`
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`3
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`IPR2018-01473
`Apple v. INVT
`INVT Exhibit 2002 - Page 4
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`
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`IPR2018-01473
`Patent 6,611,676
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`on various aspects of communications in the areas of 2G, 2.5G, 3G and 4G cellular
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`standards, such as CDMA2000 1xRTT, CDMA2000 Evolution Data Optimized
`
`(EVDO), Wideband Code Division Multiple Access (WCDMA) and LTE.
`
`12.
`
`I am a Senior Member of the IEEE and was an Associate Editor for IEEE
`
`Communications Letters and Journal on Communications and Networks. I served
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`as a member of technical program committees, as a session organizer for many
`
`technical conferences and workshops, and as a reviewer of technical papers for
`
`many journals and conferences.
`
`13.
`
`I am a co-inventor of U.S. Patent No. 6,523,147, entitled “Method and
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`Apparatus for Forward Error Correction Coding for an AM In-Band On-Channel
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`Digital Audio Broadcasting System,” US Patent No. 8,595,590 B1, entitled
`
`“Systems and Methods for Encoding and Decoding Check-Irregular Non-
`
`Systematic IRA Codes,” and applications, “Joint Source-Channel Decoding with
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`Source Sequence Augmentation”, US 20140153654 A1, Jun 5, 2014, “Systems and
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`Methods for Advanced Iterative Decoding and Channel Estimation of
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`Concatenated Coding Systems”, US 20140153625 A1, Jun 5, 2014, “Advanced
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`Decoding of High/Medium/Low Density Parity Check Codes”, PCT/US13/72883,
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`and International Application Number PCT/CA01/01488, entitled “Multi-User
`
`Detector For Direct Sequence - Code Division Multiple Access (DS/CDMA)
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`Channels.”
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`IPR2018-01473
`Apple v. INVT
`INVT Exhibit 2002 - Page 5
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`IPR2018-01473
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`14. A copy of my curriculum vitae is attached as Exhibit 2003.
`
`PERSON SKILLED IN THE ART
`II.
`I have reviewed the ’676 patent, the Petition, the Singer Declaration (Ex.
`
`15.
`
`1003), the Keskitalo reference (Ex. 1004), and the Lindell reference (Ex. 1005).
`
`16. The invention in the ’676 patent relates to CDMA mobile stations and
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`CDMA transmission methods used for cellular radio communication systems.
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`17. As such, I believe that a person skilled in the art of the technology described
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`in the ’676 patent would have at least a bachelor’s degree in Electrical
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`Engineering, or equivalent, with three years of experience researching or working
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`with cellular radio communication systems, or a master’s degree in Electrical
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`Engineering, or equivalent, with one year of experience researching or working
`
`with cellular radio communication systems.
`
`18.
`
`I believe that I am a person skilled in the art of the technology described in
`
`the ’676 patent.
`
`LEGAL PRINCIPLES
`III.
`I have been informed that expert opinion testimony is generally permitted
`19.
`
`where the expert’s scientific, technical, or other specialized knowledge will help
`
`the trier of fact to understand the evidence or to determine a fact in issue. The
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`expert witness must be qualified as an expert by knowledge, skill, experience,
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`training, or education to testify in the form of an opinion.
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`IPR2018-01473
`Apple v. INVT
`INVT Exhibit 2002 - Page 6
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`IPR2018-01473
`Patent 6,611,676
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`20.
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`I understand that there is no requirement of a perfect match between the
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`expert’s experience and the relevant field. A person may not need to be a person of
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`ordinary skill in the art in order to testify as an expert, but rather must be “qualified
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`in the pertinent art.” For example, the absence of an advanced degree in a
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`particular field may not preclude an expert from providing testimony that is helpful
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`to the Board, so long as the expert’s experience provides sufficient qualification in
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`the pertinent art.
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`21.
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`I also understand that expert testimony may have many uses. For example, it
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`may be used to explain the relevant technology to the panel. It may also be used to
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`establish the level of skill in the art and describe the person of ordinary skill in the
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`art. Experts may testify about the teachings of the prior art and how they relate to
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`the patentability of the challenged claims. Expert testimony may also be offered on
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`the issue of whether there would have been a reason to combine the teachings of
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`references in a certain way, or if there may have been a reasonable expectation of
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`success in doing so.
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`BACKGROUND OF THE INVENTION
`IV.
`22. As explained by the ’676 patent, traditionally, the base station responded to
`
`interference by regulating transmission power. Ex. 2001 at 1:41-45. The base
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`station regulated transmission power based on two variables: “reception” signal-to-
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`interference ratio (SIR) and “target” SIR. Ex. 1001 at 1:41-46. SIR is the quotient
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`6
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`IPR2018-01473
`Apple v. INVT
`INVT Exhibit 2002 - Page 7
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`IPR2018-01473
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`between the average received signal power and the average received interference
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`(co-channel and/or from adjacent channels) power, i.e. cross-talk, from other
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`transmitters and/or channels than the useful signal. When the reception SIR was
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`less than the target SIR, the UE sent a command to the base station to increase
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`transmission power. When the reception SIR is greater than the target SIR, the UE
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`sent a command to the base station to decrease transmission power. Id. at 1:26-32.
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`23. An increase in transmission power is “likely to increase interference with
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`other mobile stations to an intolerable degree.” Ex 1001 at 1:50-55. As a result, all
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`mobile stations in a similar geographic area will experience decreased
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`performance.
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`24. The reception SIR is a function of reception quality and the change in
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`transmission power, as measured by the UE. Id. at 1:23-26; 1:41-45. The received
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`SIR generally changes due to signal fading. Id. at 1:47-49. It may also change due
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`to the changes in propagation environment, e.g. sudden signal blockages due to
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`obstructions, or changes in interference activity.
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`25. The target SIR is generally a function of the required quality, e.g. frame
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`error rate (FER), mobile station’s transmission rate, and environment. Id. at 1:33-
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`40 and 1:46-48. Id. at 1:46-49. Sometimes the target SIR may be also influenced
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`by the type and priority of data being transmitted and other factors. Similar to
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`reception SIR, the target SIR sometimes increases due to factors other than the
`
`
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`7
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`IPR2018-01473
`Apple v. INVT
`INVT Exhibit 2002 - Page 8
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`IPR2018-01473
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`FER, such as the transmission rate. The diagram below demonstrates this this
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`iterative process of the traditional approach:
`
`
`
`
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`There are several benefits of the approach claimed by the ’676 patent, as
`
`compared to the prior art.
`
`First, reducing the transmission rate without changing the transmission
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`power allows for the optimal or fastest transmission as long as the inference with
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`others is within the allowable range set by the base station. Id. at 11:53-55. Thus,
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`IPR2018-01473
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`the invention makes it possible to improve the reception quality of a UE even if the
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`condition of the communication path deteriorates drastically and not increase the
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`level of interference with others. Id. at 7:16-25. Second, the use of the TPC
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`signal—information already reported by the UE—for channel estimation reduces
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`the need for additional control information. Id. at 10:37-41.
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`26. Thus, the ’676 patent provides improved overall system capacity that
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`enables each UE to transmit successfully at data rates that could not be achieved
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`without the invention, while still staying below a max transmission rate set by the
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`base station.
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`V.
`
`A RATE CHANGE CIRCUITRY IS NOT INTENDED FOR
`CUTTING OFF TRANSMISSION POWER
`27. A person skilled in the art would understand that the rate change circuitry of
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`the ’676 patent is not intended for cutting off transmission power. i.e.
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`discontinuing transmission completely. The ’676 patent allows a radio
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`communication system to achieve better data transmission quality by controlling
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`the transmission rate. Ex. 1001 at 1:59-67. Cutting off transmission power has the
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`opposite effect of achieving better transmission: reducing transmission power to
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`zero means no data transmission, and no data transmission means a disruption in
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`radio communication and synchronization. Reducing transmission power to zero
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`also interrupts the rate control feedback loop described in the ’676 patent, which is
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`IPR2018-01473
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`necessary for the comparison circuitry to compare the transmission power values.
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`See, e.g., Ex.1001 at Fig. 12.
`
`VI.
`
`A POSITA WOULD NOT COMBINE KESKITALO AND
`LINDELL
`28. The ’676 patent and Keskitalo address the reduction of interference. There is
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`no motivation to combine Lindell and Keskitalo are they are simply not
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`compatible, even if combined, for multiple reasons.
`
`29. First, Lindell is directed to specific absorption ratio (SAR) related power
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`measurements, to prevent a long term average radio frequency (RF) power
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`radiation to a human body/head to exceed a regulated maximum level, and not to
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`rate control and closed loop power control (closed Loop Power Control refers to
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`the CDMA power control method where feedback is used for adjusting the
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`transmit power level). Ex. 1005 at 2:1-4. Lindell is concerned with adjusting power
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`up and down to maintain signal transmission quality level, such as signal-to-noise
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`ratio, or match required power with the transmission rate. A POSITA would not
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`look at Lindell to cure the deficiencies of Keskitalo.
`
`30. Second, Keskitalo deals only with rate control and mentions closed loop
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`power control only in passing without going into details of power control or its
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`possible connection with rate control, except mentioning that signal-to-noise ratio
`
`is the metric used for power control adjustments. Keskitalo at 3:9-19. Thus
`
`
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`10
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`IPR2018-01473
`Apple v. INVT
`INVT Exhibit 2002 - Page 11
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`
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`IPR2018-01473
`Patent 6,611,676
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`Keskitalo does not provide motivation/suggestion to improve power control in
`
`order to bring other references (such as Lindell). Moreover, a POSITA would find
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`that power adjustment algorithms in Keskitalo and Linder are not compatible. The
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`former is doing short term adjustments of power, up and down, to maintain a
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`desired signal-to-noise ratio measured at the baseband, while the latter is
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`preventing a very long term average RF power level to exceed some predetermined
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`maximum. These approaches deal with completely different issues and
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`correspondingly require completely difference solutions.
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`31. Third, Keskitalo’s CDMA cellular system was discussed in the context of
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`CDMA systems being tested at the time—around 1993. Specifically, Keskitalo
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`references a CDMA system with a bandwidth of 1.25 MHz and the spreading code
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`rate of 1.2288 Mbit/s. Ex. 1004 at 1:33-35; 4:26-28. A POSITA would understand
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`that this CDMA system corresponds to the IS-95 CDMA system that was being
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`tested around 1993 and proposed for adoption as a 2G CDMA system. In the IS-95
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`CDMA system, power control bits are sent at the rate of 800 bits/s, i.e., one power
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`control bit every 1.25 ms to adjust transmit power. Further, Keskitalo cited
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`WO9419876, which incorporates by reference U.S. Patent No. 5,056,109. Ex.
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`2003; Ex. 2004. In U.S. Patent No. 5,056,109, the power control commands are
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`sent at the rate of 1,000 command per second. Ex. 2004 at 16:46-48. This further
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`implies that the received and transmit power measurements are performed on that
`
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`11
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`INVT Exhibit 2002 - Page 12
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`IPR2018-01473
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`scale to follow rapid channelvariations.
`
`32.
`
`On the other hand, the power measurement system for SARin Lindell
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`operates on scales of many minutes(“‘e.g. 6 min or 30 min”). Thus, the circuitry for
`
`power measurementon suchalongscale is useless in the contextof the ’676 patent
`
`and Keskitalo (i.e. incompatible with Keskitalo) where powervariations are on the
`
`scale of ms, i.e., more than 5 orders of magnitudeshorter than in Lindell. Because
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`of this, a POSITA would not be motivated to look at Lindell to resolve deficiencies
`
`in Keskitalo.
`
`33.
`
`In view of the above, a POSITA would recognize that Keskitalo and Lindell
`
`would not be compatible.
`
`I declare under penalty of perjury under the laws of the United States of America
`
`that the foregoingis true and correct.
`
`January 2, 2019
`
`Pv ot171112;'
`
`Branimir Vojcic
`
`‘Ce
`
`12
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`IPR2018-01473
`Applev. INVT
`INVT Exhibit 2002 - Page 13
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`IPR2018-01473
`Apple v. INVT
`INVT Exhibit 2002 - Page 13
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