UNITED STATES PATENT AND TRADEMARK OFFICE
`
`
`
`
`
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
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`
`
`
`
`
`ERICSSON, INC. &
`TELEFONAKTIEBOLAGET LM ERICSSON
`Petitioners
`
`v.
`
`INTELLECTUAL VENTURES II LLC
`Patent Owner
`____________________
`
`Case IPR2014-01185
`U.S. Patent No. 7,269,127
`____________________
`
`DECLARATION OF DIRK HARTOGS, PH.D.
`
`
`
`
`
`Exhibit 2009
`IPR2014-01185
`
`

`

`Table of Contents
`I. 
`Introduction ..................................................................................................... 1 
`Qualifications .................................................................................................. 1 
`II. 
`III.  Materials Considered ...................................................................................... 4 
`IV.  Applicable Legal Standards. ........................................................................... 5 
`A.  My Understanding of Obviousness. ...................................................... 5 
`B.  My Understanding of Claim Construction. ........................................... 6 
`Level of Ordinary Skill in the Art. ................................................................. 7 
`V. 
`VI.  Overview of the Technology. ......................................................................... 7 
`A.  Orthogonal Frequency Division Multiplexing (OFDM) ....................... 7 
`B. 
`Training Symbols .................................................................................. 8 
`C. 
`The ’127 Patent ................................................................................... 10 
`1. 
`The encoder element ................................................................ 11 
`2. 
`The modulator element ............................................................ 12 
`3. 
`A frame structure embodiment from the ’127 patent .............. 12 
`VII.  Understanding of Certain Terms .................................................................. 15 
`A. 
`“pilot symbol” ..................................................................................... 15 
`1. 
`A “pilot symbol” is a frequency domain symbol. .................... 16 
`2. 
`A “pilot symbol” refines “the calibration of a receiver
`to a transmitter.” ....................................................................... 20 
`Petitioners’ proposed construction is not the broadest
`reasonable interpretation. ......................................................... 22 
`VIII.  The combination of Schmidl and Arslan / Claims 1–3 and 5 ...................... 24 
`A. 
`Claims 1–3 and 5 ................................................................................. 24 
`IX.  The combination of Schmidl, Arslan, and Kim / Claims 4 and 6–10 .......... 28 
`A. 
`Claims 4 and 6–10 ............................................................................... 28 
`The combination of Schmidl, Arslan, Kim, and Heiskala / Claim 17 .......... 28 
`A. 
`Claim 17 .............................................................................................. 28 
`XI.  Conclusion .................................................................................................... 35 
`
`
`X. 
`
`3. 
`
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`I.
`
`
`
`Introduction
`
`I, Dr. Dirk Hartogs, declare as follows:
`
`1.
`
`I understand that in response to a Petition submitted by Ericsson, Inc.
`
`and Telefonaktiebolaget LM Ericsson (“Petitioners”), an inter partes review of
`
`claims 1–10 and 17 of U.S. Patent No. 7,269,127 (Ex. 1001, “the ’127 patent”) was
`
`instituted by the Patent Trial and Appeal Board (“Board”) on January 28, 2015.
`
`2.
`
`I have been retained on behalf of Patent Owner Intellectual Ventures
`
`II LLC (“Patent Owner”) to provide expert opinions in connection with this inter
`
`partes review. Specifically, I have been asked to provide my opinion relating to an
`
`inquiry into the patentability of claims 1–10 and 17 of the ’127 patent relative to
`
`various combinations of Schmidl, Arslan, Kim, and Heiskala.
`
`II. Qualifications
`
`3.
`
`I have been involved in communications technologies, including cel-
`
`lular, 802.11, wireless, networking, modulation, radio propagation, digital signal
`
`processing, and statistics for over 20 years.
`
`4. My academic background in electrical engineering provides a tech-
`
`nical foundation for work in digital communications. I received a Bachelor of Arts
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`degree in Mathematics and Physics from Dartmouth College in 1968. I then at-
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`tended Stanford University, where I received a Master of Science in 1971 and a
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`Doctor of Philosophy in 1975, both in Electrical Engineering.
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`5. While pursuing my Ph.D., I worked part-time for Probe Systems, and
`
`then full-time from 1975 to 1979 as a Senior Engineering Specialist. In this posi-
`
`tion, I was responsible for technical impact and management of defense programs
`
`(including ARPA) requiring innovative signal processing techniques (SIGINT,
`
`ELINT). I analyzed sophisticated communications methods and developed effec-
`
`tive DSP techniques for complex radio signals, including spread spectrum and low
`
`probability of intercept.
`
`6.
`
`In 1979 I was Vice President of a startup company called Spatial In-
`
`corporated, where I was responsible for engineering and manufacturing manage-
`
`ment. Our best-of-class products were based on complex ultra-linear amplifier
`
`technology. In 1981 I became Staff to Vice President, Engineering for Litton Ap-
`
`plied Technology. At Litton, I was responsible for the direction of the independent
`
`research effort supporting development of integrated computer/receiver platforms
`
`for the Defense Department. In 1983, I transitioned to Telebit Corporation, where I
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`served as Director of Development. At Telebit, I supervised fifteen development
`
`engineers in software and hardware modem design and development. I led a rapid
`
`and successful digital signal processing effort (over fifty thousand lines of code on
`
`Texas Instruments 320 DSP) that resulted in numerous Product of the Year awards.
`
`I also contributed as an individual developer of a unique modulation technology
`
`(now referred to as OFDM), allowing Telebit to become a market leader against
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`established competitors in less than two years. During my time at Telebit, I also
`
`obtained four key patents on orthogonal frequency division multiplexing (OFDM),
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`each of which has been cited over 100 times by later patents. These inventions are
`
`now incorporated in wireless (both cellular and Wi-Fi), DSL, and most digital
`
`broadcast standards.
`
`7.
`
`From 1990 to 1996, I was Director, Systems Architecture/WAN
`
`Technology at Canon Research. At Canon, I directed the digital telecommunica-
`
`tions development efforts and was responsible for the analysis, architecture, and
`
`implementation of emerging technologies, including ISDN and telecommunica-
`
`tions networking. I managed engineering teams with engineers at multiple levels,
`
`including several with Ph.D.s. I participated as a board member of California ISDN
`
`Users Group and testified before the California Public Utilities Commission.
`
`8.
`
`Since 1995 I have worked as a technologist supporting major intellec-
`
`tual property disputes arising from patent disputes, standards groups, and trade se-
`
`cret issues both in the United States and abroad. Technologies that I have consulted
`
`on include the IEEE 802.11 wireless standard, cellular technology, GPS, ISDN,
`
`digital modulation, DSL, OFDM, error correction, digital signal processing, spread
`
`spectrum, and packet systems.
`
`9. My Curriculum Vitae is attached as Ex. 2010, which contains further
`
`details on my education, experience, publications, and other qualifications to ren-
`
`
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`der an expert opinion. I am billing my work on this case at a rate of $400.00 per
`
`hour, with reimbursement for actual expenses. My compensation is not contingent
`
`upon the outcome of this inter partes review.
`
`III. Materials Considered
`
`10.
`
`In forming my opinions expressed in this declaration, I have consid-
`
`ered and relied upon my education, background, and experience. I reviewed the Pe-
`
`tition filed by Petitioners along with relevant exhibits to the Petition, including the
`
`declaration of Dr. Haas (Ex. 1009), the ’127 patent (Ex. 1001), and the ’127 patent
`
`file history (Ex. 1008).
`
`11. Specifically, I have reviewed and relied upon the following list of ma-
`
`terials in preparation of this declaration:
`
` Petition for Inter Partes Review of U.S. Patent No. 7,269,127
`
` Declaration of Dr. Zygmunt Haas (Ex. 1009)
`
` The ’127 patent (Ex. 1001)
`
` Schmidl (Ex. 1002)
`
` Arslan (Ex. 1003)
`
` Kim (Ex. 1004)
`
` Heiskala (Ex. 1006)
`
` Deposition Transcript of Dr. Zygmunt Haas (Ex. 2003)
`
` Decision to Institute Inter Partes Review (Paper No. 11)
`
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`12.
`
`I have also considered all other materials cited herein.
`
`IV. Applicable Legal Standards.
`
`A. My Understanding of Obviousness.
`
`13.
`
`I understand that a patent claim is invalid if the claimed invention
`
`would have been obvious to a person of ordinary skill in the field at the time the
`
`application was filed. This means that even if all of the requirements of the claim
`
`cannot be found in a single prior art reference that would anticipate the claim, the
`
`claim can still be invalid.
`
`14. As part of this inquiry, I have been asked to consider the level of ordi-
`
`nary skill in the field that someone would have had at the time the claimed inven-
`
`tion was made. In deciding the level of ordinary skill, I considered the following:
`
`
`
`
`
`
`
`the levels of education and experience of persons working in the field;
`
`the types of problems encountered in the field; and
`
`the sophistication of the technology.
`
`15. To obtain a patent, a claimed invention must have, as of the priority
`
`date, been nonobvious in view of the prior art in the field. I understand that an in-
`
`vention is obvious when the differences between the subject matter sought to be
`
`patented and the prior art are such that the subject matter as a whole would have
`
`been obvious at the time the invention was made to a person having ordinary skill
`
`in the art.
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`16.
`
`I understand that to prove that prior art or a combination of prior art
`
`renders a patent obvious, it is necessary to: (1) identify the particular references
`
`that, singly or in combination, make the patent obvious; (2) specifically identify
`
`which elements of the patent claim appear in each of the asserted references; and
`
`(3) explain how the prior art references could have been combined in order to cre-
`
`ate the inventions claimed in the asserted claim.
`
`17.
`
`I understand that certain objective indicia can be important evidence
`
`regarding whether a patent is obvious or nonobvious. Such indicia include: (1)
`
`commercial success of products covered by the patent claims; (2) a long-felt need
`
`for the invention; (3) failed attempts by others to make the invention; (4) copying
`
`of the invention by others in the field; (5) unexpected results achieved by the in-
`
`vention as compared to the closest prior art; (6) praise of the invention by the in-
`
`fringer or others in the field; the taking of licenses under the patent by others; (7)
`
`expressions of surprise by experts and those skilled in the art at the making of the
`
`invention; and (8) the patentee proceeded contrary to the accepted wisdom of the
`
`prior art.
`
`B. My Understanding of Claim Construction.
`
`18.
`
`I understand that, during an inter partes review, claims are to be given
`
`their broadest reasonable construction in light of the specification as would be read
`
`by a person of ordinary skill in the relevant art.
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`V. Level of Ordinary Skill in the Art.
`
`19. Based on the disclosure of the ’127 patent, one of ordinary skill in the
`
`art would have a Bachelor’s degree in Electrical Engineering, Computer Science,
`
`or an equivalent field as well as at least 3–5 years of academic or industry experi-
`
`ence in communications systems, with significant exposure to communication the-
`
`ory including modulation and digital signal processing.
`
`VI. Overview of the Technology.
`
`20. The ’127 patent is titled “Preamble Structures for Single-Input, Sin-
`
`gle-Output (SISO) and Multi-Input, Multi-Output (MIMO) Communication Sys-
`
`tems.” (’127 patent, Ex. 1001, p. 1, element (54).) A “preamble structure contains
`
`an overhead for providing synchronization and parameter estimation, allowing a
`
`receiver to decode signals received from a transmitter.” (’127 patent, 2:1–3.) The
`
`’127 patent also discloses “pilot symbols [that] may be inserted at any point in the
`
`data blocks.” (’127 patent, 7:29–30.) The following paragraphs provide detail
`
`about the technologies disclosed in the ’127 patent.
`
`A. Orthogonal Frequency Division Multiplexing (OFDM)
`
`21. Certain embodiments of the ’127 patent are directed to training in or-
`
`thogonal frequency division multiplexing (OFDM) systems. These systems map
`
`binary information to complex symbols, encoding the information into the ampli-
`
`tude and/or phase of multiple carriers of a transmitted signal. One complex symbol
`
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`may represent a number of bits, but is represented by a complex number that may
`
`also be referred to as a sample. Transmitted OFDM signals preserve these complex
`
`symbols on orthogonal frequency-domain subcarriers. This signal structure allows
`
`broadband transmission and reception with low algorithmic complexity relative to
`
`conventional single-carrier signals.
`
`22. To accomplish the frequency domain transmission the system simul-
`
`taneously converts a number of these complex symbols from the frequency domain
`
`into the time domain by taking an inverse discrete Fourier transform (IDFT) result-
`
`ing in a block of samples, each of which carries information about each of the fre-
`
`quency domain complex symbols. Together with a cyclic prefix, which may simply
`
`be a copy of the last several samples of the block prepended to its beginning, this
`
`collection of samples forms a time-domain OFDM symbol. (’127 patent, 7:51–8:18
`
`and FIG. 3.)
`
`B.
`
`Training Symbols
`
`23. Training sequences are used in wireless communication systems to
`
`synchronize a receiver to a transmitter, as well as to provide estimation of channel
`
`parameters. Training designs at the time of invention were inefficient, especially
`
`when applied to multiple-antenna systems. (’127 patent, 2:66–3:12)
`
`24. Wireless transmitters often send known training sequences prior to
`
`transmitting data. The receiver knows these training sequences and thus can search
`
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`for their presence in the received signal and then can estimate distortion caused by
`
`frequency offset, electromagnetic propagation, or other transmission impairments
`
`between the transmitter and receiver. Assuming that such distortion is constant for
`
`some transmission period, the receiver can use the estimates to correct for distor-
`
`tion of the data, which is unknown to the receiver.
`
`25. OFDM training requirements differ from conventional modulations
`
`because of this frequency domain aspect, and are more sensitive to frequency off-
`
`set than conventional digital systems.
`
`26. At the time of invention, the excessive amount of transmission time
`
`required for training reduced the overall efficiency of communication. This excess
`
`largely stemmed from the provision of different training sequences for different
`
`purposes. For example, the ’127 patent states that “the IEEE Standard 802.11a pre-
`
`amble structure includes a short sequence, which provides time synchronization
`
`and coarse frequency offset estimation, followed by a long sequence, which pro-
`
`vides fine frequency and channel estimation.” (’127 patent, 3:1–5.) The newly de-
`
`veloped multiple-input multiple-output (MIMO) communication comprising “sig-
`
`nals [] typically transmitted over a common path … by multiple antennas” exacer-
`
`bated the inefficiencies of these existing sequences. (Id. at 1:54–56.)
`
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`C. The ’127 Patent
`
`27.
`
`In contrast to the art of record, the ’127 patent discloses a transmitter
`
`with a single encoder coupled to potentially multiple modulators and multiple an-
`
`tennas. The annotated FIG. A below illustrates such a transmitter, with an encoder
`
`that “encodes data … from a data source” (id. at 5:13–15) and “one or more modu-
`
`lators … to modulate signals for transmission over the [wireless] channel” (id. at
`
`5:32–34).
`
`
`FIG. A - Combination of FIGS. 1–3 of the ’127 patent
`28. As can be seen, the structure of the encoder is distinguishing in itself
`
`because of the pilot/training symbol inserter. This block inserts pilots in the fre-
`
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`quency domain, unlike the art of record. Furthermore, unlike Heiskala, the ’127 pa-
`
`tent couples a single encoder to a plurality of modulators as in claim 17. The fol-
`
`lowing sections provide the overall frame structure disclosed in the ’127 patent.
`
`1.
`The encoder element
`
`29. The disclosed transmitter’s encoder 18 includes a channel encoder 36
`
`that “adds parity to the signals so that the decoder [] can detect errors in the re-
`
`ceived channel encoded signals, which may occur … due to environmental condi-
`
`tions that affect the channel.” (’127 patent, 6:46–50.) The encoder also includes a
`
`symbol mapper 38 that “map[s] channel encoded signals into data blocks.” (Id. at
`
`6:55–56.) In this context, the ’127 patent uses the term “symbol” to refer to ele-
`
`ments from an alphabet such as binary phase shift keying (BPSK) or quadrature
`
`phase shift keying (QPSK), which are modulated on the OFDM subcarriers. (Id. at
`
`6:59–65.)
`
`30.
`
`If the encoder is part of a MIMO system, it may include a space-time
`
`processor 40, which “encode[s] a stream of data blocks, received from the symbol
`
`mapper 38, through space-time processing.” (Id. at 7:3–4.) The encoder also in-
`
`cludes a pilot/training symbol inserter 46 that “typically provides pilot blocks and
`
`training blocks that are inserted into (or combined with) the data blocks.” (Id. at
`
`7:23–25.) The operation of the pilot/training symbol inserter is discussed below.
`
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`2.
`The modulator element
`31. The disclosed transmitter’s modulator contains a “serial-to-parallel
`
`converter 50 [that] converts the training blocks and data blocks from a serial for-
`
`mat to a parallel format for further processing by other components.” (Id. at 7:59–
`
`62.) The IDFT stage 52 “converts these blocks from the frequency domain to the
`
`time domain.” (Id. at 8:4–5.) For a data block, the IDFT stage converts N frequen-
`
`cy domain samples into N time domain samples using an N-point IDFT. (Id. at
`
`8:6–11.) The cyclic prefix inserter 54 then “inserts an additional number of sam-
`
`ples ‘G’ with each data block and training block to form data symbols and training
`
`symbols.” (Id. at 8:13-15.) The modulator then converts the samples from parallel
`
`to serial, converts the digital samples to analog, and uses a mixer to up-convert the
`
`analog signal to RF so that it may be amplified and transmitted. (Id. at 8:19-34.)
`
`3.
`A frame structure embodiment from the ’127 patent
`32. Below I have annotated FIG. 6 of the ’127 patent to illustrate an ex-
`
`emplary frame structure. Focusing on Antenna Q, the frame structure 68 “includes
`
`a preamble structure 70 and a data structure 72.” (Id. at 10:58–59.) “The preamble
`
`structure 70 typically includes one or more training symbols 74” (Id. at 10:62–63)
`
`and “an enhanced training symbol 79, located at the beginning of the preamble
`
`structure.” (Id. at 11:3–5.) The training symbol 74 “includes a cyclic prefix 76 of
`
`length G and a training block 78 of length NI… [and] has a length of G+NI samples
`
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`in the time domain.” (Id. at 10:65–11:2.) Therefore, a “symbol” in the context of a
`
`training symbol denotes a section of samples including a cyclic prefix and the time
`
`domain output of the IDFT stage.
`
`
`
`FIG B
`33. The data structure 72 “includes one or more data symbols 80 …
`
`[which each] includes a cyclic prefix 76 and a data block 82.” (Id. at 11:28-30.) As
`
`disclosed in the ’127 patent, “pilot symbols may also be intermittently inserted into
`
`the data symbols 80 by the pilot/training symbol inserter 46.” (Id. at 11:45-47.)
`
`FIGS. 2 and 3 illustrate that the pilot symbols are “inserted periodically into the da-
`
`ta blocks” (id. at 7:28) in the frequency domain.
`
`34. The pilot/training symbol inserter outputs both training symbols and
`
`pilot symbols. However, “[t]he term training blocks refers to one or more contin-
`
`uous sections of symbols provided by the pilot/training symbol inserter 46” (id. at
`
`
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`7:30-32 (emphasis added)), whereas pilot symbols “are inserted periodically into
`
`the data blocks.” (Id. at 7:28.) Furthermore, “[t]raining blocks are preferably in-
`
`serted into preamble structures at the beginning of the frame structures and trans-
`
`mitted once per frame structure.” (Id. at 7:32-34.)
`
`35. As noted above, “the preamble structure 70 contains one symbol re-
`
`ferred to…as an enhanced training symbol 79, located at the beginning of the pre-
`
`amble structure 70.” (Id. at 11:2-5.) The training block 78 of the enhanced training
`
`symbol 79 is divided into several sections” (id. at 11:5-6) that are used for various
`
`purposes. For example, the training block 78 in FIG. 7, reproduced below, is divid-
`
`ed into four sections (86-2 through 86-5) and the cyclic prefix 76 forms a fifth sec-
`
`tion 86-1 of the enhanced training symbol 84. (Id. at 13:32-38.)
`
`
`These sections can be divided and combined into various intervals that are used for
`
`different purposes. For example, “[a] first interval 88 of the enhanced training
`
`symbol 84 spans the first two sections 86-1, 86-2…[and is used for] time synchro-
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`nization and coarse frequency offset estimation.” (Id. at 13:50-54.) A second inter-
`
`val 90, which includes sections 86-3 and 86-4, does not overlap with the first inter-
`
`val 88 and “includes sequences for providing parameter estimation, such as chan-
`
`nel estimation and noise variance estimation.” (Id. at 13:59-60.) A third interval 92
`
`overlaps with the first and second intervals and “provides sequences for fine fre-
`
`quency offset estimation.” (Id. at 13:63-64.) FIGS. 8 and 9 provide alternative em-
`
`bodiments of the enhanced training symbol with various sections, intervals, and an-
`
`tennas.
`
`VII. Understanding of Certain Terms
`
`A.
`
`36.
`
`“pilot symbol”
`
`In the context of the ’127 patent, the broadest reasonable interpreta-
`
`tion for the term “pilot symbol” is a “frequency domain symbol for refining the
`
`calibration of a receiver to a transmitter.” Setting forth the broadest reasonable in-
`
`terpretation for the term “pilot symbol” in the context of the ’127 patent is im-
`
`portant to the determination of whether the independent claim 1 and dependent
`
`claims 2, 3 and 5 are patentable over the combination of Schmidl and Arslan.
`
`37. The Board found “for purposes of this Decision that the broadest rea-
`
`sonable construction” for the term pilot symbol “is apparent from the context of the
`
`claims and specification.” (Institution Decision, p. 8.) I agree with the Board that
`
`the claims and the specification dictate the basis for the broadest reasonable inter-
`
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`pretation in this case. However, express construction is necessary to avoid confu-
`
`sion as to what type of symbol a pilot symbol is. Specifically, the word “symbol,”
`
`by itself or absent modifier, is a term of art that describes several different concepts
`
`in the field of communications and even within the ’127 patent. Petitioners’ expert,
`
`Dr. Haas, agrees, testifying at deposition that the term “symbol” “can have differ-
`
`ent meanings in different context. It’s -- it’s a term which is used to signify differ-
`
`ent things in different contexts.” (Haas Depn., 53:3-8.)
`
`1.
`A “pilot symbol” is a frequency domain symbol.
`38. Dr. Haas opined that a “symbol” may be a frequency domain symbol
`
`or a time domain symbol, “depending on which point in the whole process the par-
`
`ticular use is -- applies.” (Haas Depn., 76:2-3.) I agree with Dr. Haas. In the con-
`
`text of the ’127 patent, the designation of a “symbol” as a frequency domain sym-
`
`bol (at least one use, pilot symbol) or time domain symbol (at least two uses, train-
`
`ing symbol and data symbol) depends on the point of the transmission or reception
`
`process where the symbol is being used. In the ’127 patent the “pilot symbol” in-
`
`serted into a data block by the encoder of the transmitter is a frequency domain
`
`symbol.
`
`39.
`
`I have prepared FIG. C which illustrates a transmitter 14 that incorpo-
`
`rates the encoder 18 of FIG. 2 and a modulator 24 of FIG. 3, showing that the “pi-
`
`lot symbol” is a frequency domain symbol. The encoder 18 includes a “symbol
`
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`mapper 38, which receives channel encoded signals from the channel encoder 36.”
`
`(’127 patent, 6:52–54.) “The symbol mapper 38 is typically configured to map
`
`channel encoded signals into data blocks.” (’127 patent, 6:54–56.) A data block in-
`
`cludes one or more samples. The space-time processor 40 of the encoder 18 “is
`
`typically configured to encode a stream of data blocks, received from the symbol
`
`mapper 38, through space-time processing to form the data block designated for
`
`different TDBs [transmit diversity branches] 22 ….” (’127 patent, 7:2–5.)
`
`FIG. C - Transmitter of the ’127 patent
`
`40. The encoder 18 also includes a pilot/training symbol inserter 46 that
`
`provides pilot blocks (symbols) “which are inserted periodically into the data
`
`
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`blocks.” (’127 patent, 7:26–28.) “Typically, pilot symbols may be inserted at any
`
`point in the data blocks.” (’127 patent, 7:28–30.)
`
`41. The pilot symbols are frequency domain symbols inserted into a data
`
`block in the frequency domain. The data blocks (having the inserted pilot symbols)
`
`are provided to the IDFT stage 52 of the modulator 24. The IDFT stage 52 “con-
`
`verts the samples in the frequency domain to N samples for each data block … in
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`the time domain.” (’127 patent, 8:6–11.) I understand that Petitioners’ expert
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`agrees that everything to the left of IDFT stage 52 of the modulator 24 is in the
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`frequency domain:
`
`So I believe that the ’127 patent uses the OFDM symbol, the
`term “OFDM symbol” or symbol differently depending on
`which point in the whole process the particular use is -- applies.
`So if you -- for example, I was trying to find -- if we take Fig-
`ure -- Figure 1, the -- of the ’127 patent, if you -- I’m sorry. Not
`Figure 1. That’s fine. Figure -- Figure 3 would be better. You
`have the IDTF [sic]. The IDTF [sic], which is the inverse dis-
`crete Fourier transform, to the left of this, which is what I
`am going to refer as frequency domain that’s -- and to the
`right of the IDTF [sic] is – is what I’m going to refer as time
`domain. In the frequency domain, the OFDM symbol is – cor-
`responds to what the patent refers to as block, as a data block or
`training symbol block. To the right of the IDTF [sic] symbol --
`sorry, to the right of the IDTF [sic] box, the patent refers to
`symbol as being the combination of the block plus the guard.
`
`
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`

`

`So in time domain, a symbol would be block plus guard. In the
`frequency domain, there’s no guard in frequency domain, so it
`will be only the block. When I refer to guard, I just want to re-
`mind ourselves that I’m talking about cyclic prefix.
`
`(Haas Depn. 75:25-76:23 (emphasis added).) I agree with the statements made by
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`Dr. Haas at his deposition and there appears to be no dispute that pilot symbols are
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`frequency domain symbols inserted into data blocks in the frequency domain.
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`42. To illustrate the high-level process performed by the transmitter, I
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`prepared FIG. D depicting a data block having four samples, after processing by
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`space-time processor 40. The pilot/training inserter 46 of the encoder inserts pilot
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`symbols into the data block – in this case alternating pilot symbol samples between
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`data block samples. Because this process occurs before the IDFT, the pilot symbols
`
`must be frequency domain symbols, and the insertion process occurs in the fre-
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`quency domain.
`
`
`
`
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`

`

`
`
`FIG. D
`43. The IDFT stage 52 of the modulator converts the data block with pilot
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`symbols from the frequency domain into a time domain data block. At this point,
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`the cyclic prefix inserter of the modulator appends a cyclic prefix to the time do-
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`main data block creating a data symbol. As confirmed by Dr. Haas, the data sym-
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`bol, having a cyclic prefix, is a time domain symbol. (Haas Depn., 81:2–12.)
`
`2.
`
`A “pilot symbol” refines “the calibration of a receiver to a
`transmitter.”
`44. A “pilot symbol” is known to both the transmitter and receiver and is
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`“transmitted with data blocks to calibrate (i.e., synchronize) the receiver 16 to the
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`transmitter 14 on a small scale.” (’127 patent, 7:40–42.) That is, the “pilot symbol”
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`refines the calibration that exists between a transmitter and receiver. Dr. Haas also
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`
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`- 20 -
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`

`

`agrees that “pilot symbols” refine the calibration between a receiver and transmit-
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`ter:
`
`Q. Okay. And what’s the difference between synchronization that’s
`performed using the preamble and synchronization that’s per-
`formed using a pilot?
`
`A. Typically, and again I emphasize typically, the training se-
`quences are used to provide initial synchronization and the pi-
`lots are typically used to provide to resynchronize the trans-
`missions.
`
`Q. Okay. And is that the way the training symbols and pilot sym-
`bols are being used in the ’127 patent?
`
`A. I believe that this is the way that the training symbols and pilot
`symbols are used in the ’127 patent.
`
`Q. Okay. And you used the term “initial synchronization.” What
`do you mean by initial synchronization?
`
`A. Well, if you send a frame and this is the only thing that you
`send, then at the beginning of the frame, there’s presumably
`no synchronization between the transmitter and the receiver.
`The training sequence, or the training symbol more precisely,
`the training symbol will provide the initial synchronization.
`As the frame goes on, so to speak, the channel will change,
`and the synchronization may be -- may be -- may need to
`be adjusted or recalibrated, so to speak, and that’s where
`the pilot symbols will help with.
`
`
`
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`

`

`(Haas Depn., 57:11–68:13 (emphasis added).)
`3.
`Petitioners’ proposed construction is not the broadest rea-
`sonable interpretation.
`
`45.
`
`In the Petition at page 23, the Petitioner proposed construing the term
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`“pilot symbol” as “a symbol located in the data structure and used for performing
`
`synchronization.” I do not agree with that proposed construction because it is over-
`
`ly broad and does not take into account the context of the term in the ’127 patent.
`
`46. This overly-broad construction by Petitioner does not distinguish be-
`
`tween other symbols described in the ’127 patent. The ’127 patent describes sever-
`
`al different symbols. including a pilot symbol, a training symbol, and a data sym-
`
`bol. Training symbols and data symbols are time domain symbols because both are
`
`formed after the IDFT by “insert[ing] an additional number of samples ‘G’ [a cy-
`
`clic prefix] with each data and training block.” (’127 patent, 8:13–14.) Once again,
`
`I agree with the testimony of Dr. Haas that a “training symbol” and a “data sym-
`
`bol” each comprise a number of continuous samples in the time domain. (Haas
`
`Depn., 76:18–77:17.) As discussed above, pilot symbols are frequency domain
`
`samples because they are placed within data blocks in the frequency domain. To
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`illustrate, I have prepared FIG. E showing how a “pilot symbol” comprises samples
`
`in the frequency domain while a “training symbol” and a “data symbol” are both
`
`comprised of a cyclic prefix and a number of time domain samples highlighting
`
`data blocks and training blocks in both the frequency and time domains.
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`
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`

`

`
`
`FIG. E
`47. Petitioners’ contention that a “pilot symbol” is a symbol “used for
`
`performing synchronization” fails to distinguish between a preamble training sym-
`
`bol, which is used for coarse calibration (synchronization), and a pilot symbol,
`
`which is used to refine the calibration between a receiver and transmitter. Although
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`training symbols are also “used to periodically calibrate the receiver 16 to the
`
`transmitter 14” (see ’127 patent, 7:44–45), they provide such calibration on a large
`
`scale by occupying the entire bandwidth such that “training symbols may be
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`unique for each su