`__________________
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`___________________
`
`ERICSSON INC. AND TELEFONAKTIEBOLAGET
`LM ERICSSON,
`Petitioner
`
`v.
`
`INTELLECTUAL VENTURES II LLC,
`Patent Owner
`___________________
`
`Patent 7,787,431
`
`Title: METHODS AND APPARATUS FOR MULTI-CARRIER
`COMMUNICATIONS WITH VARIABLE CHANNEL
`BANDWIDTH
`_____________________
`
`PETITION FOR INTER PARTES REVIEW
`
`
`
`Pursuant to the provisions of 35 U.S.C. §§ 311-319, Petitioner Ericsson Inc.
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`and Telefonaktiebolaget LM Ericsson (collectively, “Ericsson”) hereby petitions the
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`Patent Trial and Appeal Board to institute an inter partes review of claims 1, 2, 8-12,
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`and 18-22 of United States Patent No. 7,787,431 (“the ’431 patent,” ERIC-1001)
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`that issued on August 31, 2010, to Xiaodong Li, et al. According to USPTO
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`records, the ’431 patent is currently assigned to Intellectual Ventures II LLC (“IV”).
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`
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`
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`Petition for Inter Partes Review of U.S. 7,787,431
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`TABLE OF CONTENTS
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`I. Mandatory Notices ................................................................................................ 1
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`A. Real Party-in-Interest .................................................................................. 1
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`B. Related Matters ........................................................................................... 1
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`C. Lead and Back-up Counsel and Service Information .................................... 1
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`II. Grounds for Standing ............................................................................................ 2
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`III. Relief Requested ................................................................................................... 2
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`IV. The Reasons for the Requested Relief .................................................................... 2
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`A. Summary of the Related Technology and the ’431 Patent ............................ 2
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`B. The Prosecution History .............................................................................. 7
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`C. The Prior Art of the Present Petition ............................................................ 8
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`V. Reasons That Challenges Are Not Cumulative ..................................................... 15
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`VI. Identification of Challenges and Claim Construction............................................ 15
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`A. Challenged Claims .................................................................................... 15
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`B. Claim Construction ................................................................................... 16
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`1. Bandwidth ................................................................................................. 16
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`2. Core-Band ................................................................................................ 17
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`3. Primary Preamble ..................................................................................... 17
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`4. Peak-to-Average Ratio .............................................................................. 18
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`C. Statutory Grounds for Challenges .............................................................. 19
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`1. Challenge #1: Claims 8-11 and 18-21 are unpatentable under 35 U.S.C. §
`103(a) over Li, Yamaura, and Zhuang ........................................................... 20
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`Petition for Inter Partes Review of U.S. 7,787,431
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`2. Challenge #2: Claims 1, 2, 12, and 22 are unpatentable under 35 U.S.C. §
`103(a) over Li, Yamaura, Zhuang, and Beta .................................................. 39
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`3. Challenge #3: Claims 8-11 and 18-21 are unpatentable under 35 U.S.C. §
`103(a) over Li, Yamaura, Mody, Nobilet, and Popovic .................................. 47
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`4. Challenge #4: Claims 1, 2, 12, and 22 are unpatentable under 35 U.S.C. §
`103(a) over Li, Yamaura, Mody, Nobilet, Popovic, and Beta ......................... 56
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`VII. Conclusion .......................................................................................................... 60
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`ii
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`Petition for Inter Partes Review of U.S. 7,787,431
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` I. Mandatory Notices
`
`
`A. Real Party-in-Interest
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`
`
`
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`The real party-in-interest is Ericsson.
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`B. Related Matters
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`As of the filing date of this petition and to the best knowledge of Ericsson, the
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`’431 Patent is involved in the following litigations:
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` IV I LLC et al. v. AT&T Mobility LLC et al., 1-13-cv-01668 (D. Del. 2013).
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` IV I LLC et al. v. Leap Wireless Int’l et al., 1-13-cv-01669 (D. Del. 2013).
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` IV I LLC et al. v. Nextel Operations, et al., 1-13-cv-01670 (D. Del. 2013).
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` IV I LLC et al. v. T-Mobile USA Inc. et al., 1-13-cv-01671 (D. Del. 2013).
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` IV I LLC et al. v. United States Cellular Corp., 1-13-cv-01672 (D. Del. 2013).
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`C. Lead and Back-up Counsel and Service Information
`
`Lead Counsel
`J. Andrew Lowes
`HAYNES AND BOONE, LLP
`2323 Victory Ave. Suite 700
`Dallas, TX 75219
`
`Phone: (972) 680-7557
`Fax: (214) 200-0853
`andrew.lowes.ipr@haynesboone.com
`USPTO Customer No. 27683
`USPTO Reg. No. 40,706
`
`Back-up Counsel
`David M. O’Dell
`HAYNES AND BOONE, LLP
`2323 Victory Ave. Suite 700
`Dallas, TX 75219
`
`Phone: (972) 739-8635
`Fax: (214) 200-0853
`david.odell.ipr@haynesboone.com
`USPTO Customer No. 27683
`USPTO Reg. No. 42,044
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`Please address all correspondence to lead and back-up counsel. Ericsson also
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`consents to electronic service by email.
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`
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`1
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`
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`II. Grounds for Standing
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`Petition for Inter Partes Review of U.S. 7,787,431
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`Ericsson certifies that the ’431 patent for which review is sought is available for
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`inter partes review and that Ericsson is not barred or estopped from requesting inter
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`partes review challenging the patent claims on the grounds identified in the petition.
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`III. Relief Requested
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`Ericsson asks that the Board review the accompanying prior art and analysis,
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`institute a trial for inter partes review of claims 1, 2, 8-12, and 18-22 of the ’431 patent,
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`and cancel those claims as unpatentable.
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`IV. The Reasons for the Requested Relief
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`A. Summary of the Related Technology and the ’431 Patent
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`The ’431 patent relates generally to multi-carrier communication systems, such
`
`as systems that employ orthogonal frequency division multiplexing (OFDM). See
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`ERIC-1001, 1:43-47 and 2:36-38; See also, ERIC-1012, ¶ 19. “A basic structure of a
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`multi-carrier signal in the frequency domain is made up of subcarriers and, illustrated in
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`FIG. 3, which shows three types of subcarriers” – data subcarriers, pilot subcarriers, and
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`silent subcarriers. ERIC-1001, 3:23-32. Fig. 3 is reproduced below:
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`Petition for Inter Partes Review of U.S. 7,787,431
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`Note that in Fig. 3, which is admitted prior art, subcarriers are grouped as various
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`subchannels. The ’431 patent describes a rationale for the subcarrier groupings that
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`“[t]he data subcarriers can be arranged into groups called subchannels to support
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`scalability and multiple-access.” Id., 3:33-34.
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`The claims of the ’431 patent conceptually relate to and can be divided into three
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`aspects of communication technology:
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`(1) variable bandwidth multi-carrier systems;
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`(2) characteristics of a core-band; and
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`(3) properties of a primary preamble, which is transmitted in the core-band.
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`Petition for Inter Partes Review of U.S. 7,787,431
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`For the sake of example, claim 1 is reproduced below, annotated to show the three
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`aspects identified above.
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` These aspects form a conceptual framework for
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`understanding the claims. See, ERIC-1012, ¶¶ 24-25.
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`1. In a variable bandwidth wireless communication system
`communicating under multiple different communication schemes that
`each have a different bandwidth, a process performed by a base station
`of generating an information bearing signal for wireless transmission,
`the process comprising:
`[Aspect (1):]
`utilizing by the base station a number of subcarriers to construct a
`variable bandwidth wireless channel;
`utilizing by the base station groups of subcarriers, wherein each
`group includes a plurality of subcarriers;
`maintaining a fixed spacing between adjacent subcarriers;
`adding or subtracting, by the base station, groups of subcarriers to
`scale the variable bandwidth wireless channel and achieve an operating
`channel bandwidth; and
`[Aspect (2):]
`wherein a core-band, including a plurality of subcarrier groups,
`substantially centered at an operating center frequency of the different
`communication schemes, is utilized by the base station as a broadcast
`channel carrying radio control and operation signalling, where the core-
`band is substantially not wider than a smallest possible operating
`channel bandwidth of the system; and
`[Aspect (3):]
`wherein the information bearing signal has a primary preamble
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`Petition for Inter Partes Review of U.S. 7,787,431
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`sufficient for basic radio operation and wherein:
`the primary preamble is a direct sequence in the time domain
`with a frequency content confined within the core-band, or is an
`orthogonal frequency-divisional multiplexing (OFDM) symbol
`corresponding to a particular frequency pattern within the core-
`band; and
`wherein properties of the primary preamble comprise:
`an autocorrelation having a large correlation peak with respect
`to sidelobes;
`a cross-correlation with other primary preambles having a
`small cross-correlation coefficient with respect to power of other
`primary preambles; and
`a small peak-to-average ratio; and wherein a large number of
`primary preamble sequences exhibit the properties.
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`As explained later in the prosecution history section below, the first two aspects
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`were conceded during prosecution as being in the prior art, and it was the third aspect
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`relating to the specific properties of the preamble that resulted in claim allowance. We
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`agree with the Examiner that (1) variable bandwidth multi-carrier systems, and (2)
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`characteristics of a core-band were well known in the art. Furthermore, additional
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`references provided herein, which were not considered by the Examiner, disclose claim
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`aspect (3) – properties of a primary preamble, which is transmitted in the core-band.
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`More specifically, and referring to aspect (1), the ’431 patent states: “In some
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`embodiments, the variable channel bandwidth is realized by adjusting the number of
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`usable subcarriers.” ERIC-1001, 4:25-26. In one embodiment, “[t]he variable channel
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`bandwidth is realized by adjusting the number of usable subcarriers, whose spacing is
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`set constant.” Id., 4:41-42. According to the equations in Fig. 2, which is admitted prior
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`art, bandwidth is proportional to the number of subcarriers. See id., Fig. 2 and ERIC-
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`1012, ¶ 21. The same concepts are disclosed in U.S. Patent No. 6,904,283 (“Li”)
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`utilized below to illustrate these prior art features.
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`Referring to aspect (2), the ’431 patent states: “To facilitate the user terminals to
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`operate in a variable bandwidth (VB) environment, specific signaling and control
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`methods are required. Radio control and operation signaling is realized through the use
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`of a core-band (CB).” ERIC-1001, 4:64-67. The core-band is used to transmit control
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`signals and control channels: “[i]n one embodiment relevant or essential radio control
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`signals such as preambles, ranging signals, bandwidth request, and/or bandwidth
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`allocation are transmitted within the CB.” Id., 5:8-13 (emphasis added). An example of
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`a narrow band to transmit control signals in an OFDM system is disclosed in U.S.
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`Patent No. 7,782,750 (“Yamaura”). The control signals in Yamaura are transmitted in a
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`broadcast preamble using subcarriers centered at an operating frequency.
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`Referring to aspect (3), which was added during prosecution to gain allowance
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`of the claims, claim 1 recites certain properties for the preamble sequences, including
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`autocorrelation, cross-correlation, and peak-to-average ratio properties. However, the
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`’431 patent specification does not disclose any examples of preamble structures
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`Petition for Inter Partes Review of U.S. 7,787,431
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`achieving the desired properties. Even though no examples are disclosed in the ’431
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`patent, it was well known to utilize preamble sequences with the claimed properties.
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`For example, as explained herein, U.S. Patent No. 7,426,175 (“Zhuang”) discloses a
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`large number of preamble sequences with the requisite autocorrelation, cross-
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`correlation, and peak-to-average ratio properties. Additionally, as explained herein,
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`Exhibit ERIC-1006 (“Nobilet”) also discloses a large number of sequences with the
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`requisite properties.
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`Accordingly, as demonstrated herein, features of the claims of the ’431 patent
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`related to these three aspects – (1) variable bandwidth multi-carrier systems; (2)
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`characteristics of a core-band; and (3) properties of a primary preamble, which is
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`transmitted in the core-band – were well-known in the art at the time the ’431 patent
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`was filed.
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`B. The Prosecution History
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`Original claim 1 of the ’431 patent was rejected as being unpatentable over U.S.
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`Patent No. 6,175,550 (Van Nee) and another U.S. patent in an office action dated April
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`28, 2009. ERIC-1010, pp. 191-193. Among other claims, claim 3, a claim directed to
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`properties of a primary preamble, was indicated as allowable. See id., p. 207. After a
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`final rejection, the Applicants authorized an Examiner’s Amendment for claim 1 (see
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`id., p. 53), which included the subject matter of claim 3. Specifically, the Examiner’s
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`Amendment added the entirety of aspect (3), described above with reference to claim 1.
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`Petition for Inter Partes Review of U.S. 7,787,431
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`See id., p. 277. In explaining the allowable subject matter, the Examiner stated that the
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`prior art “discloses a variable bandwidth system by adjusting the number of
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`subcarriers”, and “discloses a primary channel with a central channel in which dynamic
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`link assignment is constrained in the central channel to maintain synchronization,”
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`which correspond to aspects (1) and (2), above. ERIC-1010, pp. 53-54. As explained
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`in further detail below, references provided herein, which were not before the
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`Examiner, teach the features of aspect (3).
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`C. The Prior Art of the Present Petition
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`Li. U.S. Patent No. 6,904,283 (“Li”), having a priority date of April 17, 2001,
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`qualifies as prior art under 35 U.S.C. § 102(e)(pre-AIA). Li “relates to the field of
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`wireless communications; more particularly, the invention relates to multi-cell, multi-
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`subscriber wireless systems using orthogonal frequency division multiplexing
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`(OFDM).” ERIC-1002, 1:11-14. Li explains that “[i]n OFDM, a wide bandwidth is
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`divided into multiple narrow-band subcarriers, which are arranged to be orthogonal
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`with each other.” Id., 1:19-21. The subcarriers are divided into clusters. See ERIC-
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`1012, ¶ 34. For example, “FIG. 1A illustrates multiple subcarriers, such as subcarrier
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`101, and cluster 102. A cluster, such as cluster 102, is defined as a logical unit that
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`contains at least one physical subcarrier, as shown in FIG. 1A. A cluster can contain
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`consecutive or disjoint subcarriers. The mapping between a cluster and its subcarriers
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`can be fixed or reconfigurable. In the latter case, the base station informs the subscribers
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`when the clusters are redefined. In one embodiment, the frequency spectrum includes
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`512 subcarriers and each cluster includes four consecutive subcarriers, thereby resulting
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`in 128 clusters.” Id., 5:18-27. That is, in Li’s Fig. 1A, for example, four consecutive
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`subcarriers form a cluster.
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`A base station can assign a subscriber one or more clusters of subcarriers. See
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`ERIC-1012, ¶ 35. At a later time, a number of clusters can be increased, thereby
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`increasing bandwidth (i.e., the bandwidth is variable). See id. For example, “the base
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`station first allocates multiple clusters, referred to herein as the basic clusters, to
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`establish a data link between the base station and the subscriber. The base station then
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`subsequently allocates more clusters, referred to herein as the auxiliary clusters, to
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`the subscriber to increase the communication bandwidth.” ERIC-1002, 6:43-48
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`(emphasis added).
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`Yamaura. U.S. Patent No. 7,782,750 (“Yamaura”), having a priority date of
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`February 20, 2003, qualifies as prior art under 35 U.S.C. § 102(e)(pre-AIA). Yamaura
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`“relates to a radio communication method, a radio communication system, [and] a radio
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`communication base station … particularly suitable for radio transmission based on
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`OFDM modulation (Orthogonal Frequency Division Multiplexing).” ERIC-1003,
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`1:10-18. Furthermore, “[t]he present invention was completed to reduce loads in a base
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`station or a terminal station when control signals are transmitted from a base station to a
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`terminal station in the radio communication system of the type mentioned above.” Id.,
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`5:64-67.
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`Yamaura points out that in conventional OFDM systems “the signal to call a
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`terminal station from a base station is transmitted, with all information placed on
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`subcarriers in the transmission band, and the called terminal station receives all the
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`subcarriers to receive the calling signal. This means that the terminal station has to
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`receive and decode the band signal (corresponding to 20 MHz) every 2 ms regardless of
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`presence or absence of data being transmitted and received. It follows, therefore, that
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`large quantities of signals have to be processed even when no information data is
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`transmitted and received.” Id., 5:39-46. In order to address this issue, Yamaura
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`discloses a system in which “part of control signals addressed to a terminal station from
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`a base station is transmitted by means of a carrier whose band is narrower than that
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`for said multi-carrier signals […]” Id., 6:5-8. An example of control signals narrower
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`than that for a multi-carrier signal is presented in Fig. 16, reproduced below. In the
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`figure, subcarriers SC1 and SC2 carry control signals. See, e.g., id., 21:11-15.
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`The control signals in Yamaura are transmitted in a broadcast preamble using the
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`subcarriers centered at an operating frequency. See ERIC-1012, ¶ 40-41. For example,
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`referring to Fig. 17, “[t]he broadcast burst consists of BCH for the multiple addressing
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`of broadcast preamble and base station information, FCH to inform each terminal
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`station of the traffic channel allocation in the same frame, and ACH for reply to RCH
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`used for calling from the terminal station. In the case of this embodiment, the two
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`subcarriers SC1 and SC2 shown in FIG. 16 are used for transmission of specific
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`control signals in the sections of broadcast preamble, BCH, and FCH in the broadcast
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`burst.” ERIC-1003, 21:7-15 (emphasis added). Fig. 17 is reproduced below (color
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`annotations added). See ERIC-1012, ¶ 43.
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`
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`In Yamaura, the narrowband control signals, such as those transmitted using
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`SC1, and SC2 above, are used to provide a call signal to a terminal station so that the
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`terminal station can judge whether the terminal station is being called. See ERIC-1012,
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`¶ 49. “Part of the control signals to be transmitted from the base station to the terminal
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`station by means of the narrow-band carrier is, for example, a call signal to call terminal
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`stations individually or as a group. Upon reception of this call signal, the terminal
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`station can judge that there is a call from the base station.” ERIC-1003, 10:58-63.
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`Cross correlation detection is used to detect the narrowband control signal.
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`ERIC-1012, ¶ 47. For example, “FIG. 15 shows the constitution of the control signal
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`receiving unit 242 in the terminal station shown in FIG. 6. It is so constructed as to
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`receive the control signal by means of simple cross correlation detection.” ERIC-
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`1003, 19:64-67 (emphasis added). Thus, Yamaura recognizes the transmission of
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`preambles in a core-band as well as using cross correlation to detect the presence of the
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`control signals in the preamble.
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`Zhuang. U.S. Patent No. 7,426,175 (“Zhuang”), having a priority date of March
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`30, 2004, qualifies as prior art under 35 U.S.C. § 102(e)(pre-AIA). Zhuang addresses a
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`“need [that] exists for a method and apparatus for pilot signal or preamble transmission
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`that optimizes both the cross correlation between pilot signals, as well as optimizing
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`each pilot signal’s auto correlation.” ERIC-1004, 2:7-10. To address the need, “pilot
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`sequences are constructed from distinct ‘classes’ of chirp sequences that have an
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`optimal cyclic cross correlation property while satisfying the ideal cyclic auto-
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`correlation requirement. Utilization of chirp sequences for pilot sequences results in
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`pilot channels that have good cross correlation as well as having good auto-correlation.”
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`Id., 2:22-29.
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`“A pilot signal (or preamble) is commonly used for communication systems to
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`enable the receiver to perform a number of critical functions, including but not limited
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`to, the acquisition and tracking of timing and frequency synchronization, the estimation
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`and tracking of desired channels for subsequent demodulation and decoding of the
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`information data, the estimation and monitoring of the characteristics of other channels
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`for handoff, interference suppression, etc.” Zhuang, 1:12-19 (emphasis added). Thus,
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`Zhuang discloses that preambles and pilot signals are commonly used for
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`synchronization and channel estimation. Id.
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`Zhuang describes properties of “Generalized Chirp-Like” sequences, which are
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`used as preambles in an OFDM system and include good autocorrelation and
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`crosscorrelation, and low PAPR. See ERIC-1004 2:55-58, 5:9-15, and 6:5-6; See also,
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`ERIC-1012, ¶ 56.
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`Beta. TR101146v3.0.0, “Universal Mobile Telecommunications System
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`(UMTS); UMTS Terrestrial Radio Access (UTRA); Concept evaluation (UMTS 30.06
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`version 3.0.0)”, December 1997 (“Beta”), qualifies as prior art under 35 U.S.C. §
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`102(b)(pre-AIA). As shown in the table from Beta below, Beta discloses variable
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`bandwidth in units of 100 kHz (24 subcarriers) within an available bandwidth of 100
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`kHz, 200 kHz, 400 kHz, 800 kHz, or 1.6 MHz, which allows for “flexible” deployment
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`according to the table.
`
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`ERIC-1007, p. 176 and ERIC-1012 ¶ 70 (color annotation added). Each set of 24
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`
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`subcarriers constituting 100 kHz is a “group” of subcarriers as the term is used in the
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`claims of the ’431 patent. See ERIC-1012, ¶ 70.
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`Beta also discloses allocating a variable number of bandslots (and therefore
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`variable bandwidth). See ERIC-1007, p. 198 and ERIC-1012, ¶ 70. “The resources
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`(time and frequency) are allocated based on the type of services, operational
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`environment/scenarios) (i.e., give more flexibility).” ERIC-1007, p. 198. The modes of
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`“resource allocations” include n time slots + n band slots. EERIC-1007, p. 198. That
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`is, variable number of time slots and a variable number of bandslots (variable
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`bandwidth) can be used for resource allocation. See ERIC-1012, ¶ 70. Thus, a
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`variable number of bandslots may be allocated, each of which is 100 kHz, which allows
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`the bandwidth to vary in any of the available bandwidths of 200 kHz, 400 kHz, 800
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`kHz, and 1.6 MHz. See id.
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`Other prior art references described in detail in the challenges below disclose
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`properties of preamble sequences, that include good autocorrelation, crosscorrelation,
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`and low peak-to-average power ratio. These include:
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` U.S. Patent Publication No. 2002/0181509 (“Mody”) having a priority date of April
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`24, 2001 and a publication date of December 5, 2002, qualifies as prior art under 35
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`U.S.C. § 102(b)(pre-AIA).
`
` S. Nobilet, et al., “Spreading Sequences for Uplink and Downlink MC-CDMA
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`Systems:
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` PAPR and MAI Minimization”, European Transactions on
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`Communications, pp. 465-473, vol. 13, no. 5, September-October 2002 (“Nobilet”)
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`qualifies as prior art under 35 U.S.C. § 102(b)(pre-AIA); and
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` B. Popovic, “Spreading Sequences for Multicarrier CDMA Systems”, IEEE Trans.
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`Comm., pp. 918-926, vol. 47, no. 6, June 1999 (“Popovic”) qualifies as prior art
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`under 35 U.S.C. § 102(b)(pre-AIA).
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`V. Reasons That Challenges Are Not Cumulative
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`Challenges #1 and #2 are based on a first set of references including Zhuang, and
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`Challenges #3 and #4 are based on a second set of references that replaces Zhuang with
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`the combination of Mody, Nobilet, and Popovic. Petitioner respectfully submits that
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`these respective sets of challenges are not cumulative. Zhuang provides all the claimed
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`features of the preamble in a single reference but is prior art under 35 U.S.C. § 102(e)
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`that may be subject to a challenge from the patent owner. The second set of references,
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`on the other hand, replaces Zhuang with the combination of Mody, Nobilet, and
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`Popovic, each of which is prior art under 35 U.S.C. § 102(b) that cannot be sworn
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`behind. Therefore, Challenges #1 and #2, based on the first set of references including
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`Zhuang, and Challenges #3 and #4, based on the second set of references including
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`references Mody, Nobilet, and Popovic, are not cumulative. Thus, each set of
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`challenges should be included in the review of claims 1, 2, 8-12, and 18-22 of the ’431
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`patent.
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`VI.
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`Identification of Challenges and Claim Construction
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`A. Challenged Claims
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`Claims 1, 2, 8-12, and 18-22 of the ’431 patent are challenged in this petition.
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`Petition for Inter Partes Review of U.S. 7,787,431
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`B. Claim Construction
`This petition presents claim analysis in a manner that is consistent with the
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`broadest reasonable interpretation in light of the specification. See 37 C.F.R. §
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`42.100(b). For the sake of reference, claim terms will be identified in bold italics:
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`1.
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`Bandwidth
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`The ‘431 patent uses the term “bandwidth” in the abstract, the claims, and the
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`detailed description. However, the ‘431 patent does not set forth a special meaning for
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`the above term. As such, this term should be given its broadest reasonable
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`interpretation to one of ordinary skill in the art in view of the specification and the
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`term’s ordinary and accustomed meaning. See, e.g., ERIC-1012, ¶ 28. The ‘431 patent
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`uses the term “bandwidth” to refer to a frequency range a system occupies or uses. For
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`example, Fig. 6 of the ‘431 patent “illustrates the signal structure in the frequency
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`domain” for a specific embodiment. ERIC-1001, 4:36-37. “The variable channel
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`bandwidth is realized by adjusting the number of usable subcarriers, whose spacing is
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`set constant.” Id., 4:41-42. Fig. 6 illustrates various bandwidths (measured as a
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`frequency range, e.g., 5 MHz or 10 MHz) and numbers of subcarriers corresponding to
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`the bandwidth. See also, ERIC-1012, ¶ 28. Thus, under the broadest reasonable
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`interpretation in view of the ‘431 patent specification and the ordinary and accustomed
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`meaning, one of ordinary skill in the art would understand that “bandwidth” means a
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`frequency range that a component, circuit, or system passes or uses. ERIC-1013, p. 6
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`and ERIC-1012, ¶ 28.
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`2.
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`Core-Band
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`The ‘431 patent uses the term “core-band” in the claims and the detailed
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`description. The ‘431 patent sets forth a special meaning for core-band as follows: “[a]
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`core-band, substantially centered at the operating center frequency, is defined as a
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`frequency segment that is not greater than the smallest operating channel bandwidth
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`among all the possible spectral bands that the receiver is designed to operate with.”
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`ERIC-1001, 4:67-5:4 (emphasis added). Under the broadest reasonable interpretation
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`in view of the ‘431 patent specification one of ordinary skill in the art would understand
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`that “core-band” means a frequency segment that is not greater than the smallest
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`operating channel bandwidth among all the possible spectral bands that a receiver is
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`designed to operate with. ERIC-1012, ¶ 29.
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`3.
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`Primary Preamble
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`The ‘431 patent uses the term “primary preamble” in the claims and the detailed
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`description. Although the term “preamble” is a common term, the term “primary
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`preamble” is not known as a term of art in the field. See ERIC-1012, ¶ 30. Rather, the
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`‘431 patent uses the term in a special way. The term “preamble” denotes transmission
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`near the beginning of a transmission, such as a frame or slot. Id. For example, “[t]he
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`downlink transmission in each frame begins with a downlink preamble”, and
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`“[s]imilarly, uplink transmission can begin with an uplink preamble, which can be the
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`first or more of the OFDM symbols in the first uplink (UL) slot.” ERIC-1001, 3:51-52
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`and 56-58.
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`According to the ‘431 patent, the term “primary preamble” describes “a
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`preamble … designed to only occupy the CB [core band].” Id., 5:19-20. This feature
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`of the core-band also appears in various independent claims. For example, claim 1
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`states: “the primary preamble is a direct sequence in the time domain with a frequency
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`content confined within the core-band, or is an orthogonal frequency-divisional
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`multiplexing (OFDM) symbol corresponding to a particular frequency pattern within
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`the core-band” (emphasis added). Under the broadest reasonable interpretation in view
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`of the ‘431 patent specification one of ordinary skill in the art would understand that
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`“primary preamble” means a signal transmitted near the beginning of a transmission,
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`such as a frame or a time slot, and occupying only the core band. ERIC-1012, ¶ 31.
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`4.
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`Peak-to-Average Ratio
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`The ‘431 patent uses the term “peak-to-average ratio” in the claims and the
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`detailed description. The term “peak-to-average ratio,” without further clarification,
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`does not identify the metric or signal characteristic used to form the ratio. See ERIC-
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`1012, ¶ 32. This term, however, is understood as referring to a metric that is of general
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`concern in OFDM systems– that is, the peak to average power ratio. See id. A large
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`ratio of peak power to average power has disadvantages, such as “an increased
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`complexity of digital-to-analog converters and a reduced efficiency of the RF [radio
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`frequency] power amplifier.” See ERIC-1009, p. 3 and ERIC-1012, ¶ 32. Thus,
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`reduction of peak-to-average power has been studied extensively for OFDM systems.
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`See ERIC-1009, pp. 4-38 and ERIC-1012, ¶ 32. The term for the metric is shortened in
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`the ’431 patent from the more typical peak-to-average power ratio (see, e.g., id., p. 3;
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`See also, ERIC-1005, ¶ 47) to “peak-to-average ratio.” Under the broadest reasonable
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`interpretation in view of the ’431 patent specification and the ordinary and accustomed
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`meaning, one of ordinary skill in the art would understand that “peak-to-average ratio”
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`means peak-to-average power ratio. ERIC-1012, ¶ 32.
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`C. Statutory Grounds for Challenges
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`Challenge #1:
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`Claims 8-11 and 18-21 are unpatentable under 35 U.S.C. § 103(a) over Li,
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`Yamaura, and Zhuang.
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`Challenge # 2
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`Claims 1, 2, 12, and 22 are unpatentable under 35 U.S.C. § 103(a) over Li,
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`Yamaura, Zhuang, and Beta.
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`Challenge # 3
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`Claims 8-11 and 18-21 are unpatentable under 35 U.S.C. § 103(a) over Li,
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`Yamaura, Mody, Nobilet, and Popovic.
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`Challenge # 4
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`Claims 1, 2, 12, and 22 are unpatentable under 35 U.S.C. § 103(a) over Li,
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`Yamaura, Mody, Nobilet, Popovic, and Beta.
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`Petition for Inter Partes Review of U.S. 7,787,431
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`For the sake of cross-reference, the following analysis assigns reference
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`numbers, such as “8.0,” to refer to specific portions of the claims. The following
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`analysis explains how each claim limitation is met by the combined references.
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`Detailed factual support is provided in the included Expert Declaration, ERIC-1012
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`beginning at page 50.
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`1.
`Challenge #1: Claims 8-11 and 18-21 are unpatentable under
`3