Paper No. 8
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`UNITED STATES PATENT AND TRADEMARK OFFICE
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`
`
`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. 2018-01476
`U.S. Patent No. 7,764,711
`
`PATENT OWNER PRELIMINARY RESPONSE
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`IPR2018-01476
`U.S. Patent No. 7,764,711
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`TABLE OF CONTENTS
`Introduction ........................................................................................................................ 1
`I.
`II. Overview of the ’711 Patent ........................................................................................... 2
`III. Overview of Cited References ..................................................................................... 10
`A. U.S. Patent No. 6,067,209 to Paulraj et al. (“Paulraj”) (Ex. 1005) ...........11
`B. “Achieving High Data Rates in CDMA Systems Using BLAST
`Techniques” by Howard Huang, Harish Viswanathan, and G.J. Foschini
`(“Huang”) (Ex. 1006) ................................................................................14
`C. U.S. Patent No. 7,095,709 to Walton et al. (“Walton”) (Ex. 1008) ..........17
`D. U.S. Patent Application Publication No. 2002/0193146 to Wallace et al.
`(“Wallace”) (Ex. 1009) ..............................................................................18
`IV. Claim Construction ......................................................................................................... 21
`A. “specific data item” ....................................................................................21
`B. The Petition’s proposed construction for “user data requiring a better
`communication quality than other user data” improperly imports
`limitations from the specification into the claim. ......................................22
`V. Ground 1 fails because the Petition’s asserted references fail to disclose every
`element of the Challenged Claims and because the Petition fails to
`demonstrate a proper motivation to combine........................................................... 25
`A. Failure to Disclose Every Element of the Challenged Claims ..................25
`1. Paulraj fails to disclose or suggest “maps the plurality of data items to
`the at least one of the plurality of antennas such that the specific data
`item and the replica data item are transmitted from different antennas
`at a same time.” ...................................................................................26
`2. Walton fails to disclose or suggest “maps the plurality of data items to
`the at least one of the plurality of antennas such that the specific data
`item and the replica data item are transmitted from different antennas
`at a same time.” ...................................................................................28
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`IPR2018-01476
`U.S. Patent No. 7,764,711
`3. Huang fails to disclose or suggest “maps the plurality of data items to
`the at least one of the plurality of antennas such that the specific data
`item and the replica data item are transmitted from different antennas
`at a same time.” ...................................................................................30
`B. Lack of Motivation to Combine ................................................................31
`1. Petitioners have not shown and cannot show a motivation to combine
`Walton with Paulraj. ............................................................................31
`2. The Petition has not shown and cannot show a motivation to combine
`Huang with either Paulraj or Walton. .................................................36
`VI. Ground 2 fails based on an incorrect interpretation of the Challenged Claims.
`.............................................................................................................................................. 40
`VII. Conclusion ........................................................................................................................ 41
`WORD COUNT CERTIFICATION ................................................................................... 42
`CERTIFICATE OF SERVICE ............................................................................................. 43
`
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`IPR2018-01476
`U.S. Patent No. 7,764,711
`TABLE OF AUTHORITIES
`
` Page(s)
`
`Cases
`Broadcom Corp. v. Emulex Corp.,
`732 F.3d 1325 (Fed. Cir. 2013) .......................................................................... 32
`Douglas Dynamics, LLC v. Buyers Products Co.,
`717 F.3d 1336 (Fed. Cir. 2013) .......................................................................... 23
`Helmsderfer v. Bobrick Washroom Equip., Inc.,
`527 F.3d 1379 (Fed. Cir. 2008) .......................................................................... 23
`In re Katz Interactive Call Processing Patent Litig.,
`639 F.3d 1303 (Fed. Cir. 2011) .......................................................................... 23
`Kinetic Concepts, Inc. v. Smith & Nephew, Inc.,
`688 F.3d 1342 (Fed. Cir. 2012) .......................................................................... 33
`KSR Int’l Co. v. Teleflex Inc.,
`550 U.S. 398 (2007) ............................................................................................ 39
`Nidec Motor Corp. v. Zhongshan Broad Ocean Motor Co. Ltd.,
`868 F.3d 1013 (Fed. Cir. 2017) .......................................................................... 22
`Phillips v. AWH Corp.,
`415 F.3d 1303 (Fed. Cir. 2005) (en banc) .................................................... 21, 23
`Trivascular, Inc. v. Samuels,
`812 F.3d 1056, (Fed. Cir. 2016) ......................................................................... 36
`Wellman, Inc. v. Eastman Chem. Co.,
`642 F.3d 1355 (Fed. Cir. 2011) .......................................................................... 25
`Other Authorities
`37 C.F.R. § 42.65 ..................................................................................................... 34
`37 C.F.R. § 42.100(b) .............................................................................................. 21
`
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`IPR2018-01476
`U.S. Patent No. 7,764,711
`
`I.
`
`Introduction
`Patent Owner INVT SPE LLC (“INVT” or “Patent Owner”) respectfully
`
`submits this Preliminary Response to the Petition Seeking Inter Partes Review
`
`(“IPR”) of U.S. Patent No. 7,764,711 (the “’711 Patent”).
`
`The Board should deny institution because the Petition fails to establish a
`
`reasonable likelihood that any of claims 1−6 of the ’711 Patent (the “Challenged
`
`Claims”) are obvious in view of the Petition’s proposed combinations asserted in
`
`Ground 1: Paulraj in view of Huang, in further view of Walton (claims 1−6); and
`
`Ground 2: Wallace in view of Walton (claims 1−6).
`
`The Challenged Claims describe a multiple antenna transmission scheme
`
`employing two methods of wireless transmission—spatial multiplexing and
`
`transmit diversity—at the same time. Specifically, the Challenged Claims
`
`implement transmit diversity with respect to a specific data substream, which is
`
`designated as having a higher priority than other data items (see, e.g., Ex. 1001
`
`(’711 Patent) at 9) while, at a same time, implementing spatial multiplexing (i.e.,
`
`parallel transmission) with respect to the remaining data substreams.
`
`Implementation of transmit diversity for a specific data item at a same time
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`with spatial multiplexing of a data stream is missing from each of the references
`
`asserted in the Petition, and no combination of the asserted references discloses or
`
`
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`1
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`IPR2018-01476
`U.S. Patent No. 7,764,711
`suggests the claimed technique. Specifically, no asserted reference or combination
`
`of the asserted references discloses:
`
`maps the plurality of data items to the at least one of the
`plurality of antennas such that the specific data item and
`the replica data item are transmitted from different
`antennas at a same time
`
`Ex. 1001 (’711 Patent) at 11 (Claim 1) (emphasis added).
`
`Accordingly, Patent Owner respectfully submits that both Ground 1 and
`
`Ground 2 should be denied. Ground 1 fails to teach the requisite element, and
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`Ground 2 is expressly based on an (incorrect) interpretation of the challenged
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`claim which allows selectively switching “between spatial diversity and transmit
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`diversity, not one that implements them both at the same time.” Paper 1 at 44-45
`
`(emphasis added).
`
`For the reasons provided below, Patent Owner respectfully requests that the
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`Board deny institution.
`
`II. Overview of the ’711 Patent
`The ’711 Patent is directed to a multi-input/multi-output (“MIMO”) data
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`transmission scheme for data transmission between mobile devices and base
`
`stations in a multiple access environment. MIMO transmission involves different
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`items of data, such as, for example, a large volume data transmission that has been
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`IPR2018-01476
`U.S. Patent No. 7,764,711
`separated into a plurality of substreams that are transmitted from a plurality of
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`antennas on a transmitting side and received by at least the same number of
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`antennas on the receiving side. Ex. 1001 (’711 Patent) at 8.
`
`As discussed in detail below, the Challenged Claims relate to two methods
`
`of multiple-antenna transmission: transmit diversity and spatial multiplexing.
`
`Transmit diversity designates a specific data substream as having a higher priority
`
`than other data items (see, e.g., Ex. 1001 (’711 Patent) at 9). Spatial multiplexing,
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`on the other hand, allows parallel transmission of multiple data substreams.
`
`The Challenged Claims impose spatial multiplexing transmission and
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`transmit diversity at the same time. Specifically, the ’711 Patent describes a MIMO
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`data transmission scheme where a mobile device transmits a specific data item, as
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`well as a replica of the specific data item, from different antennas at the same time.
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`To that end, the Challenged Claims each recite a “mapping section [that] generates
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`a replica data item by replicating a specific data item of the plurality of data
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`items.” Ex. 1001 (’711 Patent) at 11 (Claim 1).
`
`Representative Claim 1 claims:
`
`1. A transmitting apparatus employing a MIMO (multi-
`input/multi-output) scheme of transmitting a plurality of
`data items for a same receiving apparatus using a plurality
`of antennas in parallel,
`the transmitting apparatus
`comprising:
`
`
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`3
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`IPR2018-01476
`U.S. Patent No. 7,764,711
`a mapping section that maps the plurality of data
`items to at least one of the plurality of antennas; and
`a transmitting section that transmits the plurality of
`data items using the at least one of the plurality of antennas
`to the receiving apparatus,
`wherein the mapping section generates a replica
`data item by replicating a specific data item of the plurality
`of data items, and maps the plurality of data items to the at
`least one of the plurality of antennas such that the specific
`data item and the replica data item are transmitted from
`different antennas at a same time.
`
`Ex. 1001 (’711 Patent) at 11 (Claim 1).
`
`Spatial Multiplexing
`
`The ’711 Patent’s Figure 4 shows an exemplary data transmission where
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`data 1 (directed to user 1 – user N) and data 2 (directed to user 1 – user N) are
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`transmitted simultaneously at a first transmission timing using the first
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`transmission system (antenna 1) and second transmission system (antenna 2). Ex.
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`1001 (’711 Patent) at 9. As shown, Figure 4 illustrates the invention of the
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`Challenged Claims such as, for example, each antenna transmitting different data
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`items in parallel to improve transmission capacity compared to single-antenna
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`techniques.
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`IPR2018-01476
`U.S. Patent No. 7,764,711
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`
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`This is generally known as spatial multiplexing. Ex. 1005 (Paulraj) at 35 (“Spatial
`
`multiplexing (SM) is a transmission technology which exploits multiple antennas
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`at both the base station(s) and at the subscriber units to increase the bit rate in a
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`wireless radio link . . . .”). Spatial multiplexing can be implemented to take
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`advantage of space, time, frequency, and codes. See, e.g., Ex. 1005 (Paulraj) at
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`34−35.
`
`Transmit Diversity
`
`Unlike spatial multiplexing, transmit diversity techniques are not concerned
`
`with increasing bit rate or improving transmission capacity compared to single-
`
`antenna techniques. Instead, transmit diversity techniques are focused on error
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`correction, reliability, and “improv[ing] the reliability of data transmission.” Ex.
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`U.S. Patent No. 7,764,711
`1008 (Walton) at 13. Using transmit diversity, “[e]ach diversity transmission mode
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`redundantly transmits data over time, frequency, space, or a combination thereof.”
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`Id. The purpose of redundant transmissions is to “improve the likelihood of correct
`
`reception by the receiver.” Id. For example:
`
`The basic idea of diversity receptions [sic] is that, if two
`or more independent samples of a signal are taken, these
`samples will fade in an uncorrelated manner. This means
`that
`the probability of all
`the
`samples being
`simultaneously below a given level is much lower than the
`probability of any individual sample being below that
`level.
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`Ex. 1009 (Wallace) at 23.
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`Simultaneous Transmission of Spatial Multiplexing and Transmit Diversity
`
`The Challenged Claims take advantage of spatial multiplexing by “using a
`
`plurality of antennas in parallel.” Yet, notably, the Challenged Claims also take
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`advantage of transmit diversity by transmitting a replica data item of a specific
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`data item “such that the specific data item and the replica data item are transmitted
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`from different antennas at a same time.” Ex. 1001 (’711 Patent) at 11.
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`Before the invention of the Challenged Claims, prior approaches to MIMO
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`transmission exploited multiple antenna transmission by either providing for error
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`correction and resending transmissions redundantly, i.e., same data sent again, in
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`IPR2018-01476
`U.S. Patent No. 7,764,711
`either time, frequency, or space; or providing for increased data transfer speed by
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`sending multiple data items in parallel to a receiver.
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`Indiscriminate transmit diversity, however, reduces data transfer speed and
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`transmission efficiency of the system because “the same data” is retransmitted, or
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`“assigned” to a given number of the available antennas in the MIMO system,
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`regardless of whether any error actually occurred. Ex. 1001 (’711 Patent) at 7,
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`Fig. 5. When data is retransmitted unnecessarily, the resources used for the
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`retransmission are wasted. Ex. 1001 (’711 Patent) at 1:60-6 (stating that in such
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`systems, “the data transmission deteriorates”).
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`In other words, at the time of the invention of the Challenged Claims, it was
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`understood that “maximizing one type of gain” through using either spatial
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`multiplexing or transmit diversity “may not necessarily maximize the other.” Ex.
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`1013 (Zheng) at 2. Consequently, it was known that higher spatial multiplexing
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`(i.e., higher transmission capacity) would come at the price of sacrificing transmit
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`diversity (i.e., risking transmission error). Ex. 1013 (Zheng) at 3. There was a
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`recognized tradeoff in signal quality and transmission speed, or efficiency.
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`To solve this “tradeoff” problem, prior approaches implemented “switching”
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`techniques that would “switch between the two modes, depending on the
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`instantaneous channel condition.” Ex. 1013 (Zheng) at 2. Studies taken around the
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`time of the ’711 Patent sought to identify an “optimal tradeoff,” which was
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`IPR2018-01476
`U.S. Patent No. 7,764,711
`described as “bridg[ing] the gap” between the maximum diversity gain and the
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`maximum spatial multiplexing gain.1 The studies found that “optimal tradeoffs”
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`can be “useful for evaluating and comparing existing schemes,” but concluded that
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`gains in error rates of spatially separate transmissions of substreams could only be
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`achieved by reducing the maximum spatial multiplexing gains of the system. Ex.
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`1013 at 24.
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`The ’711 Patent takes a different approach. The ’711 Patent solves the
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`“tradeoff” problem by employing diversity transmission to a specific data
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`substream, which is designated as having a higher priority than other data items.
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`See, e.g., Ex. 1001 (’711 Patent) at 9. This specific data item is replicated for
`
`transmission simultaneously on different antennas, while the remaining data
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`
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` 1
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` The cited references can only represent these gains as approximations based on a
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`number of assumptions about the transmission environments. For example, the
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`Petition’s Exhibit 1013 represents the spatial multiplexing gains as merely scaling
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`according to rlogSNR (where r = SM gain) and the diversity gain as decaying
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`according to 1/SNRd (where d = diversity gain). Ex. 1013 at 3, 5, 24. These
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`approximations cannot be incorporated into practical, i.e., real-world, applications.
`
`Ex. 1006 (Huang) at 42 (“It remains for future work to study the effect of non-
`
`idealities that occur in practical systems . . . .”).
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`IPR2018-01476
`U.S. Patent No. 7,764,711
`substreams can be transmitted in parallel without replication. See, e.g., id. This is
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`evidenced by the ’711 Patent’s Figure 4, which shows both techniques being used
`
`at a same time (on the X-axis):
`
`
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`In this regard, the ’711 Patent describes “recogniz[ing] the type of data
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`included in the transmission signal based on the channel quality and moving speed
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`of the receiving side,” whereby the recognizing “gives higher priority in
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`transmission (hereinafter referred to as ‘specific data’) from other data.” Ex. 1001
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`(’711 Patent) at 3:36-41. Because this higher priority “specific data” is modulated
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`using a different spreading code than that of replica data, the invention of the ’711
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`Patent “improve[s] the reception performance on the receiving side for specific
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`data while maintaining the transmission efficiency of the communication system.”
`
`Ex. 1001, ’711 Patent at 4:4-30, 5:26-28.
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`IPR2018-01476
`U.S. Patent No. 7,764,711
`Even the Petition recognizes that the ’711 Patent describes the
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`“simultaneous implementation of spatial multiplexing (transmitting different data
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`streams from different antennas) and transmit diversity (transmitting the same data
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`from different antennas).” 2 Paper 1 at 44 (citing Ex. 1001 at 1:60-2:12, 4:36-5:3,
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`5:13-25, and Figures 3-4). However, the references asserted in the Petition fail to
`
`show such simultaneity.
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`III. Overview of Cited References
`The Petition presents two combinations of references in Grounds 1 and 2,
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`which rely on four references:
`
`
`
` 2
`
` To clarify, the ’711 Patent specifies transmission of different code division
`
`multiplexed signals from a plurality of transmission antennas by apportioning
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`specific data to a plurality of antennas and spreading/modulating the specific data
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`with different spreading codes assigned thereto before being transmitted. Ex. 1001
`
`at 2:7-12. In other words, the transmission data is apportioned substantially equally
`
`across the multiple antennas to improve efficiency or, if the transmission data is a
`
`specific data item, it is replicated and the specific data item and replica data item
`
`are apportioned so as to be transmitted on separate transmission antennas. Ex. 1001
`
`at 4:11-24.
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`10
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`IPR2018-01476
`U.S. Patent No. 7,764,711
`1. U.S. Patent No. 6,067,209 to Paulraj et al. (“Paulraj”) (Ex. 1005);
`2. “Achieving High Data Rates in CDMA Systems Using BLAST
`Techniques” by Howard Huang, Harish Viswanathan, and G.J.
`Foschini (“Huang”) (Ex. 1006);
`3. U.S. Patent No. 7,095,709 to Walton et al. (“Walton”) (Ex. 1008); and
`4. U.S. Patent Application Publication No. 2002/0193146 to Wallace et
`al. (“Wallace”) (Ex. 1009).
`
`Ground 1 is based on an interpretation of the Challenged Claims as
`
`describing “simultaneous implementation of spatial multiplexing (transmitting
`
`different data streams from different antennas) and transmit diversity (transmitting
`
`the same data from different antennas).” Paper 1 at 44. Ground 2 is based,
`
`mistakenly, on an interpretation of the Challenged Claims as describing “a MIMO
`
`system that selectively switches between spatial diversity and transmit diversity,
`
`not one that implements them both at the same time.”
`
`A. U.S. Patent No. 6,067,209 to Paulraj et al. (“Paulraj”) (Ex. 1005)
`The Petition’s Ground 1 primary reference, Paulraj, describes implementing
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`“spatial multiplexing in conjunction with one or more multiple access protocols in
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`a wireless network.” Ex. 1005 Abstract. Paulraj focused on the problem of
`
`improving data transfer speed in multiple access environments. Ex. 1005 at 33
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`(“What is needed is a way to improve data transfer speed in the multiple access
`
`environments currently utilized for wireless communications within the constraints
`
`of available bandwidth.”).
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`IPR2018-01476
`U.S. Patent No. 7,764,711
`The invention of Paulraj focuses on spatial multiplexing only to increase
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`data transfer speed. While transmit diversity is also mentioned, there is not even a
`
`suggestion to implement it at the same time using replicas of one or more
`
`transmitted spatial multiplexing streams, let alone an explanation as to how a
`
`person having ordinary skill in the art would do so. Ex. 1005 at 6:7-13 and 2:62-
`
`13:1.
`
`According to the disclosure of Paulraj, “[w]hen a subscriber unit is first
`
`turned on, it performs a series of startup procedures and then samples the received
`
`signal strength on all user channels.” Ex. 1005 at 8:31-33. In this way, the
`
`subscriber unit of Paulraj can tune to the channel with the strongest receive
`
`strength and synchronize with the BTS(s). Ex. 1005 at 8:34-36. Paulraj proposes
`
`continually monitoring channel conditions to tune to the “best” receive frequency
`
`channel and mitigate against transmission errors. Ex. 1005 at 8:36-39 (“The
`
`subscriber unit interprets the data and continues monitoring the controlled
`
`channels. The subscriber unit automatically re-scans periodically to ensure that it is
`
`using the best control channel.”).
`
`Notably, Paulraj does not disclose replicating a specific data item of the
`
`plurality of data items, and mapping the plurality of data items to at least one of a
`
`plurality of antennas such that the specific data item and the replica data item are
`
`transmitted from different antennas at the same time. Instead, the transmission
`
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`IPR2018-01476
`U.S. Patent No. 7,764,711
`scheme of Paulraj employs a “detector 400,” which “determines that the
`
`datastream(s) 454-456 require spatial processing.” Ex. 1005, 20:15-16. In other
`
`words, Paulraj describes a “mode detection” whereby “[d]atastream(s) might, as
`
`discussed, be categorized as traditional vs. spatial, or on the basis of QoS or bit rate
`
`requirement.” Ex. 1005 at 16:66-17:4.
`
`Although Paulraj briefly makes reference to “a number of well-known prior
`
`art signal processing techniques [that] may be implemented to improve the quality
`
`of transmission,” “including, but not limited to diversity processing,” Paulraj
`
`contains no disclosure concerning or suggesting simultaneous implementation of
`
`spatial multiplexing and transmit diversity such that diversity is implemented by
`
`transmitting a replica of one or more of transmitted spatial streams. Ex. 1005 at
`
`6:7-13 and 12:62-13:1. And although Paulraj mentions “if diversity processing is
`
`implemented,” Paulraj contains no disclosure of how “diversity processing” is
`
`implemented. Ex. 1005, 13:5-9 (emphasis added). Indeed, Paulraj notes that its
`
`multiple antennas can be utilized “either for spatial multiplexing or to implement
`
`receive/transmit processing, e.g. diversity techniques . . . .” Id. at 12:6-8 (emphasis
`
`added). Paulraj simply does not disclose use of both spatial multiplexing and
`
`transmit diversity at the same time, nor does it disclose the use of both in the
`
`particular manner taught in the ’711 patent.
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`IPR2018-01476
`U.S. Patent No. 7,764,711
`“Achieving High Data Rates in CDMA Systems Using BLAST
`B.
`Techniques” by Howard Huang, Harish Viswanathan, and G.J.
`Foschini (“Huang”) (Ex. 1006)
`The Petition’s Ground 1 reference, Huang, is a conference paper that
`
`describes allocating resources such as preading codes, antennas, and power
`
`“efficiently among K high-speed data users” in a downlink system under idealized
`
`conditions, and plots the resulting spectral efficiencies. Ex. 1006 at 38, Fig. 4.
`
`Huang provides only a narrow discussion focused on a demonstration of
`
`“potential for significant capacity gains from using multiple transmit and receive
`
`antennas in CDMA systems, [where] the results were based on assumptions such a
`
`perfect power control, perfect channel estimation and complex processing at the
`
`receiver.” Ex. 1006 at 42. Huang admits that “it remains for future work to study
`
`the effect of non-idealities that occur in practical systems and to consider channel
`
`coding to achieve significant fractions of the potential capacity gains.” Ex. 1006 at
`
`42. Because Huang provides no specificity regarding how its disclosure could be
`
`used in systems contemplating “non-idealities,” it follows that Huang is intended
`
`for discussion and academic purposes.
`
`Huang does not disclose transmitting spatial multiplexing and transmit
`
`diversity simultaneously. Huang “studied a high-speed downlink CDMA system
`
`which uses multiple antenna transmit diversity, multicode transmission, and space-
`
`time detectors” and developed and used “a novel technique for evaluating the
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`IPR2018-01476
`U.S. Patent No. 7,764,711
`system capacity.” Ex. 1006 at 42. Huang shows four, idealized transmission
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`configurations via simple diagrams:
`
`Notably, the results of Huang’s study “were based on assumptions such as
`
`perfect power control, perfect channel estimation and complex processing at the
`
`receiver.” Ex. 1006 at 42 (emphasis added). Accordingly, Huang is focused on
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`IPR2018-01476
`U.S. Patent No. 7,764,711
`“evaluat[ing] the capacity of a downlink cellular CDMA system where the
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`transmitters use multiple antennas and the receivers use space-time multiuser
`
`detection.” Ex. 1006 at 38 (emphasis added).
`
`The majority of Huang is devoted to explaining the assumptions underlying
`
`the study and the calculation of spectral efficiency for four transmission
`
`configurations, where capacity is determined “in terms of the number of users per
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`sector the system can support” and “spectral efficiency is given by the total data
`
`throughput per sector divided by the bandwidth.” Ex. 1006 at 40.
`
`None of the four transmission configurations discloses implementing
`
`transmit diversity for a specific data item at a same time with spatial multiplexing
`
`of a data stream. Specifically, Huang’s discussion of “multicode” or “different-
`
`code” transmission and “transmit diversity” for a given number of transmit
`
`antennas does not, on its face, “map[] the plurality of data items to the at least one
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`of the plurality of antennas such that the specific data item and the replica data
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`item are transmitted from different antennas at a same time.” See, e.g., id. at Figure
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`1A-D.
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`Further, Huang ultimately recommends not using simultaneous spatial
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`multiplexing and transmit diversity—concluding that transmit diversity should
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`ideally be implemented in a multiuser downlink transmission system where there
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`are few receive antennas, and should not be used when there is a large number of
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`U.S. Patent No. 7,764,711
`receive antennas. Ex. 1006 at 41. Huang bases this conclusion on a finding that
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`“while both different code transmission and transmit diversity improve the link
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`performance, the tradeoff is a lower achievable spectral efficiency.” Id. (emphasis
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`added). Indeed, to achieve high spatial multiplexing gains (high P), Huang
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`recommends “conserving codes with same-code transmission and less transmit
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`diversity.” Ex. 1006 at 42 (emphasis added).
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`C. U.S. Patent No. 7,095,709 to Walton et al. (“Walton”) (Ex. 1008)
`The Petition’s Ground 1 reference, Walton, describes “using a number of
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`diversity transmission modes depending on the capability of the receiver device
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`and the channel conditions.” Ex. 1008 at 2:17-20. Like the Petition’s other
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`references, Walton does not disclose the simultaneous use of spatial multiplexing
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`and transmit diversity in a MIMO transmission scheme.
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`Walton focuses on “diversity transmission modes [that] attempt to achieve
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`transmit diversity by establishing orthogonality among the multiple transmit
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`antennas.” Ex. 1008 at 2:31-34. Walton is not focused on spatial multiplexing. In
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`the instances where spatial multiplexing is briefly referenced, Walton states
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`generally that “[t]he transmission modes may also include spatial multiplexing
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`transmission modes and beam steering transmission modes, which may be used to
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`achieve higher bit rates under certain favorable channel conditions.” Ex. 1008 at
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`2:36-39; 9:63-65. Walton’s vague statements regarding transmission modes cannot
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`U.S. Patent No. 7,764,711
`be equated with implementation of transmit diversity for a specific data item at a
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`same time with spatial multiplexing of a data stream.
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`Where special multiplexing is mentioned, Walton describes switching
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`between diversity transmission and spatial multiplexing, the prior art upon which
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`the’711 Patent aimed to improve. Ex. 1008, 19:61-66 (describing that the diversity
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`transmission modes may be “fixed or dynamically selected”). Although Walton
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`provides that “one diversity transmission mode may be used for all data-carrying
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`subbands, or a separate diversity transmission mode may be selected for each data-
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`carrying subband” or “for a given subband, it may be possible to use different
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`diversity transmission modes for different sets of transmit antennas,” Walton
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`contains no disclosure or support for implementation of transmit diversity for a
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`specific data item at a same time with spatial multiplexing of a data stream. Ex.
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`1008 at 20:3-11.
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`D. U.S. Patent Application Publication No. 2002/0193146 to Wallace
`et al. (“Wallace”) (Ex. 1009)
`The Petition’s Ground 2 primary reference, Wallace, describes the use of
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`“antenna diversity” to support “mixed mode (i.e., one transmitter communicating
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`with a MIMO and/or MISO user and also with a SISO user).” Ex. 1009 at [0041].
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`Petitioners allege that Wallace was publicly available as of December 19, 2002.
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`Paper 1 at 44. Wallace, however, does not disclose implementing transmit diversity
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`for a specific data item at a same time with spatial multiplexing of a data stream.
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`Rather, Wallace describes selecting either spatial diversity or transmit diversity,
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`and does not suggest implementing both spatial multiplexing and transmit diversity
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`at the same time.
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`Wallace describes handling mixed mode transmission by determining an
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`“appropriate transmission scenario.” See, e.g., Ex. 1009 at [0105], [0106], [0110],
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`[0123], [0125], [0126]. Wallace proposes the use of a base station to “determine[]
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`the configuration and requirements of each communication link.” Ex. 1009 at
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`[0121]. For example, the base stations of Walton determine whether “the mobile
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`station has multiple receive antennas,” and if it does “[p]rocessing then continues
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`to step 418 to determine the particular model capability of the receiver, i.e., spatial
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`diversity or pure diversity.” Ex. 1009 at [0105]. In this way, Wallace describes
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`selecting either spatial diversity or transmit diversity. For example, Wallace
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`explains “[i]f the link quality is good, spatial diversity is used, else pure diversity is
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`applied.” Ex. 1009 at [0106]. Wallace further suggests that the base station should
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`perform “the methods 400 and 500 of FIGS. 13 and 14, respectively,” i.e., either
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`“pure diversity” or “spatial diversity.” Ex. 1009 at [0125]; Figures 13 and 14
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`(Figure 13 reproduced below, annotated):
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`
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`To accomplish switching between spatial diversity or transmit diversity,
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`Wallace describes requiring or requesting “information regarding the configuration
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`and operating mode of each communication link,” or “information regarding the
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`channel quality of a given link” to “determin[e] the appropriate configuration and
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`p