PTAB

IPR2017-00106

Samsung Electronics Co Ltd v. Evolved Wireless LLC

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Method of Expanding a Code Sequence and Transmitting Data
  • Brief Description: The ’481 patent discloses methods and transmitters for transmitting a preamble sequence on a random access channel (RACH) in a mobile communication system. The invention centers on generating the preamble by repeating a specific base sequence a number of times to form a consecutive sequence, and then concatenating a single cyclic prefix (CP) to the front of that consecutive sequence before transmission.

3. Grounds for Unpatentability

Ground 1: Anticipation/Obviousness over Panasonic 792 - Claims 1-2 and 8-9 are invalid under 35 U.S.C. §102 or §103 over Panasonic 792.

  • Prior Art Relied Upon: Panasonic 792 (3GPP contribution document R1-060792).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Panasonic 792, a technical contribution to the 3GPP standards body, disclosed every element of the independent claims. Specifically, its Figure 1 depicted a RACH preamble structure consisting of a single cyclic prefix (“CP”) followed by “M Repetitions” of a CAZAC sequence. Petitioner contended this directly taught generating a preamble sequence by concatenating a single CP to a consecutive sequence formed by repeating a specific sequence (the CAZAC sequence) multiple times, as required by independent claims 1 and 8. The document further disclosed transmitting this preamble on a RACH. For dependent claims 2 and 9, Petitioner asserted that Panasonic 792’s explicit use of a “CAZAC sequence” met the limitation of generating the specific sequence from a Constant Amplitude Zero Auto Correlation (CAZAC) sequence.

Ground 2: Obviousness over Panasonic 792 and Panasonic 114 - Claims 3-4 and 10-11 are obvious over Panasonic 792 in view of Panasonic 114.

  • Prior Art Relied Upon: Panasonic 792 (3GPP document R1-060792) and Panasonic 114 (3GPP document R1-061114).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground built upon the preamble structure disclosed in Panasonic 792. Petitioner argued that Panasonic 114 taught modifying the CAZAC sequences of Panasonic 792 by “applying a cyclic shift,” as required by dependent claims 3 and 10. Panasonic 114 allegedly proposed using “cyclic-shifted Zadoff-Chu CAZAC as preamble sequence mainly” because it offered superior performance. For claims 4 and 11, Petitioner asserted that Panasonic 114’s disclosure of using integer indices of cyclic shift (e.g., “m=1to8”) met the limitation that the value of the applied cyclic shift is determined as an integer multiple of a predetermined circular shift unit.
    • Motivation to Combine: A POSITA would combine these references because they addressed the same problem—RACH preamble design—within the same narrow field (3GPP TSG RAN WG1). Both were submitted by Panasonic, and Panasonic 114 expressly cited Panasonic 792. The motivation stemmed from the clear performance benefits articulated in Panasonic 114 for using cyclic-shifted sequences, which would have prompted a POSITA to incorporate this improvement into the basic preamble structure taught by Panasonic 792 as a routine design choice.
    • Expectation of Success: A POSITA would have a high expectation of success, as the combination involved substituting a known, superior-performing sequence type into a known preamble structure, with predictable improvements in correlation properties.

Ground 3: Obviousness over Panasonic 792, Panasonic 114, and Chu - Claims 6 and 13 are obvious over Panasonic 792 and Panasonic 114 in view of Chu.

  • Prior Art Relied Upon: Panasonic 792, Panasonic 114, and Chu (a 1972 IEEE article titled "Polyphase Codes With Good Periodic Correlation Properties").
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground added Chu to the combination of Panasonic 792 and 114 to teach the specific implementation of the cyclic shift. While the Panasonic references taught the use of cyclic-shifted CAZAC sequences, Petitioner argued that Chu, the seminal paper that introduced the Zadoff-Chu sequence, taught how to apply the cyclic shift. Chu allegedly disclosed that cyclic shifts can be implemented by “multiplying said specific sequence by an exponential sequence,” which directly mapped to the limitations of claims 6 and 13.
    • Motivation to Combine: A POSITA, seeking to implement the cyclic-shifted Zadoff-Chu sequences taught by the Panasonic references, would have been logically and predictably led to consult Chu. Both Panasonic 792 and Panasonic 114 expressly cited Chu. Therefore, a POSITA would consult Chu to understand the fundamental mathematical properties of the sequence and the standard method for applying cyclic shifts, which Chu explicitly provided.
    • Expectation of Success: There was a clear expectation of success because the combination involved applying a fundamental, well-understood mathematical technique from a foundational paper (Chu) to implement a specific sequence type (cyclic-shifted CAZAC) proposed by the primary references for its known benefits.

4. Key Claim Construction Positions

  • “a consecutive sequence having a length (N*L)”: Petitioner argued that this term, based on arguments made during prosecution to overcome a prior art rejection (the Jung reference), must be construed as a sequence that is “entirely within one frame.” The applicant allegedly distinguished Jung by arguing its preamble sequence was not "consecutive" because it was split between multiple frames. Petitioner contended this argument created a clear disavowal of scope, limiting the claim term to a single-frame sequence.

5. Relief Requested

  • Petitioner requests institution of an IPR and cancellation of claims 1-4, 6, 8-11, and 13 of the ’481 patent as unpatentable.