PTAB

IPR2025-00792

Samsung Electronics Co Ltd v. GenghisComm Holdings LLC

Log In
Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Communication in Wireless Networks
  • Brief Description: The ’285 patent describes methods and apparatuses for communication in an Orthogonal Frequency Division Multiplexing (OFDM) wireless network. The technology involves encoding data symbols with complex-valued polyphase codes to produce subcarrier values, which are then modulated onto OFDM subcarriers to generate a time-domain waveform with a controlled, low peak-to-average power ratio (PAPR).

3. Grounds for Unpatentability

Ground 1: Anticipation/Obviousness over Galda - Claims 1, 2, 6, 7, and 10 are anticipated by or obvious over Galda.

  • Prior Art Relied Upon: Galda (Dirk Galda & Hermann Rohling, A Low Complexity Transmitter Structure for OFDM-FDMA Uplink Systems, IEEE 55th Vehicular Technology Conference, May 6, 2002).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Galda, a 2002 conference paper, teaches every element of the independent method claim 1. Galda describes an OFDM-FDMA uplink system for a mobile terminal that uses a Discrete Fourier Transform (DFT) spreading matrix to reduce PAPR. Petitioner asserted this DFT matrix constitutes the claimed "set of complex-valued codes." Galda's system was shown to perform the claimed steps of encoding data symbols to produce subcarrier values, modulating these values onto assigned OFDM subcarriers using an IFFT, and producing a time-domain waveform. Crucially, Petitioner argued that Galda’s use of DFT spreading with equidistant subcarrier allocation results in a "periodic repetition of the complex user data symbol sequence," which inherently produces the claimed first and second periodic pulse waveforms centered at different times within the OFDM symbol.
    • Key Aspects: This ground formed the foundation for all other challenges, establishing that the core inventive concept was disclosed in a single prior art reference.

Ground 2: Obviousness over Galda and Dowling - Claims 11, 12, 16, 17, 20-22, 26, 27, and 30 are obvious over Galda in view of Dowling.

  • Prior Art Relied Upon: Galda, and Dowling (Patent 6,597,745).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground addressed the apparatus and computer-program product claims, which require implementation on a processor with non-transitory memory. Petitioner contended that while Galda describes the signal processing method, it does not specify hardware or software implementation. Dowling was introduced as teaching that OFDM transmitter functions, including modulation, can be implemented as software modules executing on a programmable processor.
    • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine Galda's method with Dowling’s implementation architecture to achieve the known benefits of software-defined radios, such as design flexibility and ease of updating. Petitioner argued this was a simple substitution of a known software-based transmitter for a hardware-based one to perform the same functions taught by Galda.
    • Expectation of Success: A POSITA would have a high expectation of success, as implementing defined mathematical operations like those in Galda on a general-purpose processor was a routine and well-understood practice in the field of digital signal processing.

Ground 3: Obviousness over Galda and Doufexi - Claim 9 is obvious over Galda in view of Doufexi.

  • Prior Art Relied Upon: Galda, and Doufexi (Angela Doufexi, et al., Design Considerations and Initial Physical Layer Performance Results for a Space Time Coded OFDM 4G Cellular Network, IEEE International Symposium, Sept. 18, 2002).

  • Core Argument for this Ground:

    • Prior Art Mapping: This ground addressed dependent claim 9, which adds the limitation of "selecting one of a set of subcarrier frequency spacings." Petitioner argued that Galda's system, while teaching modulation onto subcarriers, does not explicitly disclose using a selectable set of different spacings. Doufexi was introduced to remedy this, as it explicitly proposes an OFDM system for 4G cellular standards with multiple, selectable subcarrier spacings (e.g., 16 kHz and 8 kHz).
    • Motivation to Combine: Doufexi provides the express motivation, explaining that since 4G systems will be deployed in a wide range of environments, a fixed set of parameters is incapable of achieving high performance in all cases. A POSITA would therefore have been motivated to modify Galda’s system with the selectable subcarrier spacings taught by Doufexi to improve performance and adaptability.
    • Expectation of Success: A POSITA would expect success in this combination because adjusting OFDM parameters like subcarrier spacing to optimize performance for different channel conditions was a known design technique with predictable outcomes.

  • Additional Grounds: Petitioner asserted additional obviousness challenges based on similar combinations. Obviousness of claims 19 and 29 was argued over Galda, Dowling, and Doufexi. Alternative grounds for claims 9, 19, and 29 were also asserted, replacing Doufexi with either Lucent (a 2002 3GPP contribution) or Ma (Application # 2015/0256308), both of which also taught using variable subcarrier spacings to enhance system performance.

4. Key Technical Contentions (Beyond Claim Construction)

  • Effective Filing Date: Petitioner contended that the ’285 patent is not entitled to its claimed priority date going back to 2004, but instead has an effective filing date of November 26, 2020. This argument was based on the assertion that the specification was substantially amended late in prosecution to add new matter describing a single-user device system, which diverges from the "cooperative networking" among multiple terminals that was the focus of the parent applications. If this argument prevails, the patent would be governed by post-AIA law, making references like Ma available as prior art.

5. Arguments Regarding Discretionary Denial

  • Petitioner argued that discretionary denial under §314(a) based on the Fintiv factors would be inappropriate. The petition asserted that: (1) Petitioner will seek a stay of the parallel district court proceeding; (2) the district court trial is scheduled for April 2026, likely after a Final Written Decision (FWD) would issue; (3) investment in the parallel litigation is minimal as the case is in its early stages; (4) Petitioner stipulated that it would not pursue in court any grounds raised or that could have been reasonably raised in the IPR; and (5) the strong merits of the petition, based on prior art not considered by the Examiner, weigh heavily in favor of institution.

6. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1, 2, 6, 7, 9-12, 16, 17, 19-22, 26, 27, 29, and 30 of the ’285 patent as unpatentable.