PTAB

IPR2025-00793

Samsung Electronics Co Ltd v. GenghisComm Holdings LLC

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Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Flexible Channel Bandwidth for Mobile Communications
  • Brief Description: The ’792 patent describes methods for enabling flexible channel bandwidth in Orthogonal Frequency Division Multiplexing (OFDM) mobile communications. The technology involves provisioning OFDM subcarriers and using polyphase codes derived from a discrete Fourier transform (DFT) to encode data symbols, creating a superposition signal that resembles a single-carrier signal to reduce peak-to-average power, and adapting parameters like subcarrier spacing.

3. Grounds for Unpatentability

Ground 1: Claims 1, 3, 5, 8, 10, 12, 15, 17, and 19 are anticipated by or obvious over Shattil-257.

  • Prior Art Relied Upon: Shattil-257 (Patent 7,430,257).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Shattil-257 discloses all limitations of the challenged claims. Shattil-257 teaches a "scalable CI modulation system" applicable to OFDM that enables flexible bandwidth by dynamically allocating channel resources. It discloses provisioning OFDM subcarriers through "Carrier Selection" by control circuitry, encoding data symbols with polyphase codes derived from a Fourier transform, and using an IFFT to modulate these symbols onto subcarriers, thereby creating a superposition signal. Petitioner contended that Shattil-257’s teaching of selectable "Carrier Spacing" inherently discloses selecting one of a plurality of subcarrier spacings, which corresponds to selecting one of a plurality of symbol durations due to their inverse relationship.
    • Key Aspects: The argument relies on Shattil-257's disclosure of a highly adaptable communication system where control circuitry adjusts signal parameters, including carrier spacing and the number of carriers, to meet system requirements.

Ground 2: Claims 1-3 and 5 are obvious over Galda in view of Lucent.

  • Prior Art Relied Upon: Galda (a 2002 conference paper) and Lucent (a 2002 3GPP technical contribution).

  • Core Argument for this Ground:

    • Prior Art Mapping: Petitioner asserted that Galda teaches a low-complexity OFDM-FDMA transmitter that uses DFT spreading to reduce peak-to-average power ratio, resulting in a signal "identical to a single carrier transmission." Galda discloses provisioning OFDM subcarriers for different users, encoding data symbols using a DFT-based spreading matrix, and modulating them via an IFFT to create a superposition signal. While Galda provides flexibility, it does not explicitly teach selecting from multiple different subcarrier spacings. Lucent remedies this by proposing a baseline OFDM system with three distinct configurations for different deployment environments (e.g., vehicular, pedestrian), each with a specific subcarrier spacing (4.8 kHz, 9.6 kHz, and 19.2 kHz).
    • Motivation to Combine: A POSITA would combine Galda’s efficient DFT-spread OFDM system with Lucent’s technique of using pre-defined configurations of subcarrier spacings. The motivation would be to improve Galda's system by making it adaptable to a wide range of operating environments—a known problem with a known solution, as taught by Lucent. This combination would enhance system performance and flexibility without undue experimentation.
    • Expectation of Success: A POSITA would have a reasonable expectation of success because combining the references involves applying a known technique (using multiple, predefined parameter sets for different environments) to improve a known system (a DFT-spread OFDM transmitter) to achieve predictable results (enhanced adaptability and performance).

  • Additional Grounds: Petitioner asserted additional obviousness challenges, including that claims 2, 9, and 16 are obvious over Shattil-257 in view of Lucent, arguing a POSITA would have been motivated to implement Lucent's specific power-of-two scaled subcarrier spacings into Shattil-257’s generally scalable framework. Further grounds argued claims 8-10, 12, and 15-19 are obvious over combinations of Galda, Lucent, Doufexi (a 2002 symposium paper), and Dowling (Patent 6,597,745), primarily adding Dowling's teachings on software implementation to satisfy the apparatus and computer-readable media limitations.

4. Key Technical Contentions (Beyond Claim Construction)

  • Effective Filing Date: A central contention is that the ’792 patent is not entitled to its claimed 2007 priority date. Petitioner argued there is a break in the continuity of disclosure because an intermediate application in the priority chain (the ’984 application) is directed to a different invention ("Method and Apparatus for Fast Prototyping of Wireless Transceivers") and fails to provide written description support for the claims of the ’792 patent. This break allegedly renders the patent’s effective filing date no earlier than June 8, 2015, making references like Shattil-257 (issued 2008) valid prior art under the AIA.

5. Arguments Regarding Discretionary Denial

  • Petitioner argued that discretionary denial under Fintiv would be inappropriate. Key reasons included that Petitioner will seek a stay of the co-pending district court litigation, the trial date (April 2026) is close to or after the projected date for a Final Written Decision (FWD), and investment in the parallel proceeding is minimal as it is in the early stages. Petitioner also offered a stipulation not to pursue in district court any ground raised or that reasonably could have been raised in the IPR. Finally, Petitioner argued the merits are strong and denial under §325(d) is unwarranted because the asserted prior art was never considered during prosecution.

6. Relief Requested

  • Petitioner requests institution of an inter partes review (IPR) and cancellation of claims 1-3, 5, 8-10, 12, 15-17, and 19 of the ’792 patent as unpatentable.