PTAB

IPR2025-01043

Samsung Electronics Co Ltd v. Wilus Institute Of Standards Technology Inc

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: WIRELESS COMMUNICATION METHOD USING ENHANCED DISTRIBUTED CHANNEL ACCESS, AND WIRELESS COMMUNICATION TERMINAL USING SAME
  • Brief Description: The ’035 patent is directed to a wireless communication terminal that dynamically adapts its channel access behavior to improve efficiency in scenarios involving both contention-based channel access and scheduled multi-user uplink (UL-MU) transmissions.

3. Grounds for Unpatentability

Ground 1: Obviousness over Zhou, Cherian, and Kim - Claims 1-3 and 8-10 are obvious over Zhou in view of Cherian and Kim.

  • Prior Art Relied Upon: Zhou (Application # 2017/0202023), Cherian (Application # 2017/0325264), and Kim (Application # 2018/0034595).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that the combination teaches all limitations of independent claims 1 and 8. Zhou was asserted to teach a system where an access point (AP) selects different Enhanced Distributed Channel Access (EDCA) parameters for stations (STAs) based on their capability for UL-MU transmissions. Cherian was argued to teach switching between a first parameter set (for single-user mode) and a second parameter set (for multi-user mode) upon receiving a trigger frame from an AP, and using an EDCA timer to control the duration of the MU mode. Kim was asserted to disclose different acknowledgement (ACK) policies, including options for an MPDU to request an immediate response or not request one. Petitioner contended the combination renders obvious setting the MU EDCA timer either (a) when the transmission of a trigger-based PPDU ends, if no immediate response is requested, or (b) upon receipt of an immediate response (e.g., an ACK), if one is requested. These limitations correspond to amendments made during prosecution to overcome prior art.
    • Motivation to Combine: A POSITA would combine these references to optimize wireless network performance in environments supporting both single-user and multi-user operations. Petitioner argued it would have been logical to integrate Zhou’s parameter selection with Cherian’s mode-transition timing and Kim’s well-known ACK policies to create a more robust and reliable system, addressing a known need for efficient channel utilization and data delivery.
    • Expectation of Success: A POSITA would have a reasonable expectation of success, as the combination involves integrating known, predictable solutions (parameter sets, timers, ACK protocols) to solve a recognized problem of managing transitions between communication modes.

Ground 2: Obviousness over Zhou, Cherian, Kim, and Ho - Claims 4-5 are obvious over Zhou, Cherian, and Kim in view of Ho.

  • Prior Art Relied Upon: Zhou (Application # 2017/0202023), Cherian (Application # 2017/0325264), Kim (Application # 2018/0034595), and Ho (Application # 2010/0195664).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground builds on the base combination of Zhou-Cherian-Kim and adds Ho to address the limitations of claims 4 and 5, which relate to backoff procedures using a contention window (CW). Petitioner argued Ho explicitly teaches a backoff mechanism where a processor calculates a random integer within a CW, which is defined by a minimum (CWmin) and maximum (CWmax) value. Critically, Ho was asserted to teach that if doubling the CW after a failed transmission would exceed CWmax, the CW is set to CWmax. This directly maps to the limitation in claim 5.
    • Motivation to Combine: A POSITA would incorporate Ho’s teachings to improve system stability and reliability. Petitioner argued that implementing a standardized and bounded contention backoff mechanism, as taught by Ho, is a fundamental technique in wireless communications to manage retransmissions and prevent excessive delays. Adding this well-understood principle of bounded exponential backoff to the framework of Zhou-Cherian-Kim was presented as a logical step to enhance the robustness of the overall system.
    • Expectation of Success: The integration leverages a well-known and reliable technique (bounded backoff) to address potential collisions, a common issue in wireless systems. Therefore, a POSITA would expect this combination to work predictably.

Ground 3: Obviousness over Zhou, Cherian, Kim, and Bharghavan - Claims 6-7 are obvious over Zhou, Cherian, and Kim in view of Bharghavan.

  • Prior Art Relied Upon: Zhou (Application # 2017/0202023), Cherian (Application # 2017/0325264), Kim (Application # 2018/0034595), and Bharghavan (Patent 9,197,482).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground adds Bharghavan to the base combination to address claims 6 and 7, which concern operating a plurality of queues classified by access category. Petitioner asserted that Bharghavan teaches optimizing Quality of Service (QoS) by managing multiple queues and dynamically adjusting channel access parameters based on real-time traffic conditions. Specifically, Bharghavan was argued to teach that if a particular queue has no data stored and its corresponding backoff timer is zero, no operation is performed at the slot boundary. Bharghavan further teaches maintaining the backoff timer at zero in this state, mapping directly to the limitations of claims 6 and 7.
    • Motivation to Combine: A POSITA would be motivated to combine Bharghavan to achieve enhanced QoS management and more efficient medium access control. Petitioner argued that integrating Bharghavan’s queue-status-aware adjustments into the Zhou-Cherian-Kim system would provide a more context-aware, dynamic method for managing channel access, such as by preventing unnecessary contention when certain traffic types are inactive. This addresses a known design need for efficient resource utilization.
    • Expectation of Success: The combination relies on known hardware and software capabilities to execute algorithms for parameter selection, mode transition, and dynamic adjustments based on queue status. This leverages known building blocks to achieve a predictable improvement in network performance and QoS.

4. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-10 of the ’035 patent as unpatentable.