PTAB

IPR2017-01982

Huawei Technologies Co Ltd v. Samsung Electronics Co Ltd

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Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Method and Apparatus for Detecting Contention in a Mobile Communication System
  • Brief Description: The ’827 patent discloses a method for managing contention during a random access (RA) procedure in a mobile communication system. The technology centers on a User Equipment (UE) activating a timer after transmitting a message; if UE-specific control information is not received from the base station before the timer expires, the UE determines the contention is not resolved and restarts the procedure.

3. Grounds for Unpatentability

Ground 1: Claims 9-14 are obvious over Pajukoski, Nokia 901, and TS 25.212.

  • Prior Art Relied Upon: Pajukoski (Patent 9,301,318), Nokia 901 (3GPP R1-061901), and TS 25.212 (3GPP TS 25.212 Version 6.7.0).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that the combination of these three references teaches every limitation of the challenged claims. Pajukoski was asserted to disclose the foundational random access procedure, including a UE transmitting a message with a temporary identifier (a C-RNTI, if available) and waiting for a response to resolve contention. However, Pajukoski does not explicitly teach the UE activating its own timer. To supply this element, Petitioner relied on Nokia 901, which teaches a UE starting a timer after transmitting its message containing a C-RNTI. In Nokia 901, if the timer expires before a response is received, the UE concludes a collision has occurred and restarts the process. Finally, to meet the limitation requiring a Cyclic Redundancy Check (CRC) mapped to the C-RNTI, Petitioner pointed to TS 25.212. This 3GPP standard was argued to teach the well-known technique of masking a CRC value with a UE identity (like a C-RNTI) to simultaneously provide error detection and identify the intended recipient in a single, efficient field.
    • Motivation to Combine: Petitioner contended that a person of ordinary skill in the art (POSITA) would have been motivated to combine these references to create a more efficient and reliable system. A POSITA would combine Pajukoski with Nokia 901 because Nokia 901’s timer-based contention resolution is more resource-efficient, requiring only a single downlink message to the winning UE, whereas Pajukoski’s method requires two. This modification aligns with Pajukoski’s own stated goal of designing a procedure with “minimum use of resources.” A POSITA would then incorporate the masked CRC from TS 25.212 into the combined Pajukoski/Nokia 901 system. This would provide robust error detection and correction—a known benefit of CRCs—without increasing the size of the control message, thereby improving both reliability and signaling efficiency.
    • Expectation of Success: Petitioner asserted a POSITA would have had a reasonable expectation of success. The combination involved applying known techniques (timer-based resolution, masked CRCs) from analogous art (all references relate to UTRA or LTE systems) to achieve predictable improvements in efficiency and reliability. The integration was presented as a straightforward substitution of known, complementary elements.

4. Key Claim Construction Positions

  • “User Equipment (UE)-Specific Control Information Addressable by the C-RNTI” (Claims 9, 12): Petitioner argued this term should be construed to include control information identified either by an explicit C-RNTI or by a CRC that is mapped to the C-RNTI. This construction was crucial for mapping the teachings of TS 25.212, which discloses masking a CRC with a UE identity, to the claims.
  • “Activating a Timer for Collision Detection” (Claims 9, 12): Petitioner proposed this phrase should broadly cover activating any timer used for contention detection. This construction was necessary to apply the teachings of Nokia 901, which describes starting a timer to detect a "preamble collision," to the patent's specific claim language.
  • “A Contention Resolution (CR) Message” (Claims 10, 13): Petitioner argued this term should encompass any message that allows a UE to determine whether it has won or lost a random access contention. This interpretation allowed the UL allocation message in the combined prior art, which identifies the winning UE, to be considered a "CR message."

5. Arguments Regarding Discretionary Denial

  • Petitioner argued that discretionary denial under 35 U.S.C. §325(d) would be improper. The petition asserted that its challenge was based on two key prior art references (Nokia 901 and TS 25.212) that were not cited or considered during the original prosecution of the ’827 patent. Furthermore, the petition's arguments were supported by detailed expert testimony, presenting a stronger and more complete case than what the Examiner had previously reviewed.

6. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 9-14 of Patent 8,228,827 as unpatentable.