PTAB

IPR2018-01694

Ericsson Inc. v. Intellectual Ventures II LLC

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1. Case Identification

2. Patent Overview

  • Title: Uplink Power Control in a Wireless Network
  • Brief Description: The ’828 patent discloses methods and systems for uplink power control in a wireless network. The purported novelty is a hybrid power control method that strategically combines aspects of a conventional "open loop" scheme (where a user equipment (UE) sets power based on path loss) and a "closed loop" scheme (where the network sends transmit power control (TPC) commands) and provides an indication to the UE to switch between the combined scheme and a conventional scheme.

3. Grounds for Unpatentability

Ground 1: Obviousness over Zeira, Chen, and Cheng - Claims 1, 5, 8, 12, 15, 19, 22, 26, 29, 33, 36, and 40 are obvious over the combination of Zeira, Chen, and Cheng.

  • Prior Art Relied Upon: Zeira (Patent 6,728,292), Chen (Patent 7,532,572), and Cheng (Patent 6,411,817).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that the core limitations of independent claim 15 are taught by the combination. Zeira taught a combined open/closed loop power control system, including calculating transmit power based on both path loss and accumulated TPC commands. Chen taught sending an allocation of scheduled uplink resources on a dedicated control channel. Critically, Cheng taught sending a "physical layer control message" to a UE to instruct it to switch between different power control modes. The combination allegedly discloses all steps of claim 15, including sending an indication to enable/disable accumulation of TPC commands (from Cheng), determining path loss (from Zeira), receiving an allocation and TPC command on a single channel (from Zeira and Chen), and calculating transmit power based on either the combined method or just path loss (from Zeira).
    • Motivation to Combine: A person of ordinary skill in the art (POSITA) would combine Zeira and Chen to gain the benefits of sending TPC commands and resource allocations over the same efficient, dedicated channel. A POSITA would be further motivated to incorporate Cheng's mode-switching mechanism into Zeira's system to provide the network operator with the flexibility to dynamically select the most appropriate power control scheme (e.g., combined, pure open loop, or pure closed loop) based on network conditions or to ensure compatibility with legacy UEs.
    • Expectation of Success: A POSITA would have a reasonable expectation of success because combining the references involved applying known techniques (mode switching, channel allocation) to a known system (hybrid power control) to achieve the predictable result of a more flexible and efficient power control system.

Ground 2: Obviousness over Zeira, Chen, Cheng, and Tong - Claims 2, 9, 16, 23, 30, and 37 are obvious over the combination of Zeira, Chen, Cheng, and Tong.

  • Prior Art Relied Upon: Zeira (Patent 6,728,292), Chen (Patent 7,532,572), Cheng (Patent 6,411,817), and Tong (Patent 6,529,741).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground builds upon the combination in Ground 1. It addresses dependent claims requiring the TPC command to be a "multilevel TPC command." Petitioner asserted that Tong explicitly taught using more than one power control bit for a TPC command to allow for multiple, different step sizes for power adjustment, which is the definition of a multilevel TPC command.
    • Motivation to Combine: A POSITA would combine Tong's teachings with the base combination of Zeira, Chen, and Cheng as a matter of ordinary design choice. Zeira recognized the need for efficient adaptation in dynamic environments. Tong's multilevel commands provide such efficiency by enabling faster and larger power adjustments, which minimizes power overshoot and improves performance. This would have been a known solution to a known problem.
    • Expectation of Success: The combination was predictable, as it involved substituting a basic TPC command in the Zeira/Chen/Cheng system with the well-known, improved multilevel TPC command from Tong to achieve the expected benefit of more efficient power control.

Ground 3: Obviousness over Zeira, Chen, Cheng, and Shiu - Claims 6, 13, 20, 27, 34, and 41 are obvious over the combination of Zeira, Chen, Cheng, and Shiu.

  • Prior Art Relied Upon: Zeira (Patent 6,728,292), Chen (Patent 7,532,572), Cheng (Patent 6,411,817), and Shiu (Patent 6,983,166).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground also builds upon Ground 1. It addresses dependent claims requiring the calculated transmit power to be "based on a selected transport format." Petitioner argued that while Zeira's system calculated power based on a target signal-to-interference ratio (SIR), Shiu explicitly taught that this target SIR (or SNIR) is chosen based on the selected transport format to achieve a desired performance level (e.g., a target block error rate).
    • Motivation to Combine: A POSITA would combine Shiu's teachings with the base combination to improve the system's performance. It would have been apparent to a POSITA that adjusting the power control target based on the data format being transmitted (as taught by Shiu) is a logical and beneficial enhancement to Zeira's power control scheme. This allows the system to optimize power usage while maintaining quality of service for different applications.
    • Expectation of Success: A POSITA would reasonably expect success because combining the teachings was straightforward. It involved applying Shiu's known method for setting a target SIR to Zeira's system, which already used a target SIR, to predictably achieve the benefit of transport-format-dependent power control.

4. Key Claim Construction Positions

  • "accumulation of transmit power control (TPC) commands": Petitioner proposed construing this term to mean "increasing or decreasing transmit power based on a TPC command where the transmit power is also based on one or more previous TPC commands." This construction, based on the specification's description of an iterative process, was central to distinguishing the "closed loop" or "combined" modes (where accumulation is enabled) from the "open loop" mode (where it is not).
  • "multilevel TPC command": Petitioner proposed construing this term to mean "a TPC command that can represent one of more than two possible transmit power adjustments." This construction was critical to the obviousness argument for Ground 2, as it aligned the claim language with the disclosure of Tong, which taught using multiple bits to create more than two possible adjustment step sizes.

5. Relief Requested

  • Petitioner requested institution of an inter partes review and cancellation of claims 1-2, 5-6, 8-9, 12-13, 15-16, 19-20, 22-23, 26-27, 29-30, 33-34, 36-37, and 40-41 of Patent 8,897,828 as unpatentable under 35 U.S.C. §103.