PTAB

IPR2013-00125

Research In Motion Corp v. Wi LAN Inc

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1. Case Identification

2. Patent Overview

  • Title: Method for Frequency Sharing and Frequency Punchout in Frequency Hopping Communications Network
  • Brief Description: The ’369 patent discloses a method for nodes in a wireless frequency-hopping network to establish unique communication plans. The method involves assigning each node a unique seed value and using a "channel punchout mask" to eliminate interfering channels from a master list, thereby creating a customized subset of available channels for that node to use for communication.

3. Grounds for Unpatentability

Ground 1: Anticipation and Obviousness over Munday - Claims 5 and 7 are unpatentable over Munday.

  • Prior Art Relied Upon: Munday (Patent 5,377,221).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued Munday anticipates each limitation of independent claim 5. Munday describes a frequency hopping radio system where radios monitor all channels to identify a subset with the lowest interference (the "channel punchout mask"). A pseudo-random hopping sequence is generated using a "keystream generator" seeded by a unique "key of the day" and timing sync data (the "unique seed value"). By transmitting the low-interference channel identities and the sync data, Munday communicates the band plan to other nodes. For dependent claim 7, which requires the mask to be a binary sequence, Petitioner argued this was an obvious modification. While Munday teaches a mask (the subset of usable channels), it was well known that using a binary sequence (0s and 1s) to represent such a mask was a common and obvious method to reduce transmission overhead.
    • Motivation to Combine (for §103 ground): For claim 7, a POSITA would be motivated to use a binary sequence for the mask to reduce the complexity and overhead associated with transmitting the full identities of every usable channel, a standard efficiency improvement.
    • Expectation of Success (for §103 ground): A POSITA would have a high expectation of success in using a binary mask, as it was a conventional and well-understood technique in digital communications for representing channel availability.

Ground 2: Anticipation and Obviousness over Jackson - Claims 5, 7, and 9 are unpatentable over Jackson.

  • Prior Art Relied Upon: Jackson (“Advanced HF Anti-Jam Network Architecture,” a 1990 publication).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner contended that Jackson anticipates claims 5 and 9. Jackson discloses a multi-node frequency hopping network where each user is assigned a unique hopping pattern. Nodes monitor the quality of a large set of frequencies (e.g., 512) and report this to a control station, which then assigns a smaller "hop set" of high-quality frequencies (e.g., 64). Petitioner mapped this selection of a preferred subset to the claimed "channel punchout mask." The unique hopping patterns are based on pseudo-random sequences, which inherently require a unique seed value to ensure uniqueness for each user. Jackson communicates this plan by sending the hop set assignment over an orderwire link. Petitioner asserted this communication necessarily includes the unique seed and the mask, thus anticipating claim 9 as well. For dependent claim 7, Petitioner reprised the argument that implementing the mask as a binary sequence was an obvious design choice for efficiency.
    • Motivation to Combine (for §103 ground): The motivation for modifying Jackson to meet claim 7 was to improve network efficiency by reducing the data overhead required to communicate the hop set, a common goal in network design.
    • Expectation of Success (for §103 ground): Success would be expected, as applying a standard binary masking technique to represent a subset of channels was a straightforward and predictable implementation detail.

Ground 3: Obviousness over Jackson in view of Flammer - Claim 6 is obvious over Jackson in view of Flammer.

  • Prior Art Relied Upon: Jackson (a 1990 publication) and Flammer (Patent 5,079,768).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground addresses dependent claim 6, which requires the unique seed value to be "derived from an address of the node." Petitioner established Jackson as the base reference teaching all elements of claim 5. Flammer was introduced because it is directed to the same field of frequency hopping communications and explicitly teaches deriving a "random offset 'seed' value... from a node address." This seed is used for the express purpose of generating a unique channel-hopping band plan.
    • Motivation to Combine: A POSITA would combine these references to solve the problem of how to assign unique seeds in the Jackson network. Flammer provides a direct and well-understood solution—using the node's unique address—for this exact purpose. Because both patents address the same problem of creating unique hopping plans, applying Flammer’s specific technique to the more general Jackson system would have been a predictable and logical design step.
    • Expectation of Success: A POSITA would have had a high expectation of success, as combining the teachings involved applying a known technique (deriving a seed from an address) to a similar system (a frequency hopping network) to achieve a predictable result (a unique hopping plan for each node).

4. Key Claim Construction Positions

  • "channel punchout mask": Petitioner argued this term should be given its broadest reasonable interpretation and not be limited to a specific structure, such as a bitmask. Based on the ’369 patent’s file history, Petitioner contended the term should encompass any data structure that indicates which channels are unusable due to interference, including a simple list or table of invalid/valid channels. This broad construction was critical to Petitioner's arguments that the prior art’s disclosure of selecting a "subset" of low-interference channels met this limitation.

5. Relief Requested

  • Petitioner requested institution of an inter partes review (IPR) and cancellation of claims 5-7 and 9 of the ’369 patent as unpatentable.