Ericsson Inc v. Intellectual Ventures I LLC

1. Case Identification

• Case #: IPR2015-01367
• Patent #: 5,602,831
• Filed: June 10, 2015
• Petitioner(s): Ericsson Inc. and Telefonaktiebolaget LM Ericsson
• Patent Owner(s): Intellectual Ventures I LLC
• Challenged Claims: 1-17

2. Patent Overview

• Title: Adaptive Communication Channel
• Brief Description: The ’831 patent discloses a method and system for wireless data transmission that adapts to mitigate errors caused by receiver motion. The system varies the number of data packets grouped into a "packet block" based on changes in signal drop-out characteristics, which are correlated with the receiver's speed.

3. Grounds for Unpatentability

Ground 1: Claims 1-3, 6-7, and 9-14 are obvious over the ’731 patent in view of the ’051 patent.

• Prior Art Relied Upon: Gaske (Patent 4,939,731, the ’731 patent) and Bodin (Patent 5,425,051, the ’051 patent).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that the ’731 patent teaches the core concept of the ’831 patent: varying the number of smaller data units within a larger data unit based on channel quality. Specifically, the ’731 patent discloses varying the number of "S-blocks" (the claimed "packets") within a "packet" (the claimed "packet block") by adjusting the baud rate in response to the detected error rate. The ’051 patent supplies the missing link to receiver speed by explicitly teaching that signal fading and drop-outs (i.e., error rates) are directly correlated with the relative speed of the mobile receiver and that data segment size should be adjusted accordingly.
  • Motivation to Combine: A Person of Ordinary Skill in the Art (POSA) would combine the references to improve the error-rate-based system of the ’731 patent. The ’051 patent provides a clear explanation for the cause of the errors that the ’731 patent seeks to mitigate—namely, receiver motion. A POSA would have been motivated to use the teachings of ’051 to adapt the packet size in the ’731 system based on the specific cause of channel degradation (receiver speed) rather than just its symptom (general error rate).
  • Expectation of Success: A POSA would have had a high expectation of success because combining the references involves applying a known principle (the effect of speed on fading from ’051) to improve a known system (the adaptive data rate system of ’731) to achieve a predictable result of more robust communication.

Ground 2: Claim 8 is obvious over the ’731 patent and the ’051 patent in view of Webb.

• Prior Art Relied Upon: The ’731 patent, the ’051 patent, and Webb (an IEEE article titled "Bandwidth Efficient QAM Schemes for Rayleigh Fading Channels").
• Core Argument for this Ground:
  • Prior Art Mapping: This ground builds on the combination in Ground 1 to address claim 8, which adds the limitation of varying the number of packets based on the "content of the packets." Webb teaches that different types of data, such as computer data versus voice, have vastly different error tolerances ("integrity constraints"). Webb discloses that data transmissions require significantly more error protection than voice transmissions.
  • Motivation to Combine: A POSA, seeking to optimize the adaptive system of ’731 and ’051, would be motivated to incorporate Webb’s teachings to apply different error protection strategies based on the content being transmitted. This would allow the system to make more nuanced adjustments, for example, by using different error-rate thresholds for voice packets versus data packets, thereby improving overall system efficiency.

Ground 3: Claims 4-5 are obvious over the ’731 patent and the ’051 patent in view of Wong.

• Prior Art Relied Upon: The ’731 patent, the ’051 patent, and Wong (an article titled "Channel Coding for Satellite Mobile Channels").
• Core Argument for this Ground:
  • Prior Art Mapping: This ground addresses claims 4 and 5, which add limitations related to well-known block interleaving techniques. The ’731 patent already discloses interleaving to protect against burst errors. Wong provides a detailed explanation of standard block interleaving, a prevalent technique at the time for breaking up burst errors. Wong illustrates how packets are combined in a sequential order into a memory matrix and then read out in a different order, which inherently meets the claim limitations of combining data locations.
  • Motivation to Combine: A POSA implementing the interleaving suggested in the ’731 patent would have naturally turned to well-known methods like the block interleaving described in Wong. This would not be an inventive step but rather the implementation of a common design choice to achieve the known benefits of interleaving.

Ground 4: Claims 15-17 are obvious over the ’731 patent, the ’051 patent, and Wong, in view of the ’449 patent.

• Prior Art Relied Upon: The ’731 patent, the ’051 patent, Wong, and Van Zanten (Patent 5,379,449, the ’449 patent).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground challenges claims 15-17, which require explicitly "identifying a given speed that the receiver is moving." While the ’051 patent teaches correlating fading with speed, the ’449 patent explicitly discloses using a vehicle speed sensor to provide a speed signal to a radio system to select appropriate corrective actions in response to multipath interference.
  • Motivation to Combine: A POSA building the adaptive system taught by the primary references would be motivated to incorporate the ’449 patent’s direct speed measurement approach. Using a vehicle speed sensor provides a more direct and reliable input for "identifying a given speed" than inferring it from signal characteristics, representing a straightforward and obvious improvement to the system.

4. Key Claim Construction Positions

• "packet" / "packet block": Petitioner argued that these terms should be construed based on their function within the system, not their labels. The ’731 patent’s smaller "S-block" meets the construction of a "packet" ("a section of data that is communicated as a unit"), and its larger "packet" meets the construction of a "packet block" ("a block of data including a discrete number of packets"). Petitioner contended this terminological difference does not create patentable distinction.
• "signal drop-out characteristics": Proposed as "characteristics of signal drop-outs." This construction was argued to be broad enough to encompass the error rates disclosed in the ’731 patent and the signal fading characteristics disclosed in the ’051 patent.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that the Board should exercise its discretion to institute review despite a previously denied petition (IPR2014-00958) under 35 U.S.C. §325(d). The primary reasons asserted were that this petition raises new grounds based on compelling primary and secondary prior art references that were not known or available to the Petitioner at the time of the first filing. Petitioner asserted the new grounds and arguments are substantially different from the prior petition, which focused on different art, and therefore do not represent an improper "second bite at the apple."

6. Relief Requested

• Petitioner requested institution of an inter partes review and cancellation of claims 1-17 of the ’831 patent as unpatentable under 35 U.S.C. §103.