LG Electronics Inc v. Jawbone Innovations LLC

1. Case Identification

• Case #: IPR2023-01112
• Patent #: 8,321,213
• Filed: June 23, 2023
• Petitioner(s): LG Electronics Inc.
• Patent Owner(s): Jawbone Innovations, LLC
• Challenged Claims: 14-42

2. Patent Overview

• Title: Noise Suppression Systems, Devices, and Methods
• Brief Description: The ’213 patent relates to noise suppression systems that use two physical microphones to generate two "virtual microphones." The system detects acoustic voice activity by calculating an energy ratio between the signals from the two virtual microphones and comparing that ratio to a threshold value.

3. Grounds for Unpatentability

Ground 1: Claims 14-17 and 35-42 are obvious over Avendano and Visser.

• Prior Art Relied Upon: Avendano (Patent 8,194,880) and Visser (Patent 7,464,029).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Avendano disclosed all core limitations of independent claims 14 and 42. Avendano taught an audio device with two physical microphones that generate respective signals. A processing component formed two virtual microphones (a "cardioid primary signal" and a "cardioid secondary signal") by combining the microphone signals, with one path including a delay filter. Avendano then calculated the energy ratio ("Inter-Level Difference") of these two virtual microphone signals and compared it to a threshold to detect speech. Petitioner contended that to the extent Avendano did not disclose an adaptive filter, Visser supplied this element. Visser taught an adaptive "ICA process" using cross filters to improve the separation of speech and noise channels from two microphone inputs.
  • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine Visser's adaptive filtering with Avendano's voice activity detection system. Petitioner asserted this combination would improve the accuracy of speech detection by better separating speech from noise, particularly in changing acoustic environments, which was a known goal in the art.
  • Expectation of Success: A POSITA would have a reasonable expectation of success because both Avendano and Visser operated on similar inputs (signals from two microphones) for a similar purpose (creating processed signals to distinguish speech from noise). Integrating Visser's known adaptive filtering technique into Avendano’s similar system was presented as a straightforward modification.

Ground 2: Claims 18-26 and 33-34 are obvious over Avendano and Visser, in view of Bisgaard.

• Prior Art Relied Upon: Avendano (Patent 8,194,880), Visser (Patent 7,464,029), and Bisgaard (Application # US 2011/0103626).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground built upon the Avendano/Visser combination by adding Bisgaard to address limitations in claims dependent on claim 17, particularly claim 18. Petitioner argued that Bisgaard explicitly taught setting a delay to be "proportional to a time difference between arrival of the speech" at two microphones. Bisgaard disclosed delaying a digitized sound signal by the amount of time required for sound to propagate from a front microphone to a rear microphone.
  • Motivation to Combine: A POSITA implementing the delay in the Avendano system would look to analogous systems like Bisgaard for details on how to configure that delay. Petitioner argued it would have been obvious to apply Bisgaard's teaching to set the delay in the combined Avendano/Visser system to account for the physical spacing and sound arrival time difference between the microphones, thereby improving system performance.
  • Expectation of Success: The combination was presented as predictable, as it involved applying a known delay implementation (Bisgaard) to a functionally similar delay element (in Avendano) for its intended and understood purpose.

Ground 3: Claims 27-29 are obvious over Avendano, Visser, and Bisgaard, in view of Hou.

• Prior Art Relied Upon: Avendano (Patent 8,194,880), Visser (Patent 7,464,029), Bisgaard (Application # US 2011/0103626), and Hou (Patent 7,155,019).

• Core Argument for this Ground:

  • Prior Art Mapping: This ground added Hou to address the limitations of claim 27, which required forming a filter as a ratio of two quantities derived from applying calibration and delay to the microphone signals. Petitioner contended Hou taught a method to compensate for sensitivity mismatches between microphones by estimating minimums for each signal, applying a delay to one, and then forming a quotient (ratio) of the two estimates to create a scaling amount. This scaling amount was argued to be the claimed filter.
  • Motivation to Combine: A POSITA would recognize that both Avendano and Hou addressed the problem of equalizing signals from two microphones. Petitioner argued a POSITA would be motivated to implement Hou's specific compensation system in the base combination to further improve the equalization of microphone signals, leading to more robust directionality and noise suppression.
  • Expectation of Success: Given that Hou's system performed a similar function to Avendano's "gain factor," a POSITA would have reasonably expected that substituting or augmenting Avendano's method with Hou's more detailed approach would successfully improve performance.

• Additional Grounds: Petitioner asserted an additional obviousness challenge for claims 30-32 based on the combination of Avendano, Visser, Bisgaard, and Hou in view of "Frequency Art" (Byrne, Burnett, and/or Berglund). This ground argued that a POSITA would obviously perform the speech detection process in specific frequency subbands (e.g., 250-1250 Hz or 200-3000 Hz) known to contain significant spectral components of human speech while filtering out frequencies known to be dominated by noise.

4. Arguments Regarding Discretionary Denial

• Petitioner argued against discretionary denial under Fintiv, stating that the co-pending district court litigation was in its earliest stages, with no trial date set and minimal investment by the parties. Petitioner further noted it would move to stay the litigation and stipulated not to pursue the IPR grounds in court if a stay was denied, thus mitigating concerns of duplicative efforts.
• Petitioner also argued against denial under §325(d) and General Plastic, asserting that the primary prior art reference, Avendano, was never considered by the PTO during the original examination of the ’213 patent. Furthermore, Petitioner stated that this petition was filed to seek joinder with a previously filed petition by another party, a practice the Board has found permissible.

5. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 14-42 of the ’213 patent as unpatentable.