LG Electronics Inc v. Jawbone Innovations LLC

1. Case Identification

• Case #: IPR2023-01154
• Patent #: 8,019,091
• Filed: July 5, 2023
• Petitioner(s): LG Electronics Inc.
• Patent Owner(s): Jawbone Innovations, LLC
• Challenged Claims: 1-20

2. Patent Overview

• Title: Systems and Methods for Removing Noise from a Signal
• Brief Description: The ’091 patent discloses systems and methods for reducing acoustic noise from speech signals. The technology uses a two-microphone array and a processor that calculates first and second transfer functions based on whether a separate non-acoustic voicing sensor (e.g., an accelerometer) detects user speech, and then applies these functions to remove noise.

3. Grounds for Unpatentability

Ground 1: Obviousness over Ikeda and Puthuff - Claims 1-8, 11-14, 16, 18-20 are obvious over Ikeda in view of Puthuff.

• Prior Art Relied Upon: Ikeda (Patent 5,978,824) and Puthuff (WO 2000/021194).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Ikeda disclosed the core elements of the challenged claims: a two-microphone noise canceling system that uses adaptive filters to generate first and second transfer functions. Ikeda generates a first transfer function (W1(z)) when voice is absent and a second (W2(z)) when voice is present to produce a denoised output signal. However, Ikeda’s voice activity detector (VAD) is acoustic-based (a signal-to-noise power ratio estimator). Puthuff was cited for disclosing the missing element: a VAD that uses a non-acoustic vibration sensor, such as an accelerometer, to detect "speech-induced vibrations" from a user's tissue. Puthuff taught using this sensor to improve voice detection in noisy environments where acoustic VADs fail.
  • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine these references because both addressed the problem of accurately detecting voice activity in noisy environments. A POSITA would have been motivated to replace or supplement Ikeda’s acoustic VAD with Puthuff’s more robust, noise-resistant vibration sensor to predictably improve the performance of Ikeda’s noise cancellation system. Puthuff expressly taught that its vibration sensor was useful for "dual microphone" systems like Ikeda's.
  • Expectation of Success: A POSITA would have a reasonable expectation of success because Puthuff’s sensor was a known, off-the-shelf component for voice detection, and the signal processing in Ikeda’s system would function irrespective of the VAD’s specific type, so long as it accurately indicated the presence or absence of voice.

Ground 2: Obviousness over Ikeda and Alcivar - Claims 1-8, 11-14, 16, 18-20 are obvious over Ikeda in view of Alcivar.

• Prior Art Relied Upon: Ikeda (Patent 5,978,824) and Alcivar (Patent 3,746,789).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground is substantially similar to Ground 1, with Alcivar substituting for Puthuff. Petitioner asserted that Ikeda provided the foundational two-microphone noise-canceling system. Alcivar, an earlier reference from 1973, disclosed a "tissue-conduction microphone" that functions as a VAD by detecting tissue vibrations from a user’s vocal chords to control a voice-activated switch.
  • Motivation to Combine: The motivation was similar to that for combining Ikeda and Puthuff. A POSITA would have been motivated to substitute Ikeda's acoustic VAD with Alcivar's simpler, cheaper, and more noise-resistant tissue-conduction microphone. Alcivar explained that its sensor could "discriminate against unwanted noises without having to resort to more elaborate signal processing techniques," making it an attractive and predictable improvement for Ikeda's system, which required accurate voice detection to function optimally.

Ground 3: Obviousness over Ikeda, Puthuff/Alcivar, and Hussain - Claims 3, 9, and 15 are obvious over the combinations in Grounds 1 or 2 in view of Hussain.

• Prior Art Relied Upon: Ikeda, Puthuff or Alcivar, and Hussain (a 1997 conference paper titled "A New Metric for Selecting Sub-Band Processing in Adaptive Speech Enhancement Systems").

• Core Argument for this Ground:

  • Prior Art Mapping: This ground built upon the combinations of Grounds 1 and 2 to address claims reciting sub-band processing (claims 9 and 15) and performance in reverberant environments (claim 3). Petitioner argued Hussain disclosed an adaptive noise cancellation scheme using a dual microphone array that improves performance by processing acoustic signals in separate sub-bands. Hussain taught dividing the signal from the microphones into multiple sub-bands, generating a "differential acoustic-path transfer function" for each sub-band, processing the noisy signal within each sub-band, and then reconstructing a single denoised signal.
  • Motivation to Combine: A POSITA would combine Hussain’s teachings with the Ikeda/Puthuff (or Ikeda/Alcivar) system to improve performance in reverberant environments, a common problem for devices like hands-free telephones. Hussain explicitly stated that sub-band processing "combat[s] reverberation effects" and yields significant signal-to-noise ratio improvements over conventional full-band methods like Ikeda’s. This presented a known solution to a known problem, yielding predictable results.
  • Expectation of Success: A POSITA would expect success because applying noise cancellation on individual sub-bands was a well-understood technique that would perform predictably in an adaptive system like the one disclosed by Ikeda.

• Additional Grounds: Petitioner asserted additional obviousness challenges, including that claims 10 and 17 are obvious over the primary combinations in view of Sasaki (Patent 5,471,538) for teaching directional microphones, and that all claims are obvious over the prior art combinations in view of Bartlett (Patent 5,473,684) for explicitly teaching the use of a digital signal processor to implement adaptive algorithms.

4. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under §314(a) based on Fintiv factors was inappropriate. The co-pending district court litigation was in its earliest stages, with no trial date set and minimal investment by the parties. Petitioner asserted it would move to stay the litigation pending the IPR. Furthermore, Petitioner stipulated that if the litigation is not stayed, it would not pursue the invalidity grounds raised in the petition in the district court, mitigating concerns of duplicative efforts.
• Petitioner also argued that denial under §325(d) was unwarranted because the primary prior art reference, Ikeda, had never been considered by the PTO during the original prosecution of the ’091 patent. Therefore, the petition raised new art and arguments not previously evaluated by the Office.

5. Relief Requested

• Petitioner requested the institution of an inter partes review and the cancellation of claims 1-20 of Patent 8,019,091 as unpatentable under 35 U.S.C. §103.