PTAB

IPR2022-00004

Google LLC v. Vocalife LLC

Log In
Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Microphone Array System
  • Brief Description: The ’049 patent describes methods and systems for enhancing a target sound signal captured by a microphone array. The system uses a sound source localization unit to identify the target, an adaptive beamforming unit to steer the array's directivity toward the target, and a noise reduction unit to suppress ambient noise.

3. Grounds for Unpatentability

Ground 1: Obviousness over Jeong, Van Trees, and Briere - Claims 1, 9, 18-22, 26, 29-35 are obvious over Jeong and Van Trees, optionally in view of Briere.

  • Prior Art Relied Upon: Jeong (Korean Patent Publication No. 10-2009-0037845), Van Trees ("Optimum Array Processing," a 2002 textbook), and Briere ("Embedded and Integrated Audition for a Mobile Robot," a 2006 publication).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Jeong taught the core system claimed in the ’049 patent, including a microphone array, a sound source searching unit (localization), an emphasized signal beam-former (beamforming), and a suppressed signal beam-former with a signal extracting unit (noise reduction). While Jeong disclosed using Time Delay of Arrival (TDOA) for localization, it did not detail the underlying mathematics. Van Trees, a standard textbook, provided the explicit, fundamental TDOA formulas for various microphone array geometries (e.g., linear, circular) that a person of ordinary skill in the art (POSITA) would use to implement Jeong’s system.
    • Motivation to Combine (for §103 grounds): A POSITA implementing Jeong’s system, which explicitly referenced using TDOA, would have been motivated to consult a standard textbook like Van Trees to obtain the well-known mathematical formulas necessary for that implementation. The combination amounted to applying a known technique (Van Trees’s formulas) to a known system (Jeong’s) to achieve a predictable result.
    • Expectation of Success (for §103 grounds): A POSITA would have had a high expectation of success, as Van Trees provided the standard, established mathematical framework for the exact TDOA methods mentioned in Jeong.
    • Key Aspects: Petitioner asserted that Briere was alternatively added to this combination to explicitly teach integrating the sound source localization, beamforming, and noise reduction units on a single digital signal processor (DSP). A POSITA would have been motivated to use a DSP for a portable device like Jeong’s to gain known benefits of real-time processing and power efficiency.

Ground 2: Obviousness over Jeong, Van Trees, and Buck-II - Claims 1, 3-5, 7-9, 11-13, 15, 17-23, 25, 26, 28-35 are obvious over Jeong and Van Trees in view of Buck-II.

  • Prior Art Relied Upon: Jeong, Van Trees, and Buck-II (Application # 2009/0067642).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground presented an alternative view where Jeong's components (emphasized beam-former, suppressed beam-former, and signal extractor) collectively constituted the "adaptive beamforming unit." Under this interpretation, Jeong lacked a separate, subsequent "noise reduction unit." Buck-II was argued to supply this missing element by teaching a noise reduction system with a post-filter that reduces residual noise from a beamformed signal.
    • Motivation to Combine (for §103 grounds): A POSITA would combine Buck-II’s post-filter with Jeong’s beamforming system to achieve Buck-II's expressly stated goal of improving speech quality and recognition by more effectively reducing noise. Since both systems utilized similar underlying components for beamforming, the integration would have been a straightforward application of a known noise reduction technique to improve a known system.
    • Expectation of Success (for §103 grounds): Success was expected because adding a post-filtering noise reduction step was a well-known process that used conventional algorithms to predictably reduce residual noise after beamforming.

Ground 3: Obviousness over Jeong, Van Trees, and Kim - Claims 2 and 10 are obvious over Jeong and Van Trees in view of Kim.

  • Prior Art Relied Upon: Jeong, Van Trees, and Kim (Application # 2009/0279714).

  • Core Argument for this Ground:

    • Prior Art Mapping: This ground challenged claims requiring the spatial location to be estimated using a "steered response power-phase transform" (SRP-PHAT). While Jeong taught sound localization generally, Kim explicitly taught using the SRP-PHAT algorithm to accurately determine a sound source’s location based on TDOA data, particularly in reverberant indoor environments.
    • Motivation to Combine (for §103 grounds): A POSITA seeking to improve the accuracy of the sound localization in Jeong's system would have been motivated to adopt the known, superior SRP-PHAT algorithm taught by Kim. This amounted to the simple substitution of one known localization algorithm for another to obtain the predictable benefit of improved performance.
    • Expectation of Success (for §103 grounds): A POSITA would have expected success, as Kim described SRP-PHAT as a well-known algorithm that provided accurate and real-time localization.

  • Additional Grounds: Petitioner asserted additional obviousness challenges against specific claims based on combinations including Yen (’187 application) for teaching adaptive filtering step-size adjustment and Andrea (’931 application) for teaching the use of audio codecs.

4. Key Claim Construction Positions

  • Petitioner argued that no terms required construction. However, it noted that a district court in related litigation had construed "adaptive beamforming" as "a beamforming process where the directivity pattern of the microphone array is capable of being adaptively steered in the direction of a target sound signal emitted by a target sound source in motion." Petitioner contended that the asserted prior art combinations disclosed this feature.

5. Arguments Regarding Discretionary Denial

  • Petitioner argued that discretionary denial under Fintiv would be improper. It asserted that the Fintiv factors favored institution because: (1) it intended to file a motion to stay the parallel district court litigation; (2) the trial date was uncertain and distant; (3) investment in the litigation had been minimal; (4) it would stipulate not to pursue in court any invalidity grounds raised in the IPR; and (5) the merits of the petition were strong.

6. Relief Requested

  • Petitioner requests institution of inter partes review and cancellation of claims 1-35 of Patent RE47,049 as unpatentable.