PTAB

IPR2024-01142

AT&T Enterprises LLC v. ASUS Technology Licensing Inc

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Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Method and Apparatus for Beamforming in Wireless Communication System
  • Brief Description: The ’868 patent is directed to methods and apparatuses for beamforming in a wireless system. The technology involves a user equipment (UE) deriving a "UE beam" based on a beam reference signal from a "network beam," where information about the network beam is provided via Medium Access Control (MAC) signaling.

3. Grounds for Unpatentability

Ground 1: Obviousness over Jung - Claims 5, 6, 8, 13, 14, 16, and 18 are obvious over Jung

  • Prior Art Relied Upon: Jung (Patent 11,539,419).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Jung teaches all limitations of the challenged claims. Independent claims 5 and 13 require a network node to select a network beam, transmit a "first signal" using MAC signaling to a UE, which then derives a "UE beam" based on the network beam's reference signal. This derived UE beam is used to transmit periodic Channel State Information (CSI) and a scheduling request (SR). The network node then uses the network beam, mapped to the UE beam, to receive the CSI and SR. Petitioner asserted Jung discloses selecting a "best beam" (network beam) and transmitting various MAC signals (e.g., a MAC-CE with a beam ID or feedback duration) that constitute the claimed "first information." Jung allegedly teaches that a UE measures a beam reference signal to determine its best corresponding UE beam. Based on channel reciprocity, which Jung discloses, this beam is used for both transmission and reception. Jung further teaches the periodic transmission of beam feedback, which can include CSI, and the transmission of an SR over the selected best beam. The principle of channel reciprocity also allegedly teaches that the network beam used for downlink transmission is inherently mapped to the UE beam for uplink reception.
    • Key Aspects: Petitioner contended that dependent claims are also obvious, as Jung discloses transmitting a second signal with radio resource allocation (claims 6 and 14), that this signal can be a Radio Resource Control (RRC) message (claims 8 and 14), and transmitting an indication of candidate network beams (claims 16 and 18).

Ground 2: Obviousness over Jung in view of Xiong - Claims 5, 6, 8, 13, 14, 16, and 18 are obvious over Jung in view of Xiong

  • Prior Art Relied Upon: Jung (Patent 11,539,419) and Xiong (Patent 11,096,195).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Jung provides the foundational teachings for all claim limitations, as detailed in Ground 1. To the extent Jung might be found not to explicitly teach using the derived UE beam to transmit a scheduling request, Xiong supplies this disclosure. Xiong explicitly teaches that a UE selects a receive (Rx) beam based on a beamforming reference signal and then transmits a scheduling request to the network node "using the selected Rx beam." In view of the channel reciprocity taught by both Jung and Xiong, a POSITA would understand that the selected Rx beam is also the appropriate beam for transmission.
    • Motivation to Combine: A POSITA would combine Jung and Xiong because they address the same technical problem in the same field: beam management in 5G networks using high-frequency bands. Both references disclose using beam reference signals for beam selection and rely on channel reciprocity. Petitioner asserted a POSITA, seeking to implement the beam management system of Jung, would naturally look to a reference like Xiong for specific, improved methods of transmitting control signals like a scheduling request, making the combination a predictable application of known techniques.
    • Expectation of Success: A POSITA would have a high expectation of success in combining the references. The integration would involve using Xiong's explicit teaching for transmitting an SR on a selected beam within Jung's broader, compatible beam management framework, which already contemplates transmitting SRs.

4. Arguments Regarding Discretionary Denial

  • Petitioner argued against discretionary denial under Fintiv, asserting that multiple factors favor institution. Key arguments included that the prior art (Jung and Xiong) was not before the examiner during prosecution, weighing strongly for institution. The parallel district court litigation is in its early stages with minimal investment, as fact discovery is nascent and no substantive orders have been issued. Petitioner also stipulated that, if trial is instituted, it will not pursue the same IPR grounds in the district court litigation, which eliminates concerns of duplicative efforts and conflicting decisions. Finally, Petitioner asserted the petition presents compelling merits that plainly show at least one claim is unpatentable, which is the most important factor.

5. Relief Requested

  • Petitioner requests institution of IPR and cancellation of claims 5, 6, 8, 13, 14, 16, and 18 of the ’868 patent as unpatentable.