PTAB

IPR2025-00838

Intel Corp v. USTA Technology LLC

Log In
Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Wireless Communication Network Interference Management
  • Brief Description: The ’720 patent relates to wireless communication networks, such as those using Orthogonal Frequency-Division Multiplexing (OFDM) and Multiple-Input/Multiple-Output (MIMO) technologies. The disclosed methods involve a first node (e.g., an access point) receiving instructions from other nodes to filter transmission signals by avoiding certain frequencies, receiving and decompressing feedback from those nodes, and simultaneously transmitting filtered signals to multiple nodes.

3. Grounds for Unpatentability

Ground 1: Obviousness over Walton and IEEE-802.11a - Claim 53 is obvious over Walton in view of IEEE-802.11a.

  • Prior Art Relied Upon: Walton (Application # 2003/0043732) and IEEE-802.11a (an IEEE Standard published in 1999).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Walton, a publication describing a MIMO-OFDM communication system, taught nearly all limitations of claim 53. Walton’s system included a base station (first node) that receives feedback as Channel State Information (CSI) from terminals (second and third nodes). This CSI contains a "channel mask" that functions as an instruction to avoid "bad" frequency subchannels. The base station then filters its transmission by allocating power only to the "good" subchannels. Walton also disclosed receiving compressed CSI feedback from multiple terminals and performing a complementary process to "recover" the reported CSI. The only element Petitioner contended Walton did not explicitly teach was the use of an "802.11-based" OFDM protocol.
    • Motivation to Combine: Petitioner asserted that a Person of Ordinary Skill in the Art (POSITA) would combine Walton's system with the IEEE-802.11a standard. Because Walton described a general OFDM system, a POSITA would have been motivated to implement it using the well-known, standardized IEEE-802.11a protocol to achieve predictable benefits such as product interoperability, economies of scale, and the use of existing, low-cost components.
    • Expectation of Success: A POSITA would have had a reasonable expectation of success because Walton’s network architecture (an access point communicating with multiple terminals) was the same as that used in standard IEEE 802.11 networks, making the incorporation of the protocol’s elements straightforward.

Ground 2: Obviousness over Walton, IEEE-802.11a, and McFarland - Claim 53 is obvious over the combination of Walton, IEEE-802.11a, and McFarland.

  • Prior Art Relied Upon: Walton (Application # 2003/0043732), IEEE-802.11a, and McFarland (Application # 2002/0006167).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground supplemented the combination in Ground 1 with McFarland to provide more explicit detail for the "filtering" limitation. While Walton taught avoiding "bad" channels, McFarland taught the specific and well-known technique for achieving this in an OFDM system: inputting zero-magnitude signals on the carriers (frequencies) that are not to be used before the Inverse Fast Fourier Transform (IFFT) step. Petitioner argued this process of zeroing inputs to the IFFT was the same "transmit excision" filtering method described in the ’720 patent’s specification.
    • Motivation to Combine: Petitioner argued that since Walton’s disclosure relied on what was "known in the art" for its IFFT implementation without providing specifics, a POSITA would have been motivated to look to a reference like McFarland. McFarland provided the missing implementation detail for filtering an OFDM signal with the benefits of easy implementation and power savings.
    • Expectation of Success: A POSITA would have expected success because McFarland’s technique was fully compatible with Walton’s OFDM modulator, which also used an IFFT. The combination represented the use of a known technique to improve a similar system for its intended purpose.

Ground 3: Obviousness over Walton, IEEE-802.11a, and Bohnke - Claim 95 is obvious over the combination of Walton, IEEE-802.11a, and Bohnke.

  • Prior Art Relied Upon: Walton (Application # 2003/0043732), IEEE-802.11a, and Bohnke (Application # 2002/0102940).

  • Core Argument for this Ground:

    • Prior Art Mapping: This ground addressed claim 95, which added limitations requiring that compressed feedback be repeatedly generated, compressed, and transmitted at time periods of less than one second. Walton taught periodic reporting of CSI but did not specify a numeric time interval. Bohnke was introduced to supply this teaching. Bohnke described that for mobile radio channels, updates should be based on the channel's "coherence time" and provided numerical examples for a 5 GHz system (as used in IEEE-802.11a) showing coherence times were substantially less than one second (e.g., ranging from 15 ms to 155 ms).
    • Motivation to Combine: A POSITA implementing Walton's system, which described time-varying link conditions typical of mobile terminals, would have been motivated to consult a reference like Bohnke to determine an appropriate update frequency. Bohnke taught that to ensure reliable channel estimation, the CSI update rate must be faster than the channel's coherence time.
    • Expectation of Success: A POSITA would have had a reasonable expectation of success in applying Bohnke’s teachings to adapt to changing channel conditions in periods of less than one second, as Bohnke provided evidence that this was a known and necessary design parameter for similar mobile networks.

  • Additional Grounds: Petitioner asserted additional obviousness challenges against claim 53 and 95 based on combinations that also included Peterson (a 1996 textbook) to further support the obviousness of decompressing a compressed signal, and McFarland to further support obviousness of filtering in the context of claim 95.

4. Arguments Regarding Discretionary Denial

  • Petitioner argued against discretionary denial under Fintiv by noting that the earliest proposed date for a final pretrial conference in the co-pending district court litigation (USTA Technology, LLC v. Lenovo Group Limited et al., 4-24-cv-00515 (EDTX)) was set for November 2026, which would occur after the statutory deadline for a Final Written Decision in this IPR.
  • Petitioner also noted that a real party-in-interest had filed a Sotera stipulation in the district court, agreeing not to pursue any invalidity ground in that litigation that was raised or reasonably could have been raised in this IPR, should the IPR be instituted.

5. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 53 and 95 of Patent RE47,720 as unpatentable.