CommScope Technologies LLC v. Dali Wireless Inc

1. Case Identification

• Case #: IPR2022-01242
• Patent #: 11,026,232
• Filed: July 1, 2022
• Petitioner(s): CommScope Technologies LLC, Corning Optical Communications LLC
• Patent Owner(s): Dali Wireless, Inc.
• Challenged Claims: 1-20

2. Patent Overview

• Title: Reconfigurable Distributed Antenna System
• Brief Description: The ’232 patent discloses a distributed antenna system (DAS) that dynamically assigns different subsets of radio resources (e.g., RF carriers) to various remote radio head units. This "flexible simulcast" allows the system to reallocate capacity in response to changing subscriber needs, such as when users move within a building, causing traffic loads to shift.

3. Grounds for Unpatentability

Ground 1: Claims 1-7, 9, 11-17, and 19-20 are obvious over Hettstedt in view of Wellington.

• Prior Art Relied Upon: Hettstedt (Application # 2008/0119198) and Wellington (Patent 8,112,094).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Hettstedt, a reference considered during prosecution, disclosed all limitations of the claims except for the specific clause added by amendment: "which of the second subset is loaded beyond a threshold." Hettstedt taught a DAS with a central "cell management unit" that shifts radio carriers between remote radio heads in response to changing traffic loads (e.g., from low-traffic to high-traffic areas). Wellington, a new reference, was argued to cure this deficiency by explicitly disclosing a method for managing cell congestion where an additional carrier is automatically allocated when the load on an existing carrier subset reaches a "predetermined level" or "predetermined threshold."
  • Motivation to Combine: A POSITA would combine Wellington's threshold-based trigger with Hettstedt's load-balancing system to make it more efficient and automatic. Hettstedt’s system required a mechanism to decide when to shift carriers due to "high load," and Wellington provided a known, machine-executable method for doing so, thereby improving the adaptability of Hettstedt's system without requiring human input or complex software reprogramming.
  • Expectation of Success: A POSITA would have a high expectation of success, as Hettstedt already disclosed the means for detecting load ("air activity detection"). Implementing Wellington’s teaching would only require a simple, predictable comparison operation (e.g., an "if/then" statement) using a standard processor.

Ground 2: Claims 1-7, 9, 11-17, and 19-20 are obvious over Hettstedt itself.

• Prior Art Relied Upon: Hettstedt (Application # 2008/0119198).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner contended that the Examiner erred during prosecution by overlooking a key disclosure within Hettstedt itself. While the Examiner concluded Hettstedt did not teach the "threshold" limitation, Petitioner pointed to Hettstedt's own claims (specifically claim 3), which disclosed activating shifted carriers at remote radio heads that "are loaded over a predetermined value."
  • Motivation to Combine (N/A - single reference): Petitioner argued that this teaching in Hettstedt's own claims rendered the "threshold" limitation obvious. A POSITA reading Hettstedt would have understood that "high load" could be defined by a "predetermined value," which is synonymous with a threshold, and would have been motivated to use this value to trigger the load-balancing carrier shifts described in Hettstedt's specification.
  • Expectation of Success: Success was predictable because Hettstedt disclosed all necessary components: a system for shifting carriers, a method for detecting load, and the concept of a "predetermined value" to define when a load is high enough to warrant action.

Ground 3: Claims 1-7, 9, 12-17, and 19-20 are obvious over Wu, either alone or in combination with Sabat.

• Prior Art Relied Upon: Wu (Application # 2010/0128676) and Sabat (Application # 2009/0180426).

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner asserted that Wu taught a carrier transport system where a central matrix switch dynamically allocates carrier channels to different remote transceiver units (RTUs) based on a configurable routing policy. This policy could be triggered by events, changing traffic loads, or "threshold criteria" to "allocate more channels" where needed. This was argued to meet all limitations of the independent claims, including assigning additional resources in response to a subset being loaded beyond a threshold. Sabat was introduced primarily to address the "Common Public Radio Interface (CPRI) protocol" limitation, as Sabat explicitly taught using the CPRI protocol for the communication link between a DAS central node and a digital base station.
  • Motivation to Combine: A POSITA would combine Wu with Sabat to enable Wu's flexible system to interface with modern digital base stations, which was a known and desirable goal. Using the standardized CPRI protocol, as taught by Sabat, was an obvious choice to achieve this interoperability, providing benefits of digital signaling (e.g., noise immunity, scalability) that were well-understood in the art.
  • Key Aspects: Petitioner emphasized that the PTAB had previously found similar claims in the Patent Owner's related patents invalid over Wu in prior IPRs, and that the Patent Owner had even cancelled claims in one of those patents when faced with Wu.

• Additional Grounds: Petitioner asserted additional obviousness challenges, including combining the primary grounds with Fischer (Application # 2010/0177759) to add IP communication capability (for claims 8 and 18) and with Conyers (Patent 7,398,106) to add software-configurable transmission power (for claim 10).

4. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under §314(a) or §325(d) was unwarranted. The lead ground (Hettstedt and Wellington) presented a new reference, Wellington, that was not before the Examiner and directly addressed the specific limitation added to overcome the Examiner's rejection over Hettstedt. Furthermore, Petitioner contended the Examiner made a material error by overlooking the "predetermined value" teaching in Hettstedt's own claims (Ground 2) and by never substantively examining Wu, which was only submitted in an IDS after a notice of allowance had already issued.

5. Relief Requested

• Petitioner requested the institution of an inter partes review and the cancellation of claims 1-20 of Patent 11,026,232 as unpatentable under 35 U.S.C. §103.