DCT
2:23-cv-00347
Daingean Tech Ltd v. T-Mobile USA Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Daingean Technologies Ltd. (Ireland)
- Defendant: T-Mobile USA, Inc. (Delaware)
- Plaintiff’s Counsel: Alavi & Anaipakos PLLC
- Case Identification: 2:23-cv-00347, E.D. Tex., 05/08/2024
- Venue Allegations: Plaintiff alleges venue is proper in the Eastern District of Texas because T-Mobile operates substantial business, including retail stores, R&D facilities, and extensive 5G network infrastructure within the district, and has previously not contested venue in this district for similar actions.
- Core Dispute: Plaintiff alleges that Defendant’s 5G wireless telecommunications networks infringe three patents related to beamforming for interference avoidance, management of uplink transmissions, and efficient signaling of system information.
- Technical Context: The technology at issue involves core functionalities of 5G wireless networks, a critical infrastructure for high-speed mobile data, low-latency applications, and broad connectivity.
- Key Procedural History: The complaint is a First Amended Complaint. U.S. Patent No. 8,576,803 was assigned to Plaintiff Daingean Technologies from Mitsubishi Electric Corporation on August 23, 2022. No other significant procedural history is mentioned in the complaint.
Case Timeline
| Date | Event |
|---|---|
| 2006-11-29 | U.S. Patent No. 8,576,803 Priority Date |
| 2013-11-05 | U.S. Patent No. 8,576,803 Issued |
| 2016-07-28 | U.S. Patent No. 10,841,958 Priority Date |
| 2017-01-06 | U.S. Patent No. 10,484,976 Priority Date |
| 2019-11-19 | U.S. Patent No. 10,484,976 Issued |
| 2020-11-17 | U.S. Patent No. 10,841,958 Issued |
| 2024-05-08 | First Amended Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 8,576,803 - "Communication System," issued November 5, 2013
The Invention Explained
- Problem Addressed: The patent describes the technical problem of interference between mobile devices operating in adjacent or contiguous cells within a wireless communication system (’803 Patent, col. 2:1-2).
- The Patented Solution: The invention proposes a communication system where a base station forms a "transmission beam" to send data to a target mobile device. The characteristics of this beam are determined not only by signals from the target device but also by channel estimation signals received from mobile devices in adjacent areas and a calculated interference amount at those adjacent devices. This allows the system to direct the beam's energy toward the intended recipient while simultaneously creating nulls or areas of low energy in the direction of nearby devices to avoid causing interference (Compl. ¶35).
- Technical Importance: This beamforming and null-steering technique is intended to enhance frequency utilization and reduce signal degradation in dense cellular environments by actively managing inter-cell interference (Compl. ¶35).
Key Claims at a Glance
- The complaint asserts infringement of at least claim 12, presented as a representative independent claim (Compl. ¶38-39). Plaintiff also alleges infringement of at least claim 1 (Compl. ¶53).
- Essential elements of independent claim 12 include:
- A base station for a communication system where mobile stations transmit a channel estimation signal to their corresponding base station and to base stations in contiguous areas.
- The base station transmits data using a transmission beam that is directed to mobile stations in its area and not directed to adjacent mobile stations.
- The transmission is performed "on the basis of" three inputs: (1) the channel estimation signal from the in-area mobile station, (2) the channel estimation signals from adjacent mobile stations, and (3) an interference amount at those adjacent mobile stations (’803 Patent, col. 10:7-33).
- The complaint reserves the right to assert additional claims (Compl. ¶38).
U.S. Patent No. 10,484,976 - "Signaling, Procedures, User Equipment and Base Stations for Uplink Ultra Reliable Low Latency Communications," issued November 19, 2019
The Invention Explained
- Problem Addressed: The patent addresses the need for new signaling procedures to manage communications in systems with demanding performance requirements, such as the ultra-reliable low latency communications (URLLC) envisioned for 5G networks (’976 Patent, col. 1:17-23).
- The Patented Solution: The invention describes a method for a base station and user equipment (UE) to manage uplink data transmissions. The base station uses a Radio Resource Control (RRC) message to configure parameters like periodicity and numerology. It then uses a Downlink Control Information (DCI) format, transmitted on a physical control channel, to activate or deactivate a specific uplink transmission. The UE, in turn, provides confirmation using a Medium Access Control (MAC) Control Element (CE), which is identified by a specific Logical Channel Identifier (LCID) (’976 Patent, Abstract; Compl. ¶61).
- Technical Importance: This structured signaling protocol is designed to enable the efficient and reliable allocation of uplink resources required for time-sensitive applications like URLLC (Compl. ¶61).
Key Claims at a Glance
- The complaint asserts infringement of at least claim 2, presented as a representative independent claim directed to a base station apparatus (Compl. ¶64-65).
- Essential elements of independent claim 2 include:
- A base station with transmitting circuitry to send RRC messages for configuring periodicity and numerology.
- The transmitting circuitry sends a DCI format with a Cyclic Redundancy Check (CRC) scrambled by a "first RNTI" (Radio Network Temporary Identifier) to indicate activation/deactivation of an uplink transmission.
- The "first RNTI" is different from a Cell-RNTI and a semi-persistent scheduling C-RNTI.
- The base station has receiving circuitry to receive a confirmation MAC CE for both activation and deactivation.
- The confirmation MAC CE is identified by a MAC Protocol Data Unit (PDU) subheader with a specific LCID (’976 Patent, col. 39:13-60).
- The complaint reserves the right to assert additional claims (Compl. ¶64).
U.S. Patent No. 10,841,958 - "Access Node, a Method for an Access Node, a Wireless Terminal, and a Method for a Wireless Terminal," issued November 17, 2020 (Multi-Patent Capsule)
The Invention Explained
- Technology Synopsis: The patent addresses the inefficiency of network base stations periodically broadcasting all System Information Blocks (SIBs), which can waste radio resources, especially for non-essential information (’958 Patent, col. 1:34-58). The invention provides a system where an access node uses a "value tag" in a primary SIB (SIB1) to indicate whether the content of other, non-essential SIBs has changed, allowing those SIBs to be provided on-demand rather than being constantly broadcast (Compl. ¶89).
- Asserted Claims: The complaint asserts infringement of at least claim 1, presented as a representative claim (Compl. ¶92-93).
- Accused Features: The complaint alleges that T-Mobile’s 5G network, by complying with 3GPP standards for System Information (SI) management, infringes the ’958 Patent. Specifically, it points to the network's use of SIB1 to signal the availability of other SIBs, indicate whether they are provided by broadcast or on-demand, and use a "valueTag" to signal updates (Compl. ¶¶97-100).
III. The Accused Instrumentality
Product Identification
- The accused instrumentalities are T-Mobile's 5G Networks, including its "5G Ultra Capacity" and "5G Extended Range" services, and the network equipment (e.g., gNodeBs), software, and systems that enable their operation (Compl. ¶37, 63, 91).
Functionality and Market Context
- The complaint alleges the accused networks provide 5G wireless services throughout the United States and are marketed as "America's largest and fastest 5G network" (Compl. ¶8). The complaint includes a map from T-Mobile's website depicting its nationwide 5G coverage (Compl. p. 3). The networks are alleged to operate in both 5G Non-Standalone (NSA) and Standalone (SA) configurations and comply with the technical specifications of the 3rd Generation Partnership Project (3GPP) 5G Standard (Compl. ¶30, 31).
IV. Analysis of Infringement Allegations
U.S. Patent No. 8,576,803 Infringement Allegations
| Claim Element (from Independent Claim 12) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A base station for a communication system that includes a plurality of said base stations and mobile subscriber stations... | T-Mobile's 5G networks comprise a plurality of base stations (gNodeBs or gNBs) and support mobile subscriber stations (e.g., smartphones). The complaint includes a diagram of a 5G network radio access network (RAN) architecture (Compl. p. 18, Fig. 4.1-1). | ¶43-44 | col. 10:7-13 |
| ...each mobile subscriber station in each area transmitting a channel estimation signal...to base stations corresponding to areas contiguous to the area... | Mobile devices on the 5G network transmit a Sounding Reference Signal (SRS), which functions as a channel estimation signal, to both their serving base station and neighboring base stations. | ¶46 | col. 10:14-19 |
| ...said base station transmits data...using a transmission beam that is directed to the mobile subscriber stations in the corresponding area and is not directed to adjacent mobile subscriber stations... | T-Mobile's gNBs allegedly use beamforming techniques to direct energy toward a target user while creating nulls toward other users to avoid interference. The complaint provides a diagram illustrating this concept of desired beam direction and null direction (Compl. p. 21, Fig. 10). | ¶48 | col. 10:20-26 |
| ...the data being transmitted...on the basis of the channel estimation signal received from the mobile subscriber station in an area corresponding to said base station... | The gNB calculates downlink precoding weights for beamforming based on the SRS received from the target mobile station within its own cell. | ¶49 | col. 10:27-29 |
| ...the channel estimation signals received from the adjacent mobile subscriber stations... | Because SRSs are reused across cells, a gNB receives SRSs from neighboring cells (pilot contamination), which it allegedly uses to perform channel estimation for those adjacent stations to enable nulling. | ¶51 | col. 10:30-33 |
| ...an interference amount at the adjacent mobile subscriber stations... | The network determines interference levels from adjacent cells using measurements on Channel State Information – Interference Measurement (CSI-IM) resources. | ¶52 | col. 10:34-36 |
Identified Points of Contention
- Technical Questions: A central evidentiary question may be whether T-Mobile's network actually uses the SRS received from adjacent cells to actively calculate and form nulls toward those cells, as required by the claim, or if it employs a more general interference mitigation technique that does not map onto the claim's specific "on the basis of" language.
- Scope Questions: The dispute may turn on the construction of "on the basis of." Does this phrase require the enumerated signals and interference amount to be direct inputs into a beamforming calculation, or can it be satisfied by a system that merely accounts for them in a broader resource scheduling or interference management algorithm?
U.S. Patent No. 10,484,976 Infringement Allegations
| Claim Element (from Independent Claim 2) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A base station apparatus that communicates with a user equipment (UE)... | T-Mobile's 5G base station devices (gNBs) communicate with UEs (e.g., smartphones) within the network architecture. | ¶69 | col. 39:13-15 |
| ...transmitting circuitry configured to transmit a radio resource control (RRC) message comprising first information used for configuring a periodicity... | The accused network allegedly uses RRC signaling to configure "Type 2" uplink grants, which includes configuring a "periodicity" parameter for the grant. | ¶70-71 | col. 39:16-19 |
| ...the transmitting circuitry configured to transmit a RRC message comprising second information used for configuring a numerology... | The accused network allegedly transmits RRC information elements, such as the "BWP" element, which contains a "subcarrierSpacing" parameter that corresponds to the claimed "numerology." | ¶72 | col. 39:20-22 |
| ...transmit...a DCI format with CRC scrambled by a first RNTI...being different from a Cell-RNTI...and a semi-persistent scheduling C-RNTI... | The network allegedly uses a DCI format scrambled by a Configured Scheduling RNTI (CS-RNTI) to activate and deactivate uplink grants, where this CS-RNTI is distinct from the C-RNTI. | ¶73-74 | col. 39:23-38 |
| ...receiving circuitry configured to receive confirmation information Medium Access Control (MAC) Control Element (CE)...for...activation...and...deactivation... | Per 3GPP standards, the UE's MAC entity is allegedly triggered to provide a "configured uplink grant confirmation MAC CE" upon receiving a DCI indicating either activation or deactivation of a Type 2 grant. | ¶76, 79 | col. 39:39-50 |
| ...the confirmation information MAC CE...is identified by a MAC protocol data unit (MAC PDU) subheader with a logical channel identifier (LCID)... | The complaint alleges that, per 3GPP TS 38.321, the "Configured Grant Confirmation MAC CE" is identified by a MAC subheader with a specific LCID value. The complaint includes a table from the standard showing this mapping (Compl. p. 38, Table 6.2.1-2). | ¶80 | col. 39:51-60 |
Identified Points of Contention
- Scope Questions: The infringement theory rests almost entirely on the allegation that T-Mobile's network complies with 3GPP standards. A potential point of contention is whether mere standards compliance equates to infringement of every claim limitation, or if there are distinctions between the standard's implementation and the patent's specific claim language. For instance, does the "first RNTI" of the claim precisely read on the "CS-RNTI" of the standard?
- Technical Questions: What evidence demonstrates that the base station's "receiving circuitry" actively "receives" the MAC CE as claimed? The complaint alleges the standard "triggers" a confirmation, raising the question of whether this trigger results in a transmission that is "received" in the manner required by the patent.
V. Key Claim Terms for Construction
'803 Patent, Claim 12
- The Term: "on the basis of"
- Context and Importance: This term is critical as it defines the required link between three distinct information sources (local SRS, adjacent SRS, adjacent interference) and the resulting transmission beam. The infringement case for the adjacent-cell limitations hinges on whether T-Mobile's system uses this information in the manner contemplated by the claim. Practitioners may focus on this term because its interpretation—whether it requires direct calculation versus general consideration—will likely determine the outcome of the infringement analysis.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent's general statements in the background about the goal of avoiding interference could support an interpretation where any system that considers these factors meets the limitation (’803 Patent, col. 2:1-2).
- Evidence for a Narrower Interpretation: The detailed description may contain specific formulas or block diagrams that depict these three information sources as direct inputs to a "weight generator" or similar component, suggesting a more restrictive, computational relationship (’803 Patent, col. 4:1-12).
'976 Patent, Claim 2
- The Term: "receiving circuitry configured to receive confirmation information"
- Context and Importance: The claim requires the base station to "receive" a MAC CE confirmation. The complaint's evidence points to a 3GPP standard where a PDCCH message triggers a "configured uplink grant confirmation" at the UE (Compl. ¶76). The dispute will likely center on what happens after the trigger and whether that constitutes "receiving confirmation information" at the base station as claimed.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification may describe the confirmation in functional terms, suggesting that any process which informs the base station that the UE has processed the DCI would suffice, even an internal state update triggered by the UE's subsequent actions.
- Evidence for a Narrower Interpretation: The patent’s flowchart in Figure 21 explicitly shows a step where the base station apparatus "Receive[s], from the user equipment, confirmation information Medium Access Control (MAC) Control Element (CE)" (’976 Patent, Fig. 21, element 2106). This figure strongly supports an interpretation requiring an actual transmission from the UE to the base station.
VI. Other Allegations
- Indirect Infringement: The complaint alleges both induced and contributory infringement for all asserted patents. The inducement theory is based on T-Mobile supplying its 5G network and services to customers with the knowledge and intent that their use (e.g., operating a 5G device on the network) will directly infringe the patents, supported by T-Mobile's advertising and user instructions (Compl. ¶55-56, 83-84, 107-108).
- Willful Infringement: Willfulness is alleged based on T-Mobile’s knowledge of the patents continuing from at least the filing date of the original complaint in this action. This constitutes an allegation of post-suit willfulness (Compl. ¶54, 82, 106, 111(e)).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of technical operation: For the ’803 Patent, does T-Mobile's 5G network use channel data from adjacent cells to actively compute and steer nulls in its transmission beams, as the claim appears to require, or does it use a different, more generalized method of interference mitigation that falls outside the patent's scope?
- A central legal question will be one of standards equivalence: For the ’976 and ’958 Patents, where the infringement allegations rely heavily on compliance with 3GPP standards, can Plaintiff prove that the standardized operations for uplink grant management and system information broadcasting are functional equivalents that meet every limitation of the asserted claims, or will Defendant demonstrate material operational differences?
- A key evidentiary question will be one of definitional scope: Will the term "on the basis of" in the '803 Patent be construed to require a direct computational link, and will "receive confirmation" in the '976 Patent be construed to require an explicit message transmission from the user device to the base station? The construction of these key phrases will likely be determinative for infringement.