Tot Power Control SL v. T-Mobile US Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: TOT Power Control, SL. (Spain)
  • Defendant: T-Mobile USA, Inc. (Delaware)
  • Plaintiff’s Counsel: DINOVO PRICE LLP
• Case Identification: 6:21-cv-00109, W.D. Tex., 01/29/2026
• Venue Allegations: Plaintiff alleges venue is proper in the Western District of Texas because Defendant maintains a regular and established place of business in the District, including retail stores and CDMA-based wireless network infrastructure such as cellular towers.
• Core Dispute: Plaintiff alleges that Defendant’s WCDMA-based wireless networks infringe two patents related to methods for managing power control in mobile communications to improve efficiency and maintain call quality.
• Technical Context: The patents address outer loop power control, a fundamental process in 3G/WCDMA cellular technology used to manage the signal-to-interference ratio (SIR), which directly impacts network capacity and connection reliability.
• Key Procedural History: The complaint alleges that Plaintiff shared the patented techniques with Defendant's base station equipment suppliers, including Intervenors Nokia and Ericsson. Plaintiff also notes that it served infringement contentions on Defendant on December 19, 2025.

Case Timeline

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 7,496,376 - "Outer Loop Power Control Method and Apparatus for Wireless Communications Systems," issued February 24, 2009

The Invention Explained

• Problem Addressed: In WCDMA networks, conventional outer loop power control (OLPC) adjusts a target Signal-to-Interference Ratio (SIR_target) based on the measured Block Error Rate (BLER). This process is slow, especially for high-quality connections, causing the system to react sluggishly to changing channel conditions (fading), which can lead to using more power than necessary and reducing overall network capacity Compl. ¶12 ’376 Patent, col. 3:1-20
• The Patented Solution: The invention proposes a more adaptive OLPC method that supplements the slow BLER-based adjustments. It calculates "fading margins" based on "outage probabilities" and uses a "dynamic adjusting function" to map these faster-reacting, channel-condition metrics to the desired quality of service objective, allowing the SIR_target to adapt more quickly and efficiently to the radio environment (Compl. ¶16; ’376 Patent, Abstract, col. 6:1-12). The complaint includes a figure illustrating how the convergence speed of the SIR_target slows as the target quality (low BLER) increases, highlighting the problem the patent seeks to solve Compl., p. 7
• Technical Importance: This approach allows for more precise power control, which is intended to reduce wasted power, minimize interference, and thereby increase the capacity and call quality of the wireless network (Compl. ¶12, ¶20).

Key Claims at a Glance

• The complaint asserts independent apparatus Claim 6 Compl. ¶28
• Essential elements of Claim 6 include:
  • An apparatus with at least one programmable electronic device operable to perform steps including:
  • establishing a target block error rate (BLER_target);
  • calculating an estimate of a desired signal to interference ratio (SIR_rec) and of fading parameters in a channel;
  • estimating fading margins associated with outage probabilities;
  • indicating a status of data blocks based on a Cyclic Redundancy Code (CRC) check; and
  • establishing a target SIR (SIR_target) based on the data block status, the fading margins, and the target BLER, by means of a "dynamic adjusting function which performs a mapping" between a quality criterion based on outage probabilities and a quality criterion based on the target BLER.
• The complaint reserves the right to assert other claims, including Claim 1 Compl. ¶26

U.S. Patent No. 7,532,865 - "Outer Loop Power Control Method and Device for Wireless Communications Systems," issued May 12, 2009

The Invention Explained

• Problem Addressed: The patent targets a specific OLPC problem known as "wind-up." This occurs when poor channel conditions (e.g., a user entering an elevator) cause the SIR_target to increase dramatically. When conditions improve, the process of reducing, or "unwinding," the SIR_target back to a normal level using conventional methods is extremely slow. This prolonged period of an unnecessarily high SIR_target creates excess interference, wasting network capacity Compl. ¶12 ’865 Patent, col. 2:51-col. 3:17 The complaint provides a diagram illustrating the stepwise adjustment of SIR_target in response to block errors, which forms the basis of the wind-up problem Compl., p. 6
• The Patented Solution: The invention is a method for actively managing the "unwinding" process. It involves detecting the start of the outer loop wind-up, setting a specific SIR_target during wind-up, and, crucially, detecting the start of the unwinding phase. Upon detecting the start of unwinding, the method modifies the SIR_target to match the value it had just prior to the wind-up event, thereby avoiding the slow, conventional reduction process (Compl. ¶19; ’865 Patent, Abstract, Claim 1).
• Technical Importance: This technique is designed to drastically shorten the unwinding time, which reduces interference, increases system capacity, and improves the quality of wireless connections by, for example, reducing dropped calls Compl. ¶19

Key Claims at a Glance

• The complaint asserts independent method Claim 1 Compl. ¶45
• Essential elements of Claim 1 include:
  • estimating a received SIR (SIR_rec);
  • setting a target SIR (SIR_target) close to the required SIR during normal operation;
  • detecting a start of the outer loop wind-up;
  • setting a specific SIR_target during the wind-up; and
  • detecting a start of the outer loop unwinding, wherein the SIR_target is modified at the start of unwinding to match its value from the normal mode just prior to the wind-up.
• The complaint reserves the right to assert other claims, including Claim 5 Compl. ¶43

III. The Accused Instrumentality

Product Identification

Defendant's WCDMA-based wireless networks, which include infrastructure components such as base stations (Node-Bs) and Radio Network Controllers (RNCs) (Compl. ¶28, ¶45).

Functionality and Market Context

The complaint alleges these network components perform outer loop power control as part of their operation in compliance with the 3GPP UMTS cellular standard Compl. ¶30 The relevant functionality is the management of the SIR_target value to control transmission power for mobile devices. The complaint asserts that implementing the patented techniques provides Defendant with "significant capacity gains" in its wireless networks Compl. ¶20

IV. Analysis of Infringement Allegations

’376 Patent Infringement Allegations

• Identified Points of Contention:
  • Scope Questions: A central question may be whether the standard OLPC operations in Defendant's equipment, which are designed to comply with the 3GPP standard, meet the specific limitations of Claim 6. The defense may argue that any adjustments are dictated by the standard and do not practice the claimed "mapping" between outage-based and BLER-based quality criteria.
  • Technical Questions: What evidence does the complaint provide that Defendant's system specifically estimates "fading margins" based on "outage probabilities" and uses a "dynamic adjusting function" to map them, as distinct from a conventional algorithm that simply considers multiple inputs, including CRC errors, to adjust the SIR_Target? The allegations are described at a high level of functionality (Compl. ¶33, ¶35).

’865 Patent Infringement Allegations

• Identified Points of Contention:
  • Scope Questions: Does the accused system perform an affirmative step of "detecting a start...of the outer loop unwinding" and then "modifying" the SIR_Target as a distinct, claimed action? A defendant may argue that the observed behavior is simply the natural result of a standard power control loop recovering from a period of high error, not the practice of a specific, patented multi-step method.
  • Technical Questions: How does the accused system technically "match" the post-unwinding SIR_Target to its pre-wind-up value? The complaint alleges it is adjusted to a "value consistent with" the prior value, which raises the question of how closely it must match to meet the claim limitation Compl. ¶50

V. Key Claim Terms for Construction

’376 Patent (Claim 6)

• The Term: "dynamic adjusting function which performs a mapping between a quality criterion based on the outage probabilities . . . and the quality criterion based on the target block error rate"
• Context and Importance: This term appears to define the core novelty of the claim over conventional OLPC. Its construction will determine whether any algorithm that considers both outage-related and BLER-related factors infringes, or if a more specific implementation is required. Practitioners may focus on this term because infringement will depend on whether Defendant's standard-compliant equipment performs this specific type of "mapping."
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The claim uses broad functional language ("dynamic adjusting function," "mapping"), which could support an interpretation covering a range of algorithms that achieve the stated result Compl. ¶35
  • Evidence for a Narrower Interpretation: The specification provides a detailed embodiment of the function as a two-layer neural network, which is a specific and complex structure ’376 Patent, FIG. 5 col. 6:17-51 A party could argue the claim scope should be guided by this detailed disclosure.

’865 Patent ([Claim 1](https://ex:cit:16))

• The Term: "detecting a start (403) of the outer loop unwinding"
• Context and Importance: This step is the trigger for the claimed rapid SIR_target modification. The case may turn on whether the accused system performs an affirmative "detection" action or if the system's recovery from wind-up is merely an inherent, automatic behavior of the underlying power control standard.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The specification does not mandate a particular detection method, suggesting any process that identifies the end of the wind-up condition (e.g., by observing a cessation of CRC errors) could meet the limitation Compl. ¶50
  • Evidence for a Narrower Interpretation: The patent figures explicitly label a point in time, "403," as the start of unwinding, and the text describes this as the point where the received SIR is again able to reach the target SIR. This may support an argument that "detecting" requires a specific determination tied to this technical condition, not just a passive observation of improved signal quality ’865 Patent, FIG. 4 col. 7:19-25

VI. Other Allegations

• Indirect Infringement: The complaint focuses on direct infringement by Defendant T-Mobile through its use of the accused WCDMA networks (Compl. ¶27, ¶44). While it names Nokia and Ericsson as suppliers of the accused base stations and RNCs, it does not plead separate counts for indirect infringement in this complaint (Compl. ¶28, ¶45).
• Willful Infringement: The complaint alleges willfulness based on Defendant's knowledge of the patents "at least since the filing and service of TOT's Complaint" (Compl. ¶38, ¶53). The allegations of egregious, knowing, and intentional infringement appear to be based on continued use of the accused networks after receiving notice of the lawsuit (Compl. ¶40, ¶55).

VII. Analyst’s Conclusion: Key Questions for the Case

• A core issue will be one of technical implementation vs. standards compliance: Does the evidence show that Defendant's network equipment, supplied by Nokia and Ericsson, performs the specific steps claimed in the patents—such as the '376 patent's "mapping" function and the '865 patent's "detecting...unwinding" step—or are the accused operations merely the conventional and required behavior of any system compliant with the 3GPP WCDMA standard?
• A key evidentiary question will be one of distinguishing method from effect: For the ’865 patent, the dispute will likely center on whether the accused system executes a discrete, patented method for rapidly resetting the SIR_target after a wind-up event, or whether the observed behavior is simply the natural and inherent result of a standard power control algorithm recovering from a period of high signal degradation.