Fleet Connect Solutions LLC v. Murata Mfg Co Ltd

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Fleet Connect Solutions LLC (Texas)
  • Defendant: Murata Manufacturing Co., Ltd (Japan) and Murata Electronics North America, Inc. (Texas/Georgia)
  • Plaintiff’s Counsel: Rozier Hardt McDonough PLLC
• Case Identification: 2:24-cv-00964, E.D. Tex., 11/21/2024
• Venue Allegations: Plaintiff alleges venue is proper based on Defendant Murata having a regular and established place of business in the district (Carrollton, Texas) where it allegedly commits acts of infringement. Venue over the foreign parent, Murata LTD, is alleged under 28 U.S.C. § 1391(c).
• Core Dispute: Plaintiff alleges that Defendant’s Wi-Fi® and Bluetooth® wireless communication modules infringe seven patents related to foundational technologies for improving the performance, reliability, and efficiency of wireless data transmission.
• Technical Context: The patents address core challenges in modern wireless standards like IEEE 802.11 (Wi-Fi), including correcting signal errors in OFDM systems, mitigating interference between co-located radios, and managing data streams in MIMO systems.
• Key Procedural History: The complaint does not allege any prior litigation, Inter Partes Review (IPR) proceedings, or licensing history relevant to the asserted patents or accused products.

Case Timeline

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

U.S. Patent No. 6,549,583 - "Optimum Phase Error Metric for OFDM Pilot Tone Tracking in Wireless LAN"

• Issued: April 15, 2003

The Invention Explained

• Problem Addressed: The patent describes that in wireless communication systems like WLANs, phase noise from a radio receiver's local oscillators can corrupt the signal, degrading performance and limiting data rates, particularly with complex modulations like 64-QAM. This problem is exacerbated in highly integrated, low-cost chips where high-performance radio components are difficult to implement (’583 Patent, col. 1:19-51).
• The Patented Solution: The invention proposes a method to compensate for this radio-level hardware deficiency using digital signal processing. Instead of relying on a single signal, the system uses complex signal measurements from a plurality of known "pilot tones" embedded in the OFDM signal to create a more robust, "aggregate" estimate of the phase error. This estimation is guided by a "maximum likelihood" approach, which is a statistical method for finding the most probable cause (the phase error) of the observed signals ('583 Patent, Abstract; col. 2:5-9).
• Technical Importance: This technique allows for the use of less expensive, lower-performance radio hardware in high-data-rate wireless devices by shifting the complex task of phase noise correction from the analog radio domain to the digital baseband processor (’583 Patent, col. 4:5-14).

Key Claims at a Glance

• The complaint asserts at least independent claim 1 (Compl. ¶24).
• Claim 1 requires:
  • A method for pilot phase error estimation in an orthogonal frequency division multiplexed (OFDM) receiver.
  • Determining pilot reference points from a plurality of pilots in an OFDM preamble waveform.
  • Estimating an aggregate phase error for a subsequent data symbol using complex signal measurements from those pilots.
  • Wherein the estimation step performs a "maximum likelihood-based estimation."

U.S. Patent No. 6,633,616 - "OFDM Pilot Tone Tracking for Wireless LAN"

• Issued: October 14, 2003

The Invention Explained

• Problem Addressed: Like the ’583 Patent, this invention addresses performance degradation in OFDM systems caused by phase noise, particularly the processing delays that can limit the effectiveness of phase correction feedback loops (’616 Patent, col. 17:58-18:10).
• The Patented Solution: The invention discloses a specific system architecture to speed up phase error correction. It describes performing the pilot phase error estimation in a separate processing path that runs in parallel to the main Fast Fourier Transform (FFT) processing path used for demodulating the actual data. This parallel architecture allows the phase error for a given data symbol to be calculated and corrected for before the main data processing for that same symbol is completed, reducing latency in the tracking loop (’616 Patent, Abstract; col. 18:38-48).
• Technical Importance: By reducing the processing delay for phase correction, this parallel architecture enables a more responsive, wider bandwidth tracking loop, which can better track and compensate for more rapid phase noise fluctuations (’616 Patent, col. 23:35-41).

Key Claims at a Glance

• The complaint asserts at least independent claim 12 (Compl. ¶32).
• Claim 12 requires:
  • A method for pilot phase error estimation in an OFDM receiver.
  • Determining pilot reference points from a preamble.
  • Processing the preamble with an FFT in a parallel path.
  • Determining a phase error estimate of a subsequent OFDM symbol.
  • Processing the subsequent symbol with the FFT in the parallel path.
  • Wherein the step of determining the phase error estimate is completed prior to the completion of the FFT processing of that subsequent symbol.

U.S. Patent No. 7,058,040 - "Channel Interference Reduction"

• Issued: June 6, 2006 (Compl. ¶35)
• Technology Synopsis: The patent addresses interference between two different wireless communication media that operate in overlapping frequency bands, such as Wi-Fi and Bluetooth in the 2.4 GHz band. The solution involves computing and allocating time-division multiple access (TDMA) time-slots to be shared between the two media and dynamically adjusting the number of slots assigned to each to maintain a desired level of service, thereby preventing them from transmitting simultaneously and interfering with each other (’040 Patent, col. 2:3-12).
• Asserted Claims: At least independent claim 1 (Compl. ¶40).
• Accused Features: The complaint alleges the accused products perform a method for data transmission over first and second media that overlap in frequency by computing, allocating, and dynamically adjusting shared TDMA time-slot channels to remain within limits of a desired service level (Compl. ¶40).

U.S. Patent No. 7,260,153 - "Multi Input Multi Output Wireless Communication Method and Apparatus Providing Extended Range and Extended Rate Across Imperfectly Estimated Channels"

• Issued: August 21, 2007 (Compl. ¶43)
• Technology Synopsis: The technology addresses the problem of "cross-talk" interference between parallel data sub-streams in a multiple-input multiple-output (MIMO) wireless system, which arises when the communication channel is not perfectly known. The solution involves defining a specific "channel matrix metric" of cross-talk signal-to-noise ratio (SNR), estimating this metric, and performing a singular value decomposition (SVD) mathematical operation on it to calculate a measure of the crosstalk, enabling more robust communication (’153 Patent, Abstract; col. 4:39-56).
• Asserted Claims: At least independent claim 1 (Compl. ¶48).
• Accused Features: The accused products are alleged to perform a method of evaluating a MIMO channel by defining and estimating a channel matrix metric of cross-talk SNR, performing an SVD to calculate estimated channel singular values, and using these values to calculate a crosstalk measure for the sub-streams (Compl. ¶48).

U.S. Patent No. 7,656,845 - "Channel Interference Reduction"

• Issued: February 2, 2010 (Compl. ¶51)
• Technology Synopsis: Related to the ’040 patent, this invention describes a system for managing communication over two different media. The system includes a first and second transceiver and an allocation unit that dynamically allocates data channels between the media based on a desired level of service. A key feature is the configuration to retry transmitting a packet at a lower data rate if a prior transmission is not acknowledged (’845 Patent, Abstract).
• Asserted Claims: At least independent claim 12 (Compl. ¶56).
• Accused Features: The complaint alleges the accused products provide a system with first and second transceivers, a feature for retrying packet transmission at a lower rate if not acknowledged, and an allocation unit for dynamically allocating data channels between the two media based on a service level (Compl. ¶56).

U.S. Patent No. 7,742,388 - "Packet Generation Systems and Methods"

• Issued: June 22, 2010 (Compl. ¶59)
• Technology Synopsis: The patent describes a method to increase the data rate of a wireless packet. The solution involves starting with a standard packet that has a preamble containing a first and a second training symbol, and then "increasing the size of the packet by adding subcarriers to the second training symbol" to create an extended packet, where the second training symbol now has more subcarriers than the first (’388 Patent, Abstract; col. 2:15-26).
• Asserted Claims: At least independent claim 1 (Compl. ¶64).
• Accused Features: The complaint alleges the accused products perform a method of generating a packet with a preamble having two training symbols, increasing the packet size by adding subcarriers to the second training symbol to make it larger than the first, and transmitting this extended packet (Compl. ¶64).

U.S. Patent No. 8,005,053 - "Channel Interference Reduction"

• Issued: August 23, 2011 (Compl. ¶74)
• Technology Synopsis: The patent describes a method for a device with multiple transceivers for different wireless protocols to manage data. The solution involves selecting one wireless protocol for transmission, taking data formatted for an unselected protocol, and encoding that data into the selected protocol's format. The device then transmits the combined, encoded data using the transceiver corresponding to the selected protocol (’053 Patent, Abstract).
• Asserted Claims: At least independent claim 10 (Compl. ¶79).
• Accused Features: The complaint alleges the accused products perform a method where a device with multiple transceivers selects one protocol, encodes data from an unselected protocol into the selected protocol, and transmits the encoded data using the transceiver for the selected protocol (Compl. ¶79).

III. The Accused Instrumentality

Product Identification

• The complaint identifies a lengthy list of Wi-Fi®/Bluetooth® Modules by Murata part number (e.g., LBEE5XV1XA-540) and generally accuses any other Murata products with "substantially similar functionality" (Compl. ¶15).

Functionality and Market Context

• The complaint alleges that the Accused Products are computing devices that "perform wireless communications and methods" compliant with various protocols, including Bluetooth and IEEE 802.11 standards such as 802.11ac and 802.11n (Compl. ¶16). These modules are components used to provide wireless connectivity in a wide array of consumer and industrial electronics.

IV. Analysis of Infringement Allegations

No probative visual evidence provided in complaint.

The complaint refers to "Evidence of Use Charts" attached as exhibits for each asserted patent, but these exhibits were not included with the complaint document (Compl. ¶¶ 24, 32, 40, 48, 56, 64, 79). In their absence, the infringement theory is drawn from the narrative allegations in the complaint body.

U.S. Patent No. 6,549,583 Infringement Allegations

Narrative Summary

• The complaint alleges that the Accused Products infringe at least claim 1 by performing a method of pilot phase error estimation in an OFDM receiver. The allegations track the claim language, stating the products determine pilot reference points from a preamble and then estimate an aggregate phase error for subsequent data symbols using complex signal measurements from those pilots. The central technical allegation is that this estimation step comprises "performing a maximum likelihood-based estimation" (Compl. ¶24).

Identified Points of Contention

• Technical Question: What evidence demonstrates that the algorithm used in the Accused Products is specifically "maximum likelihood-based," as opposed to another type of estimation algorithm? The complaint’s allegation is conclusory and lacks specific details about the accused algorithm's operation that would map to the mathematical definitions of maximum likelihood estimation provided in the patent.

U.S. Patent No. 6,633,616 Infringement Allegations

Narrative Summary

• The complaint alleges the Accused Products infringe at least claim 12 by performing a pilot phase error estimation method that involves parallel processing. It alleges the products determine pilot reference points from a preamble while processing that same preamble with an FFT in a parallel path. It further alleges that for a subsequent data symbol, the phase error estimate is determined while that symbol is processed by the FFT in the parallel path, with the key assertion being that the "phase error estimate step is completed prior to the completion of the processing of the subsequent OFDM symbol with the fast Fourier transform" (Compl. ¶32).

Identified Points of Contention

• Technical Question: What evidence substantiates the specific internal timing relationship required by the claim? Proving that one internal processing step (phase estimation) finishes before another (FFT processing) on the same data symbol will likely require access to internal design documents or sophisticated technical analysis of the accused chipsets.

V. Key Claim Terms for Construction

Term from the ’583 Patent: "maximum likelihood-based estimation"

• Context and Importance: This term appears to be the primary technical limitation defining the invention of claim 1. The infringement dispute may center on whether the algorithm implemented in Murata's modules meets the specific mathematical definition of this term or if it employs a different, non-infringing estimation method. Practitioners may focus on this term because it recites a specific, well-defined mathematical approach, not a generic estimation.
• Intrinsic Evidence for a Broader Interpretation: The specification describes the goal as maximizing a log-likelihood function (’583 Patent, col. 11:63-65). An argument for a broader scope could suggest that any estimation method that is guided by or approximates this principle is "based on" maximum likelihood.
• Intrinsic Evidence for a Narrower Interpretation: The specification provides specific equations that embody the method, such as Equation (14), which defines the estimate as the arctangent of a ratio of summed and weighted I/Q signal components (’583 Patent, col. 12:40-44). An argument for a narrower scope could be that an accused method must implement or be mathematically equivalent to these specific disclosed formulas.

Term from the ’616 Patent: "processing, in a parallel path"

• Context and Importance: The novelty of claim 12 appears to reside in its architectural requirement for concurrent processing. The definition of "parallel path" will be critical to determining infringement. The question for the court may be whether this requires physically distinct hardware circuits or if it can be satisfied by logically separate processes that are time-multiplexed on a single processor, so long as the claim's timing requirement is met.
• Intrinsic Evidence for a Broader Interpretation: The patent's abstract and summary focus on the outcome—completing the phase estimation before the FFT finishes—rather than on a specific hardware layout. This could support an interpretation where "parallel path" refers to any implementation, physical or logical, that achieves this required timing relationship (’616 Patent, Abstract).
• Intrinsic Evidence for a Narrower Interpretation: Figures in the patent, such as FIG. 8, depict the "Pilot Phase Error Metric" block (808) and the "FFT" block (304) as distinct functional blocks receiving input from a common point but proceeding separately. This could support an argument that the claims require architecturally distinct processing paths.

VI. Other Allegations

Indirect Infringement

• The complaint alleges indirect infringement (inducement and contributory) only for U.S. Patent No. 7742388. Inducement is alleged based on Defendant providing instructions and advertising that guide users to use the Accused Products in an infringing manner (Compl. ¶65). Contributory infringement is alleged on the basis that the products contain special features that are material to the invention and not staple articles of commerce (Compl. ¶66).

Willful Infringement

• A claim for willful infringement is made only with respect to the ’388 Patent. The allegation is based on alleged knowledge of the patent since at least the filing of the complaint (post-suit knowledge) and an alleged corporate policy of not reviewing patents of others, constituting willful blindness (Compl. ¶¶ 67-68, 70).

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

1. Evidentiary Burden for Algorithmic Equivalence: A core issue for the ’583 patent will be one of technical proof: can Plaintiff produce evidence demonstrating that the algorithms within Murata's accused products perform a "maximum likelihood-based estimation," as defined by the patent, or do they use a functionally different, non-infringing estimation technique?
2. Architectural Proof of Processing Timing: For the ’616 patent, a central question will be one of internal operation: what evidence will be required to prove the specific timing relationship that the phase error estimation for a data symbol is completed before the FFT processing of that same symbol is finished, as required by the claim?
3. Definitional Scope of "Media" and "Channels": For the patents related to "Channel Interference Reduction" (’040, ’845, ’053), a key issue will be one of claim construction: how will terms like "first and second media" and "dynamically adjusting a number of timeslot channels" be construed in the context of highly integrated, single-chip Wi-Fi/Bluetooth modules, and do the accused products' co-existence mechanisms fall within that scope?