DCT

2:22-cv-00066

GenghisComm Holdings LLC v. ASUSTeK Computer Inc

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Key Events
Amended Complaint

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:22-cv-00066, E.D. Tex., 02/21/2023
  • Venue Allegations: Venue is alleged to be proper on the basis that Defendant is not a resident of the United States and may therefore be sued in any judicial district.
  • Core Dispute: Plaintiff alleges that Defendant’s 4G LTE and 5G-capable mobile devices, including smartphones and tablets, infringe five U.S. patents related to signal processing techniques for wireless communications, particularly concerning Orthogonal Frequency Division Multiplexing (OFDM) and Single-Carrier Frequency-Division Multiple Access (SC-FDMA).
  • Technical Context: The technology at issue involves methods for generating and processing signals for uplink transmission in modern wireless networks, designed to improve efficiency and reduce the peak-to-average power ratio (PAPR) of the transmission signal.
  • Key Procedural History: The complaint alleges that Defendant has been on notice of U.S. Patent Nos. 9,768,842, 10,200,227, and 10,389,568 since at least November 19, 2020, following a letter from Plaintiff’s counsel that included claim charts. Notice for U.S. Patent Nos. 11,075,786 and 11,223,508 is alleged to have been provided by the filing of the complaint itself.

Case Timeline

Date Event
2002-05-14 Earliest Priority Date for all Patents-in-Suit
2017-09-19 U.S. Patent No. 9,768,842 Issued
2019-02-05 U.S. Patent No. 10,200,227 Issued
2019-08-20 U.S. Patent No. 10,389,568 Issued
2020-11-19 Plaintiff sent pre-suit notice letter to Defendant regarding the ’842, ’227, and ’568 Patents
2021-07-27 U.S. Patent No. 11,075,786 Issued
2022-01-11 U.S. Patent No. 11,223,508 Issued
2022-11-07 Plaintiff's counsel purchased an accused Asus Zenfone 9 in the U.S.
2023-02-21 First Amended Complaint Filed

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

U.S. Patent No. 9,768,842 - "Pre-coding in multi-user MIMO"

  • Patent Identification: U.S. Patent No. 9,768,842, "Pre-coding in multi-user MIMO," issued September 19, 2017.

The Invention Explained

  • Problem Addressed: The patent's background describes challenges in wireless communication systems, including managing interference between users and the high peak-to-average power ratio (PAPR) inherent in Orthogonal Frequency Division Multiplexing (OFDM) signals, which can lead to inefficient power amplifier usage. (’842 Patent, col. 1:49-55; col. 2:5-12).
  • The Patented Solution: The invention proposes a pre-coder for a transmitter that uses a Discrete Fourier Transform (DFT) spreader. This spreader applies Fourier coefficients to data symbols before they are modulated onto OFDM subcarriers. This process, which mirrors the principles of Single-Carrier Frequency-Division Multiple Access (SC-FDMA), is described as generating a transmission signal with a reduced PAPR. (’842 Patent, Abstract; col. 6:50-65).
  • Technical Importance: Reducing a signal's PAPR allows mobile devices to use more power-efficient and less costly amplifiers, which is a critical consideration for battery life and device manufacturing costs in mass-market electronics. (Compl. ¶70).

Key Claims at a Glance

  • The complaint asserts independent claim 1 and dependent claims 2, 3, 4, 7, 8, and 9. (Compl. ¶¶64, 77, 88, 96, 105, 113, 121).
  • Claim 1 requires:
    • An OFDM transmitter, comprising:
    • an OFDM spreader configured to spread a plurality of data symbols with Fourier coefficients to generate a DFT-spread data signal;
    • a mapper configured to map the DFT-spread data signal to a plurality of OFDM subcarriers; and
    • an OFDM modulator configured to modulate the DFT-spread data signal onto the plurality of OFDM subcarriers to produce an OFDM transmission signal comprising a superposition of the OFDM subcarriers, wherein the OFDM spreader is configured to provide the superposition with a reduced peak-to-average power ratio.

U.S. Patent No. 10,200,227 - "Pre-coding in multi-user MIMO"

  • Patent Identification: U.S. Patent No. 10,200,227, "Pre-coding in multi-user MIMO," issued February 5, 2019.

The Invention Explained

  • Problem Addressed: The patent addresses the same technical problems as its parent ’842 Patent, namely the spectral efficiency limitations caused by inter-cell interference and the high PAPR of OFDM signals. (’227 Patent, col. 2:5-12).
  • The Patented Solution: This patent claims an apparatus comprising a processor and memory with instructions to execute a similar SC-FDMA signal generation process. The instructions direct the processor to perform an invertible transform (like a DFT) on data symbols, map the resulting spread symbols to a larger set of OFDM subcarriers, and then perform an inverse transform (IDFT) to generate the final time-domain signal. The patent states that this process is configured to reduce the PAPR of the resulting signal superposition. (’227 Patent, Abstract; col. 7:5-10).
  • Technical Importance: The claimed method is central to the 4G LTE uplink standard (SC-FDMA), which was designed to give mobile devices the benefits of OFDM (like robustness to multipath) while avoiding the power consumption penalty associated with high PAPR. (Compl. ¶¶132, 136).

Key Claims at a Glance

  • The complaint asserts independent claim 22 and dependent claims 24, 25, 26, and 28. (Compl. ¶¶130, 146, 154, 163, 171).
  • Claim 22 requires:
    • An apparatus comprising a processor and a non-transitory memory with instructions to:
    • perform an invertible transform on data symbols to generate N spread data symbols using complex-valued spreading codes;
    • map the N spread data symbols to at least N subcarriers from a plurality of M OFDM subcarriers; and
    • perform an M-point inverse discrete Fourier transform (IDFT) to generate a time-domain sequence comprising a superposition of the OFDM subcarriers, wherein the invertible transform is configured to provide the superposition with a reduced peak-to-average power ratio.

Multi-Patent Capsule: U.S. Patent No. 10,389,568 - "Single carrier frequency division multiple access baseband signal generation"

  • Patent Identification: U.S. Patent No. 10,389,568, "Single carrier frequency division multiple access baseband signal generation," issued August 20, 2019. (Compl. ¶49).
  • Technology Synopsis: This patent claims an apparatus and method for generating an SC-FDMA baseband signal. It describes dividing a block of complex-valued symbols into sets, applying transform precoding to each set, and then generating a final OFDM signal, with the transform precoding configured to create a superposition of subcarriers with a reduced PAPR. (’568 Patent, Abstract).
  • Asserted Claims: The complaint asserts independent claim 24 and dependent claims 25, 26, 29, 32, 33, 34, and 44. (Compl. ¶¶179, 193, 203, 211, 220, 230, 239, 247).
  • Accused Features: The complaint alleges infringement by the accused devices' processors and memory, which are alleged to store and execute instructions for processing LTE physical channel uplink communications consistent with the LTE standard, including dividing symbols into sets for SC-FDMA processing and applying transform precoding. (Compl. ¶¶181-185).

Multi-Patent Capsule: U.S. Patent No. 11,075,786 - "Multicarrier sub-layer for direct sequence channel and multiple-access coding"

  • Patent Identification: U.S. Patent No. 11,075,786, "Multicarrier sub-layer for direct sequence channel and multiple-access coding," issued July 27, 2021. (Compl. ¶50).
  • Technology Synopsis: This patent describes a wireless communication apparatus that uses a first set of complex-valued codes (e.g., a DFT matrix) to encode data symbols and a second set (e.g., an IDFT matrix, which is the complex conjugate of the first) to recover them. The encoded symbols are applied to a selection of subcarriers to create a spread-OFDM signal. (’786 Patent, Abstract).
  • Asserted Claims: The complaint asserts independent claim 10 and dependent claims 11, 15, 16, 17, and 18. (Compl. ¶¶255, 271, 277, 283, 289, 295).
  • Accused Features: The accused devices' implementation of the LTE SC-FDMA uplink scheme is alleged to infringe. This includes selecting subcarriers, encoding data using complex-valued codes via transform precoding (a DFT), and applying the encoded data to produce a spread-OFDM signal. (Compl. ¶¶259, 262, 264, 267).

Multi-Patent Capsule: U.S. Patent No. 11,223,508 - "Wireless communications using flexible channel bandwidth"

  • Patent Identification: U.S. Patent No. 11,223,508, "Wireless communications using flexible channel bandwidth," issued January 11, 2022. (Compl. ¶51).
  • Technology Synopsis: This patent relates to providing flexibility in wireless communications by provisioning different selectable subcarrier spacings for a series of OFDM subcarriers. This technique, central to 5G "numerology," allows the signal structure to be adapted for different deployment scenarios by changing the symbol periods. The patent claims an apparatus that performs DFT coding and inverse-DFT to generate a single-carrier signal transmitted using one of these selectable subcarrier spacings. (’508 Patent, Abstract).
  • Asserted Claims: The complaint asserts independent claim 17 and dependent claims 18, 19, 20, 21, and 22. (Compl. ¶¶301, 312, 318, 324, 330, 337).
  • Accused Features: The complaint alleges infringement by the accused 5G devices' compliance with the 5G wireless standard. This includes the use of transceiver-control circuitry to provision different selectable subcarrier spacings (e.g., 15, 30, 60 kHz) and to perform DFT coding and inverse-DFT for uplink signal transmission. (Compl. ¶¶303, 305, 306, 308).

III. The Accused Instrumentality

  • Product Identification: The complaint identifies two categories of accused products: "Accused Asus LTE Devices" and "Accused Asus 5G Devices." (Compl. ¶¶53-54).
    • Accused Asus LTE Devices include, but are not limited to, the ZenFone 5, 6, 7, and 8 series mobile phones, and the ZenPad 7, 8, and 9 series tablets. (Compl. ¶53).
    • Accused Asus 5G Devices include, but are not limited to, the ZenFone 7 and 8 series mobile phones. (Compl. ¶54).
  • Functionality and Market Context: The accused products are alleged to be mobile devices that provide network connectivity by adhering to 4G LTE and/or 5G wireless standards. (Compl. ¶¶53-54). The complaint alleges these devices contain transmitters that perform Single-Carrier Frequency-Division Multiple Access (SC-FDMA) for uplink communications, a process that involves "Transform Precoding" and "SC-FDMA baseband signal generation" as defined by the 3GPP technical specifications. (Compl. ¶¶69-72). For example, the Asus ZenFone 8 is alleged to use the Qualcomm Snapdragon 888 5G Mobile Platform system-on-a-chip for this functionality. (Compl. ¶68). The complaint includes a screenshot from an email survey sent to a U.S. consumer after purchasing a Zenfone 9, identifying the sender as "ASUS" in Taiwan, as evidence of Defendant's direct sales and marketing activities in the U.S. (Compl. ¶24, p. 13).

IV. Analysis of Infringement Allegations

’842 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
An OFDM transmitter, comprising: The Accused Asus LTE Devices include a transmitter used for LTE network connectivity. ¶68 col. 6:2-3
an OFDM spreader configured to spread a plurality of data symbols with Fourier coefficients to generate a discrete Fourier Transform (DFT)-spread data signal; The transmitter includes an OFDM spreader that performs Transform Precoding according to the 3GPP LTE specification, which uses a discrete Fourier transform to spread data symbols. The complaint provides a screenshot of the relevant 3GPP formula. ¶70 col. 6:50-55
a mapper configured to map the DFT-spread data signal to a plurality of OFDM subcarriers; The transmitter includes a mapper that maps the spread data signals to physical resource elements (subcarriers) consistent with the LTE specification. ¶71 col. 6:56-58
an OFDM modulator configured to modulate the DFT-spread data signal onto the plurality of OFDM subcarriers to produce an OFDM transmission signal comprising a superposition of the OFDM subcarriers, wherein the OFDM spreader is configured to provide the superposition with a reduced peak-to-average power ratio. The transmitter includes an OFDM modulator that performs SC-FDMA baseband signal generation, modulating the symbols onto subcarriers. This process results in a superposition of subcarriers that has a lower peak-to-average power ratio (PAPR) than standard OFDM signals. ¶72, ¶70 col. 6:59-65
  • Identified Points of Contention:
    • Scope Questions: A potential area of dispute may be whether the term "OFDM spreader" as defined in the patent is synonymous with the "Transform Precoding" block in the 3GPP LTE standard. A defendant could argue the claimed "spreader" is a distinct component, whereas the accused functionality is part of an integrated, standardized signal processing chain.
    • Technical Questions: Claim 1 requires that the "OFDM spreader is configured to provide" the reduced PAPR. The complaint alleges that this reduction is a "feature resulting from transform precoding." (Compl. ¶70). This raises the question of whether the PAPR reduction is an intentional, configured purpose of the accused component, as the claim language may require, or an inherent, incidental property of the overall SC-FDMA transmission scheme defined by the standard.

’227 Patent Infringement Allegations

Claim Element (from Independent Claim 22) Alleged Infringing Functionality Complaint Citation Patent Citation
An apparatus comprising: a processor; and a non-transitory memory...with instructions...to: The Accused Asus LTE Devices have processors (e.g., Qualcomm Snapdragon 888) and non-transitory memory (e.g., LPRDDR) that store instructions for LTE physical channel processing. ¶134 col. 28:51-56
perform an invertible transform on a set of data symbols to generate a plurality N of spread data symbols... The memory includes instructions to perform transform precoding on data symbols using a discrete Fourier transform (DFT), which is an invertible transform, as defined by the LTE Specification. The complaint includes a screenshot of the 3GPP formula for this process. ¶135, ¶136 col. 28:57-61
map the N spread data symbols to at least N subcarriers of a plurality M of Orthogonal Frequency Division Multiplexing (OFDM) subcarriers... The memory includes instructions to map the N spread data signals onto N subcarriers consistent with the LTE Specification. ¶137 col. 28:62-65
perform an M-point inverse discrete Fourier transform (IDFT)...to generate a time-domain sequence...wherein the invertible transform is configured to provide the superposition with a reduced peak-to-average power ratio. The memory includes instructions for SC-FDMA baseband signal generation using an M-point IDFT. The transform precoding process is alleged to result in a superposition of subcarriers with a lower PAPR compared to standard downlink OFDM signals. ¶139, ¶136 col. 28:66-68; col. 29:1-4
  • Identified Points of Contention:
    • Scope Questions: Practitioners may question whether a general-purpose processor and memory executing instructions that comply with a public standard meet the claim limitation of an "apparatus" with memory including a "set of instructions stored therein" for performing the claimed steps, particularly when the functionality is dictated by the standard rather than proprietary software.
    • Technical Questions: Similar to the '842 Patent, the dispute may focus on the phrase "wherein the invertible transform is configured to provide the superposition with a reduced peak-to-average power ratio." The central technical question is whether the PAPR reduction is a configured purpose of the "invertible transform" block itself, or an emergent property of the entire standardized system architecture that the accused devices implement.

V. Key Claim Terms for Construction

  • The Term: "OFDM spreader configured to provide the superposition with a reduced peak-to-average power ratio" (from '842 Patent, Claim 1).

  • Context and Importance: This term is critical because it links a structural element ("OFDM spreader") with a functional outcome ("provide... reduced peak-to-average power ratio"). The infringement analysis will depend on whether the accused "Transform Precoding" block from the LTE standard performs this specific, configured function. Practitioners may focus on this term because the heart of the dispute is whether implementing a standard that results in a benefit is the same as infringing a claim that requires a component to be configured to provide that benefit.

  • Intrinsic Evidence for Interpretation:

    • Evidence for a Broader Interpretation: The patent's abstract states that the "Fourier coefficients reduce the transmission signal's peak to average power," which could support an argument that the use of a DFT (which is defined by Fourier coefficients) inherently provides for this function. (’842 Patent, Abstract).
    • Evidence for a Narrower Interpretation: The claim language specifies the "OFDM spreader" as the component configured to provide the result. A defendant may argue that in the accused devices, the transform precoding block is a generic DFT processor, and the PAPR reduction is a system-level outcome of the entire SC-FDMA scheme (precoding, mapping, and modulation), not a configured function of the spreader alone.

  • The Term: "invertible transform is configured to provide the superposition with a reduced peak-to-average power ratio" (from '227 Patent, Claim 22).

  • Context and Importance: This limitation is the functional core of claim 22. Its interpretation will determine whether the accused devices, by executing standard-compliant code on a general-purpose processor, infringe. The case may turn on the meaning of "configured to," specifically whether it requires a specific design intent for the transform block itself, beyond its mathematical function as a DFT.

  • Intrinsic Evidence for Interpretation:

    • Evidence for a Broader Interpretation: The '227 Patent specification suggests that employing the described pre-coding technique inherently yields the PAPR benefit, stating that the invention relates to "spread Orthogonal Frequency Division Multiplexing" that can have "low peak to average power ratio." (’227 Patent, col. 1:49-50, col. 7:5-10).
    • Evidence for a Narrower Interpretation: The prosecution history (not provided, but a likely source of argument) may contain statements distinguishing the invention from a generic DFT. A defendant could argue that the term "configured to" implies that the transform block was specifically designed or modified for the purpose of PAPR reduction, rather than simply being a standard mathematical function that, when used in a particular system, happens to contribute to that result.

VI. Other Allegations

  • Indirect Infringement: The complaint includes a general allegation that Defendant has continued to "induce the infringement of, the Patents-in-Suit." (Compl. ¶63). However, the complaint does not plead specific facts to support a claim for indirect infringement, such as alleging that Defendant's user manuals instruct customers to use the accused devices in an infringing manner. The infringement counts focus on allegations of direct infringement by Asus.
  • Willful Infringement: The complaint alleges willful infringement based on pre-suit and post-suit knowledge. (Compl. ¶¶346-347). It is alleged that Defendant had knowledge of the ’842, ’227, and ’568 Patents since at least November 19, 2020, due to a notice letter with claim charts, and had knowledge of the ’786 and ’508 Patents as of the filing of the complaint. (Compl. ¶¶55, 62). The basis for willfulness is the allegation that Defendant continued its infringing conduct despite this knowledge.

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

  • A core issue will be one of claim scope and standards implementation: can claim terms requiring a component to be "configured to provide" a specific result (i.e., reduced PAPR) be met by an accused device that merely implements a public telecommunications standard (4G LTE/5G) on general-purpose hardware, where that standard inherently produces the same result?
  • A central evidentiary question will be one of technical mapping: does the operational sequence defined by the 3GPP standards for SC-FDMA uplink—specifically the functions of "Transform Precoding," "Mapping to Physical Resources," and "SC-FDMA baseband signal generation"—satisfy each and every limitation of the asserted apparatus claims as written in the patents? The dispute may focus on whether the discrete claim elements have one-to-one correspondents in the accused standardized process.