DCT

5:20-cv-01030

ParkerVision Inc v. TCL Technology Group Corp

Log In

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 5:20-cv-01030, C.D. Cal., 05/14/2020
  • Venue Allegations: Venue is alleged to be proper in the Central District of California because Defendant TTE Technology, Inc. is registered to do business in the state, maintains a regular and established place of business in the district, and has committed alleged acts of infringement within the district.
  • Core Dispute: Plaintiff alleges that Defendant’s smart televisions, which incorporate specific Wi-Fi chips, infringe ten patents related to methods and systems for down-converting radio frequency (RF) signals.
  • Technical Context: The technology at issue involves foundational techniques for processing RF signals in wireless receivers, a critical function for enabling wireless connectivity in a vast range of consumer electronics, including smart televisions.
  • Key Procedural History: The complaint describes Plaintiff's history of developing RF technologies since the 1990s but does not reference prior litigation or post-grant proceedings involving the patents-in-suit.

Case Timeline

Date Event
1998-07-08 Earliest Priority Date for ’902 and ’673 Patents
1998-10-21 Earliest Priority Date for ’706, ’518, ’444, ’835, ’725, ’513, ’528, and ’736 Patents
2000-04-11 U.S. Patent No. 6,049,706 Issues
2001-07-24 U.S. Patent No. 6,266,518 Issues
2003-06-17 U.S. Patent No. 6,580,902 Issues
2006-09-19 U.S. Patent No. 7,110,444 Issues
2007-11-06 U.S. Patent No. 7,292,835 Issues
2013-11-19 U.S. Patent No. 8,588,725 Issues
2014-01-01 TCL began selling accused products in the U.S. (earliest date alleged)
2014-02-25 U.S. Patent No. 8,660,513 Issues
2015-08-25 U.S. Patent No. 9,118,528 Issues
2016-01-26 U.S. Patent No. 9,246,736 Issues
2016-09-13 U.S. Patent No. 9,444,673 Issues
2020-05-14 Complaint Filed

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

  • Patent Identification: U.S. Patent No. 6,049,706, "Integrated Frequency Translation and Selectivity," issued April 11, 2000.

  • The Invention Explained:

    • Problem Addressed: The patent addresses performance degradation in conventional radio receivers, which traditionally use separate, wide-band filters before frequency down-conversion. This approach allows unwanted signals to reach nonlinear components like amplifiers and mixers, generating spurious signals that can interfere with the desired signal being received (’706 Patent, col. 1:24-30, col. 2:5-32).
    • The Patented Solution: The invention proposes a unified module that performs both frequency filtering and down-conversion in an integrated manner. The system generates an output signal by combining delayed samples of the high-frequency input signal with delayed instances of its own output signal, a recursive process that achieves narrowband filtering and frequency translation simultaneously (’706 Patent, Abstract; col. 3:28-49). This architecture is described as a "unified downconverting and filtering (UDF) module" (’706 Patent, Fig. 11).
    • Technical Importance: This integrated approach to filtering and down-conversion enabled the creation of RF receivers that were smaller, more power-efficient, and more easily implemented on a single integrated circuit (Compl. ¶16).

  • Key Claims at a Glance:

    • The complaint asserts independent claim 1 (Compl. ¶57).
    • The essential elements of Claim 1 are:
      • An apparatus for filtering and down-converting an input signal.
      • A frequency translator comprising a "down-convert and delay module" to under-sample an input signal to produce and delay an input sample.
      • A filter comprising a portion of the down-convert and delay module, at least one delay module for the output signal, and an adder.
      • The adder combines the delayed input sample with at least one delayed instance of the output signal to generate a new instance of the output signal.
    • The complaint reserves the right to assert additional claims (Compl. ¶58).

  • Patent Identification: U.S. Patent No. 6,266,518, "Method and System for Down-Converting Electromagnetic Signals by Sampling and Integrating Over Apertures," issued July 24, 2001.

  • The Invention Explained:

    • Problem Addressed: The patent seeks to improve upon conventional down-converters, which are described as often being complex, expensive, and difficult to implement on integrated circuits. These conventional systems can also be susceptible to performance degradation from noise and interference (’518 Patent, col. 1:16-43).
    • The Patented Solution: The invention discloses a method of down-converting a signal by sampling it with a train of pulses at an "aliasing rate" that is substantially lower than the signal's frequency. A switch, controlled by these pulses, transfers energy from the input signal to an integrator (e.g., a capacitor) during brief time windows called "apertures." The accumulated energy in the integrator forms the down-converted signal (’518 Patent, Abstract; col. 12:1-20). This process is referred to as a "universal frequency down-converter" (UFD).
    • Technical Importance: This direct-conversion technology, which relies on energy transfer via sampling, provided a basis for RF chips that were lower power and more highly integrated, facilitating their use in mass-market consumer devices (Compl. ¶16).

  • Key Claims at a Glance:

    • The complaint asserts independent claim 67 (Compl. ¶63).
    • The essential elements of Claim 67 are:
      • An apparatus for down-converting a carrier signal to a lower frequency signal.
      • A universal frequency down-converter (UFD) comprising a switch, an integrator coupled to the switch, and a pulse generator coupled to the switch.
      • The pulse generator outputs pulses to the switch at an aliasing rate determined according to a specified formula involving the carrier and lower frequency signals.
      • A reactive structure coupled to the UFD.
    • The complaint reserves the right to assert additional claims (Compl. ¶64).

  • Multi-Patent Capsule: U.S. Patent No. 6,580,902

    • Patent Identification: U.S. Patent No. 6,580,902, "Frequency Translation Using Optimized Switch Structures," issued June 17, 2003.
    • Technology Synopsis: This patent describes a circuit for down-converting an electromagnetic signal using an "energy transfer module." The module contains a switch (e.g., transistors) and an energy storage element (e.g., capacitors) to sample and store energy from the input signal, from which a down-converted signal is generated. The patent focuses on specific transistor configurations, such as those with common ports for input, output, and control signals.
    • Asserted Claims: Independent claim 1 (Compl. ¶71).
    • Accused Features: The accused TCL Chips are alleged to contain an energy transfer module with a switch module (one or more transistors) and an energy storage module (one or more capacitors) that sample an electromagnetic signal at a specific rate to generate a down-converted signal (Compl. ¶73).

  • Multi-Patent Capsule: U.S. Patent No. 7,110,444

    • Patent Identification: U.S. Patent No. 7,110,444, "Wireless Local Area Network (WLAN) Using Universal Frequency Translation Technology Including Multi-Phase Embodiments and Circuit Implementations," issued September 19, 2006.
    • Technology Synopsis: This patent discloses a wireless modem apparatus with a receiver that uses two separate frequency down-conversion modules. Each module down-converts the input signal according to a distinct control signal. A subtractor module then subtracts the output of the second module from the first to generate the final down-converted signal.
    • Asserted Claims: Independent claim 2 (Compl. ¶79).
    • Accused Features: The accused TCL Chips are alleged to function as wireless modems containing a receiver with first and second frequency down-conversion modules and a subtractor module (e.g., a differential amplifier) that operate in the claimed manner (Compl. ¶81).

  • Multi-Patent Capsule: U.S. Patent No. 7,292,835

    • Patent Identification: U.S. Patent No. 7,292,835, "Wireless and Wired Cable Modem Applications of Universal Frequency Translation Technology," issued November 6, 2007.
    • Technology Synopsis: This patent describes a cable modem for down-converting signals with complex modulations. The system uses an oscillator and a phase shifter to generate in-phase and quadrature-phase oscillating signals. These signals control first and second down-conversion modules, respectively, which sample the incoming electromagnetic signal to create two sampled signals for further processing.
    • Asserted Claims: Independent claims 1 and 17 (Compl. ¶85).
    • Accused Features: The accused TCL Chips are alleged to function as wireless cable modems that include an oscillator (LO), a phase shifter, and first and second frequency down-conversion modules that sample the input signal as a function of the in-phase and quadrature-phase signals (Compl. ¶89).

  • Multi-Patent Capsule: U.S. Patent No. 8,588,725

    • Patent Identification: U.S. Patent No. 8,588,725, "Apparatus, System, and Method For Down Converting and Up-Converting Electromagnetic Signals," issued November 19, 2013.
    • Technology Synopsis: This patent discloses an apparatus for down-converting a signal using an "aliasing module." The module includes a switching device and a storage module. A control signal governs a charging and discharging cycle where energy is transferred from the RF signal to the storage module during a charging phase and then discharged during a discharging phase to generate the down-converted signal.
    • Asserted Claims: Independent claim 1 (Compl. ¶94).
    • Accused Features: The accused TCL Chips are alleged to include an aliasing module with a switching device (transistor) and a storage module (capacitors) that performs the claimed charging and discharging cycle under the control of an LO signal (Compl. ¶96).

  • Multi-Patent Capsule: U.S. Patent No. 8,660,513

    • Patent Identification: U.S. Patent No. 8,660,513, "Method and System for Down-Converting an Electromagnetic Signal, and Transforms for Same, and Aperture Relationships," issued February 25, 2014.
    • Technology Synopsis: This patent describes a system for down-converting a modulated carrier signal into differential in-phase and quadrature-phase components. It uses a set of four switches, each controlled by a signal with a specific sampling aperture, and associated energy storage elements. Differential amplifiers combine the outputs to generate the final differential signals.
    • Asserted Claims: Independent claim 19 (Compl. ¶100).
    • Accused Features: The accused TCL Chips are alleged to include first and second switches and energy storage elements that down-convert a signal according to a control signal to produce in-phase and inverted in-phase signal portions, which are then combined by a differential amplifier circuit (Compl. ¶¶102-104).

  • Multi-Patent Capsule: U.S. Patent No. 9,118,528

    • Patent Identification: U.S. Patent No. 9,118,528, "Method and System for Down-Converting an Electromagnetic Signal, and Transforms for Same, and Aperture Relationships," issued August 25, 2015.
    • Technology Synopsis: This patent discloses a system for down-converting a modulated carrier signal to a baseband signal. It uses first and second switches controlled by signals with specified sampling apertures. During the "on" portion of the aperture, a portion of energy "distinguishable from noise" is transferred to respective energy storage elements. The energy is then integrated over time to derive the baseband signal.
    • Asserted Claims: Independent claim 1 (Compl. ¶110).
    • Accused Features: The accused TCL Chips are alleged to include a system with first and second switches and energy storage elements that transfer and store energy from a modulated carrier signal, which is then integrated to derive down-converted baseband signals (Compl. ¶¶112-117).

  • Multi-Patent Capsule: U.S. Patent No. 9,246,736

    • Patent Identification: U.S. Patent No. 9,246,736, "Method and System for Down-Converting an Electromagnetic Signal," issued January 26, 2016.
    • Technology Synopsis: This patent is directed to a down-conversion system where energy storage elements undergo charging and discharging cycles. A key feature is that the energy discharged during a given cycle is not completely discharged, with the remaining undischarged energy becoming an initial condition for the next charging cycle. The final down-converted signal is derived from energy accumulated during both charging and discharging cycles.
    • Asserted Claims: Independent claim 1 (Compl. ¶120).
    • Accused Features: The accused TCL Chips are alleged to contain a system where energy storage elements are not completely discharged during each cycle, with the remaining energy serving as an initial condition for the next cycle, and where the down-converted signal is derived from energy accumulated during both cycles (Compl. ¶¶122-128).

  • Multi-Patent Capsule: U.S. Patent No. 9,444,673

    • Patent Identification: U.S. Patent No. 9,444,673, "Methods and Systems for Down-Converting a Signal Using a Complementary Transistor Structure," issued September 13, 2016.
    • Technology Synopsis: This patent describes an apparatus for down-converting a modulated carrier signal to a demodulated baseband signal. The apparatus includes a down-conversion module with a switch, a capacitor, and a pulse generator. The generator outputs pulses that cause the switch to close and sample the signal, transferring energy to the capacitor. Some of this accumulated energy is then discharged into a load circuit when the switch is open to generate the baseband signal.
    • Asserted Claims: Independent claim 1 (Compl. ¶132).
    • Accused Features: The accused TCL Chips are alleged to include a frequency down-conversion module with a switch (transistor), a capacitor, and a pulse generator (LO) that accumulates and discharges energy to generate a demodulated baseband signal (Compl. ¶¶135-137).

III. The Accused Instrumentality

  • Product Identification: The accused products are TCL-branded smart televisions, which include wireless modules (e.g., WCOHR2601) containing Wi-Fi chips, such as the Realtek RT8812BU. The complaint collectively refers to these chips as the "TCL Chips." (Compl. ¶¶23, 25).
  • Functionality and Market Context: The accused TCL Chips are alleged to provide the Wi-Fi connectivity for TCL's smart televisions, enabling features like streaming content (Compl. ¶¶23, 87). The complaint alleges that in 2019, TCL was the second-largest brand of smart televisions in the United States (Compl. ¶22). The complaint provides a photograph of the accused Realtek RT8812BU Wi-Fi chip, which is alleged to perform the infringing down-conversion (Compl. p. 6).

IV. Analysis of Infringement Allegations

  • U.S. Patent No. 6,049,706 Infringement Allegations
Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
a frequency translator, comprising a down-convert and delay module to under-sample an input signal... to produce an input sample... and to delay said input sample Each TCL Chip has a down-convert and delay module that under-samples a high frequency RF signal to produce and delay an input sample of a down-converted image. ¶59 col. 15:10-25
a filter, comprising... at least one delay module to delay instances of an output signal, and an adder... to combine at least said delayed input sample with at least one of said delayed instances of said output signal to generate an instance of said output signal Each TCL Chip includes a filter with at least one delay module and an adder (e.g., an operational amplifier with feedback) to combine the delayed input sample with delayed instances of the output signal. ¶59 col. 15:55-67

  • Identified Points of Contention:

    • Scope Questions: A central question may be whether the accused chip's "operational amplifier with parallel resistor-capacitor feedback" (Compl. ¶59) falls within the scope of the term "adder" as used in the patent.
    • Technical Questions: The complaint alleges that the accused filter combines delayed input samples with delayed output instances. A key technical question for the court will be what evidence demonstrates that the accused chip's circuitry performs this specific recursive combination, as opposed to a more conventional filtering architecture.

  • U.S. Patent No. 6,266,518 Infringement Allegations

Claim Element (from Independent Claim 67) Alleged Infringing Functionality Complaint Citation Patent Citation
a universal frequency down-converter (UFD), including: a switch; The TCL Chip includes a UFD having a switch, which is alleged to be a transistor. ¶65 col. 67:40-45
an integrator coupled to said switch; The TCL Chip's UFD includes an integrator, alleged to be an operational amplifier with parallel resistor-capacitor feedback, coupled to the switch. ¶65 col. 67:46-49
a pulse generator coupled to said switch, wherein said pulse generator outputs pulses to said switch at an aliasing rate... The TCL Chip's UFD includes a pulse generator (e.g., a local oscillator) that outputs pulses to the switch at an aliasing rate. ¶65, ¶66 col. 27:20-30
a reactive structure coupled to said UFD... The TCL Chip's UFD is coupled to a reactive structure, which is alleged to be an active filter. ¶65 col. 67:53-56
  • Identified Points of Contention:
    • Scope Questions: The analysis may turn on whether the accused chip’s "active filter" (Compl. ¶65) meets the claim's requirement for a "reactive structure." The patent's definition and disclosed embodiments for this term will be critical.
    • Technical Questions: What evidence does the complaint provide that the accused chip's pulse generator operates at the specific "aliasing rate" defined by the mathematical formula in the claim? The complaint makes a conclusory assertion (Compl. ¶66) without providing supporting data or analysis of the chip's operation.

V. Key Claim Terms for Construction

  • The Term: "under-sample" ('706 Patent, Claim 1)

    • Context and Importance: The infringement theory for the ’706 Patent depends on the accused chip performing "under-sampling" to achieve down-conversion. The complaint alleges this means sampling below the Nyquist rate (Compl. ¶60). The construction of this term will be critical to determine whether the sampling technique used in the accused Wi-Fi chip meets this limitation.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The specification suggests that under-sampling is a process of sampling an input signal at a rate that is different from the frequency of the input signal, which results in frequency translation (’706 Patent, col. 28:10-15).
      • Evidence for a Narrower Interpretation: The claim language itself qualifies the under-sampling by requiring the control signal to have a frequency determined by a specific formula relating the input, output, and image frequencies (’706 Patent, col. 46:30-37). A defendant may argue this formula implicitly defines and narrows the scope of "under-sample" for this claim.

  • The Term: "integrator" ('518 Patent, Claim 67)

    • Context and Importance: The core of the ’518 Patent's inventive concept involves transferring energy to an "integrator" to generate the down-converted signal. The complaint alleges the accused chip's "operational amplifier with parallel resistor-capacitor feedback" is an integrator (Compl. ¶65). Whether this specific circuit qualifies as an "integrator" under the patent's terms is a likely point of dispute.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The patent describes the function of the integrator as accumulating energy transferred from the carrier signal during pulse apertures (’518 Patent, col. 12:13-16). This functional description could support a broader definition encompassing any circuit that performs this accumulation role.
      • Evidence for a Narrower Interpretation: The detailed description and figures show specific circuit implementations of the integrator (e.g., integrator 7004 in Fig. 70). This may support an argument that the term should be construed more narrowly to be consistent with the disclosed embodiments, which are distinct from a standard operational amplifier configuration.

VI. Other Allegations

  • Indirect Infringement: The complaint does not contain allegations of indirect infringement (i.e., induced or contributory infringement under 35 U.S.C. § 271(b) or (c)).
  • Willful Infringement: The complaint does not contain an explicit allegation of willful infringement or facts to support pre-suit knowledge of the patents, which could form the basis for enhanced damages. The prayer for relief requests attorney fees under 35 U.S.C. § 285, but this is distinct from a willfulness claim.

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

  • A central issue will be one of technical evidence: across ten related patents, the infringement allegations depend on the specific internal operations of the accused Realtek Wi-Fi chip. A key question for the court will be whether discovery produces evidence that the chip's circuits actually perform the precise energy transfer, aliasing, and recursive signal combination functions required by the various asserted claims.
  • The case may also turn on a question of claim scope: can claim terms from patents with priority dates in the late 1990s, such as "adder" and "integrator", be construed to cover the highly integrated and potentially multi-functional circuit blocks found in a modern Wi-Fi chip, or are there fundamental operational and structural differences?
  • Given the assertion of ten patents from a dense family with shared specifications, a significant procedural question will be one of case management and focus: how will the plaintiff and the court distinguish the unique contribution and infringement basis of each patent, and will the case narrow to a smaller set of representative claims to avoid redundancy?