Swirlate IP LLC v. Jabil Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Swirlate IP LLC (Texas)
  • Defendant: Jabil Inc. (Illinois)
  • Plaintiff’s Counsel: Direction IP Law
• Case Identification: 1:22-cv-04557, N.D. Ill., 08/26/2022
• Venue Allegations: Plaintiff alleges venue is proper because Defendant maintains regular and established places of business within the Northern District of Illinois and has committed acts of infringement in the district.
• Core Dispute: Plaintiff alleges that Defendant’s Jabil YT-Touch point-of-sale terminal infringes two patents related to methods for improving data reliability in wireless communication systems using constellation rearrangement for retransmissions.
• Technical Context: The technology addresses error-correction in wireless protocols like 4G LTE, specifically using a technique called Hybrid Automatic Repeat Request (HARQ) where different data modulation schemes are used for initial transmissions and subsequent retransmissions to improve the probability of a successful decoding.
• Key Procedural History: The complaint notes that U.S. Patent No. 7,567,622 is a continuation of the application that led to U.S. Patent No. 7,154,961. The complaint also references statements made during the prosecution of the '622 Patent, where the applicant distinguished the invention by highlighting that retransmission is only used when an initial transmission fails, thereby reducing overall data traffic compared to prior art that always used multiple parallel transmission paths.

Case Timeline

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

U.S. Patent No. 7,154,961 - "Constellation Rearrangement for ARQ Transmit Diversity Schemes"

• The Invention Explained:
  • Problem Addressed: In wireless systems using higher-order modulation (where more than two bits are mapped to a single transmission symbol), the different bit positions within the symbol can have unequal error reliabilities. This variation can degrade the performance of error-correction decoders, even when signals from multiple diversity branches are combined. (’961 Patent, col. 2:1-11; Compl. ¶14).
  • The Patented Solution: The invention proposes improving receiver performance by applying different signal constellation mappings (i.e., different bit-to-symbol mapping rules) to different transmit diversity branches and to Automatic Repeat reQuest (ARQ) retransmissions. This process averages the reliability levels across all bits of a symbol, leading to a more robust signal for the receiver to decode. (’961 Patent, col. 2:19-29; Compl. ¶15).
  • Technical Importance: This technique aims to enhance the reliability and efficiency of data transmission in challenging wireless environments by improving the effectiveness of error correction schemes. (’961 Patent, col. 2:15-18).
• Key Claims at a Glance:
  • The complaint asserts at least independent claim 1. (Compl. ¶16).
  • The essential elements of independent claim 1 are:
    • An ARQ re-transmission method in a wireless system.
    • Modulating data packets at a transmitter using a first modulation scheme to obtain first data symbols.
    • Transmitting the first data symbols over a first diversity branch.
    • Modulating the same data packets using a second modulation scheme to obtain second data symbols.
    • Transmitting the second data symbols over a second diversity branch.
    • Demodulating the received symbols at the receiver using the first and second modulation schemes.
    • Diversity combining the demodulated data.
    • The method requires that the modulation schemes are 16 QAM and a number of log2(M) modulation schemes are used.
  • The complaint does not explicitly reserve the right to assert dependent claims.

U.S. Patent No. 7,567,622 - "Constellation Rearrangement for ARQ Transmit Diversity Schemes"

• The Invention Explained:
  • Problem Addressed: The '622 Patent shares its specification with the '961 Patent and addresses the same problem of unequal bit reliabilities in higher-order modulation schemes. (Compl. ¶28; ’622 Patent, col. 2:1-11).
  • The Patented Solution: The solution is also centered on using different signal constellation mappings for initial transmissions and retransmissions. The prosecution history cited in the complaint emphasizes that this approach averages the communication reliabilities for each bit to improve the likelihood of correct reception. (Compl. ¶29). The '622 Patent claims specify that the different mappings are "pre-stored in a memory table." (’622 Patent, col. 8:47-49).
  • Technical Importance: The complaint highlights an advantage noted during prosecution: the claimed method reduces overall data traffic by employing retransmission and diversity combining only when an initial transmission is not successfully received. (Compl. ¶30).
• Key Claims at a Glance:
  • The complaint asserts at least independent claim 1. (Compl. ¶31).
  • The essential elements of independent claim 1 are:
    • An ARQ re-transmission method using a higher order modulation scheme where more than two data bits are mapped to one symbol.
    • Modulating data packets using a "first mapping" to obtain first data symbols and transmitting them.
    • Receiving a repeat request at the transmitter if the first transmission was not successfully decoded.
    • In response, modulating the data packets using a "second mapping" to obtain second data symbols and transmitting them.
    • Demodulating and diversity combining at the receiver.
    • A key limitation is that "the first and second mapping of said higher order modulation schemes are pre-stored in a memory table."
  • The complaint does not explicitly reserve the right to assert dependent claims.

III. The Accused Instrumentality

Product Identification

• The Jabil YT-Touch, described as a mobile point-of-sale (mPOS) terminal. (Compl. ¶16, p. 6).

Functionality and Market Context

• The YT-Touch is a compact, autonomous POS terminal that connects to payment networks using 4G LTE cellular technology. (Compl. p. 6). The complaint alleges that when operating on an LTE network, the YT-Touch practices a Hybrid ARQ (HARQ) re-transmission method to ensure reliable data communication between the device (transmitter) and an LTE base station (receiver). (Compl. ¶17). This allegedly involves using higher-order modulation schemes such as QPSK, 16QAM, and 64QAM, and employing different schemes for initial transmissions and subsequent retransmissions upon receiving a repeat request (NAK). (Compl. ¶18, ¶20). The complaint includes a datasheet describing the product as the "Smallest POS Ever." (Compl. p. 6).

IV. Analysis of Infringement Allegations

’961 Patent Infringement Allegations

• Identified Points of Contention:
  • Scope Questions: A central question will be whether the accused product's use of "Adaptive Re-transmission" in LTE, which involves changing the Modulation and Coding Scheme (MCS), constitutes using a "second modulation scheme" that is distinct from the first, as the patent may require. A defendant could argue that varying the MCS is part of a single, flexible scheme, not the use of two distinct schemes as depicted in the patent's embodiments (e.g., FIG. 1 vs. FIG. 2).
  • Technical Questions: The complaint's theory relies on equating the patent's "modulation scheme" with LTE's "Modulation and Coding Scheme." The court will need to determine if the technical operation of changing an MCS in a standard LTE HARQ process is the same as the "constellation rearrangement" described in the patent, which focuses on averaging bit reliabilities by altering bit-to-symbol mappings.

’622 Patent Infringement Allegations

• Identified Points of Contention:
  • Scope Questions: The interpretation of "pre-stored in a memory table" will be critical. The complaint's evidence shows a MAC scheduler decides the modulation scheme, which raises the question of whether this is equivalent to selecting from a "pre-stored...table" of specific bit-to-symbol mappings, or if the scheduler implements a more dynamic logic.
  • Technical Questions: What evidence demonstrates that the accused device contains the specific "memory table" structure recited in the claim? The complaint's infringement theory appears to infer the existence of this structure from the general functionality of an LTE MAC scheduler, a point a defendant may contest as lacking direct proof.

V. Key Claim Terms for Construction

• The Term: "modulation scheme" (asserted in '961 and '622 Patents)

• Context and Importance: The core of the infringement allegation is that the accused product uses a first modulation scheme for an initial transmission and a distinct second modulation scheme for retransmission. The case may turn on whether changing the "Modulation and Coding Scheme" (MCS) in standard LTE adaptive HARQ constitutes a change in "modulation scheme" as understood in the context of the patents.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The specification focuses on applying "different signal constellation mappings" to average bit reliabilities ('961 Patent, col. 2:20-23). A plaintiff may argue that any change that results in a different mapping of bits to symbols, such as a change in MCS, falls within the scope of a different "scheme."
  • Evidence for a Narrower Interpretation: The patent’s examples illustrate distinct, static constellation maps (e.g., FIG. 1 vs. FIG. 2, which rearrange the bit order for the same 16-QAM constellation). A defendant may argue this requires a specific type of constellation rearrangement, not merely selecting a different pre-standardized MCS level.

• The Term: "pre-stored in a memory table" (asserted in '622 Patent)

• Context and Importance: This limitation appears in claim 1 of the '622 patent but not the '961 patent, suggesting it is a key distinguishing feature. Infringement of the '622 patent hinges on finding this specific implementation detail in the accused product.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: A plaintiff may argue that for a "MAC Scheduler" to decide on a scheme, the available schemes must be defined and stored in some form of memory accessible to the scheduler, which is functionally equivalent to a "memory table." The patent itself shows a "TABLE 15" storing constellation patterns that are selected for use. ('622 Patent, FIG. 4, col. 8:15-20).
  • Evidence for a Narrower Interpretation: A defendant may argue the term requires a literal data structure corresponding to a "table" that is "pre-stored" (i.e., loaded before operation) with the specific bit-to-symbol mappings. The complaint’s evidence from LTE standards shows a scheduler deciding a scheme but does not explicitly depict a "pre-stored...table" of mappings.

VI. Other Allegations

• Indirect Infringement: The complaint does not contain specific counts or factual allegations for indirect or contributory infringement, focusing instead on Defendant's direct performance of the claimed methods. (Compl. ¶16, ¶31).
• Willful Infringement: The complaint does not allege willful infringement or pre-suit knowledge of the patents. The prayer for relief does not request enhanced damages.

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

This case will likely depend on the resolution of several key technical and legal questions concerning the relationship between the asserted patent claims and the operation of standardized LTE technology.

• A core issue will be one of definitional scope: Does the term "modulation scheme" as used in the patents, which describe specific constellation rearrangements, read on the practice of changing the "Modulation and Coding Scheme" (MCS) as part of the standardized adaptive HARQ protocol in LTE?
• A second central issue will be one of evidentiary sufficiency: For the '622 patent, can the limitation requiring mappings to be "pre-stored in a memory table" be met by evidence showing the standard operation of an LTE "MAC Scheduler," or will Plaintiff need to provide more direct evidence of such a table structure within the accused device?
• A key technical question will be one of functional correspondence: Does the accused product's alleged use of adaptive retransmission in LTE perform the same function in the same way as the invention described in the patents—specifically, is its primary purpose and mechanism to "average out the reliabilities for all bits," or is it simply a standard mechanism for adapting data rate to channel conditions, with any effect on bit reliability being incidental?