PTAB

IPR2018-01724

Cisco Systems Inc v. TracBeam LLC

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Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Gateway and Hybrid Solutions for Wireless Location
  • Brief Description: The ’484 patent relates to wireless communication systems for locating mobile stations (e.g., people or objects). The technology uses measurements from wireless signals communicated between mobile stations and network base stations and utilizes a plurality of wireless location estimators based on different location technologies to determine a final location.

3. Grounds for Unpatentability

Ground 1: Obviousness over Sheffer II and Cisneros - Claim 49 is obvious over Sheffer II in view of Cisneros.

  • Prior Art Relied Upon: Sheffer II (Patent 5,218,367) and Cisneros (Patent 5,774,829).

  • Core Argument for this Ground:

    • Prior Art Mapping: Petitioner argued that Sheffer II discloses the core method of claim 49. Sheffer II teaches a vehicle tracking system that uses two distinct and independent techniques to determine a vehicle's location, thereby functioning as the claimed "first and second mobile station location estimators." The first technique is a cell triangulation calculation based on signal strength from three cell sites, which generates a first geographical approximation ("Area A"). The second technique uses sector information from cell sites to refine the vehicle's position, generating a second geographical approximation ("Area A1"). Petitioner contended that Sheffer II's system receives these two distinct location approximations from its two estimators.

    To address the limitation of combining these approximations to create a resulting estimate dependent on both (substep B1), Petitioner argued that Cisneros renders this step obvious. Cisneros describes a navigation system that also uses multiple independent location techniques (e.g., uncoordinated radio broadcasts and GPS). Crucially, Cisneros explicitly teaches combining the resulting position solutions to improve accuracy, such as by taking an average or, more specifically, by weighting "each position solution in accordance with its estimated quality" to yield a "composite estimate." Petitioner asserted that applying Cisneros's method of weighting and combining two location estimates to the two estimates ("Area A" and "Area A1") generated by Sheffer II directly teaches the combination required by claim 49.

    • Motivation to Combine (for §103 grounds): Petitioner argued a person of ordinary skill in the art (POSITA) would combine the teachings of Sheffer II and Cisneros to improve the accuracy of the location system. A POSITA would recognize that Sheffer II's two location techniques (cell triangulation vs. sector-based) might have varying levels of accuracy depending on the environment (e.g., urban vs. rural). Cisneros provides a known and logical solution for improving overall accuracy by weighting and combining these multiple estimates, favoring the technique likely to be more accurate in a given situation.
    • Expectation of Success (for §103 grounds): A POSITA would have had a reasonable expectation of success in this combination because both Sheffer II and Cisneros operate in the same field of mobile device location using wireless signals and describe similar types of cellular communication technology, making their integration predictable.

4. Key Claim Construction Positions

  • "mobile station location estimator": Petitioner argued this term is a means-plus-function term under 35 U.S.C. §112, ¶ 6. The proposed function is "estimating [a] mobile station location." The corresponding structure identified in the ’484 patent specification is a "location hypothesizing model (FOM) implemented on or by a location center or mobile base station." This construction was central to mapping the computational techniques of Sheffer II (cell triangulation and sector triangulation) to the claimed "estimators."
  • "at least one of the substeps (B1) through (B2)": Petitioner asserted that the ordinary and customary meaning of this phrase is "at least substep (B1) or at least substep (B2)." This interpretation is critical because Petitioner's argument focused on demonstrating that the combination of Sheffer II and Cisneros teaches the "combining" method of substep (B1), and therefore it was not necessary to show that the prior art also taught the "selecting" method of substep (B2).

5. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claim 49 of the ’484 patent as unpatentable.