PTAB

IPR2018-01723

Cisco Systems, Inc. v. TracBeam LLC

Log In

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. The system is designed to use measurements from wireless signals communicated between mobile devices and fixed network base stations and to utilize a plurality of location estimators based on different location technologies to determine a mobile station's position.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claim 25 over Sheffer

  • Prior Art Relied Upon: Sheffer (Patent 5,844,522).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Sheffer (filed in 1995) discloses every element of claim 25. Sheffer describes a wireless network-based system to locate any active phone by initiating requests to at least two independent "location evaluators." Petitioner contended these evaluators correspond to distinct software routines on a central dispatch center (CDC) workstation: one using an azimuth triangulation technique to determine a first location area ("Area A") and a second using a Received Signal Strength Information (RSSI) technique to determine a second location area ("Area B"). The final location is determined by comparing these independently derived areas and assessing a confidence level, which Petitioner asserted makes the final result "dependent on geographical information" from both. The resulting coordinates are then transmitted to a predetermined destination (a dispatched vehicle's automatic tuner).
    • Key Aspects: The core of the anticipation argument relied on interpreting Sheffer's distinct computational processes (azimuth vs. RSSI) as the claimed "at least two mobile station location evaluators" and its result-comparison logic as meeting the claim's "dependency" requirement.

Ground 2: Obviousness of Claim 25 over Sheffer and Cisneros

  • Prior Art Relied Upon: Sheffer (Patent 5,844,522) and Cisneros (Patent 5,774,829).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner presented this ground contingently, arguing that if the Patent Trial and Appeal Board found Sheffer alone insufficient to teach that the "resulting information is dependent on geographical information in each of the first and second location information," then the combination with Cisneros would render the claim obvious. Sheffer was argued to disclose all other claim elements. Cisneros was introduced for its teaching of improving location accuracy by averaging two distinct location estimates (e.g., from uncoordinated beacon signals and GPS), a process that makes the final result mathematically dependent on both inputs.
    • Motivation to Combine: A person of ordinary skill in the art (POSITA), seeking to improve the accuracy of the location system described in Sheffer, would have been motivated to combine it with Cisneros’s explicit teaching of averaging location estimates derived from different techniques. Petitioner asserted this would be a natural and logical extension of Sheffer's own disclosure of comparing results and averaging results from the same technique to improve accuracy.
    • Expectation of Success: Both Sheffer and Cisneros address the same technical problem of mobile device location using similar principles, making their combination predictable and straightforward for a POSITA with a high expectation of success.

Ground 3: Obviousness of Claim 26 over Sheffer, Cisneros, and Sanderford

  • Prior Art Relied Upon: Sheffer (Patent 5,844,522), Cisneros (Patent 5,774,829), and Sanderford (Patent 5,717,406).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground addressed dependent claim 26, which adds the step of "second obtaining, from an additional one or more of the location evaluators, additional location information." Petitioner argued this requires a third distinct location evaluator. The combination of Sheffer and Cisneros was asserted to provide the base system of claim 25. Sanderford was introduced to teach the required third location evaluator. Sanderford discloses a location technique using a neural network that processes Time-of-Arrival (TOA) and Relative-Time-of-Arrival (RTOA) data, which Petitioner contended constitutes the required "additional... location evaluator."
    • Motivation to Combine: A POSITA would be motivated to add Sanderford’s technique to the Sheffer/Cisneros system to create a more robust and accurate location system. Sanderford’s neural network is specifically designed to improve accuracy in environments with multipath signal distortion (e.g., urban areas), a known problem where Sheffer's azimuth-based system could be inaccurate. Adding a technique that mitigates this known issue would have been an obvious way to improve the overall system, especially for use in emergency services.
    • Expectation of Success: The combination was argued to be predictable. Sanderford's technique is compatible because it also produces latitude/longitude coordinates and is explicitly described as being usable with other methods like triangulation, which is taught by Sheffer.

4. Key Claim Construction Positions

  • "mobile station location evaluator": Petitioner argued this term is a means-plus-function term subject to 35 U.S.C. §112, ¶ 6.
    • Function: "determining [a] mobile station location."
    • Structure: Petitioner identified the corresponding structure in the ’484 patent’s specification as a "location hypothesizing model (FOM) implemented on or by a location center or mobile base station."
    • Importance: This construction was critical to Petitioner's arguments, as it permitted mapping the functionally distinct software modules and processing techniques disclosed in the prior art (e.g., Sheffer's azimuth and RSSI routines) to the claimed "evaluator" structures.

5. Relief Requested

  • Petitioner requested the institution of an inter partes review and the cancellation of claims 25 and 26 of the ’484 patent as unpatentable.