PTAB

IPR2018-01722

Cisco Systems Inc v. TracBeam LLC

Log In
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 is designed to be incorporated into existing commercial wireless telephony systems.

3. Grounds for Unpatentability

Ground 1: Claim 57 is obvious over Sheffer in view of Dunn

  • Prior Art Relied Upon: Sheffer (Patent 5,844,522) and Dunn (Patent 5,659,596).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Sheffer, the primary reference, disclosed the core limitations of claim 57. Sheffer described a wireless network-based location system that used a communication and dispatch center (CDC) to determine a mobile phone's location. Petitioner mapped Sheffer’s system to the claim by asserting that Sheffer disclosed two independent "mobile station location evaluators": a first evaluator using an azimuth triangulation technique and a second evaluator using a Received Signal Strength Information (RSSI) technique. Sheffer further taught comparing the results of these independent techniques to determine a final resulting location and an associated "confidence level," which Petitioner argued met the claim limitation of determining resulting location information that is dependent on values from both evaluators and includes data indicative of a likelihood (the confidence level). Petitioner contended that Dunn was necessary to render obvious the claim’s requirement for a timestamp. While Sheffer disclosed timestamps associated with raw data collection, Petitioner argued Dunn explicitly taught storing a timestamp with the final location information to ensure users had the most recent location data available.
    • Motivation to Combine: A POSITA would combine Dunn’s timestamping method with Sheffer’s location system for several reasons. It would allow emergency responders to verify the currency of location data, track the performance and response times of emergency services, and predict the trajectory of a moving target by analyzing a series of time-stamped locations.
    • Expectation of Success: Because both Sheffer and Dunn addressed similar cellular communication and location-finding technologies, Petitioner asserted a POSITA would have had a reasonable expectation of success in combining their teachings.

Ground 2: Claim 59 is obvious over Sheffer, Dunn, and Singer

  • Prior Art Relied Upon: Sheffer (Patent 5,844,522), Dunn (Patent 5,659,596), and Singer (Patent 5,485,163).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground built upon the combination of Sheffer and Dunn for the limitations of claim 57, on which claim 59 depends. Claim 59 added the limitation of "transmitting said resulting location estimate on a communications network to a destination requesting the location of the mobile station." Petitioner argued that while Sheffer taught transmitting location coordinates to a follow-up vehicle, it did not explicitly disclose that the vehicle was a "requesting" destination. Singer was introduced to supply this missing element. Singer described a system where a "requesting subscriber" could remotely activate a portable locator unit and have the determined location forwarded back to them. The location information could be formatted for the specific device used by the subscriber, such as a pager or cellular telephone.
    • Motivation to Combine: A POSITA would combine Singer’s teachings with the Sheffer/Dunn system to enhance its utility for emergency services. This would enable first responders, equipped with mobile units as taught by Dunn, to actively request location information from a central system like Sheffer’s CDC. This is particularly useful for tracking a target in areas inaccessible to vehicles, an improvement over Sheffer’s disclosure of transmitting data primarily to a vehicle-based unit. The combination would create a more flexible and effective emergency response system.
    • Expectation of Success: The proposed combination involved integrating known network functionalities (requesting and forwarding data) into a known type of location system, which would have been a predictable and straightforward task for a POSITA.

4. Key Claim Construction Positions

  • "mobile station location evaluator": Petitioner argued this is a means-plus-function term under 35 U.S.C. §112, ¶ 6. The claimed function was proposed as "determining [a] mobile station location." The corresponding structure identified in the ’484 patent’s specification was a "location hypothesizing model (FOM) implemented on or by a location center or mobile base station." This construction was central to Petitioner’s ability to map Sheffer's distinct azimuth triangulation and RSSI techniques to the claimed first and second "evaluators."
  • "data indicative of one of: an error and a likelihood": Petitioner contended this phrase should be construed to mean "data indicative of an error or a likelihood," not requiring both. This interpretation was based on the specification describing "confidence" as a value "indicating a likelihood" and an estimated "error" as a substitute for a confidence field. This construction allowed Sheffer's "confidence level" to satisfy the "likelihood" limitation of the claim.