PTAB

IPR2016-01347

Samsung Electronics Co Ltd v. Evolved Wireless LLC

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Method and Apparatus for Performing Random Access Procedure in a Mobile Communication System
  • Brief Description: The ’373 patent describes a method for managing a random access procedure during the handover of a mobile terminal from a source base station to a target base station. The disclosed method aims to reduce handover delays and the probability of collision by having the target base station provide dedicated preamble information to the mobile terminal via the source base station.

3. Grounds for Unpatentability

Ground 1: Claims 1-10, 12-13, 15-21, and 23-24 are obvious over Etemad in view of Son.

  • Prior Art Relied Upon: Etemad (Patent 7,693,517) and Son (Patent 7,570,618).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Etemad disclosed a handover method in a wireless system where a target base station reserves a contention-free ranging channel for a mobile station and forwards this information through the serving base station. This process, however, did not explicitly teach assigning a dedicated preamble (or ranging code) to the specific mobile terminal. Son allegedly cured this deficiency by teaching the assignment of a specific, dedicated "ranging code" to a mobile station during handover to enable a "fast handover." The combination of Etemad's handover framework with Son's assignment of a dedicated ranging code allegedly rendered the key limitations of the independent claims obvious, such as receiving access information that includes a dedicated preamble determined by the target base station.
    • Motivation to Combine: A POSITA would combine Etemad and Son to implement a faster and more efficient handover. Son explicitly taught that assigning a dedicated ranging code allows for a "fast handover." Petitioner contended a POSITA would have understood that this speed increase resulted from reducing contention among mobile stations for ranging codes. Therefore, a POSITA would have been motivated to modify Etemad's process to include Son's teaching of assigning a dedicated ranging code to increase handover speed and network efficiency.
    • Expectation of Success: Petitioner asserted a POSITA would have had a high expectation of success because both Etemad and Son described handover methods within the same technical framework (IEEE 802.16 "WiMax" protocol), making the proposed modification straightforward and predictable.

Ground 2: Claims 6 and 19 are obvious over Etemad and Son, in view of WiMax-2004.

  • Prior Art Relied Upon: Etemad (Patent 7,693,517), Son (Patent 7,570,618), and WiMax-2004 (IEEE Std. 802.16-2004).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground built upon the combination of Etemad and Son to address claims requiring that the access information include transmission characteristics related to frequency and time. Petitioner argued that while Etemad and Son taught using a reserved ranging channel, the WiMax-2004 standard, which Etemad's system was based on, explicitly defined how such channels were implemented. WiMax-2004 specified that ranging channels in an OFDMA system consist of a set of subcarrier frequencies used during a defined time period (a specific range of symbol offsets). Therefore, implementing the reserved ranging channel from Etemad/Son according to the WiMax-2004 standard would inherently provide the claimed frequency and time characteristics.
    • Motivation to Combine: A POSITA implementing the handover system of Etemad and Son, which both operate in the context of WiMax, would have been motivated to consult the official WiMax-2004 standard for implementation details. Conforming to the standard was necessary to ensure interoperability with other WiMax network components.
    • Expectation of Success: Success would be expected, as this combination represented applying the explicit teachings of a governing technical standard to implement a feature described in the primary references.

Ground 3: Claim 25 is obvious over Etemad and Son, in view of Petrovic.

  • Prior Art Relied Upon: Etemad (Patent 7,693,517), Son (Patent 7,570,618), and Petrovic (Patent 7,508,792).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground addressed claim 25, which specified that the source and target base stations are "enhanced Node B" (eNB) stations within an "Evolved Universal Mobile Telecommunication System" (E-UMTS). The base combination of Etemad and Son taught a fast handover method in a WiMax context. Petrovic was introduced because it disclosed an E-UMTS architecture that utilized "enhanced base stations (NodeB+s)," which Petitioner argued were equivalent to the claimed eNBs.
    • Motivation to Combine: Petitioner argued that a stated goal of Petrovic was to reduce "handover delay" in its E-UMTS system. A POSITA seeking to achieve this goal would have been motivated to implement the fast, contention-free handover procedure from the combination of Etemad and Son into the E-UMTS architecture of Petrovic. Both systems involved handover between base stations and employed random access procedures, making the integration logical and beneficial for achieving Petrovic's stated objectives.
    • Expectation of Success: The combination was presented as predictable because it applied a known technique (fast handover) to a similar system (E-UMTS instead of WiMax) to obtain a predictable improvement (reduced handover delay).

4. Key Claim Construction Positions

  • "random access procedure": Petitioner argued this term should be construed broadly enough to encompass the "initial ranging procedure" used in WiMax systems. This construction was asserted to be consistent with the ’373 patent’s specification, which explicitly stated its applicability to Mobile WiMax, and supported by other prior art references that used the terms interchangeably.
  • "handover": Petitioner argued against Patent Owner's proposed construction in co-pending litigation that would limit "handover" to only "hard" or "break-before-make" handovers. Petitioner contended that the term should be construed more broadly to mean the "transfer of a terminal's connection with a source base station to a target base station," without such a limitation, as the intrinsic evidence did not disavow other known handover types like soft handovers.
  • "target base station": Petitioner argued this term needs no construction but, if construed, should not be limited to a base station that is determined solely by the source base station, as proposed by the Patent Owner.

5. Relief Requested

  • Petitioner requested institution of an inter partes review and cancellation of claims 1-10, 12-13, 15-21, and 23-25 of the ’373 patent as unpatentable.