Cisco Systems Inc v. XR Communications LLC

1. Case Identification

• Case #: IPR2018-00763
• Patent #: 7,729,728
• Filed: March 15, 2018
• Petitioner(s): Cisco Systems, Inc.
• Patent Owner(s): XR Communications LLC
• Challenged Claims: 16

2. Patent Overview

• Title: Wireless Communication System Using Smart Antennas
• Brief Description: The ’728 patent describes a wireless communication system that uses a smart antenna at an access point to selectively cause a receiving device to switch its operative association from one transmitted beam to another. The technology aims to effectively manage beam switching for mobile client devices.

3. Grounds for Unpatentability

Ground 1: Obviousness over Alastalo and Antonio - Claim 16 is obvious over Alastalo in view of Antonio.

• Prior Art Relied Upon: Alastalo (Application # 2004/0066762) and Antonio (Patent 6,208,858).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Alastalo taught a wireless communication system with access points using a "smart antenna arrangement" (disclosed as a phased-array antenna) and a transceiver to transmit multiple directed data beams. This disclosed the basic structure of the access point in claim 16. Petitioner asserted that Antonio addressed the known problem of dropped calls for mobile users in such beam-based systems by teaching a method for a communication station (e.g., an access point) to manage beam handoffs. Antonio’s method involved the access point actively probing a user device by sending a message (BMM) listing available beams, receiving an uplink message (PSMM) from the device with measured beam strengths, and then determining if the device should switch to a different, stronger beam to maintain connectivity.
  • Motivation to Combine: Petitioner contended a person of ordinary skill in the art (POSITA) would combine these references for several reasons. Both are analogous art concerning wireless systems with directed beams. A POSITA implementing Alastalo’s system would recognize the problem of maintaining connectivity for mobile users and would look to solutions like Antonio’s to reduce call-dropping rates. Antonio’s technique of providing alternative beams and managing handoffs based on signal strength was presented as a known and desirable improvement for multi-beam systems like Alastalo's.
  • Expectation of Success: The combination was argued to be a predictable application of Antonio’s beam handoff and selection method to Alastalo’s foundational beamforming system, yielding the expected benefits of improved connection reliability and reduced dropped calls for mobile devices.

Ground 2: Obviousness over Alastalo, Antonio, and WTEC Report - Claim 16 is obvious over Alastalo in view of Antonio and WTEC Report.

• Prior Art Relied Upon: Alastalo (Application # 2004/0066762), Antonio (Patent 6,208,858), and the WTEC Report ("Smart Antennas," Chapter 6 of WTEC PANEL REPORT ON WIRELESS TECHNOLOGIES AND INFORMATION NETWORKS, July 2000).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground relied on the same core combination of Alastalo and Antonio as Ground 1 but added the WTEC Report to support an alternative, more specific construction of "phased array antenna." Petitioner argued that while Alastalo taught a generic "smart antenna," the WTEC Report explicitly described the two basic types of smart antennas known at the time: the "phased array" and the "adaptive antenna array." The WTEC Report explained that phased arrays use narrow "pencil beams," which directly aligned with Alastalo's stated goal of using narrow beams to reduce interference.
  • Motivation to Combine: A POSITA implementing Alastalo’s system, which relied on a well-known "smart antenna," would be motivated to consult a reference like the WTEC Report for implementation details. The report presented the phased array antenna as one of a finite number (two) of predictable solutions, making its selection an "obvious to try" design choice. Further motivation arose from the technical advantages described in the WTEC Report, such as the well-developed signal processing algorithms for phased arrays and their ability to produce the narrow beams desired in Alastalo's system.
  • Expectation of Success: Petitioner asserted a high expectation of success, as phased array antennas were well-understood and widely used in wireless systems prior to the patent's priority date. The substitution of Alastalo’s generic smart antenna with the specific phased array antenna described in the WTEC Report was a simple substitution of one known element for another to obtain predictable results.

4. Key Claim Construction Positions

• Petitioner argued that the only term requiring potential construction was "phased array antenna."
• Petitioner presented three positions:
  • No Construction Necessary: The term's meaning was not in dispute, as both parties in related litigation agreed it refers to an antenna composed of elements that transmits beams whose direction is controlled by changing signal phases.
  • Proposed Construction: If construction were deemed necessary, Petitioner proposed adopting the Patent Owner’s own construction from co-pending litigation: "array of antenna elements that transmits beams by changing the phases of the signals at the antenna elements."
  • Alternative Construction: As an alternative, Petitioner proposed that the term be construed as a term of art meaning an array that transmits beams by changing only the phases, and not the amplitudes, of the signals. This more restrictive construction formed the basis for the arguments presented in Ground 2.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial would be inappropriate.
• It contended that denial under §325(d) was not warranted because the primary prior art references (Alastalo, Antonio, and the WTEC Report) were not applied or cited by the Examiner during the original prosecution.
• It also argued against discretionary denial under §314(a), noting that while another IPR existed for the ’728 patent (IPR2018-00726), Petitioner Cisco was not a party to that proceeding, meaning the "same petitioner" factor was not implicated.

6. Relief Requested

• Petitioner requested the institution of an inter partes review and the cancellation of claim 16 of the ’728 patent as unpatentable.