Apple Inc v. Mobile Telecommunications Technologies LLC

1. Case Identification

• Case #: IPR2014-01035
• Patent #: 5,659,891
• Filed: June 27, 2014
• Petitioner(s): Apple Inc.
• Patent Owner(s): Mobile Telecommunications Technologies, LLC
• Challenged Claims: 1-5

2. Patent Overview

• Title: Multicarrier Techniques in Bandlimited Channels
• Brief Description: The ’891 patent describes methods and systems for multicarrier modulation using co-located transmitters to increase transmission capacity for mobile paging and digital communication. The technology aims to operate within a single, mask-defined channel consistent with FCC emission limits.

3. Grounds for Unpatentability

Ground 1: Anticipation by Petrovic - Claims 1-5 are anticipated by Petrovic under 35 U.S.C. §102.

• Prior Art Relied Upon: Petrovic et al., "Permutation Modulation for Advanced Radio Paging," IEEE Proceedings of Southeastcon '93 (Apr. 1993) ("Petrovic").
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Petrovic, a paper co-authored by two inventors of the ’891 patent, describes a nearly identical multicarrier system for paging networks. The petition asserted Petrovic discloses the key limitation that led to the patent’s allowance: the frequency difference between the outermost carrier and the channel’s band edge being greater than half the frequency difference between adjacent carriers. Petrovic explicitly teaches 7.5 kHz guard bands and 5 kHz spacing between subcarriers; 7.5 kHz is greater than half of 5 kHz (2.5 kHz). Petrovic also allegedly discloses overlapping adjacent carriers (claim 2) and a system where outputs of subtransmitters are combined and sent to a common antenna, meeting the co-location requirement of claim 5.
  • Key Aspects: The argument focused on Petrovic disclosing the very feature the Examiner identified as missing from the prior art of record during original prosecution.

Ground 2: Obviousness over Petrovic Combination - Claim 5 is obvious over Petrovic in view of Raith and Alakija under 35 U.S.C. §103.

• Prior Art Relied Upon: Petrovic, Raith (WO 1989/008355), and Alakija ("A Mobile Base Station Phased Array Antenna," 1992 IEEE Conference).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground was presented as an alternative if the term "plurality of transmitters" is construed to require physically separate units, a construction under which Petrovic’s specific experimental setup (transmitters seven miles apart) would not anticipate. Petitioner argued Petrovic teaches the base multicarrier paging system. Raith teaches cellular network design, including the common practice of co-locating base station transmitters to service adjacent cells. Alakija teaches combining the outputs of co-located transmitters into a single, efficient cylindrical array antenna.
  • Motivation to Combine: A person of ordinary skill in the art (POSITA) would combine Petrovic’s paging system with Raith’s well-known cellular architecture to expand the system’s geographic coverage. To implement Raith’s co-located transmitters efficiently, a POSITA would be motivated to use Alakija’s single-antenna solution to achieve hardware savings, lower manufacturing and installation costs, and reduce the system’s physical footprint.
  • Expectation of Success: A POSITA would have a reasonable expectation of success because combining these references involved applying established principles of cellular network design (Raith) and antenna consolidation (Alakija) to a known modulation scheme (Petrovic), all within the predictable field of wireless communications.

Ground 3: Anticipation by Cimini - Claims 1-5 are anticipated by Cimini under 35 U.S.C. §102.

• Prior Art Relied Upon: Cimini, "Analysis and Simulation of a Digital Mobile Channel Using Orthogonal Frequency Division Multiplexing," 33 IEEE Transactions on Communications 665 (Jul. 1985) ("Cimini").

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner contended that Cimini’s disclosure of an Orthogonal Frequency Division Multiplexing (OFDM) system teaches every element of the challenged claims. Cimini describes transmitting multiple subcarriers in a "strictly band-limited" channel and explicitly permits the spectra of individual subchannels to overlap (claim 2). For the key guard band limitation, Cimini describes a system with guard bands of at least 250 Hz and adjacent carrier spacing of 58.59 Hz. The 250 Hz guard band is more than half the 58.59 Hz spacing. For claim 5, Petitioner argued that Cimini’s transmitter diagram (FIG. 1a) illustrates a multicarrier system where carriers are emanated from a single transmission source (an antenna), satisfying the co-location requirement.

• Additional Grounds: Petitioner asserted an additional obviousness challenge against claim 5 based on Cimini in view of Raith and Alakija, which mirrored the design modification theories presented in Ground 2.

4. Key Claim Construction Positions

• "Single mask-defined, bandlimited channel" (claims 1, 3, 5): Petitioner proposed this term be construed as "a channel confined to a frequency range." This construction was based on an agreement between the parties in co-pending district court litigation and was argued to be consistent with the patent’s description of operating within standard FCC-defined frequency allocations.
• "Plurality of Transmitters" (claim 5): Petitioner argued this term should encompass "a configuration in which multiple carriers are emanated from the same transmission source." This broad interpretation, supported by figures in the ’891 patent, was central to the anticipation arguments where a single antenna transmits multiple carriers.
• "Paging" (claims 1, 3, 5): Petitioner proposed construing "paging" as "a non-limiting descriptive name for the systems in which the methods recited by the Claims may be performed." This construction, allegedly advanced by the Patent Owner in litigation, prevents the term from being a technical limitation and allows prior art from general digital communications (like Cimini) to be applied directly.

5. Relief Requested

• Petitioner requests institution of an inter partes review (IPR) and cancellation of claims 1-5 of Patent 5,659,891 as unpatentable.