PTAB

IPR2018-00021

Broadcom Ltd v. Tessera Advanced Technologies Inc

Log In
Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Radio Device with Self-Tuning Receiving Part
  • Brief Description: The ’167 patent relates to radio communication devices, specifically a device and method for automatically tuning a selective, high-frequency amplifier stage. The invention aims to compensate for frequency variations caused by manufacturing tolerances and temperature changes by using a processor-controlled system to adjust an anti-resonant frequency selective circuit.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claims 1 and 4 by Cho

  • Prior Art Relied Upon: Cho (Korean Patent Application No. 20-1989-0019766).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Cho, which discloses an automatic burst gain control circuit for a video device, teaches every element of claims 1 and 4. Cho’s tuner, including an RF amplifier followed by an IF tuning unit, was alleged to be the claimed "frequency selective stage" with an "anti-resonant frequency selective circuit." The demodulating unit and color burst detector in Cho were asserted to meet the "level detector" limitation. The varactor diode in Cho's IF tuning unit, which changes capacitance based on an error voltage, was mapped to the claimed "variation element." Finally, Petitioner contended that Cho’s microcomputer inherently performs the functions of the claimed "storage element" and "processor" by comparing voltages, generating a control magnitude (error voltage), and adjusting the varactor diode to achieve a standard burst level.

Ground 2: Obviousness of Claims 1-5 over Cho in view of Dobrovolny and Vilard

  • Prior Art Relied Upon: Cho, Dobrovolny (Patent 4,571,560), and Vilard (Patent 4,924,300).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner asserted that Cho discloses most limitations of the challenged claims. To the extent Cho’s varactor diode-based tuning circuit was found not to meet the limitation of a "variation element comprising a plurality of reactive elements and a connection network," this feature was obvious from Dobrovolny and Vilard. Dobrovolny teaches problems associated with varactor-tuned frequency converters, providing a reason to replace such a circuit. Vilard explicitly teaches an alternative method for tuning a resonant circuit using a network of switched capacitors controlled by a memory/counter that responds to an error signal. This switched-capacitor network directly corresponds to the claimed variation element. Dependent claims 2, 3, and 5 were argued to be obvious as they recite features explicitly taught by Vilard’s switched-capacitor circuit, such as using a counter (claim 2) and an inductor in parallel with multiple capacitors (claims 3 and 5).
    • Motivation to Combine: A POSITA would combine these references to solve a known problem with a known solution. Dobrovolny identified known deficiencies in varactor-based tuners like the one in Cho. Vilard provided a well-understood alternative using a switched-capacitor network. Since all three references relate to tuning circuits in television receivers, a POSITA would have been motivated to replace Cho’s varactor diode with Vilard’s more robust switched-capacitor design to improve performance and reliability.
    • Expectation of Success: A POSITA would have a high expectation of success because it involved substituting one known type of tunable filter circuit for another to achieve improved, predictable results within the same technological field.

Ground 3: Obviousness of Claims 1-5 over Vilard in view of Cho or Dobrovolny

  • Prior Art Relied Upon: Vilard, Cho, and Dobrovolny.
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Vilard serves as the primary reference, teaching the core of the invention: an anti-resonant "cloche" circuit tuned by a network of switched capacitors (the "variation element"), a frequency discriminator (the "level detector"), and a processing circuit that stores a control magnitude to adjust the tuning. The primary element allegedly not explicitly shown in Vilard is the "amplification stage" preceding the frequency selective circuit. Petitioner contended that adding such a stage would have been obvious. Both Cho and Dobrovolny explicitly disclose using an RF amplifier or preamplifier at the input of their respective filter circuits. The ’167 patent itself acknowledged that high-frequency amplifier stages were "well known" in the art.
    • Motivation to Combine: A POSITA would combine an input amplifier with Vilard’s tuning circuit for the simple and well-known purpose of amplifying the incoming RF signal before filtering and demodulation. This was a standard design practice in television receivers, as evidenced by Cho and Dobrovolny. The motivation was to ensure adequate signal strength for subsequent processing, a fundamental goal in receiver design.
    • Expectation of Success: The combination was a routine and predictable integration of standard components (an amplifier and a filter) to perform their conventional functions. A POSITA would have expected the combination to work without any undue experimentation.

4. Relief Requested

  • Petitioner requests the institution of an inter partes review and a final written decision canceling claims 1-5 of the ’167 patent as unpatentable.