Patents by Inventor Alton S. Keel

Alton S. Keel has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7653159
    Abstract: An Automatic Gain Control (AGC) circuit as used in a digital receiver that utilizes a main loop filter that is of a relatively wide bandwidth. A pre-filter, wideband variance is determined from the input digital signal, and a post-filter, narrowband variance is also determined. The wideband and narrowband variances are then compared to determine if the wideband signal power indicates a variance level that is too great to permit normal loop operation. By reapplying this difference in the power levels to the filter output as needed, such as by a scaling operation, the loss in dynamic range is effectively recovered. In a preferred embodiment, an adjustable gain input amplifier feeds an intermediate frequency (IF) signal to an analog-to-digital converter (ADC). The digitized IF signal is then down-converted to a baseband frequency and subjected to digital filtering. A narrowband sample variance (PN) of the digitally filtered (narrowband) data is then determined.
    Type: Grant
    Filed: January 27, 2009
    Date of Patent: January 26, 2010
    Assignee: IPR Licensing, Inc.
    Inventors: Mark J. Takatz, Alton S. Keel, Jr., Stefan Haenggi
  • Publication number: 20090284434
    Abstract: An antenna apparatus, which can increase capacity in a cellular communication system or Wireless Local Area Network (WLAN), such as an 802.11 network, operates in conjunction with a mobile subscriber unit or client station. At least one antenna element is active and located within multiple passive antenna elements. The passive antenna elements are coupled to selectable impedance components for phase control of re-radiated RF signals. Various techniques for determining the phase of each antenna element are supported to enable the antenna apparatus to direct an antenna beam pattern toward a base station or access point with maximum gain, and, consequently, maximum signal-to-noise ratio. By directionally receiving and transmitting signals, multipath fading is greatly reduced as well as intercell interference.
    Type: Application
    Filed: May 5, 2009
    Publication date: November 19, 2009
    Applicant: IPR LICENSING, INC.
    Inventors: Griffin K. Gothard, Alton S. Keel, JR., Christopher A. Snyder, Bing Chiang, Joe T. Richeson, Douglas H. Wood, James A. Proctor, JR., Kenneth M. Gainey
  • Publication number: 20090135971
    Abstract: An Automatic Gain Control (AGC) circuit as used in a digital receiver that utilizes a main loop filter that is of a relatively wide bandwidth. A pre-filter, wideband variance is determined from the input digital signal, and a post-filter, narrowband variance is also determined. The wideband and narrowband variances are then compared to determine if the wideband signal power indicates a variance level that is too great to permit normal loop operation. By reapplying this difference in the power levels to the filter output as needed, such as by a scaling operation, the loss in dynamic range is effectively recovered. In a preferred embodiment, an adjustable gain input amplifier feeds an intermediate frequency (IF) signal to an analog-to-digital converter (ADC). The digitized IF signal is then down-converted to a baseband frequency and subjected to digital filtering. A narrowband sample variance (PN) of the digitally filtered (narrowband) data is then determined.
    Type: Application
    Filed: January 27, 2009
    Publication date: May 28, 2009
    Applicant: InterDigital Technology Corporation
    Inventors: Mark J. Takatz, Alton S. Keel, JR., Stefan Haenggi
  • Patent number: 7528789
    Abstract: An antenna apparatus, which can increase capacity in a cellular communication system or Wireless Local Area Network (WLAN), such as an 802.11 network, operates in conjunction with a mobile subscriber unit or client station. At least one antenna element is active and located within multiple passive antenna elements. The passive antenna elements are coupled to selectable impedance components for phase control of re-radiated RF signals. Various techniques for determining the phase of each antenna element are supported to enable the antenna apparatus to direct an antenna beam pattern toward a base station or access point with maximum gain, and, consequently, maximum signal-to-noise ratio. By directionally receiving and transmitting signals, multipath fading is greatly reduced as well as intercell interference.
    Type: Grant
    Filed: May 8, 2007
    Date of Patent: May 5, 2009
    Assignee: IPR Licensing, Inc.
    Inventors: Griffin K. Gothard, Alton S. Keel, Jr., Christopher A. Snyder, Bing Chiang, Joe T. Richeson, Douglas H. Wood, James A. Proctor, Jr., Kenneth M. Gainey
  • Patent number: 7483500
    Abstract: An Automatic Gain Control (AGC) circuit as used in a digital receiver that utilizes a main loop filter that is of a relatively wide bandwidth. A pre-filter, wideband variance is determined from the input digital signal, and a post-filter, narrowband variance is also determined. The wideband and narrowband variances are then compared to determine if the wideband signal power indicates a variance level that is too great to permit normal loop operation. By reapplying this difference in the power levels to the filter output as needed, such as by a scaling operation, the loss in dynamic range is effectively recovered. In a preferred embodiment, an adjustable gain input amplifier feeds an intermediate frequency (IF) signal to an analog-to-digital converter (ADC). The digitized IF signal is then down-converted to a baseband frequency and subjected to digital filtering. A narrowband sample variance (PN) of the digitally filtered (narrowband) data is then determined.
    Type: Grant
    Filed: April 6, 2006
    Date of Patent: January 27, 2009
    Assignee: IPR Licensing, Inc.
    Inventors: Mark J. Takatz, Alton S. Keel, Jr., Stefan Haenggi
  • Patent number: 7215297
    Abstract: An antenna apparatus, which can increase capacity in a cellular communication system or Wireless Local Area Network (WLAN), such as an 802.11 network, operates in conjunction with a mobile subscriber unit or client station. At least one antenna element is active and located within multiple passive antenna elements. The passive antenna elements are coupled to selectable impedance components for phase control of re-radiated RF signals. Various techniques for determining the phase of each antenna element are supported to enable the antenna apparatus to direct an antenna beam pattern toward a base station or access point with maximum gain, and, consequently, maximum signal-to-noise ratio. By directionally receiving and transmitting signals, multipath fading is greatly reduced as well as intercell interference.
    Type: Grant
    Filed: January 17, 2006
    Date of Patent: May 8, 2007
    Assignee: IPR Licensing, Inc.
    Inventors: Griffin K. Gothard, Alton S. Keel, Jr., Christopher A. Snyder, Bing Chiang, Joe T. Richeson, Douglas H. Wood, James A. Proctor, Jr., Kenneth M. Gainey
  • Patent number: 7046749
    Abstract: An Automatic Gain Control (AGC) circuit as used in a digital receiver that utilizes a main loop filter that is of a relatively wide bandwidth. A pre-filter, wideband variance is determined from the input digital signal, and a post-filter, narrowband variance is also determined. The wideband and narrowband variances are then compared to determine if the wideband signal power indicates a variance level that is too great to permit normal loop operation. By reapplying this difference in the power levels to the filter output as needed, such as by a scaling operation, the loss in dynamic range is effectively recovered. In a preferred embodiment, an adjustable gain input amplifier feeds an intermediate frequency (IF) signal to an analog-to-digital converter (ADC). The digitized IF signal is then down-converted to a baseband frequency and subjected to digital filtering. A narrowband sample variance (PN) of the digitally filtered (narrowband) data is then determined.
    Type: Grant
    Filed: May 1, 2001
    Date of Patent: May 16, 2006
    Assignee: IPR Licensing, Inc.
    Inventors: Mark J. Takatz, Alton S. Keel, Jr., Stefan Haenggi
  • Patent number: 6989797
    Abstract: An antenna apparatus, which can increase capacity in a cellular communication system or Wireless Local Area Network (WLAN), such as an 802.11 network, operates in conjunction with a mobile subscriber unit or client station. At least one antenna element is active and located within multiple passive antenna elements. The passive antenna elements are coupled to selectable impedance components for phase control of re-radiated RF signals. Various techniques for determining the phase of each antenna element are supported to enable the antenna apparatus to direct an antenna beam pattern toward a base station or access point with maximum gain, and, consequently, maximum signal-to-noise ratio. By directionally receiving and transmitting signals, multipath fading is greatly reduced as well as intercell interference.
    Type: Grant
    Filed: December 23, 2003
    Date of Patent: January 24, 2006
    Assignee: IPR Licensing, Inc.
    Inventors: Griffin K. Gothard, Alton S. Keel, Jr., Christopher A. Snyder, Bing Chiang, Joe T. Richeson, Douglas H. Wood, James A. Proctor, Jr., Kenneth M. Gainey
  • Publication number: 20040259597
    Abstract: An antenna apparatus, which can increase capacity in a cellular communication system or Wireless Local Area Network (WLAN), such as an 802.11 network, operates in conjunction with a mobile subscriber unit or client station. At least one antenna element is active and located within multiple passive antenna elements. The passive antenna elements are coupled to selectable impedance components for phase control of re-radiated RF signals. Various techniques for determining the phase of each antenna element are supported to enable the antenna apparatus to direct an antenna beam pattern toward a base station or access point with maximum gain, and, consequently, maximum signal-to-noise ratio. By directionally receiving and transmitting signals, multipath fading is greatly reduced as well as intercell interference.
    Type: Application
    Filed: December 23, 2003
    Publication date: December 23, 2004
    Inventors: Griffin K. Gothard, Alton S. Keel, Christopher A. Snyder, Bing Chiang, Joe T. Richeson, Douglas H. Wood, James A. Proctor, Kenneth M. Gainey
  • Patent number: 6600456
    Abstract: An antenna apparatus which can increase capacity in a cellular communication system. The antenna operates in conjunction with a mobile subscriber unit and provides a plurality of antenna elements. At least one active antenna element is active and essentially centrally located within multiple passive antenna elements. The passive antenna elements are coupled to selectable impedance components. Through proper control of the passive antenna elements, the cellular communication system directs an antenna beam pattern toward an antenna tower of a base station to maximize gain, and, consequently, signal-to-noise ratio. Thus, optimum reception is achieved during, for example, an idle mode which receives a pilot signal. The antenna array creates a beamformer for signals to be transmitted from the mobile subscriber unit, and a directional receiving array to more optimally detect and receive signals transmitted from the base station.
    Type: Grant
    Filed: May 16, 2001
    Date of Patent: July 29, 2003
    Assignee: Tantivy Communications, Inc.
    Inventors: Griffin K. Gothard, Alton S. Keel, Jr., Christopher A. Snyder, Bing Chiang, Joe T. Richeson, Douglas H. Wood, James A. Proctor, Jr., Kenneth M. Gainey
  • Publication number: 20020163979
    Abstract: An Automatic Gain Control (AGC) circuit as used in a digital receiver that utilizes a main loop filter that is of a relatively wide bandwidth. A pre-filter, wideband variance is determined from the input digital signal, and a post-filter, narrowband variance is also determined. The wideband and narrowband variances are then compared to determine if the wideband signal power indicates a variance level that is too great to permit normal loop operation. By reapplying this difference in the power levels to the filter output as needed, such as by a scaling operation, the loss in dynamic range is effectively recovered. In a preferred embodiment, an adjustable gain input amplifier feeds an intermediate frequency (IF) signal to an analog-to-digital converter (ADC). The digitized IF signal is then down-converted to a baseband frequency and subjected to digital filtering. A narrowband sample variance (PN) of the digitally filtered (narrowband) data is then determined.
    Type: Application
    Filed: May 1, 2001
    Publication date: November 7, 2002
    Applicant: Tantivy Communictions, Inc.
    Inventors: Mark J. Takatz, Alton S. Keel, Stefan Haenggi
  • Publication number: 20020008672
    Abstract: An antenna apparatus which can increase capacity in a cellular communication system. The antenna operates in conjunction with a mobile subscriber unit and provides a plurality of antenna elements. At least one active antenna element is active and essentially centrally located within multiple passive antenna elements. The passive antenna elements are coupled to selectable impedance components. Through proper control of the passive antenna elements, the cellular communication system directs an antenna beam pattern toward an antenna tower of a base station to maximize gain, and, consequently, signal-to-noise ratio. Thus, optimum reception is achieved during, for example, an idle mode which receives a pilot signal. The antenna array creates a beamformer for signals to be transmitted from the mobile subscriber unit, and a directional receiving array to more optimally detect and receive signals transmitted from the base station.
    Type: Application
    Filed: May 16, 2001
    Publication date: January 24, 2002
    Applicant: Tantivy Communications, Inc.
    Inventors: Griffin K. Gothard, Alton S. Keel, Christopher A. Snyder, Bing Chiang, Joe T. Richeson, Douglas H. Wood, James A. Proctor, Kenneth M. Gainey