Patents by Inventor Dwight Daugherty

Dwight Daugherty 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: 8125241
    Abstract: In described embodiments, automatic de-emphasis setting is provided for driving a capacitive backplane. Line impedance and line length of a transmission (TX) device are measured that form a load impedance of a driver. For some exemplary embodiments, the line impedance is predominantly a line capacitance, and such embodiments detect this capacitance. Measured line impedance is converted to a control signal (such as, for example, a three bit digital control signal) which automatically sets the de-emphasis of the TX stage. With the amount of capacitance and the length of the transmission line, the appropriate de-emphasis settings might be determined, and such de-emphasis setting be applied by the transmitter to the driver to compensate for transmission line effects.
    Type: Grant
    Filed: March 17, 2010
    Date of Patent: February 28, 2012
    Assignee: LSI Corporation
    Inventors: Roger Fratti, Dwight Daugherty
  • Patent number: 8045608
    Abstract: In described embodiments, an adaptive equalizer employed by a receiver in a communication channel, such as Fibre Channel, employs pattern recognition. When a repeating pattern, such as an IDLE or ARBFF pattern, is employed by a standard to, for example, maintain a communication link, an equalizer of the receiver might adaptively set its equalizer parameters based on characteristics of the signal energy of the repeating pattern rather than adaptively set its equalizer parameters based on characteristics of the signal energy of generally random user data carried on the link. Pattern recognition by the receiver allows for maintaining adaptive equalizer parameters at settings preferred for data detection of the typical random data, improving data detection performance of the receiver when the channel transitions from a preset or synchronization repeating pattern to a user random data pattern.
    Type: Grant
    Filed: July 30, 2008
    Date of Patent: October 25, 2011
    Assignee: Agere Systems Inc.
    Inventors: Xingdong Dai, Geoffrey Zhang, Max Olsen, Dwight Daugherty, Gary Schiessler, Mohammad Mobin, Lane Smith, Dennis Farley
  • Patent number: 8045609
    Abstract: In described embodiments, an adaptive equalizer employed by a receiver in a communication channel, such as Fiber Channel, employs pattern recognition. When a repeating pattern, such as an IDLE or ARBFF pattern, is employed by a standard to, for example, maintain a communication link, an equalizer of the receiver might adaptively set its equalizer parameters based on characteristics of the signal energy of the repeating pattern rather than adaptively set its equalizer parameters based on characteristics of the signal energy of generally random user data carried on the link. Pattern recognition by the receiver allows for maintaining adaptive equalizer parameters at settings preferred for data detection of the typical random data, improving data detection performance of the receiver when the channel transitions from a preset or synchronization repeating pattern to a user random data pattern.
    Type: Grant
    Filed: July 30, 2008
    Date of Patent: October 25, 2011
    Assignee: Agere Systems Inc.
    Inventors: Xingdong Dai, Geoffrey Zhang, Max Olsen, Dwight Daugherty
  • Publication number: 20110080237
    Abstract: In described embodiments, automatic de-emphasis setting is provided for driving a capacitive backplane. Line impedance and line length of a transmission (TX) device are measured that form a load impedance of a driver. For some exemplary embodiments, the line impedance is predominantly a line capacitance, and such embodiments detect this capacitance. Measured line impedance is converted to a control signal (such as, for example, a three bit digital control signal) which automatically sets the de-emphasis of the TX stage. With the amount of capacitance and the length of the transmission line, the appropriate de-emphasis settings might be determined, and such de-emphasis setting be applied by the transmitter to the driver to compensate for transmission line effects.
    Type: Application
    Filed: March 17, 2010
    Publication date: April 7, 2011
    Inventors: Roger Fratti, Dwight Daugherty
  • Publication number: 20100027606
    Abstract: In described embodiments, an adaptive equalizer employed by a receiver in a communication channel, such as Fibre Channel, employs pattern recognition. When a repeating pattern, such as an IDLE or ARBFF pattern, is employed by a standard to, for example, maintain a communication link, an equalizer of the receiver might adaptively set its equalizer parameters based on characteristics of the signal energy of the repeating pattern rather than adaptively set its equalizer parameters based on characteristics of the signal energy of generally random user data carried on the link. Pattern recognition by the receiver allows for maintaining adaptive equalizer parameters at settings preferred for data detection of the typical random data, improving data detection performance of the receiver when the channel transitions from a preset or synchronization repeating pattern to a user random data pattern.
    Type: Application
    Filed: July 30, 2008
    Publication date: February 4, 2010
    Applicant: Agere Systems, Inc.
    Inventors: Xingdong Dai, Geoffrey Zhang, Max Olsen, Dwight Daugherty
  • Publication number: 20100027611
    Abstract: In described embodiments, an adaptive equalizer employed by a receiver in a communication channel, such as Fibre Channel, employs pattern recognition. When a repeating pattern, such as an IDLE or ARBFF pattern, is employed by a standard to, for example, maintain a communication link, an equalizer of the receiver might adaptively set its equalizer parameters based on characteristics of the signal energy of the repeating pattern rather than adaptively set its equalizer parameters based on characteristics of the signal energy of generally random user data carried on the link. Pattern recognition by the receiver allows for maintaining adaptive equalizer parameters at settings preferred for data detection of the typical random data, improving data detection performance of the receiver when the channel transitions from a preset or synchronization repeating pattern to a user random data pattern.
    Type: Application
    Filed: July 30, 2008
    Publication date: February 4, 2010
    Applicant: Agere Systems, Inc.
    Inventors: Xingdong Dai, Geoffrey Zhang, Gary Schiessler, Dwight Daugherty, Mohammad Mobin, Lane Smith, Dennis Farley, Max Olsen
  • Patent number: 5568094
    Abstract: An apparatus and method is provided that uses a simple voltage ratio technique to supply specific voltages to a voltage variable attenuator, and the gates of a GaAs RF power amplifier in order to control the efficiency of the amplifier. The output of the power amplifier is sampled and then fed back to the variable voltage attenuator as a control signal. A ratio portion of the control signal is then used to control the gate biases of the power amplifier. When the power requirements are less than maximum, the voltage ratio will become more negative, resulting in less current. As the RF output increases, the voltage ratio will become more positive. Therefore, as the DC voltage varies, the power amplifier's output power will vary accordingly providing the desired output power with enhanced efficiency.
    Type: Grant
    Filed: December 15, 1994
    Date of Patent: October 22, 1996
    Assignee: AT&T Corp.
    Inventors: John W. Bowen, Dwight Daugherty, Stuart H. Wemple, Melvin West, Jr.