Patents by Inventor Richard T. Chang

Richard T. Chang 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: 8774041
    Abstract: A first network device can implement functionality to establish a proximity-based wireless connection with a second network device. It can be determined whether the second network device is within a threshold detection distance from the first network device based on a signal strength associated with RF signals received from the second network device or based on detecting RF saturation at the first network device. Device credentials associated with the first network device can be transmitted to the second network device at a reduced transmit power level in response to determining that the second network device is within the threshold detection distance from the first network device. A communication link can be established between the first network device and the second network device based, at least in part, on the device credentials associated with the first network device and device credentials received from the second network device.
    Type: Grant
    Filed: March 2, 2012
    Date of Patent: July 8, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Enis Akay, Richard T. Chang, Meng-Ta Hsu, Yu-Chang Hu, Philip F. Kearney
  • Publication number: 20130229930
    Abstract: A first network device can implement functionality to establish a proximity-based wireless connection with a second network device. It can be determined whether the second network device is within a threshold detection distance from the first network device based on a signal strength associated with RF signals received from the second network device or based on detecting RF saturation at the first network device. Device credentials associated with the first network device can be transmitted to the second network device at a reduced transmit power level in response to determining that the second network device is within the threshold detection distance from the first network device. A communication link can be established between the first network device and the second network device based, at least in part, on the device credentials associated with the first network device and device credentials received from the second network device.
    Type: Application
    Filed: March 2, 2012
    Publication date: September 5, 2013
    Applicant: QUALCOMM ATHEROS, INC.
    Inventors: Enis Akay, Richard T. Chang, Meng-Ta Hsu, Yu-Chang Hu, Philip F. Kearney
  • Patent number: 8514595
    Abstract: Methods of calibrating and operating a switching power supply in an electronic system are disclosed. A switching power supply is calibrated to determine a switching frequency. Harmonic frequencies that are multiples of the switching frequency are determined. A further determination is made as to whether any of the harmonic frequencies falls within one of one or more frequency bands of interest. A second switching frequency is determined such that none of its corresponding harmonic frequencies falls within a frequency band of interest. During operation of the system, the switching power supply is configured to operate at the second switching frequency if operation occurs within one of the frequency bands of interest.
    Type: Grant
    Filed: August 4, 2009
    Date of Patent: August 20, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Paul J. Husted, Richard T. Chang
  • Patent number: 8447249
    Abstract: This disclosure is directed to systems and methods that provide control of transmitted signal power that do not require the use of an external power detector. By determining the expected transmit power based upon conditions such as temperature or voltage, the settings of the transmitters amplifier can be adjusted to more closely match the desired transmit power.
    Type: Grant
    Filed: March 9, 2011
    Date of Patent: May 21, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Tuofu Lu, Kai Shi, Richard T. Chang, Sang-Min Lee, Joe I. Jamp, Paul J. Husted, Praveen Dua
  • Patent number: 8135357
    Abstract: A switchable inductor-capacitor-inductor (L-C-L) network, which includes an integrated T/R switch, can advantageously bridge a PA and an LNA of a wireless device. The first inductor can function as an RF choke that provides power to the PA. In one embodiment, the first inductor can be advantageously implemented using the bond wires already attached to the PA, thereby requiring no additional inductors to provide the integrated T/R switch and minimizing use of valuable silicon area. The second inductor can function as a source inductor for and cancel an input parasitic capacitance of the LNA. A set of capacitors can act as blocking capacitors to provide DC isolation between the LNA and the PA, thereby protecting the LNA from high voltages. The L-C-L network can also advantageously function as an impedance matching network for at least one of the PA and the LNA.
    Type: Grant
    Filed: December 13, 2005
    Date of Patent: March 13, 2012
    Assignee: Qualcomm Atheros, Inc.
    Inventors: Richard T. Chang, David Weber
  • Patent number: D335702
    Type: Grant
    Filed: July 2, 1991
    Date of Patent: May 18, 1993
    Assignee: Information Scan Technology, Inc.
    Inventor: Richard T. Chang