Patents by Inventor Chunmig Zhao

Chunmig Zhao 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).

  • Transmit power measurement and control methods and apparatus
    Patent number: 9100921
    Abstract: Embodiments include methods and apparatus for performing transmit power control. A gain application element receives a sequence of digital input samples and a digital gain signal, and combines the digital gain signal with the digital input samples to generate a sequence of gain-compensated digital samples. A power amplifier receives and amplifies an analog version of the gain-compensated digital samples in order to generate an antenna output signal. A feedback path generates an analog feedback signal from the antenna output signal, produces a sequence of digital feedback samples from the analog feedback signal, and generates difference values based on the digital feedback samples. When a specified type of constant modulus symbol is represented in the antenna output symbol, the feedback path accumulates the difference values into an accumulated error value, and produces the digital gain signal from the accumulated error value.
    Type: Grant
    Filed: August 20, 2012
    Date of Patent: August 4, 2015
    Assignee: Apple Inc.
    Inventors: Bing Xu, Mahibur Rahman, Chunmig Zhao
  • TRANSMIT POWER MEASUREMENT AND CONTROL METHODS AND APPARATUS
    Publication number: 20130045773
    Abstract: Embodiments include methods and apparatus for performing transmit power control. A gain application element receives a sequence of digital input samples and a digital gain signal, and combines the digital gain signal with the digital input samples to generate a sequence of gain-compensated digital samples. A power amplifier receives and amplifies an analog version of the gain-compensated digital samples in order to generate an antenna output signal. A feedback path generates an analog feedback signal from the antenna output signal, produces a sequence of digital feedback samples from the analog feedback signal, and generates difference values based on the digital feedback samples. When a specified type of constant modulus symbol is represented in the antenna output symbol, the feedback path accumulates the difference values into an accumulated error value, and produces the digital gain signal from the accumulated error value.
    Type: Application
    Filed: August 20, 2012
    Publication date: February 21, 2013
    Inventors: Bing Xu, Mahibur Rahman, Chunmig Zhao
  • Transmit power measurement and control methods and apparatus
    Patent number: 8249531
    Abstract: Embodiments include methods and apparatus for performing transmit power control. A gain application element receives a sequence of digital input samples and a digital gain signal, and combines the digital gain signal with the digital input samples to generate a sequence of gain-compensated digital samples. A power amplifier receives and amplifies an analog version of the gain-compensated digital samples in order to generate an antenna output signal. A feedback path generates an analog feedback signal from the antenna output signal, produces a sequence of digital feedback samples from the analog feedback signal, and generates difference values based on the digital feedback samples. When a specified type of constant modulus symbol is represented in the antenna output symbol, the feedback path accumulates the difference values into an accumulated error value, and produces the digital gain signal from the accumulated error value.
    Type: Grant
    Filed: October 31, 2008
    Date of Patent: August 21, 2012
    Assignee: Apple, Inc.
    Inventors: Bing Xu, Mahibur Rahman, Chunmig Zhao