Patents by Inventor Chung-Yao Chang

Chung-Yao 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).

  • Publication number: 20150180562
    Abstract: A wireless communication method applied to a beamformer includes: receiving a plurality of reference information corresponding to a plurality of stations, respectively; calculating an evaluation value for each of the stations according to at least one reference information of the plurality of reference information; and comparing a plurality of evaluation values respectively corresponding to the plurality of stations, to select specific stations from the plurality of stations for performing beamforming.
    Type: Application
    Filed: December 23, 2014
    Publication date: June 25, 2015
    Inventors: Chien-Wei Hsin, Chung-Yao Chang
  • Publication number: 20150156048
    Abstract: A carrier frequency offset (CFO) calibration method for calibrating a CFO of a receiver is proposed. The CFO calibration method includes: receiving at least one CFO estimation value generated by digital CFO estimation; generating a CFO adjustment value according to the at least one CFO estimation value; and adjusting an oscillation frequency of an oscillator of the receiver according to the CFO adjustment value.
    Type: Application
    Filed: November 24, 2014
    Publication date: June 4, 2015
    Inventors: Chih-Yung Wu, Kai-Wei Yen, Chung-Yao Chang
  • Patent number: 9030343
    Abstract: The present invention discloses a communication device and a communication method capable of power calibration. Said communication device comprises: a digital circuit to provide a digital output signal; a detection circuit to perform a predetermined detection and generate a detection result; a control circuit to generate a digital-end and an analog-end gain adjustment signals according to the detection result; a digital-end gain adjustment circuit to adjust the gain of the digital output signal according to the digital-end gain adjustment signal and generate a digital gain-adjusted output signal; a digital-to-analog converter to generate an analog output signal according to the digital gain-adjusted output signal; and an analog circuit to adjust the gain of the analog output signal according to the analog-end gain adjustment signal and generate an analog gain-adjusted output signal, wherein the detection circuit is operable to detect the influence caused by a peripheral factor to the analog circuit.
    Type: Grant
    Filed: June 5, 2014
    Date of Patent: May 12, 2015
    Assignee: Realtek Semiconductor Corporation
    Inventors: Yu-Cheng Chen, Tsung-Hsuan Lee, Chung-Yao Chang
  • Patent number: 8995248
    Abstract: A power adjusting apparatus communicating with a remote terminal is provided. The apparatus includes: a transceiving unit transmitting a plurality of test packets by a plurality of powers; a processing unit coupled to the transceiving unit, and deciding a transmission power for transmitting a subsequent packet according to at least one retransmission number of transmitting the test packets.
    Type: Grant
    Filed: February 14, 2012
    Date of Patent: March 31, 2015
    Assignee: Realtek Semiconductor Corp.
    Inventors: Wei-Hsuan Chang, Chung-Yao Chang, Der-Zheng Liu, Kuang-Yu Yen
  • Publication number: 20150078488
    Abstract: A wireless communication apparatus for coupling to a multi-antenna module comprising a plurality of antennas, the wireless communication apparatus includes: a switching circuit, arranged for selectively changing the connected relations of the plurality of antennas according to a switching signal, so as to make the multi-antenna module generating a plurality of antenna combinations; and a receiving module, coupled to the switching circuit, including: a signal intensity measurement circuit, arranged for measuring signal intensity of a wireless packet received through the plurality of antenna combinations, so as to generate a plurality of measurement results; and an antenna switching determination circuit, during a training state, arranged for choosing a first comparison group comprising at least two antenna combinations from the plurality of antenna combinations for receiving the wireless packet, and determining a better antenna combination according to measurement results of the first comparing group.
    Type: Application
    Filed: September 12, 2014
    Publication date: March 19, 2015
    Inventors: Tsung-Hsuan Lee, Chung-Yao Chang
  • Patent number: 8971462
    Abstract: A channel quality determining circuit includes a receiving circuit and a determining circuit. The receiving circuit is used for receiving a header of at least one packet transmitted in a signal transmitting channel. The determining circuit is coupled to the receiving circuit, and used for determining if a channel quality of the signal transmitting channel satisfies a predetermined quality standard according to the header of at least one packet.
    Type: Grant
    Filed: September 28, 2011
    Date of Patent: March 3, 2015
    Assignee: Realtek Semiconductor Corp.
    Inventor: Chung-Yao Chang
  • Patent number: 8964737
    Abstract: A wireless communication circuit for a wireless communication device having a plurality of antennas is disclosed. The wireless communication circuit includes: a transceiver for receiving and transmitting network packets; a control circuit for controlling the switching circuit to switch the transceiver among the antennas so that the transceiver receives the preamble of a first network packet; and a receiving signal strength detector for detecting the receiving signal strength value of respective antennas in respective receiving periods during the reception of the preamble conducted by the transceiver. If the receiving signal strength value of each antenna is less than a predetermined threshold, the control circuit selects an antenna with the maximum receiving strength value as a target antenna and controls the switching circuit to couple the transceiver to the selected target antenna so that the transceiver receives the rest of the first network packet through the target antenna.
    Type: Grant
    Filed: January 4, 2013
    Date of Patent: February 24, 2015
    Assignee: Realtek Semiconductor Corp.
    Inventors: Tsung-Hsuan Lee, Chung-Yao Chang, Der-Zheng Liu
  • Publication number: 20150042497
    Abstract: The present invention discloses a communication device and a communication method capable of power calibration. Said communication device comprises: a digital circuit to provide a digital output signal; a detection circuit to perform a predetermined detection and generate a detection result; a control circuit to generate a digital-end and an analog-end gain adjustment signals according to the detection result; a digital-end gain adjustment circuit to adjust the gain of the digital output signal according to the digital-end gain adjustment signal and generate a digital gain-adjusted output signal; a digital-to-analog converter to generate an analog output signal according to the digital gain-adjusted output signal; and an analog circuit to adjust the gain of the analog output signal according to the analog-end gain adjustment signal and generate an analog gain-adjusted output signal, wherein the detection circuit is operable to detect the influence caused by a peripheral factor to the analog circuit.
    Type: Application
    Filed: June 5, 2014
    Publication date: February 12, 2015
    Inventors: YU-CHENG CHEN, TSUNG-HSUAN LEE, CHUNG-YAO CHANG
  • Publication number: 20150009904
    Abstract: A channel map generation method includes: performing a power spectrum density detection on a plurality of channels in a frequency band, to generate a first channel map; and performing a first smoothing operation on the first channel map by a first window size to generate a second channel map. The first smoothing operation includes: grouping channels of the first channel map into a plurality of channel groups according to the first window size; and according to the number of good channels or bad channels in each of the channel group, deciding to retain channel determinations in the first channel map of the channel group, or re-designating all the channels of the channel group, so as to generate the second channel map.
    Type: Application
    Filed: December 23, 2013
    Publication date: January 8, 2015
    Applicant: Realtek Semiconductor Corp.
    Inventors: Yan-Yu Chen, Chung-Yao Chang
  • Patent number: 8923790
    Abstract: A wireless communication receiver includes a circuit, an analog-to-digital converter (ADC) and a processing circuit. The circuit receives a wireless signal and outputs an analog signal according to a gain index. The ADC converts the analog signal to a digital signal. The processing circuit adjusts the gain index according to a clipping number of the ADC.
    Type: Grant
    Filed: February 8, 2013
    Date of Patent: December 30, 2014
    Assignee: Realtek Semiconductor Corp.
    Inventors: Chien-Wei Hsin, Chung-Yao Chang
  • Patent number: 8913697
    Abstract: A wireless LAN communication device includes an amplifying circuit, an interference detection circuit, a false alarm counting circuit, and a control circuit. The amplifying circuit is configured to operably provide a gain to wireless signals. The interference detection circuit is configured to operably detect adjacent channel interference signals to generate a detection result. The false alarm counting circuit is configured to operably calculate a number of false alarms incurred by the adjacent channel interference signals. The control circuit is configured to operably configure the gain of the amplifying circuit according to the detection result and the number of false alarms.
    Type: Grant
    Filed: March 22, 2013
    Date of Patent: December 16, 2014
    Assignee: Realtek Semiconductor Corp.
    Inventors: Chien-Wei Hsin, Chung-Yao Chang
  • Publication number: 20140341263
    Abstract: A calibration method for calibrating a communication system includes: generating a test signal at a transmitter; configuring at least one calibration coefficient at the transmitter; configuring at least one calibration coefficient at the receiver; transmitting the test signal to a receiver via the calibration coefficient; performing a spectrum analysis upon the test signal received by the receiver to generate a spectrum analysis result; and adjusting the calibration coefficient according to the spectrum analysis result to calibrate the transmitter. In addition, a calibration method is also provided for calibrating a receiver of a communication system, and related calibration apparatuses are further provided.
    Type: Application
    Filed: May 15, 2014
    Publication date: November 20, 2014
    Applicant: Realtek Semiconductor Corp.
    Inventors: Chih-Yung Wu, Chung-Yao Chang
  • Patent number: 8862068
    Abstract: A wireless apparatus and an interference determination method thereof are provided. The wireless apparatus determines that the wireless apparatus operates in a first bandwidth mode, and counts a first clear channel assessment (CCA) number associated with a primary channel, a second CCA number associated with a secondary channel, an entire CCA number associated with either the primary channel or the secondary channel, and the false alarm number according to at least one received radio frequency (RF) signal. Afterwards, the wireless apparatus determines that the second CCA number exceeds the summation of the first CCA number and bias number to determine that it is in an interference state, and determines that the interference state belongs to either the first interference type or second interference type according to the radio of the entire CCA number to the FA number.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: October 14, 2014
    Assignee: Realtek Semiconductor Corporation
    Inventors: Chien-Wei Hsin, Chung-Yao Chang
  • Patent number: 8817842
    Abstract: A communication device is disclosed, having a transceiving circuit, a timer circuit, and a control circuit. The transceiving circuit is used to transceive frequency hopping signals according to at least part of good channels in a channel map. The timer circuit is used to calculate a timespan of one or more communication intervals in which the transceiving circuit transceives the frequency hopping signals. The control circuit is used to compare the timespan with a time threshold to determine whether signal transmission tests with one or more bad channels in the channel map should be performed to update the channel map.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: August 26, 2014
    Assignee: Realtek Semiconductor Corp.
    Inventors: Yan-Yu Chen, Chung-Yao Chang
  • Patent number: 8767803
    Abstract: A wireless communication circuit is disclosed including: a transceiver for transmitting and receiving signals; and a control circuit coupled with the transceiver for controlling a switching circuit to switch the transceiver to a first antenna set for a first time period and then to switch the transceiver to a second antenna set for a second time period in a test period. If a throughput statistic of the first antenna set with respect to the test period is greater than that of the second antenna set, the control circuit configures the switching circuit to switch the transceiver to the first antenna set after the test period.
    Type: Grant
    Filed: August 16, 2012
    Date of Patent: July 1, 2014
    Assignee: Realtek Semiconductor Corp.
    Inventors: Tsung-Hsuan Lee, Chung-Yao Chang, Der-Zheng Liu
  • Publication number: 20140169195
    Abstract: The present invention discloses a wireless transmission rate adjustment method for adjusting the wireless transmission rate of a wireless transmission device.
    Type: Application
    Filed: December 3, 2013
    Publication date: June 19, 2014
    Applicant: REALTEK SEMICONDUCTOR CORPORATION
    Inventors: Chien-Wei Hsin, Wei-Hsuan Chang, Chung-Yao Chang
  • Publication number: 20140064115
    Abstract: A bandwidth selection method includes capturing at least one first quality information corresponding to a first bandwidth, computing at least one first threshold value according to the at least one first quality information and at least one first weighting index, capturing at least one second quality information corresponding to a second bandwidth, comparing the first threshold value with the second quality information to obtain a first comparison result, and selecting one of the first bandwidth and the second bandwidth as a used bandwidth of a filter according to the first comparison result.
    Type: Application
    Filed: December 17, 2012
    Publication date: March 6, 2014
    Applicant: REALTEK SEMICONDUCTOR CORP.
    Inventors: Wei-Hsuan Chang, Chung-Yao Chang
  • Publication number: 20130316660
    Abstract: A wireless apparatus and an interference determination method thereof are provided. The wireless apparatus determines that the wireless apparatus operates in a first bandwidth mode, and counts a first clear channel assessment (CCA) number associated with a primary channel, a second CCA number associated with a secondary channel, an entire CCA number associated with either the primary channel or the secondary channel, and the false alarm number according to at least one received radio frequency (RF) signal. Afterwards, the wireless apparatus determines that the second CCA number exceeds the summation of the first CCA number and bias number to determine that it is in an interference state, and determines that the interference state belongs to either the first interference type or second interference type according to the radio of the entire CCA number to the FA number.
    Type: Application
    Filed: September 14, 2012
    Publication date: November 28, 2013
    Applicant: REALTEK SEMICONDUCTOR CORPORATION
    Inventors: Chien-Wei HSIN, Chung-Yao CHANG
  • Publication number: 20130308731
    Abstract: A wireless LAN communication device includes an amplifying circuit, an interference detection circuit, a false alarm counting circuit, and a control circuit. The amplifying circuit is configured to operably provide a gain to wireless signals. The interference detection circuit is configured to operably detect adjacent channel interference signals to generate a detection result. The false alarm counting circuit is configured to operably calculate a number of false alarms incurred by the adjacent channel interference signals. The control circuit is configured to operably configure the gain of the amplifying circuit according to the detection result and the number of false alarms.
    Type: Application
    Filed: March 22, 2013
    Publication date: November 21, 2013
    Applicant: Realtek Semiconductor Corp.
    Inventors: Chien-Wei HSIN, Chung-Yao CHANG
  • Publication number: 20130281144
    Abstract: A channel selection method includes steps of generating a plurality of test carriers on a plurality of different candidate channels, respectively; obtaining a plurality of channel quality information corresponding to the plurality of test carriers, respectively; generating a test result according to the plurality of channel quality information; and selecting a target channel from the plurality of candidate channels according to the test result.
    Type: Application
    Filed: January 10, 2013
    Publication date: October 24, 2013
    Applicant: Realtek Semiconductor Corp.
    Inventors: Wei-Hsuan Chang, Chung-Yao Chang