Patents by Inventor Yuan-Shuo Chang

Yuan-Shuo 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: 8982993
    Abstract: A method for compensating mismatches of an in-phase signal and a quadrature signal of a transmitter/receiver is provided. The method includes: receiving a plurality of test signals to generate two groups of factors, respectively, where each group of factors is applied to two multipliers utilized for compensating a gain mismatch and a phase mismatch of the in-phase signal and the quadrature signal of the transmitter/receiver; then calculating a delay mismatch of the in-phase signal and the quadrature signal according to the two groups of factors.
    Type: Grant
    Filed: September 26, 2014
    Date of Patent: March 17, 2015
    Assignee: Realtek Semiconductor Corp.
    Inventors: Yuan-Shuo Chang, Hong-Ta Hsu
  • Publication number: 20150054585
    Abstract: A pre-distortion method includes: receiving an input data; and obtaining a pre-distortion output by inputting the input data into a pre-distortion function, wherein the pre-distortion function is determined according to a following power amplifier; and multiplying a reciprocal of a pre-distortion ratio of the output of the power amplifier to the input data by the output of the power amplifier. A pre-distortion apparatus includes a receiver, a pre-distortion unit and a gain compensating unit. The receiver is utilized for receiving an input data. The pre-distortion unit is utilized for obtaining a pre-distortion output by inputting the input data into a pre-distortion function, wherein the pre-distortion function is determined according to a following power amplifier. The gain compensating unit is utilized for multiplying a reciprocal of a pre-distortion ratio of the output of the power amplifier to the input data by the output of the power amplifier.
    Type: Application
    Filed: August 12, 2014
    Publication date: February 26, 2015
    Inventor: Yuan-Shuo Chang
  • Publication number: 20150015328
    Abstract: A pre-distortion method includes: receiving an input data; and obtaining a pre-distorted output by inputting the input data into a pre-distortion function, wherein the pre-distortion function is determined according to a power amplifier. A pre-distortion apparatus includes a receiver and a pre-distortion unit. The receiver is utilized for receiving an input data. The pre-distortion unit is utilized for obtaining a pre-distorted output by inputting the input data into a pre-distortion function, wherein the pre-distortion function is determined according to a following power amplifier. A non-transitory machine readable medium stores a program code executed for performing steps of the proposed pre-distortion method.
    Type: Application
    Filed: June 30, 2014
    Publication date: January 15, 2015
    Inventor: Yuan-Shuo Chang
  • Publication number: 20150010109
    Abstract: A method for compensating mismatches of an in-phase signal and a quadrature signal of a transmitter/receiver is provided. The method includes: receiving a plurality of test signals to generate two groups of factors, respectively, where each group of factors is applied to two multipliers utilized for compensating a gain mismatch and a phase mismatch of the in-phase signal and the quadrature signal of the transmitter/receiver; then calculating a delay mismatch of the in-phase signal and the quadrature signal according to the two groups of factors.
    Type: Application
    Filed: September 26, 2014
    Publication date: January 8, 2015
    Inventors: Yuan-Shuo Chang, Hong-Ta Hsu
  • Patent number: 8879677
    Abstract: A method for compensating mismatches of an in-phase signal and a quadrature signal of a transmitter/receiver is provided. The method includes: receiving a plurality of test signals to generate two groups of factors, respectively, where each group of factors is applied to two multipliers utilized for compensating a gain mismatch and a phase mismatch of the in-phase signal and the quadrature signal of the transmitter/receiver; then calculating a delay mismatch of the in-phase signal and the quadrature signal according to the two groups of factors.
    Type: Grant
    Filed: February 6, 2013
    Date of Patent: November 4, 2014
    Assignee: Realtek Semiconductor Corp.
    Inventors: Yuan-Shuo Chang, Hong-Ta Hsu
  • Publication number: 20140307765
    Abstract: A method for determining a default gain of a wireless transmission system is provided. The wireless transmission system includes a signal transmission path and a signal feedback path coupled to the signal transmission path. The signal transmission path includes a power amplification circuit and a gain stage having a plurality of transmission gains. The method includes the following step: setting a gain of the gain stage as a specific transmission gain of the transmission gains; transmitting a plurality of test signals through the signal transmission path in sequence to generate a plurality of amplified test signals, wherein at least a portion of powers of the test signals correspond to the transmission gains, respectively; receiving the amplified test signals through the signal feedback path in sequence, and accordingly obtaining corresponding signal gains; and determining a default gain of the gain stage according to the signal gains.
    Type: Application
    Filed: April 15, 2014
    Publication date: October 16, 2014
    Applicant: Realtek Semiconductor Corp.
    Inventors: Yuan-Shuo Chang, Chien-Yu Chen
  • Publication number: 20140300418
    Abstract: An auto gain adjusting device and method is disclosed. The auto gain adjusting device comprises a predistorter, a gain unit, a power amplifier, a receiving unit and a calculation unit. The predistorter generates a plurality of test signals in a calibration mode, wherein the powers between a current test signal and a previous test signal includes a first difference value. The gain unit provides a substantially constant gain value to the current test signal and the previous test signal to generate a current amplified test signal and a previous amplified test signal. The power amplifier amplifies the current amplified test signal and the previous amplified test signal to generate a first transmitting signal and a second transmitting signal. The receiving unit converts the first transmitting signal and the second transmitting signal into a first baseband signal and a second baseband signal respectively.
    Type: Application
    Filed: April 8, 2014
    Publication date: October 9, 2014
    Applicant: Realtek Semiconductor Corp.
    Inventor: YUAN-SHUO CHANG
  • Patent number: 8831550
    Abstract: Filter coefficients are generated by testing a wireless communication system using single-tone signals. While using the filter coefficients in a filter module, signal imbalance caused by a local oscillator or analog elements in a wireless communication system can be eliminated, so as to prevent the wireless communication system from being affected by the noises.
    Type: Grant
    Filed: July 8, 2013
    Date of Patent: September 9, 2014
    Assignee: Realtek Semiconductor Corp.
    Inventors: Yuan-Shuo Chang, Wen-Shan Wang
  • Publication number: 20140016690
    Abstract: Multiplier coefficients are updated according to minimal power value of mixed signals in a wireless communication system. While using updated multiplier parameters, signal imbalance caused by a local oscillator or mismatch between analog elements of the wireless communication system can be reduced, so that the wireless communication system can be immune from noises.
    Type: Application
    Filed: July 10, 2013
    Publication date: January 16, 2014
    Inventor: Yuan-Shuo Chang
  • Publication number: 20140018029
    Abstract: Filter coefficients are generated by testing a wireless communication system using single-tone signals. While using the filter coefficients in a filter module, signal imbalance caused by a local oscillator or analog elements in a wireless communication system can be eliminated, so as to prevent the wireless communication system from being affected by the noises.
    Type: Application
    Filed: July 8, 2013
    Publication date: January 16, 2014
    Inventors: Yuan-Shuo Chang, Wen-Shan Wang
  • Patent number: 8417193
    Abstract: The present invention provides a transmitting device and a method for determining a target predistortion setting value. The transmitting device comprises: a setting value control unit, a predistortion unit, a transmitting circuit, a receiving circuit, and a determining unit. The present invention can predistort signals before a power amplifier in a transmitting device by a method of determining a target predistortion setting value (i.e. an optimal predistortion setting value) from a plurality of candidate predistortion setting values. In this way, signals outputted by the power amplifier in the transmitting device can be adjusted to an optimal state, so as to solve the distortion problem of the outputted signals of the power amplifier.
    Type: Grant
    Filed: June 7, 2010
    Date of Patent: April 9, 2013
    Assignee: Realtek Semiconductor Corp.
    Inventor: Yuan-Shuo Chang
  • Publication number: 20120230451
    Abstract: A direct current (DC) offset estimation device includes a determining circuit and an estimation circuit. The determining circuit is arranged for comparing a plurality of bits of an access code in a packet with a first predetermined value, respectively, and accordingly generating a determining result. The estimation circuit is coupled to the determining circuit, for estimating a DC offset according to the determining result.
    Type: Application
    Filed: March 1, 2012
    Publication date: September 13, 2012
    Inventor: Yuan-Shuo Chang
  • Patent number: 8107573
    Abstract: An embodiment of the proposed invention is primarily applied to compensate the BLW in communication systems using THPs in their transmitters, especially suitable for the 10GBase-T Ethernet application. The present apparatus includes an additional decision device (slicer) used to generate DC offset information (error signal) and an extra modulus unit after our BLW compensator to reconvert compensated symbols to correct 16-PAM signals. In addition, the estimated error signals in our method are generated from the difference between the input of the BLW compensator and the output of the decision device. These error signals are then weighted to alleviate the impact of erroneous DC offset information on the performance of the BLW compensator. Therefore, a more direct and accurate DC offset information can be derived to improve the inaccurate BLW estimation in previous works.
    Type: Grant
    Filed: October 5, 2007
    Date of Patent: January 31, 2012
    Assignee: Realtek Semiconductor Corp.
    Inventor: Yuan-Shuo Chang
  • Publication number: 20100311351
    Abstract: The present invention provides a transmitting device and a method for determining a target predistortion setting value. The transmitting device comprises: a setting value control unit, a predistortion unit, a transmitting circuit, a receiving circuit, and a determining unit. The present invention can predistort signals before a power amplifier in a transmitting device by a method of determining a target predistortion setting value (i.e. an optimal predistortion setting value) from a plurality of candidate predistortion setting values. In this way, signals outputted by the power amplifier in the transmitting device can be adjusted to an optimal state, so as to solve the distortion problem of the outputted signals of the power amplifier.
    Type: Application
    Filed: June 7, 2010
    Publication date: December 9, 2010
    Inventor: Yuan-Shuo Chang
  • Publication number: 20100311360
    Abstract: A transmitter includes a predistortion calculation unit, a transmitting circuit, a receiving circuit, an adjusting unit and a parameter generating and storing unit. The predistortion calculation unit is utilized for pre-distorting an input signal to generate a predistorted input signal according to a specific predistortion parameter. The transmitting circuit is utilized for processing the predistorted input signal to generate an output signal. The receiving circuit is utilized for receiving the output signal to generate a received signal. The adjusting unit is utilized for adjusting the received signal to generate an adjusted signal, where the adjusted signal is substantially equal to the input signal. The parameter generating and storing unit is utilized for generating the specific predistortion parameter, and updating at least one stored predistortion parameter according to the input signal and the adjusted signal.
    Type: Application
    Filed: June 7, 2010
    Publication date: December 9, 2010
    Inventors: Fong-Ching Huang, Yuan-Shuo Chang
  • Publication number: 20080212715
    Abstract: An embodiment of the proposed invention is primarily applied to compensate the BLW in communication systems using THPs in their transmitters, especially suitable for the 10GBase-T Ethernet application. The present apparatus includes an additional decision device (slicer) used to generate DC offset information (error signal) and an extra modulus unit after our BLW compensator to reconvert compensated symbols to correct 16-PAM signals. In addition, the estimated error signals in our method are generated from the difference between the input of the BLW compensator and the output of the decision device. These error signals are then weighted to alleviate the impact of erroneous DC offset information on the performance of the BLW compensator. Therefore, a more direct and accurate DC offset information can be derived to improve the inaccurate BLW estimation in previous works.
    Type: Application
    Filed: October 5, 2007
    Publication date: September 4, 2008
    Inventor: Yuan-Shuo Chang
  • Publication number: 20070121718
    Abstract: A novel time-domain equalizer (TEQ) is provided for the receiver of a Discrete Multi-tone (DMT) system to shorten the length of the effective channel impulse response. The TEQ is based on a variant of the conventional decision-feedback equalizer (DFE) structure along with a training method for the TEQ settings. By using this DFE-based TEQ for DMT systems, the data symbols transmitted through the effective shortened channel would be more reliable.
    Type: Application
    Filed: January 29, 2007
    Publication date: May 31, 2007
    Inventors: Chin-Liang WANG, Yuan-Shuo Chang
  • Publication number: 20060034363
    Abstract: A novel structure for the TEQ in a DMT system receiver to shorten the length of the effective channel impulse response is provided. A time-domain equalizer, based on the decision-feedback filter structure, along with a training method is disclosed. In accordance with the DFE-based TEQ in the DMT system, the data symbols that transmitted through the effective shortened channel would be more reliable.
    Type: Application
    Filed: October 18, 2005
    Publication date: February 16, 2006
    Inventors: Chin-Liang Wang, Yuan-Shuo Chang, Chih-Ming Hsu
  • Patent number: 6704367
    Abstract: A discrete loading algorithm maximizes data rate or system performance margin for discrete multitone (DMT) transmission. A preliminary bit assignment for each subchannel is first obtained by optimizing a DMT system with an available bandwidth. The subchannels that receive negative bit assignments are then excluded for further optimization until all the bit assignments are positive. The bit assignment of each subchannel is rounded and a corresponding rounding error is calculated. If the total bit number of the bit assignments are greater than the available bandwidth, the bit assignment of the subchannel having the least rounding error is decreased by one bit. If the total bit number of the bit assignments are smaller than the available bandwidth, the bit assignment of the subchannel having the largest rounding error is increased by one bit.
    Type: Grant
    Filed: July 26, 2000
    Date of Patent: March 9, 2004
    Assignee: Proscend Communications Inc.
    Inventors: Chin-Liang Wang, Yuan-Shuo Chang
  • Publication number: 20030227967
    Abstract: A novel structure for the TEQ in a DMT system receiver to shorten the length of the effective channel impulse response is provided. A time-domain equalizer, based on the decision-feedback filter structure, along with a training method is disclosed. In accordance with the DFE-based TEQ in the DMT system, the data symbols that transmitted through the effective shortened channel would be more reliable.
    Type: Application
    Filed: June 6, 2002
    Publication date: December 11, 2003
    Inventors: Chin-Liang Wang, Yuan-Shuo Chang, Chih-Ming Hsu