Patents by Inventor Changyou Xu

Changyou Xu 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: 8688873
    Abstract: Various embodiments of the present invention provide systems and methods for monitoring out of order data decoding. For example, a method for monitoring out of order data processing is provided that includes receiving a plurality of data sets that is associated with a plurality of identifiers with each of the plurality of identifiers indicates a respective one of the plurality of data sets; storing each of the plurality of identifiers in a FIFO memory in an order that the corresponding data sets of the plurality of data sets was received; processing the plurality of data sets such that at least one of the plurality of data sets is provided as an output data set; accessing the next available identifier from the FIFO memory; and asserting an out of order signal when the next available identifier is not the same as the identifier associated with the output data set.
    Type: Grant
    Filed: December 31, 2009
    Date of Patent: April 1, 2014
    Assignee: LSI Corporation
    Inventors: Changyou Xu, Shaohua Yang, Kapil Gaba
  • Patent number: 8683299
    Abstract: In one embodiment, a turbo equalizer has a channel detector that receives equalized samples and generates channel soft-output values. An LDPC decoder attempts to decode the channel soft-output values to recover an LDPC-encoded codeword. If the decoder converges on a trapping set, then an adjustment block selects one or more of the equalized samples based on one or more specified conditions and adjusts the selected equalized samples. Selection may be performed by identifying the locations of unsatisfied check nodes of the last local decoder iteration and selecting the equalized samples that correspond to bit nodes of the LDPC-encoded codeword that are connected to the unsatisfied check nodes. Adjustment of the equalized samples may be performed using any combination of scaling, offsetting, and saturation. Channel detection is then performed using the adjusted equalized samples to generate an updated set of channel soft-output values, which are subsequently decoded by the decoder.
    Type: Grant
    Filed: August 12, 2009
    Date of Patent: March 25, 2014
    Assignee: LSI Corporation
    Inventors: Kiran Gunnam, Shaohua Yang, Changyou Xu
  • Patent number: 8677209
    Abstract: In a communications system that demultiplexes user data words into multiple sub-words for encoding and decoding within different subword-processing paths, the minimum distance between bit errors in an extrinsic codeword can be increased by having corresponding subword encoders/decoders in the different subword-processing paths perform subword encoding/decoding with different encoder/decoder matrices.
    Type: Grant
    Filed: December 22, 2009
    Date of Patent: March 18, 2014
    Assignee: LSI Corporation
    Inventors: Kiran Gunnam, Yang Han, Shaohua Yang, Changyou Xu
  • Patent number: 8634152
    Abstract: Systems, methods, devices, circuits for data processing, and more particularly, and more particularly to data processing relying on efficiency improved data detection.
    Type: Grant
    Filed: October 15, 2012
    Date of Patent: January 21, 2014
    Assignee: LSI Corporation
    Inventors: Shaohua Yang, Changyou Xu
  • Patent number: 8631300
    Abstract: The present inventions are related to systems and methods for data processing, and more particularly to systems and methods for power governance in a data processing system.
    Type: Grant
    Filed: December 12, 2011
    Date of Patent: January 14, 2014
    Assignee: LSI Corporation
    Inventors: Yang Han, Shaohua Yang, Zhi Kai Chen, Lei Wang, Changyou Xu
  • Publication number: 20130339827
    Abstract: Various embodiments of the present inventions are related to adaptive calibration of NPFIR filters in a data detector. For example, an apparatus for calibrating a noise predictive filter is disclosed, including a data detector operable to generate detected values for data sectors and having an embedded noise predictive finite impulse response filter. The apparatus also includes a comparator operable to determine whether a quality metric for a current one of the data sectors meets a noise threshold. The apparatus also includes a filter calibration circuit operable to adapt a number of filter coefficients for the noise predictive finite impulse response filter based on the detected values for the data sectors, and to omit the detected values for the current one of the data sectors from adaptation for one of the filter coefficients if the quality metric for the current one of the data sectors does not meet the noise threshold.
    Type: Application
    Filed: June 15, 2012
    Publication date: December 19, 2013
    Inventors: Yang Han, Shaohua Yang, Fan Zhang, Zongwang Li, Changyou Xu
  • Patent number: 8607115
    Abstract: In one embodiment, an LDPC decoder has a controller and one or more check-node units (CNUs). Each CNU is selectively configurable to operate in (i) a first mode that updates check-node (i.e., R) messages without averaging and (ii) a second mode that that updates R messages using averaging. Initially, each CNU is configured in the first mode to generate non-averaged R messages, and the decoder attempts to recover an LDPC-encoded codeword using the non-averaged R messages. If the decoder is unable to recover the correct codeword, then (i) the controller selects the averaging mode, (ii) each CNU is configured to operate in the second mode to generate averaged R messages, and (iii) the decoder attempts to recover the correct codeword using the averaged R messages. Averaging the R messages may slow down the propagation of erroneous messages that lead the decoder to convergence on trapping sets.
    Type: Grant
    Filed: June 1, 2009
    Date of Patent: December 10, 2013
    Assignee: LSI Corporation
    Inventors: Kiran Gunnam, Shaohua Yang, Changyou Xu
  • Patent number: 8578253
    Abstract: Various embodiments of the present invention provide systems and methods for updating detector parameters in a data processing circuit. For example, a data processing circuit is disclosed that includes a first detector circuit, a second detector circuit, and a calibration circuit. The first detector circuit is operable to receive a first data set and to apply a data detection algorithm to the first data set, and the second detector circuit is operable to receive a second data set and to apply the data detection algorithm to the second data set. The calibration circuit is operable to calculate a data detection parameter based upon a third data set. The data detection parameter is used by the first detector circuit in applying the data detection algorithm to the first data set during a period that the data detection parameter is used by the second detector circuit in applying the data detection algorithm to the second data set.
    Type: Grant
    Filed: January 4, 2010
    Date of Patent: November 5, 2013
    Assignee: LSI Corporation
    Inventors: Shaohua Yang, Jonseung Park, Changyou Xu, Madhusudan Kalluri, Yuan Xing Lee, Kapil Gaba
  • Patent number: 8560929
    Abstract: Various embodiments of the present invention provide systems and methods for data processing. A data processing circuit is disclosed that includes: a data detector circuit, a first symbol constrained arrangement circuit, and a second symbol constrained arrangement circuit. The data detector circuit is operable to apply a data detection algorithm to a combination of a first input data set and a decoded data set to yield a detected output that includes a number of non-binary symbols. The first symbol constrained arrangement circuit is operable to receive the detected output and to re-arrange the detected output in accordance with a first arrangement algorithm to yield a re-arranged output. The bits for at least one non-binary symbol from the detected output are maintained together in the re-arranged output.
    Type: Grant
    Filed: June 24, 2011
    Date of Patent: October 15, 2013
    Assignee: LSI Corporation
    Inventors: Zongwang Li, Wu Chang, Chung-Li Wang, Changyou Xu, Shaohua Yang, Yang Han
  • Patent number: 8531320
    Abstract: Various embodiments of the present invention provide systems and methods for data processing. For example, a data processing system is disclosed that includes a data decoder circuit. The data decoder circuit is operable to: apply a decoding algorithm to a decoder input on a first decoder iteration to yield a first decoder output; compress an output derived from the first decoder output to yield a compressed decoder output; de-compress the compressed decoder output to yield a second decoder output; and apply the decoding algorithm to the second decoder output to yield a third decoder output.
    Type: Grant
    Filed: November 14, 2011
    Date of Patent: September 10, 2013
    Assignee: LSI Corporation
    Inventors: Zongwang Li, Chung-Li Yang, Shaohua Yang, Changyou Xu
  • Publication number: 20130212447
    Abstract: Various embodiments of the present invention provide systems and methods for decoding of non-binary LDPC codes. For example, a low density parity check data decoder is disclosed that includes a variable node processor operable to perform variable node updates based at least in part on check node to variable node message vectors, a check node processor operable to perform check node updates and to generate the check node to variable node message vectors, and a scheduler operable to cause the variable node processor to use check node to variable node message vectors from multiple decoding iterations when performing the variable node updates for a given decoding iteration.
    Type: Application
    Filed: February 9, 2012
    Publication date: August 15, 2013
    Inventors: Zongwang Li, Chung-Li Wang, Changyou Xu
  • Publication number: 20130198554
    Abstract: The present inventions are related to systems and methods for data processing, and more particularly to systems and methods for power governance in a data processing system.
    Type: Application
    Filed: February 1, 2012
    Publication date: August 1, 2013
    Inventors: Shaohua Yang, Changyou Xu, Fan Zhang
  • Patent number: 8499231
    Abstract: Various embodiments of the present invention provide systems and methods for data processing. As an example, a data processing circuit is disclosed that includes a data detecting circuit having: a first vector translation circuit, a second vector translation circuit, and a data detector core circuit. The data detecting circuit is operable to receive an input data set and at least one input vector in a first format. The at least one input vector corresponds to a portion of the input data set. The first vector translation circuit is operable to translate the at least one vector to a second format. The data detector core circuit is operable to apply a data detection algorithm to the input data set and the at least one vector in the second format to yield a detected output. The second vector translation circuit operable to translate a derivative of the detected output to the first format to yield an output vector.
    Type: Grant
    Filed: June 24, 2011
    Date of Patent: July 30, 2013
    Assignee: LSI Corporation
    Inventors: Zongwang Li, Wu Chang, Chung-Li Wang, Changyou Xu, Shaohua Yang, Yang Han
  • Publication number: 20130148232
    Abstract: Various embodiments of the present invention provide systems and methods for data processing. For example, a data processing system is disclosed that includes a combination data decoder circuit. The combination data decoder circuit includes: a non-binary data decoder circuit and a binary data decoder circuit.
    Type: Application
    Filed: December 12, 2011
    Publication date: June 13, 2013
    Inventors: Zongwang Li, Chung-Li Wang, Shaohua Yang, Changyou Xu, Lei Chen, Yang Han
  • Publication number: 20130151923
    Abstract: The present inventions are related to systems and methods for data processing, and more particularly to systems and methods for power governance in a data processing system.
    Type: Application
    Filed: December 12, 2011
    Publication date: June 13, 2013
    Inventors: Yang Han, Shaohua Yang, Zhi Kai Chen, Lei Wang, Changyou Xu
  • Patent number: 8464142
    Abstract: In one embodiment, an LDPC decoder has a controller and an extrinsic log-likelihood (LLR) value generator. The extrinsic LLR value generator is selectively configurable to operate in either (i) a non-averaging mode that updates extrinsic LLR values without averaging or (ii) an averaging mode that updates extrinsic LLR values using averaging. Initially, the extrinsic LLR value generator is configured to generate non-averaged extrinsic LLR values, and the decoder attempts to recover an LDPC-encoded codeword using the non-averaged extrinsic LLR values. If the decoder is unable to recover the correct codeword, then (i) the controller selects the averaging mode, (ii) the extrinsic LLR value generator is configured to generate average extrinsic LLR values, and (iii) the decoder attempts to recover the correct codeword using the average extrinsic LLR values. Averaging the extrinsic LLR values may slow down the propagation of erroneous messages that lead the decoder to convergence on trapping sets.
    Type: Grant
    Filed: April 23, 2010
    Date of Patent: June 11, 2013
    Assignee: LSI Corporation
    Inventors: Kiran Gunnam, Shaohua Yang, Changyou Xu
  • Patent number: 8446683
    Abstract: Various embodiments of the present invention provide systems and methods for selecting between pre-coding and non-pre-coding. As an example, a data processing circuit is disclosed that includes: a first data detector circuit, a second data detector circuit, a first comparator circuit, a second comparator circuit, and a pre-code selection circuit. The first data detector circuit is selectably configurable to operate in a pre-coded state, and operable to apply a data detection algorithm on a data input to yield a first detected output. The second data detector circuit operable to apply the data detection algorithm to the data input to yield a second detected output without compensating for pre-coding. The first comparator circuit operable to compare the first detected output against a known input to yield a first comparison value, and the second comparator circuit operable to compare the second detected output against the known input to yield a second comparison value.
    Type: Grant
    Filed: February 22, 2011
    Date of Patent: May 21, 2013
    Assignee: LSI Corporation
    Inventors: Changyou Xu, Shaohua Yang, Haitoa Xia, Kapil Gaba
  • Publication number: 20130120167
    Abstract: Various embodiments of the present invention provide systems and methods for data processing. For example, a data processing system is disclosed that includes a data decoder circuit. The data decoder circuit is operable to: apply a decoding algorithm to a decoder input on a first decoder iteration to yield a first decoder output; compress an output derived from the first decoder output to yield a compressed decoder output; de-compress the compressed decoder output to yield a second decoder output; and apply the decoding algorithm to the second decoder output to yield a third decoder output.
    Type: Application
    Filed: November 14, 2011
    Publication date: May 16, 2013
    Inventors: Zongwang Li, Chung-Li Yang, Shaohua Yang, Changyou Xu
  • Patent number: 8443267
    Abstract: Various embodiments of the present invention provide systems and methods for data processing. For example, a data processing system is disclosed that includes a processing loop circuit having a data detector and a soft decision decoder. The data detector provides a detected output, and the soft decision decoder applies a soft decoding algorithm to a derivative of the detected output to yield a soft decision output and a first hard decision output. The systems further include a queuing buffer and a hard decision decoder. The queuing buffer is operable to store the soft decision output, and the hard decision decoder accesses the soft decision output and applies a hard decoding algorithm to yield a second hard decision output. The data detector is operable to perform a data detection on a derivative of the soft decision output if the soft decision decoder and the hard decision decoder fail to converge.
    Type: Grant
    Filed: April 28, 2009
    Date of Patent: May 14, 2013
    Assignee: LSI Corporation
    Inventors: Hao Zhong, Shaohua Yang, Weijun Tan, Changyou Xu, Yuan Xing Lee
  • Publication number: 20130103731
    Abstract: Various embodiments of the present invention provide systems and methods for data processing. For example, a data processing system is disclosed that includes: a data detector circuit, a pseudo-random sequence generator circuit, a decoder circuit, and a pseudo-random sequence reconstitution circuit. The data detector circuit is operable to apply a data detection algorithm to a first data set to yield a detected output. The pseudo-random sequence generator circuit is operable to generate an interim data sequence and to generate a second data set based upon a combination of the detected output and the interim data sequence. The decoder circuit is operable to apply a data decode algorithm to a derivative of the second data set to yield a third data set.
    Type: Application
    Filed: October 24, 2011
    Publication date: April 25, 2013
    Inventors: Changyou Xu, Shaohua Yang, Kapil Gaba