Patents by Inventor Joseph C. Chan

Joseph C. Chan 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: 8989311
    Abstract: Wireless receiver circuits and methods include algorithms for switching between a least-squares/minimum mean-square error method of channel estimation known as the CE algorithm, and a continuous plot method of channel estimation known as the CPCE algorithm based upon channel characteristics to improve reception of wireless communications in different reception conditions. In an embodiment, the CPCE algorithm may be selected by a processor for use in channel estimation when a calculated number of candidate paths is less than or equal to a first threshold value, a calculated power ratio of the L strongest paths to the total of all paths is greater than or equal to a second threshold value, and the maximum Automatic Gain Control variation is greater than or equal to a third threshold value. Threshold values may be based on field testing, and set to values at which the CE or CPCE algorithm exhibits better performance.
    Type: Grant
    Filed: September 22, 2010
    Date of Patent: March 24, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: Jeremy M. Stein, James E. Beckman, Joseph C. Chan, Michael Leviant
  • Patent number: 8554251
    Abstract: An apparatus and method for processing signals are disclosed. The apparatus may include a transceiver configured to receive a first paging signal during a first cycle, a memory, and a processor configured to store the received first paging signal in the memory, to switch the transceiver to an off state after the first paging signal is stored in the memory, and to process the stored first paging signal while the transceiver is in the off state.
    Type: Grant
    Filed: June 29, 2009
    Date of Patent: October 8, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Supratik Bhattacharjee, Joseph C. Chan, Brian C. Banister, Shivratna G. Srinivasan
  • Patent number: 8527993
    Abstract: Techniques are provided which may be implemented in various methods and/or apparatuses that to provide a tasking system buffer interface capability to interface with a plurality of shared processes/engines.
    Type: Grant
    Filed: October 1, 2010
    Date of Patent: September 3, 2013
    Assignee: Qualcomm Incorporated
    Inventors: Raheel Khan, Joseph C. Chan, Ron Shalev, Naveed U. Zaman
  • Publication number: 20120069937
    Abstract: Wireless receiver circuits and methods include algorithms for switching between a least-squares/minimum mean-square error method of channel estimation known as the CE algorithm, and a continuous plot method of channel estimation known as the CPCE algorithm based upon channel characteristics to improve reception of wireless communications in different reception conditions. In an embodiment, the CPCE algorithm may be selected by a processor for use in channel estimation when a calculated number of candidate paths is less than or equal to a first threshold value, a calculated power ratio of the L strongest paths to the total of all paths is greater than or equal to a second threshold value, and the maximum Automatic Gain Control variation is greater than or equal to a third threshold value. Threshold values may be based on field testing, and set to values at which the CE or CPCE algorithm exhibits better performance.
    Type: Application
    Filed: September 22, 2010
    Publication date: March 22, 2012
    Applicant: QULACOMM Incorporated
    Inventors: JEREMY M. STEIN, JAMES E. BECKMAN, JOSEPH C. CHAN, MICHAEL LEVIANT
  • Publication number: 20110296415
    Abstract: Techniques are provided which may be implemented in various methods and/or apparatuses that to provide a tasking system buffer interface capability to interface with a plurality of shared processes/engines.
    Type: Application
    Filed: October 1, 2010
    Publication date: December 1, 2011
    Applicant: QUALCOMM Incorporated
    Inventors: Raheel Khan, Joseph C. Chan, Ron Shalev, Naveed U. Zaman
  • Publication number: 20100331019
    Abstract: An apparatus and method for processing signals are disclosed. The apparatus may include a transceiver configured to receive a first paging signal during a first cycle, a memory, and a processor configured to store the received first paging signal in the memory, to switch the transceiver to an off state after the first paging signal is stored in the memory, and to process the stored first paging signal while the transceiver is in the off state.
    Type: Application
    Filed: June 29, 2009
    Publication date: December 30, 2010
    Inventors: Supratik Bhattacharjee, Joseph C. Chan, Brian C. Banister, Shivratna G. Srinivasan
  • Patent number: 7293216
    Abstract: A bit error position is estimated. The estimation method includes generating data indicative of a substantial number of bit error locations in data frames. The generation of the data includes re-encoding decoded bit stream, mapping the bit stream to a first set of symbols, and determining a soft decision distance between a second set of symbols received through a data transmission channel and the first set of symbols. The generated data is then used to estimate the bit error locations. The estimation process includes capturing metric data for each bit in the data frame and obtaining derivative of the metric data. The derivative may be filtered for further processing. Error position estimation criteria may then be applied to estimate the bit error positions.
    Type: Grant
    Filed: August 6, 2004
    Date of Patent: November 6, 2007
    Assignees: Sony Corporation, Sony Electronics Inc.
    Inventors: Robert L. Dorney, Joseph C. Chan
  • Patent number: 7039117
    Abstract: A method for concealing errors in texture partition of a video packet is described. The method includes determining a particular macroblock within the texture partition where error is detected, concealing the error starting at the particular macroblock, and evaluating image smoothness of concealed macroblocks. The concealing and evaluating are repeated with one more macroblock added prior to the previous particular macroblock. The concealing and evaluating are repeated until all macroblocks in the texture partition have been concealed. A set of macroblocks, including a combination of decoded and concealed macroblocks, that produces best image smoothness is then selected to replace the corrupted texture partition.
    Type: Grant
    Filed: August 16, 2001
    Date of Patent: May 2, 2006
    Assignees: Sony Corporation, Sony Electronics Inc.
    Inventor: Joseph C. Chan
  • Patent number: 6937573
    Abstract: The present invention provides several methods and apparatuses for varying the size of a radiolink protocol (RLP) packet based on channel condition estimation. According to one aspect, a channel condition metric is generated to indicate a channel condition. The channel condition metric is processed to determine the optimal packet-size for the channel condition. An optimal RLP packet-size that corresponds to the processed channel condition metric is chosen. All the optimal RLP packets that are control type are equipped with CRC bits and sent to the requester. Sending an optimal RLP packet helps maximize system throughput and adding CRC bits to the control type RLP packets prevents the RLP packet from getting rejected due to bit errors.
    Type: Grant
    Filed: January 10, 2001
    Date of Patent: August 30, 2005
    Assignees: Sony Corporation, Sony Electronics Inc.
    Inventors: Joseph C. Chan, Chi-ping Nee, Chinh Tran
  • Patent number: 6865227
    Abstract: A method for concealing errors in video data is disclosed. The method includes decoding a first set of motion vectors and estimating a second set of remaining motion vectors in the corrupted video packet. A motion compensated temporal replacement of texture data is performed using the first and second sets of motion vectors. The image smoothness of the texture data is then performed. The decoding, estimating, performing temporal replacement, and evaluating are repeated with one less motion vector in the first set and one more motion vector in the second set. The repeating is done until there is no more motion vector left in the first set. Sets of motion vectors that produce a best image smoothness measure of the texture data are selected from the first and second sets.
    Type: Grant
    Filed: July 10, 2001
    Date of Patent: March 8, 2005
    Assignees: Sony Corporation, Sony Electronics Inc.
    Inventor: Joseph C. Chan
  • Patent number: 6803864
    Abstract: A method and apparatus for entering characters with a reduced number of key presses. The sequence of one or more previously entered characters is used to select a character assignment matrix. The order of characters in the assignment matrix is determined by the probability that the letter will be the next in the sequence, with more likely characters being presented first. Repeated key presses are used to access characters with lower probability.
    Type: Grant
    Filed: May 18, 2001
    Date of Patent: October 12, 2004
    Assignees: Sony Corporation, Sony Electronics Inc.
    Inventor: Joseph C. Chan
  • Patent number: 6789225
    Abstract: A bit error position is estimated. The estimation method includes generating data indicative of a substantial number of bit error locations in data frames. The generation of the data includes re-encoding decoded bit stream, mapping the bit stream to a first set of symbols, and determining a soft decision distance between a second set of symbols received through a data transmission channel and the first set of symbols. The generated data is then used to estimate the bit error locations. The estimation process includes capturing metric data for each bit in the data frame and obtaining derivative of the metric data. The derivative may be filtered for further processing. Error position estimation criteria may then be applied to estimate the bit error positions.
    Type: Grant
    Filed: July 12, 2001
    Date of Patent: September 7, 2004
    Assignees: Sony Corporation, Sony Electronics Inc.
    Inventors: Robert L. Dorney, Joseph C. Chan
  • Publication number: 20030072368
    Abstract: A method and system for selectively protecting motion information of multimedia data. The multimedia data is initially examined to determine whether the motion information of the current multimedia data unit is lost or corrupted. The multimedia data is then examined to determine whether the motion information is important enough to adversely affect reliable prediction of that information if that the motion information of the current multimedia data unit is lost or corrupted. The motion information is selectively protected if the motion information is determined to be important enough.
    Type: Application
    Filed: October 15, 2001
    Publication date: April 17, 2003
    Inventors: Joseph C. Chan, Koji Kimura
  • Publication number: 20030035487
    Abstract: A method for concealing errors in texture partition of a video packet is described. The method includes determining a particular macroblock within the texture partition where error is detected, concealing the error starting at the particular macroblock, and evaluating image smoothness of concealed macroblocks. The concealing and evaluating are repeated with one more macroblock added prior to the previous particular macroblock. The concealing and evaluating are repeated until all macroblocks in the texture partition have been concealed. A set of macroblocks, including a combination of decoded and concealed macroblocks, that produces best image smoothness is then selected to replace the corrupted texture partition.
    Type: Application
    Filed: August 16, 2001
    Publication date: February 20, 2003
    Applicant: Sony Corporation and Sony Electronic Inc.
    Inventor: Joseph C. Chan
  • Publication number: 20030012280
    Abstract: A method for concealing errors in video data is disclosed. The method includes decoding a first set of motion vectors and estimating a second set of remaining motion vectors in the corrupted video packet. A motion compensated temporal replacement of texture data is performed using the first and second sets of motion vectors. The image smoothness of the texture data is then performed. The decoding, estimating, performing temporal replacement, and evaluating are repeated with one less motion vector in the first set and one more motion vector in the second set. The repeating is done until there is no more motion vector left in the first set. Sets of motion vectors that produce a best image smoothness measure of the texture data are selected from the first and second sets.
    Type: Application
    Filed: July 10, 2001
    Publication date: January 16, 2003
    Inventor: Joseph C. Chan
  • Publication number: 20030014710
    Abstract: A bit error position is estimated. The estimation method includes generating data indicative of a substantial number of bit error locations in data frames. The generation of the data includes re-encoding decoded bit stream, mapping the bit stream to a first set of symbols, and determining a soft decision distance between a second set of symbols received through a data transmission channel and the first set of symbols. The generated data is then used to estimate the bit error locations. The estimation process includes capturing metric data for each bit in the data frame and obtaining derivative of the metric data. The derivative may be filtered for further processing. Error position estimation criteria may then be applied to estimate the bit error positions.
    Type: Application
    Filed: July 12, 2001
    Publication date: January 16, 2003
    Inventors: Robert L. Dorney, Joseph C. Chan
  • Publication number: 20020180621
    Abstract: A method and apparatus for entering characters with a reduced number of key presses. The sequence of one or more previously entered characters is used to select a character assignment matrix. The order of characters in the assignment matrix is determined by the probability that the letter will be the next in the sequence, with more likely characters being presented first. Repeated key presses are used to access characters with lower probability.
    Type: Application
    Filed: May 18, 2001
    Publication date: December 5, 2002
    Inventor: Joseph C. Chan
  • Publication number: 20020089935
    Abstract: The present invention provides several methods and apparatuses for varying the size of a radiolink protocol (RLP) packet based on channel condition estimation. According to one aspect, a channel condition metric is generated to indicate a channel condition. The channel condition metric is processed to determine the optimal packet-size for the channel condition. An optimal RLP packet-size that corresponds to the processed channel condition metric is chosen. All the optimal RLP packets that are control type are equipped with CRC bits and sent to the requester. Sending an optimal RLP packet helps maximize system throughput and adding CRC bits to the control type RLP packets prevents the RLP packet from getting rejected due to bit errors.
    Type: Application
    Filed: January 10, 2001
    Publication date: July 11, 2002
    Inventors: Joseph C. Chan, Chi-ping Nee, Chinh Tran