Patents by Inventor Kapseok Chang

Kapseok 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: 20180159708
    Abstract: Disclosed is a technique related to a method and apparatus for generating a preamble and a data frame for wireless communication, and to a synchronization estimation method using the preamble. According to the technique, a method for generating a frame for wireless communication is disclosed, wherein the method comprises: a step of generating a modified sequence using a first base sequence for synchronization estimation; and a step of allocating the first base sequence and the modified sequence to the frequency domain of a first timeslot to generate a preamble. The modified sequence includes a complex conjugated sequence of the first base sequence or a sequence having a code different from that of the first base sequence.
    Type: Application
    Filed: January 15, 2018
    Publication date: June 7, 2018
    Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Kapseok Chang, Wooyong Lee, Hyun-Kyu Chung
  • Patent number: 9973326
    Abstract: Provided are an apparatus and method for transmitting/receiving a signal. The method for transmitting/receiving a signal includes reducing a quantization error in a baseband (BB) analog area with respect to a reception signal, and performing self-interference cancellation (SIC) on a first output signal output from a BB analog circuit unit in a digital area.
    Type: Grant
    Filed: November 17, 2015
    Date of Patent: May 15, 2018
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Kapseok Chang, Seon-Ae Kim, Hyung Sik Ju
  • Patent number: 9974056
    Abstract: When a transmitter transmits a first Timing Offset Indication iDentifier (TOID) of a plurality of TOIDs representing timing offset of a frame, the transmitter determines a first codeword corresponding to the first TOID of a plurality of codewords representing a subcarrier. The transmitter allocates a busy tone to a first subcarrier that the first codeword represents. The transmitter transmits the busy tone.
    Type: Grant
    Filed: May 6, 2015
    Date of Patent: May 15, 2018
    Assignee: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Kapseok Chang, Byung-Jae Kwak
  • Patent number: 9906390
    Abstract: Disclosed is a technique related to a method and apparatus for generating a preamble and a data frame for wireless communication, and to a synchronization estimation method using the preamble. According to the technique, a method for generating a frame for wireless communication is disclosed, wherein the method comprises: a step of generating a modified sequence using a first base sequence for synchronization estimation; and a step of allocating the first base sequence and the modified sequence to the frequency domain of a first timeslot to generate a preamble. The modified sequence includes a complex conjugated sequence of the first base sequence or a sequence having a code different from that of the first base sequence.
    Type: Grant
    Filed: August 23, 2010
    Date of Patent: February 27, 2018
    Assignee: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Kapseok Chang, Wooyong Lee, Hyun-Kyu Chung
  • Patent number: 9893871
    Abstract: Disclosed is an in-band full duplex transceiver. The in-band full duplex transceiver may include a transmitter, a hybrid transformer, and an impedance matching unit. The hybrid transformer may include a first end connected to an antenna, may output a transmitting signal to the antenna, and may output a received signal provided through the antenna to the receiver. The impedance matching unit may include balance networks connected to a second end of the hybrid transformer and matching impedance of the antenna.
    Type: Grant
    Filed: October 30, 2015
    Date of Patent: February 13, 2018
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Kapseok Chang, Seon-Ae Kim, Hyung Sik Ju, Youngsik Kim
  • Publication number: 20180041976
    Abstract: A method and an apparatus for secondary synchronization in the Internet of things. The receiving apparatus extracts a frequency domain sample by applying channel estimation to a time domain sample of the secondary synchronization signal. Further, the receiving apparatus estimates a physical cell ID (PCI) and 80 ms frame timing (FT) based on decorrelation between a frequency domain standard signal of the secondary synchronization signal and the frequency domain sample.
    Type: Application
    Filed: August 7, 2017
    Publication date: February 8, 2018
    Inventors: Kapseok CHANG, Moon-Sik LEE
  • Publication number: 20180041978
    Abstract: A method and an apparatus for primary synchronization in the Internet of things. A receiver samples a primary synchronization signal into a digital signal to generate a first sampling signal and down sample a first sampling signal into a second sampling signal. The receiver estimates a first sample timing offset (STO) and a first frequency offset (FO) using the first sampling signal and the second sampling signal.
    Type: Application
    Filed: August 7, 2017
    Publication date: February 8, 2018
    Inventors: Kapseok CHANG, Moon-Sik LEE
  • Patent number: 9860864
    Abstract: Disclosed herein are a method of performing synchronization in a distributed wireless communication system, and a terminal supporting the same. A distributed wireless communication system includes a plurality of networks. Time resources of each of a plurality of networks are divided into a synchronization slot, a discovery slot, a peering slot, and a data slot. A first terminal belonging to a first network determines whether a synchronization signal is received from a terminal belonging to a second network in the data slot of the first network. The first terminal detects whether it has met the second network that is out of synchronization with the first network if the synchronization signal is determined to have been received.
    Type: Grant
    Filed: March 12, 2015
    Date of Patent: January 2, 2018
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Byung-Jae Kwak, Kapseok Chang, June-Koo Rhee, Junhyuk Kim
  • Publication number: 20170367147
    Abstract: A method and apparatus for setting up a relay link to transfer a data frame using a relay in a wireless communication system are provided. The relay link setup method of a source STA in a wireless communication system may include receiving capability information of at least one relay supporting station included in the wireless communication system from an access point (AP) or a personal basic service set (PBSS) central point (PCP), selecting one of the at least one relay supporting station as a relay station, using beam forming information among the source station, a destination station, and the at least one relay supporting station and the capability information, transferring a relay link setup request frame to the destination station, and receiving a relay link setup response frame that includes information on a relay link setup result from the destination station. The relay link setup request frame and the relay link setup response frame may pass through the relay station.
    Type: Application
    Filed: August 14, 2017
    Publication date: December 21, 2017
    Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Hyoung-Jin KWON, Sung-Geun JIN, Kapseok CHANG, Woo-Yong LEE
  • Publication number: 20170295050
    Abstract: A method and an apparatus for generating a synchronization signal in the Internet of things. In the method for generating a synchronization signal, subcarrier mapping may be performed by exchanging a signal allocated to an upper subcarrier group and a signal allocated to a lower subcarrier group among all subcarriers allocated for the synchronization signal with each other, in an in-band operation mode or a guard band operation mode of the Internet of things.
    Type: Application
    Filed: April 6, 2017
    Publication date: October 12, 2017
    Inventors: Kapseok CHANG, Moon-Sik LEE, Ohyun JO
  • Patent number: 9736886
    Abstract: A method for setting up a relay link to transfer a data frame using a relay in a wireless communication system. The relay link setup method of a source in the system may include receiving capability information of at least one relay supporting station included in the system from an access point or a personal basic service set central point, selecting one of the at least one relay supporting station as a relay station, using beam forming information among the source station, a destination station, and the at least one relay supporting station and the capability information, transferring a relay link setup request frame to the destination station, and receiving a relay link setup response frame that includes information on a relay link setup result from the destination station. The relay link setup request frame and the relay link setup response frame may pass through the relay station.
    Type: Grant
    Filed: February 18, 2015
    Date of Patent: August 15, 2017
    Assignee: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Hyoung-Jin Kwon, Sung-Geun Jin, Kapseok Chang, Woo-Yong Lee
  • Patent number: 9699747
    Abstract: Disclosed is a synchronization method in a distributed wireless communication system and a terminal supporting the same. In a synchronization method, a terminal splits a synchronization period into a plurality of backoff slots and randomly selects a backoff counter using the contention window. Furthermore, the terminal checks whether a channel is idle during at least one of the plurality of backoff slots and changes the backoff counter based on a result of the check.
    Type: Grant
    Filed: September 11, 2015
    Date of Patent: July 4, 2017
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Byung-Jae Kwak, Kapseok Chang, June-Koo Rhee, Junhyuk Kim, Kyounghye Kim
  • Publication number: 20170181152
    Abstract: When a plurality of terminals share the same resources in a wireless communication system, and when control information such as acknowledgement/negative acknowledgement (ACK/NAK) information or scheduling information is transmitted, a method of efficiently performing code division multiplexing (CDM) is required to distinguish the plurality of terminals. In particular, it is necessary to develop a method by which a code sequence of CDM can be selected and used according to each cell condition. Provided is a method of forming a signal in a wireless communication system in which a plurality of terminals commonly share frequency and time resources. The method includes the operations of receiving condition information in a cell; selecting one of a plurality of time domain orthogonal sequences having different lengths, according to the condition information; and allocating the selected time domain orthogonal sequence to a control signal symbol block.
    Type: Application
    Filed: March 7, 2017
    Publication date: June 22, 2017
    Inventors: Young-Jo KO, Hyeong-Geun PARK, Il-Gyu Kim, Kapseok CHANG, Hyoseok Yi, Young-Hoon Kim, Seung-Chan Bang
  • Publication number: 20170156143
    Abstract: A first terminal generates a first scheduling request signal including information about first data resources for data transmission when the first terminal tries to reserve the first data resources. The first terminal generates a first scheduling request indication signal providing notification that the first scheduling request signal is to be transmitted. The first terminal transmits the first scheduling request indication signal through a first request subslot included in a first scheduling request resource before transmitting the first scheduling request signal. The first terminal transmits the first scheduling request signal through a second request subslot included in the first scheduling request resource.
    Type: Application
    Filed: May 5, 2015
    Publication date: June 1, 2017
    Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTIT UTE
    Inventors: Kapseok CHANG, Byung-Jae KWAK
  • Patent number: 9602233
    Abstract: When a plurality of terminals share the same resources in a wireless communication system, and when control information such as acknowledgement/negative acknowledgement (ACK/NAK) information or scheduling information is transmitted, a method of efficiently performing code division multiplexing (CDM) is required to distinguish the plurality of terminals. In particular, it is necessary to develop a method by which a code sequence of CDM can be selected and used according to each cell condition. Provided is a method of forming a signal in a wireless communication system in which a plurality of terminals commonly share frequency and time resources. The method includes the operations of receiving condition information in a cell; selecting one of a plurality of time domain orthogonal sequences having different lengths, according to the condition information; and allocating the selected time domain orthogonal sequence to a control signal symbol block.
    Type: Grant
    Filed: January 31, 2013
    Date of Patent: March 21, 2017
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Young-Jo Ko, Hyeong-Geun Park, Il-Gyu Kim, Kapseok Chang, Hyoseok Yi, Young-Hoon Kim, Seung-Chan Bag
  • Publication number: 20170026922
    Abstract: A method of searching a cell in a mobile station of a communication system in which a plurality of cells are grouped into a plurality of cell groups, each cell group including at least two cells, includes: detecting a primary synchronization signal and a secondary synchronization signal from a received signal; and identifying a cell based on a combination of the primary synchronization signal and the secondary synchronization signal. The secondary synchronization signal is related to the cell group to which the mobile station belongs and the primary synchronization signal is related to the cell to which the mobile station belongs within the cell group.
    Type: Application
    Filed: October 6, 2016
    Publication date: January 26, 2017
    Inventors: Il Gyu KIM, Hyeong Geun PARK, Young Jo KO, Kapseok CHANG, Hyo Seok YI, Young Hoon KIM, Seung Chan BANG
  • Publication number: 20170012762
    Abstract: A method and an apparatus for tuning an FIR filter in an in-band full duplex transceiver. The method for tuning an FIR filter includes: converting an input signal of the FIR filter into a first signal that is a baseband signal; converting a signal obtained by subtracting an output signal of the FIR filter from the self-transmitted interference signal into a second signal that is the baseband signal; and calculating attenuation of the FIR filter using the first signal and the second signal.
    Type: Application
    Filed: June 21, 2016
    Publication date: January 12, 2017
    Inventors: Kapseok CHANG, Hyung Sik JU
  • Publication number: 20160380799
    Abstract: A method and an apparatus for tuning an FIR filter in an in-band full duplex transceiver. The method for tuning an FIR filter may include: setting attenuation of the FIR filter to be a first value and then estimating input information of the FIR filter; estimating a delta response using the estimated input information of the FIR filter; and updating the attenuation of the FIR filter to a second value using the estimated delta response.
    Type: Application
    Filed: June 21, 2016
    Publication date: December 29, 2016
    Inventors: Kapseok CHANG, Hyung Sik JU
  • Publication number: 20160373234
    Abstract: Disclosed herein is an in-band full duplex transceiver, including: a multi polarized antenna including a plurality of polarized transmitting/receiving units transmitting/receiving different polarizations; and a plurality of transmitting/receiving modules each connected with the plurality of polarized transmitting/receiving units, receiving received signals through the plurality of polarized transmitting/receiving units, and transmitting transmitted signals through the plurality of polarized transmitting/receiving units, in which each of the transmitting/receiving modules may include: an analog circuit unit including a finite impulse response filter that converts an analog received signal received through the corresponding polarized transmitting/receiving unit into a digital received signal, converts a digital transmitted signal into an analog transmitted signal, and uses the analog transmitted signal to cancel self-interference from the analog received signal; and a distributor transmitting the analog receive
    Type: Application
    Filed: June 22, 2016
    Publication date: December 22, 2016
    Inventors: Hyung Sik JU, Kapseok CHANG
  • Patent number: 9497723
    Abstract: Disclosed is a method for adjusting a transmission time point of at least one second terminal in a wireless network by a first terminal. In the method for adjusting a transmission time point of a terminal, a transmission time point of the second terminal is set, a first frame including information regarding the transmission time point is transmitted to the second terminal, a first response frame transmitted according to the transmission time point from the second terminal is received, and the transmission time point is adjusted according to an arrival time of the first response frame.
    Type: Grant
    Filed: February 3, 2016
    Date of Patent: November 15, 2016
    Assignee: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Sung-Geun Jin, Kapseok Chang, Hyoung Jin Kwon, Woo Yong Lee, Hyun Kyu Chung