Patents by Inventor Sung-Cheol Chang

Sung-Cheol 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).

  • APPARATUS AND METHOD FOR TRANSMITTING DISCOVERY SIGNAL
    Publication number: 20140071916
    Abstract: A device transmits a discovery signal including identification information of the device in an empty discovery slot among a plurality of discovery slots of a discovery interval. The discovery signal includes two orthogonal frequency division multiplexing (OFDM) symbols. One of the two orthogonal frequency division multiplexing (OFDM) symbols includes at least one tone. The identification information of the device is displayed by a position of a subcarrier corresponding to the at least one tone.
    Type: Application
    Filed: September 10, 2013
    Publication date: March 13, 2014
    Applicant: Electronics and Telecommunications Research Institute
    Inventors: Chanho YOON, Hyung Jin KIM, Seungkwon CHO, Sung Kyung KIM, Soojung JUNG, Sung Cheol CHANG
  • METHOD AND APPARATUS FOR TRANSMITTING SYNCHRONIZATION SIGNAL IN TALK-AROUND DIRECT COMMUNICATION NETWORK
    Publication number: 20140073372
    Abstract: A method and apparatus for transmitting a synchronization signal in a talk-around direct communication network is provided. The method includes: determining one of a plurality of second windows included in a first window as a synchronization reception window; selecting one of a plurality of synchronization slots included in the second windows as a first synchronization slot; transmitting a first synchronization signal through the first synchronization slot included in the second windows, excluding the synchronization reception window; detecting a second synchronization signal transmitted from other terminals using the first synchronization slot included in the synchronization reception window; and determining that a collision from amongst the synchronization signals has occurred based on the detection result.
    Type: Application
    Filed: September 12, 2013
    Publication date: March 13, 2014
    Applicant: Electronics and Telecommunications Research Institute
    Inventors: Hyun LEE, Mi Young YUN, Seok Ki KIM, Won-Ik KIM, Chul Sik YOON, Sung Cheol CHANG
  • METHOD OF TRANSMITTING AND RECEIVING DATA IN TALK-AROUND DIRECT COMMUNICATION NETWORK
    Publication number: 20140071917
    Abstract: A method in which a transmitting terminal included in an talk-around direct communication (TDC) network transmits data includes: determining a data frame for transmitting the data; requesting to reserve a data transmission segment included in the data frame through a transmission request segment included in the data frame; receiving a response signal transmitted in a transmission response segment included in the data frame; and analyzing the response signal and transmitting the data through the data transmission segment.
    Type: Application
    Filed: September 11, 2013
    Publication date: March 13, 2014
    Applicant: Electronics and Telecommunications Research Institute
    Inventors: Sung Kyung KIM, Soojung Jung, Seungkwon Cho, Hyung Jin Kim, Chanho Yoon, Sung Cheol Chang
  • Radio resource reallocating method for circuit mode
    Patent number: 8649334
    Abstract: The present invention relates to a radio resource reallocation method based on the circuit mode. In order to efficiently use the radio resource in the packet-based data transmission system, a circuit mode radio resource is reallocated based on a rearrangement information element and a rearrangement counter information element by using the circuit mode. Accordingly, an unused region of the discontinuous radio resource that can be generated by resource de-allocation and resource change can be eliminated, and a resource allocation mismatch that can be generated by a MAP receiving error can be solved.
    Type: Grant
    Filed: May 30, 2008
    Date of Patent: February 11, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Sung Kyung Kim, Sung Cheol Chang, Kwang Jae Lim, Chul Sik Yoon
  • METHOD FOR COMMUNICATION OF BASE STATION AND TERMINAL
    Publication number: 20140038580
    Abstract: A method of performing communication of a terminal includes the terminal transmitting state information thereof to a base station, and the terminal receiving a mode change request from the base station when the terminal is selected by the base station.
    Type: Application
    Filed: October 10, 2013
    Publication date: February 6, 2014
    Applicant: Electronics and Telecommunications Research Institute
    Inventors: Won-Ik KIM, Eunkyung Kim, Sung Kyung Kim, Sung Cheol Chang, Jae Sun Cha, Mi Young Yun, Hyun Lee, Chul Sik Yoon, Kwang Jae Lim
  • Method of transmitting control information and terminal thereof
    Patent number: 8644233
    Abstract: A terminal transmits control information to a base station by using a periodically allocated dedicated channel. In further detail, the terminal checks control information that needs to be transmitted, detects a priority of the checked control information, and selects control information to be transmitted to the base station based on the detected priority. The terminal forms a PDU by multiplexing the selected control information, and transmits the PDU to the base station.
    Type: Grant
    Filed: May 6, 2009
    Date of Patent: February 4, 2014
    Assignees: Samsung Electronics Co., Ltd., Electronics and Telecommunications Research Institute
    Inventors: Sung Cheol Chang, Kwang Jae Lim, Sung Kyung Kim, Seok Heon Cho, Chul Sik Yoon
  • METHOD AND APPARATUS FOR MANAGING RESOURCE
    Publication number: 20140016580
    Abstract: A method of managing a resource is provided by a base station. The base station allocates a resource to a terminal, and generates a downlink control channel including information of the allocated resource and a transmission time of a next downlink control channel. Further, the base station transmits the downlink control channel to the terminal.
    Type: Application
    Filed: July 9, 2013
    Publication date: January 16, 2014
    Inventors: Sung Kyung KIM, Sung Cheol CHANG, Chul Sik YOON, Mi Young YUN, Won-Ik KIM, Hyun LEE, Seokki KIM
  • METHOD OF DIRECT COMMUNICATION
    Publication number: 20140016531
    Abstract: Upon receiving a multicast packet from a base station, a forwarding terminal connected to the base station establishes a multicast connection with at least one direct communication terminal having a direct communication group identifier mapped to a multicast IP address of the multicast packet, and transmits the multicast packet to the at least one direct communication terminal, thereby providing multicast services to a direct communication terminal not connected to the base station.
    Type: Application
    Filed: July 9, 2013
    Publication date: January 16, 2014
    Inventors: Mi Young YUN, Chul Sik YOON, Hyun LEE, Seokki KIM, Won-Ik KIM, Sung Kyung KIM, Sung Cheol CHANG
  • SIGNALLING METHOD FOR DIRECT COMMUNICATION BETWEEN TERMINALS
    Publication number: 20140017991
    Abstract: A signaling method for a terminal that performs direct communication between terminals terminal is disclosed. A transmitting terminal transmits a link establishment request message for establishing a link to a receiving terminal, and the receiving terminal transmits a link establishment response message responding to this message to the transmitting terminal. The link establishment request message includes a field indicating a flow to use if the receiving terminal acquires a token.
    Type: Application
    Filed: July 9, 2013
    Publication date: January 16, 2014
    Inventors: Sung Cheol CHANG, Mi Young YUN, Seokki KIM, Won-Ik KIM, Hyun LEE, Sung Kyung KIM, Chul Sik YOON
  • METHOD AND APPARATUS FOR TRANSMITTING FRAMES IN TALK-AROUND DIRECT COMMUNICATION
    Publication number: 20140016619
    Abstract: A permutated channel structure based on a block structure in talk-around direct communication is provided. A dedicated subchannel interferes with only one adjacent dedicated subchannel, even with a large synchronization error, by permutating the dedicated subchannels by cyclic shifts, whereby diversity gain can be maintained and interference between adjacent channels can be minimized.
    Type: Application
    Filed: July 9, 2013
    Publication date: January 16, 2014
    Inventors: Seokki KIM, Sung Cheol Chang, Mi Young Yun, Won Ik Kim, Hyun Lee, Sung Kyung Kim, Chul Sik Yoon
  • Terminal, method for handover thereof and supporting method for handover of base station
    Patent number: 8630649
    Abstract: A handover method of a terminal in a macro cell including a plurality of femto cells includes scanning information on a femto base station for managing a femto cell that is near the terminal from among the plurality of femto cells, and reporting information on the femto base station to a macro base station for managing the macro cell.
    Type: Grant
    Filed: October 29, 2009
    Date of Patent: January 14, 2014
    Assignees: Samsung Electronics Co., Ltd., Electronics and Telecommunications Research Institute
    Inventors: Sung-Geun Jin, Sung Cheol Chang, Won-Ik Kim, Chul Sik Yoon
  • MOBILE RELAY STATION AND HANDOVER METHOD THEREOF
    Publication number: 20130294330
    Abstract: A mobile relay station (RS) and a handover method thereof are provided. When it is determined that a mobile RS performs handover from a superordinate base station (BS) to a target BS, information indicating admission of handover is received from the superordinate BS. The mobile RS transmits a service unavailability section to a subordinate terminal, whereby the subordinate terminal is prevented from performing handover to a different BS or a different RS.
    Type: Application
    Filed: May 1, 2013
    Publication date: November 7, 2013
    Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Won-Ik KIM, Sung Kyung KIM, Seokki KIM, Mi Young YUN, Hyun LEE, Chul Sik YOON, Sung Cheol CHANG
  • MULTIMODE APPARATUS AND COMMUNICATON METHOD THEREOF
    Publication number: 20130286819
    Abstract: A multimode apparatus and a communication method thereof are disclosed. If the multimode apparatus is chosen to serve as a relay station due to a base station having a backhaul link problem, it sets up a first relay link with a first base station. Upon receiving a request for releasing the first relay link from the first base station even though the backhaul link is not restored, the multimode apparatus sets up a second relay link with a second base station, or configures and operates a standalone network or an independent network.
    Type: Application
    Filed: March 6, 2013
    Publication date: October 31, 2013
    Inventors: Eunkyung Kim, Won-Ik Kim, Sung Kyung Kim, Sung Cheol Chang, Seokki Kim, Mi Young Yun, Hyun Lee, Chul Sik Yoon, Kwang Jae Lim
  • Method and apparatus for controlling power for uplink
    Patent number: 8559360
    Abstract: A method and apparatus for controlling power for uplink are provided. When a base station is moving or unable to communicate with others, at least one interference amount is estimated for a neighboring base station based on a path gain between a terminal and the neighboring base station and a transmission power of each encoding packet size and transmission format included in a candidate group related to scheduling transmission power parameters. A target interference amount is determined based on an interference amount control value and an initial target interference amount according to a processing load of a serving base station, and one interference amount is selected from estimated interference amounts based on the target interference amount. The terminal determines the transmission power based on an encoding packet size and a transmission format corresponding to the selected interference amount.
    Type: Grant
    Filed: December 10, 2010
    Date of Patent: October 15, 2013
    Assignees: Samsung Electronics Co., Ltd., Electronics and Telecommunications Research Institute
    Inventors: Hyun-Jae Kim, Sung Cheol Chang, Sung Kyung Kim, Won-Ik Kim, Chul Sik Yoon
  • Method for providing service of femtocell, and transmitter and receiver for the same
    Patent number: 8548468
    Abstract: A service method of a femtocell for simultaneously providing a plurality of femto services to a plurality of mobile stations, and a transmitter and receiver for the same. When a femto advanced base station supports a plurality of femtocell subscription types, and it simultaneously provides data services with different qualities to mobile stations having subscribed to different femtocells. The femtocell subscription type supported by the femto advanced base station is advertised to the mobile station through an identifier at a PHY level or an identifier at a MAC level. A CSG-closed femtocell provides a high-quality data service to limited subscribers, a CSG-open femtocell provides a relatively low quality data service to limited subscribers, and an OSG femtocell provides the lowest quality data service to all mobile stations irrespectively of subscription states.
    Type: Grant
    Filed: August 26, 2011
    Date of Patent: October 1, 2013
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Sung-Geun Jin, Sung Cheol Chang, Won-Ik Kim, Chul Sik Yoon
  • Method and apparatus for controlling retransmission
    Patent number: 8522103
    Abstract: A method of controlling retransmission in a transmitter, the method provides transmitting a medium access control (MAC) management message to a receiver by hybrid automatic retransmit request (HARQ) and initiating retransmission of the MAC management message when an HARQ process is terminated with an unsuccessful transmission of the MAC management message before an expiration of a retransmission timer for the MAC management message.
    Type: Grant
    Filed: May 6, 2009
    Date of Patent: August 27, 2013
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Sung Kyung Kim, Kwang Jae Lim, Sung Cheol Chang, Chul Sik Yoon
  • MOBILE STATION, BASE STATION, AND RELAY STATION FOR A WIRELESS ACCESS SYSTEM
    Publication number: 20130208584
    Abstract: Protocol structure of a mobile station, base station or relay station in a wireless access system is provided. The protocol structure includes a first function block configured to perform radio resource control and management as a MAC layer and to reside on a control plane, and a second function block configured to perform medium access control as the MAC layer and to reside on the control plane and a data plane. The first function block includes various function blocks for supporting high reliability.
    Type: Application
    Filed: October 28, 2011
    Publication date: August 15, 2013
    Inventors: Eunkyung Kim, Sung Cheol Chang, Sung Kyung Kim, Hyun Lee, Chul Sik Yoon
  • Method for allocating authorization key identifier for wireless portable internet system
    Patent number: 8479270
    Abstract: A method and authentication apparatus for sharing information for identifying an Authorization Key (AK) with a Base Station (BS) in a subscriber station are provided. The method includes, in the subscriber station, sharing a root key with the BS by performing an authentication with the BS, sharing an AK derived from the root key with the BS, sharing an AK sequence number of the AK with the BS, and sharing an AK Identifier (AKID) of the AK with the BS. The AK sequence number is generated by a sequence number of the root key. The AKID is generated by a parameter including the AK, the AK sequence number, a Medium Access Control (MAC) address of the subscriber station, and a BS Identifier (BSID) of the BS.
    Type: Grant
    Filed: June 7, 2011
    Date of Patent: July 2, 2013
    Assignees: Samsung Electronics Co., Ltd., Electronics and Telecommunications Research Institute, KT Corporation, SK Telecom Co., Ltd., Hanaro Telecom, Inc.
    Inventors: Seok-Heon Cho, Sung-Cheol Chang, Chul-Sik Yoon
  • GROUP COMMUNICATION METHOD AND APPARATUS
    Publication number: 20130130736
    Abstract: A group communication method of a terminal is provided. The terminal establishes a group call connection with a first base station belonging to a group call zone, and receives group call data from the first base station. When moving to the coverage area of a second base station belonging to the group call zone, the terminal receives group call data from the second base station.
    Type: Application
    Filed: September 30, 2011
    Publication date: May 23, 2013
    Applicant: Electronics and Telecommunications Research Institute
    Inventors: Sung Kyung Kim, Sung Cheol Chang, Eunkyung Kim, Hyun Lee, Chul Sik Yoon
  • MULTICAST MANAGEMENT METHOD AND APPARATUS
    Publication number: 20130121236
    Abstract: A multicast management method of a base station is provided. The base station generates a CRC for a message including resource allocation information of a multicast group including a plurality of terminals, and masks the CRC by a CRC mask. The base station adds the masked CRC to the message, and then transmits the message to which the masked CRC is added to the multicast group.
    Type: Application
    Filed: July 25, 2011
    Publication date: May 16, 2013
    Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Eunkyung Kim, Sung Cheol Chang, Sung Kyung Kim, Hyun Lee, Chul Sik Yoon