Patents by Inventor Yung-Ha JI

Yung-Ha JI 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: 9215614
    Abstract: The disclosure is related to controlling an operation bandwidth for a femtocell based on femtocell interference to a macrocell in order to minimize femtocell interference. A femtocell base station may include a measurement unit, a transmitting unit, and a control unit. The measurement unit may be configured to measure an interference amount of a macrocell adjacent to the femtocell base station. The transmitting unit may be configured to transmit the measured interference amount to a system. The control unit may be configured to i) accept an allocated operation bandwidth by the system and ii) control transmission and reception of signals with the allocated operation bandwidth. The operation bandwidth may be adjustable by the system based on the measured interference amount.
    Type: Grant
    Filed: April 16, 2012
    Date of Patent: December 15, 2015
    Assignee: KT CORPORATION
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Publication number: 20150305036
    Abstract: A mobile communication system for providing carrier aggregation between digital units, and a method for processing a signal in the system are provided. The mobile communication system includes: a plurality of digital units connected to a core system and configured to process a radio digital signal; a blade server connected to at least two or more digital units and configured to perform resource allocation on signals processed by the connected digital units; and a plurality of radio units physically separated from the digital units, configured to convert and amplify digital signals received from the digital units, and transmit the same to a terminal, and configured to receive a signal transmitted from the terminal and transmit the received signal to the digital units. In the system, a mobile communication service is provided to the terminal by using carrier aggregation between radio units respectively connected to at least two or more digital units and using different frequencies.
    Type: Application
    Filed: September 2, 2013
    Publication date: October 22, 2015
    Applicant: KT CORPORATION
    Inventors: Ki-Ho LEE, Yong-Gyoo LEE, Yung-Ha JI
  • Publication number: 20150304881
    Abstract: Provided are a mobile communication system, a digital unit, and a method of establishing a joint transmission area in the system. When the digital unit determines that a terminal is located in a joint transmission area based on signal strength values received from two of radio units and transmission powers of the two radio units, the digital unit adjusts the joint transmission area depending on the load on the network including the two radio units belong in order to allow the two radio units to perform a joint transmission function to send at least one of the same signal and a spatiotemporally coded signal of the same data to the terminal.
    Type: Application
    Filed: September 2, 2013
    Publication date: October 22, 2015
    Applicant: KT CORPORATION
    Inventors: Ki-Ho LEE, Yong-Gyoo LEE, Yung-Ha JI
  • Publication number: 20150289278
    Abstract: A resource management apparatus for managing a plurality of base stations (BSs) includes a load information management unit configured to manage load information of the plurality of BSs, a neighbor BS list management unit configured to manage a neighbor BS list of each BS, and a resource allocation unit. The resource allocation unit is configured to vary quantity of resources allocated to a target BS from among the plurality of BSs based on load information of the target BS and at least one neighbor BS of the target BS, upon reception of a resource allocation request from the target BS.
    Type: Application
    Filed: July 26, 2013
    Publication date: October 8, 2015
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Publication number: 20150282164
    Abstract: The present disclosure relates to resource allocation method and apparatus. The resource allocation method includes monitoring resource information of a plurality of base stations including a first base station and a second base station, receiving a resource allocation request from a first terminal that is located in a boundary region and connected to the first base station, and checking whether a second terminal using a voice service is located in the boundary region. When the second terminal is located in the boundary region, resources are allocated to the first terminal based on resources allocated to the second terminal. The boundary region is an overlapped region of cells of the first base station and the second base station.
    Type: Application
    Filed: July 18, 2013
    Publication date: October 1, 2015
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Publication number: 20150282100
    Abstract: A signal processing system, a digital signal processing device (or a digital unit), and a method of controlling transmission power in the system are provided. The digital unit allocates relatively high transmission power to a terminal located in a boundary area of adjacent cells served by two radio units, is higher than transmission power for transmitting data to a terminal located at about a central area of each cell, rather than the boundary cell of adjacent cells.
    Type: Application
    Filed: September 2, 2013
    Publication date: October 1, 2015
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Patent number: 9055503
    Abstract: Described embodiments provide a method of effectively selecting a target cell to hand over user equipment from a LTE network to a non-LTE network when the user equipment requests a CS service. A LTE cell may determine a CS fallback hysteresis parameter in advance. The LTE cell may receive signal quality measurements of at least two candidate non-LTE cells from the user equipment. The LTE cell may select one target cell among the at least two candidate non-LTE cells based on the CS fallback hysteresis parameter and the received signal quality measurements of the at least two candidate non-LTE cells.
    Type: Grant
    Filed: August 1, 2012
    Date of Patent: June 9, 2015
    Assignee: KT CORPORATION
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Patent number: 9014146
    Abstract: Described embodiments provide a method and apparatus for redirecting user equipment from a current serving cell of a first network to a corresponding target cell of a second network in a heterogeneous overlay network environment. A current serving base station of the first network may receive signal quality measurements from user equipment coupled to the current serving cell of the first network. Based on the received signal quality measurements, the current serving base station may determine whether signal quality of the user equipment is lower than predetermined reference quality based on at least one of the received signal quality measurements. When the signal quality of the user equipment is lower than the predetermined reference quality, the current serving base station may redirect the user equipment from the current serving cell of the first network to the corresponding target cell of the second network.
    Type: Grant
    Filed: October 25, 2012
    Date of Patent: April 21, 2015
    Assignee: KT Corporation
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Patent number: 9008101
    Abstract: The disclosure is related to performing a packet scheduling in a wireless communication network. Quality of service (QoS) information associated with user equipment may be obtained in the wireless communication network. A channel status associated with the user equipment may be estimated in the wireless communication network. A scheduling interval may be determined based on the QoS information and the channel status.
    Type: Grant
    Filed: December 7, 2012
    Date of Patent: April 14, 2015
    Assignee: KT Corporation
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Publication number: 20150092685
    Abstract: A signal processing system and a signal processing method are provided.
    Type: Application
    Filed: October 31, 2012
    Publication date: April 2, 2015
    Applicant: KT Corporation
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Publication number: 20150087326
    Abstract: The disclosure is related to a method of adaptive call admission control in a base station. When a call access request is received from a user equipment determination may be made as to whether an available call admission capacity of the base station reaches a first limit. When the available call admission capacity of the base station reaches the first limit determination may be made as to whether the received call access request is for a preferred call. Then, determination may be made as to whether a reserved call admission capacity reaches a second limit when the received call access request is for the preferred call. When the reserved call admission capacity has not reached a second limit, access of the user equipment associated with the received call access request may be allowed.
    Type: Application
    Filed: December 1, 2014
    Publication date: March 26, 2015
    Inventors: Jae-Ho CHUNG, Wi-Sang RHO, Yung-Ha JI, Kyu-Jeong HAN
  • Patent number: 8964643
    Abstract: The disclosure is related to distributing a network load in overlay heterogeneous networks. A call connection request may receive from user equipment. A user preferred network may be identified based on predetermined network access priority information associated with the user equipment. Network redirection may be determined based on the user preferred network. Network redirection information may be created based on the determined network redirection.
    Type: Grant
    Filed: October 25, 2012
    Date of Patent: February 24, 2015
    Assignee: KT Corporation
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Patent number: 8929910
    Abstract: The disclosure is related to a method of adaptive call admission control in a base station. When a call access request is received from a user equipment determination may be made as to whether an available call admission capacity of the base station reaches a first limit. When the available call admission capacity of the base station reaches the first limit determination may be made as to whether the received call access request is for a preferred call. Then, determination may be made as to whether a reserved call admission capacity reaches a second limit when the received call access request is for the preferred call. When the reserved call admission capacity has not reached a second limit, access of the user equipment associated with the received call access request may be allowed.
    Type: Grant
    Filed: May 8, 2013
    Date of Patent: January 6, 2015
    Assignee: KT Corporation
    Inventors: Jae-Ho Chung, Wi-Sang Rho, Yung-Ha Ji, Kyu-Jeong Han
  • Publication number: 20150003426
    Abstract: A method and apparatus for scheduling in a wireless communication system configured for coordinated scheduling are disclosed. The scheduling apparatus sets a gain to be obtained when a terminal performs coordinated scheduling in a neighboring cell. The scheduling apparatus determines whether the terminal in the neighboring cell has moved between a first region where coordinated scheduling is not performed and a second region where coordinated scheduling is performed. Next, if it is determined that the terminal in the neighboring cell has moved between the first region where coordinated scheduling is not performed and the second region where coordinated scheduling is performed, the scheduling apparatus controls the radio unit in the neighboring cell to set an Modulation and Coding Scheme (MCS) level based on the gain and perform scheduling based on the MCS level.
    Type: Application
    Filed: November 2, 2012
    Publication date: January 1, 2015
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Publication number: 20150004983
    Abstract: Described embodiments provide an apparatus and method for selectively providing system information in a heterogeneous network environment including a first network overlaid on a second network. The apparatus may include a location determination unit, a mapping table, and a signal processor. The location determination unit may be configured to determine a first network base station in the first network. The mapping table may be configured to store information on at least one second network cell in a second network, which is spatially in a comparatively close distance to each first network base station in the first network. The signal processor may be configured to determine at least one second network cell spatially close to the determined first network base station based on the mapping table and to transmit system information of the at least one second network cell to the user equipment.
    Type: Application
    Filed: September 17, 2014
    Publication date: January 1, 2015
    Inventors: Ki-Ho LEE, Yong-Gyoo LEE, Yung-Ha JI
  • Publication number: 20140357320
    Abstract: A digital unit, a signal processing system, and a signal processing method are disclosed. The signal processing system includes a digital unit and a plurality of radio units. The digital unit is connected to a core system and configured to process radio digital signals. The plurality of radio units are physically isolated from the digital unit and configured to convert and amplify digital signals received from the digital unit, to transmit the amplified signals to a terminal based on a multi-antenna technology using two antennas, and to receive the signals from the terminal and to transmit the same to the digital unit based on the multi-antenna technology using two antennas, If a first cell is adjacent to a second cell and if the first cell and the second cell are configured to use the same reference signal, a radio unit of the first cell and a radio unit of the second cell use the same resource element to transmit the same data to a terminal located in a boundary region of the first and second cells.
    Type: Application
    Filed: November 6, 2012
    Publication date: December 4, 2014
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Publication number: 20140359740
    Abstract: A WiFi roaming management method and device which redirect an HTTP request of a mobile terminal from an AP to an AC even though the AC and the AP do not exist in the same subnet, which redirects a source IP address for an HTTP request, after transferring, to an IP address of the AC, and which smoothly support a wireless Internet service in a distributed processing system according to a web authentication of the AC in a WiFi roaming method is provided. A terminal session management function and a traffic control function are separated by a premium AC (Access Controller) and a premium AP (Access Point) interworked with a tunneling method according to a CAPWAP protocol.
    Type: Application
    Filed: October 19, 2011
    Publication date: December 4, 2014
    Applicant: KT Corporation
    Inventors: Joo Young Yoon, Kyu Jeong Han, Yung Ha Ji
  • Patent number: 8898783
    Abstract: A wireless access point and a method may be provided for detecting a malicious device in a network. The wireless access point may include a controller, a search unit, a message generation unit, and a determination unit. The controller may be configured to initiate a malicious device detection mode regularly at predefined intervals. The search unit may be configured to detect candidate devices broadcasting a signal with the first SSID from neighbor devices in an associated network. The message generation unit may be configured to generate a test message in the malicious device detection mode and transmit the test message to the candidate devices. The determination unit may be configured to determine a corresponding device in the candidate device as a malicious device when a test response message is not received from the corresponding device in response to the test message.
    Type: Grant
    Filed: May 21, 2012
    Date of Patent: November 25, 2014
    Assignee: KT Corporation
    Inventors: Jaeho Chung, Yung-Ha Ji, Joo-Young Yoon, Kyu-Jeong Han
  • Publication number: 20140341185
    Abstract: A WiFi roaming method and device which perform an authentication and accounting process once for multiple APs, thereby reducing the load of an authentication server (RADIUS) in a WiFi roaming method, which separates a terminal session management function and a traffic control function by a access controller and a access point interworked with a tunneling method according to a CAPWAP (Control and Provisioning of Wireless Access Points) protocol.
    Type: Application
    Filed: October 19, 2011
    Publication date: November 20, 2014
    Applicant: KT CORPORATION
    Inventors: Joo Young Yoon, Kyu Jeong Han, Yung Ha Ji
  • Publication number: 20140328224
    Abstract: Described embodiments provide a method for processing an uplink signal in a radio unit. A first uplink signal may be received directly from user equipment. The received uplink signal may be delayed using uplink delay information. A second uplink signal may be received indirectly from user equipment through at least one repeater connected to the radio unit. The delayed first uplink signal and the second uplink signal may be combined and transmitted to a digital unit.
    Type: Application
    Filed: July 16, 2014
    Publication date: November 6, 2014
    Inventors: Ki-Ho LEE, Yong-Gyoo LEE, Yung-Ha JI