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: 10205572
    Abstract: A signal processing system and a signal processing method are provided.
    Type: Grant
    Filed: October 31, 2012
    Date of Patent: February 12, 2019
    Assignee: KT CORPORATION
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Patent number: 10182359
    Abstract: A method and apparatus for testing signal reception sensitivity of a wireless access point are provided. The apparatus includes a receiver which is configured to receive a test start request signal, a transmission power level change request signal and a test packet retransmission request signal from a neighboring access point apparatus; a test signal generator which is configured to generate a test packet signal to be transmitted to the neighboring access point apparatus; a transmission power level adjuster which is configured to adjust a transmission power level of the test packet signal; a transmitter which is configured to transmit the test packet signal to the neighboring access point apparatus with a power having a level adjusted by the transmission power level adjuster; and a test executor which is configured to execute a test program having a predetermined sequence for testing a signal reception sensitivity of the neighboring access point apparatus.
    Type: Grant
    Filed: October 17, 2011
    Date of Patent: January 15, 2019
    Assignee: KT Corporation
    Inventors: Jae Ho Chung, Wi Sang Rho, Yung Ha Ji, Kyu Jeong Han
  • Patent number: 10098072
    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, which 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: Grant
    Filed: September 2, 2013
    Date of Patent: October 9, 2018
    Assignee: KT CORPORATION
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Patent number: 9893848
    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: Grant
    Filed: September 2, 2013
    Date of Patent: February 13, 2018
    Assignee: KT CORPORATION
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Patent number: 9877222
    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: Grant
    Filed: September 2, 2013
    Date of Patent: January 23, 2018
    Assignee: KT CORPORATION
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Patent number: 9807762
    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: Grant
    Filed: July 18, 2013
    Date of Patent: October 31, 2017
    Assignee: KT CORPORATION
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Patent number: 9705657
    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: Grant
    Filed: November 2, 2012
    Date of Patent: July 11, 2017
    Assignee: KT CORPORATION
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Patent number: 9699695
    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: Grant
    Filed: September 17, 2014
    Date of Patent: July 4, 2017
    Assignee: KT CORPORATION
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Patent number: 9686722
    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: Grant
    Filed: October 19, 2011
    Date of Patent: June 20, 2017
    Assignee: KT Corporation
    Inventors: Joo Young Yoon, Kyu Jeong Han, Yung Ha Ji
  • Patent number: 9655126
    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: Grant
    Filed: July 26, 2013
    Date of Patent: May 16, 2017
    Assignee: KT CORPORATION
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Patent number: 9654970
    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: Grant
    Filed: October 19, 2011
    Date of Patent: May 16, 2017
    Assignee: KT Corporation
    Inventors: Joo Young Yoon, Kyu Jeong Han, Yung Ha Ji
  • Patent number: 9571184
    Abstract: A signal processing system and method are disclosed. The signal processing system includes a digital unit connected to a core system and a plurality of radio units physically isolated from the digital unit. The digital unit is configured to process radio digital signals. The plurality of radio units are configured to convert and amplify digital signals 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.
    Type: Grant
    Filed: November 6, 2012
    Date of Patent: February 14, 2017
    Assignee: KT CORPORATION
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Patent number: 9565606
    Abstract: Described embodiments provide controlling signal transmission in a plurality of radio units. The plurality of radio units may be coupled to a digital unit. The digital unit may be spatially separated from the plurality of radio units. Signal quality measurements may be received from multiple radio units when a user equipment is located within an overlapping service area of the multiple radio units. Determination may be made as to whether to simultaneously use at least two of the multiple radio units to transmit a data signal to the user equipment based on the received signal quality measurements. At least two of the multiple radio units may be controlled to transmit a same data signal to the user equipment using a same channel based on the determination result.
    Type: Grant
    Filed: August 16, 2012
    Date of Patent: February 7, 2017
    Assignee: KT CORPORATION
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Patent number: 9485737
    Abstract: Described embodiments provide a method for controlling radio units to transmit a signal to user equipment wherein each one of the radio units includes at least two antennas associated with a different transmission pattern. The method may include determining whether user equipment is located at an overlapping cell area of a first cell and a second cell and controlling a first radio unit in the first cell to transmit a signal to the user equipment using a first resource block and controlling a second radio unit in the second cell to transmit a reference signal associated with the first resource block with a second transmission power when the user equipment is determined as being located in the overlapping cell area. The second transmission power may be lower than a first transmission power of the first radio unit in the first cell for transmitting a reference signal using the first resource block.
    Type: Grant
    Filed: December 22, 2012
    Date of Patent: November 1, 2016
    Assignee: KT CORPORATION
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Patent number: 9467878
    Abstract: A method and an apparatus for testing a throughout of a wireless access point apparatus are provided. The apparatus includes a receiver which is configured to receive a test start request signal and a test packet transmission condition change request signal, a test signal generator which is configured to generate a test packet signal; a transmission condition adjuster configured to adjust the transmission condition of the test packet signal; a transmitter configured to transmit the test packet signal to the neighboring access point apparatus under the transmission condition, which is adjusted by the transmission condition adjuster; and a test executor configured to execute a test having a predetermined sequence so as to execute a throughput test for the neighboring access point apparatus with regards to receiving the test packet signal.
    Type: Grant
    Filed: October 19, 2011
    Date of Patent: October 11, 2016
    Assignee: KT Corporation
    Inventors: Jae Ho Chung, Sung Sang You, Jae Seon Jang, Yung Ha Ji
  • Patent number: 9432875
    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: December 1, 2014
    Date of Patent: August 30, 2016
    Assignee: KT CORPORATION
    Inventors: Jae-Ho Chung, Wi-Sang Rho, Yung-Ha Ji, Kyu-Jeong Han
  • Patent number: 9369194
    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: Grant
    Filed: July 16, 2014
    Date of Patent: June 14, 2016
    Assignee: KT CORPORATION
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Patent number: 9357505
    Abstract: Described embodiments provide a digital unit for controlling a plurality of radio units to transmit a signal to user equipment. The digital unit may determine whether user equipment is located at an overlapping service area of a first radio unit and a second radio unit and control the first radio unit to transmit a signal to the user equipment using the first antenna and control the second radio unit to transmit the same signal to the user equipment using the second antenna when the user equipment is located in the overlapping service area. A transmission pattern of the first antenna of the first radio unit may be different from a transmission pattern of the second antenna of the second radio unit.
    Type: Grant
    Filed: December 21, 2012
    Date of Patent: May 31, 2016
    Assignee: KT CORPORATION
    Inventors: Ki-Ho Lee, Yong-Gyoo Lee, Yung-Ha Ji
  • Patent number: 9271243
    Abstract: The device for controlling a wireless access point comprises: a grouping unit which groups wireless access points which use the same channel, by using channel use information received from the wireless access points; a map generator which computes each received signal strength value of the grouped wireless access points and each output strength value of the grouped wireless access points; an extractor which extracts a wireless access point having the highest received signal strength value among the grouped wireless access points, if interference occurs between said grouped wireless access points; and an optimal output strength value-calculator which computes a corrected output strength value by using the received signal strength value of the extracted wireless access point, a threshold value of predetermined received signal strength, and a currently used output strength value between said grouped wireless access points.
    Type: Grant
    Filed: October 19, 2011
    Date of Patent: February 23, 2016
    Assignee: KT Corporation
    Inventors: Byung Wan Yoon, Jae Ho Chung, Joo Young Yoon, Kyu Jeong Han, Yung Ha Ji
  • Patent number: 9231688
    Abstract: An apparatus for wireless relaying comprises: a transmission unit for generating a wireless signal; an amplification unit for amplifying and outputting the wireless signal; a conversion unit for converting the wireless signal into a digital signal; and an adjustment unit for adjusting the amplification ratio of the amplifying unit so that the difference between an output level value of the digital signal and a predetermined target power is lower than a predetermined numerical value.
    Type: Grant
    Filed: October 19, 2011
    Date of Patent: January 5, 2016
    Assignee: KT Corporation
    Inventors: Jae Ho Chung, Byung Wan Yoon, Yung Ha Ji, Kyu Jeong Han