Patents by Inventor Joo Heo

Joo Heo 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: 8116780
    Abstract: Provided are a dynamic resource allocation method based on frequency reuse partitioning for an Orthogonal Frequency Division Multiple Access (OFDMA) system, and a frame transmission method therefor. The dynamic resource allocation method includes: a) dividing a coverage into cells based on frequency reuse partitioning; b) selecting a candidate user to receive a channel allocated thereto based on the ratio; c) acquiring distance information for the candidate user; and d) checking whether the candidate user is in an inner or outer cell area based on the distance information. If the candidate user is in the inner cell area, a subchannel group among subchannel groups having a Frequency Reuse Factor (FRF) lower than a threshold value is selected and subcarriers of the selected subchannel group is allocated. If the candidate user is in the outer cell area, a subchannel group among subchannel groups having a FRF higher than the threshold value is selected.
    Type: Grant
    Filed: August 17, 2006
    Date of Patent: February 14, 2012
    Assignees: Electronics and Telecommunications Research Institute, Inha-Industry Partnership Institute
    Inventors: Hee-Soo Lee, Jae-Young Ahn, Kyung-Hi Chang, Joo Heo, In-Suk Cha
  • Publication number: 20090316635
    Abstract: Provided are a dynamic channel/power allocation method for an FRP-based OFDMA system and a frame/slot structure. capable of supporting the dynamic channel/power allocation method. In the FRP-based OFDMA system, each of cells has an inner cell, an outer cell and a plurality of sectors and performs data communication with a plurality of MSs therein through one or more orthogonal subchannel groups. In the dynamic channel/power allocation method, a BS receives a feedback channel condition from an MS provided with a service of the BS and allocates a subchannel group with a high SINR to each MS in consideration of the fairness and the distance information of each MS. Power is allocated to each MS on the basis of the conditions of a channel allocated to each MS, thereby obtaining a multi-user diversity gain.
    Type: Application
    Filed: May 19, 2009
    Publication date: December 24, 2009
    Inventors: Kyung Hi Chang, In Suk Cha, Joo Heo
  • Publication number: 20090196362
    Abstract: Provided are a transmission method and apparatus for allocating a subchannel and forming a stationary beam to maximize transmission efficiency in an OFDMA based wireless communication system. The method includes determining the subchannel for the equipment of each user based on the channel state of the equipment of each user, determining a beam index for the equipment of each user, based on location information and direction of arrival information of the equipment of each user, generating an OFDM symbol by mapping a modulation symbol corresponding to the equipment of each user to the determined subchannel, and transmitting the generated OFDM symbol to a wireless space by forming a beam following the determined beam index. Using the method, the equipment of each user can be allocated with an advantageous subchannel, can remove an interference signal at low cost, and can increase total throughput of an OFDMA system downlink.
    Type: Application
    Filed: September 28, 2006
    Publication date: August 6, 2009
    Inventors: Myung-Sun Song, Sung-Hyun Hwang, Gwang-Zeen Ko, Kyung-Hi Chang, Sung-Ho Park, Sang-Jun Ko, Joo Heo, Jung-Ju Kim
  • Publication number: 20080232320
    Abstract: Provided are a dynamic resource allocation method based on frequency reuse partitioning for an Orthogonal Frequency Division Multiple Access (OFDMA) system, and a frame transmission method therefor. The dynamic resource allocation method includes: a) dividing a coverage into cells based on frequency reuse partitioning; b) selecting a candidate user to receive a channel allocated thereto based on the ratio; c) acquiring distance information for the candidate user; and d) checking whether the candidate user is in an inner or outer cell area based on the distance information. If the candidate user is in the inner cell area, a subchannel group among subchannel groups having a Frequency Reuse Factor (FRF) lower than a threshold value is selected and subcarriers of the selected subchannel group is allocated. If the candidate user is in the outer cell area, a subchannel group among subchannel groups having a FRF higher than the threshold value is selected.
    Type: Application
    Filed: August 17, 2006
    Publication date: September 25, 2008
    Applicants: INHA-INDUSTRY PARTNERSHIP INSTITUTE, ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTIT
    Inventors: Hee-Soo Lee, Jae-Young Ahn, Kyung-Hi Chang, Joo Heo, In-Suk Cha
  • Publication number: 20080089278
    Abstract: Provided are a dynamic channel/power allocation method for an FRP-based OFDMA system and a frame/slot structure capable of supporting the dynamic channel/power allocation method. In the FRP-based OFDMA system, each of cells has an inner cell, an outer cell and a plurality of sectors and performs data communication with a plurality of MSs therein through one or more orthogonal subchannel groups. In the dynamic channel/power allocation method, a BS receives a feedback channel condition from an MS provided with a service of the BS and allocates a subchannel group with a high SINR to each MS in consideration of the fairness and the distance information of each MS. Power is allocated to each MS on the basis of the conditions of a channel allocated to each MS, thereby obtaining a multi-user diversity gain.
    Type: Application
    Filed: October 11, 2006
    Publication date: April 17, 2008
    Inventors: Kyung Hi Chang, In Suk Cha, Joo Heo
  • Publication number: 20070237069
    Abstract: Provided are a multi-step channel prediction apparatus and method for adaptive transmission in an OFDM/FDD system. A channel prediction is preformed considering a time-varying characteristic of a channel changing within one slot, in addition to feedback and processing delay time between a transmitter and a receiver, and an adaptive transmission is performed. Therefore, a target PER performance can be maintained without degradation of the system performance.
    Type: Application
    Filed: February 12, 2007
    Publication date: October 11, 2007
    Inventors: Kyung Hi Chang, Joo Heo