Patents by Inventor Ki-Man Choi

Ki-Man Choi 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: 9838218
    Abstract: A method and a system for providing an overlay network interworking with an underlay network are disclosed.
    Type: Grant
    Filed: October 24, 2014
    Date of Patent: December 5, 2017
    Assignee: KT Corporation
    Inventor: Ki Man Choi
  • Publication number: 20160365931
    Abstract: In an RN configuration for providing a new service in a PON, it is possible to configure the RN remotely by instantaneous powering from a remote site only when necessary, while the RN being operated as a PON at ordinary times. More specifically, an RN configuration for providing a new service in a PON according to the present invention includes a power generation block capable of providing energy necessary for activating the RN by instantaneously supplied power from the remote site. Further, an RN according to the present invention further includes either one or both of a control agent block capable of controlling and managing optical paths of the RN by using power generated from the power generation block; and a reconfigurable switching block capable of configuring and switching the optical path of the RN through the power being provided from the power generation block and a control by the control agent block.
    Type: Application
    Filed: December 19, 2013
    Publication date: December 15, 2016
    Applicant: KOREA ADVANCED INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Chang-Hee LEE, Jong-Hoon LEE, Ki-Man CHOI, Sil-Gu MUN, Jung-Hyung MOON, Hoon-Keun LEE
  • Publication number: 20160269198
    Abstract: A method and a system for providing an overlay network interworking with an underlay network are disclosed.
    Type: Application
    Filed: October 24, 2014
    Publication date: September 15, 2016
    Applicant: KT CORPORATION
    Inventor: Ki Man CHOI
  • Patent number: 8442400
    Abstract: The present invention discloses a wavelength-division multiplexing passive optical network (WDM-PON) capable of high-bandwidth transmission for optical signals by using modulation format having high spectral efficiency. The WDM-PON according to the present invention provides a larger capacity and higher bandwidth transmission economically (at lower costs) by using a modulation format where spectral efficiency (a transmission bit number per a unit band width) is high, while using a low noise part of a light source.
    Type: Grant
    Filed: November 3, 2011
    Date of Patent: May 14, 2013
    Inventors: Chang-Hee Lee, Ki-Man Choi, Sil-Gu Mun, Jung-Hyung Moon
  • Patent number: 8290370
    Abstract: Disclosed is a wavelength division multiplexing passive optical network for simultaneously providing a broadcasting service and a data service by employing a broadband light source, which uses mutually injected Fabry-Perot laser diodes, as well as a central office used for the same.
    Type: Grant
    Filed: September 19, 2006
    Date of Patent: October 16, 2012
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Chang-Hee Lee, Jung-Hyung Moon, Ki-Man Choi
  • Publication number: 20120051749
    Abstract: The present invention discloses a wavelength-division multiplexing passive optical network (WDM-PON) capable of high-bandwidth transmission for optical signals by using modulation format having high spectral efficiency. The WDM-PON according to the present invention provides a larger capacity and higher bandwidth transmission economically (at lower costs) by using a modulation format where spectral efficiency (a transmission bit number per a unit band width) is high, while using a low noise part of a light source.
    Type: Application
    Filed: November 3, 2011
    Publication date: March 1, 2012
    Inventors: Chang-Hee Lee, Ki-Man Choi, Sil-Gu Mun, Jung-Hyung Moon
  • Patent number: 8116628
    Abstract: The present invention relates to a wavelength-division multiplexed passive optical network (WDM-PON) which embodies wavelength-independence of wavelength-locked Fabry Perot-Laser Diode (F-P LD).
    Type: Grant
    Filed: July 11, 2006
    Date of Patent: February 14, 2012
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Chang-Hee Lee, Ki-Man Choi
  • Patent number: 8078061
    Abstract: The present invention discloses a wavelength-division multiplexing passive optical network (WDM-PON) capable of high-bandwidth transmission for optical signals by using modulation format having high spectral efficiency. The WDM-PON according to the present invention provides a larger capacity and higher bandwidth transmission economically (at lower costs) by using a modulation format where spectral efficiency (a transmission bit number per a unit band width) is high, while using a low noise part of a light source.
    Type: Grant
    Filed: November 14, 2006
    Date of Patent: December 13, 2011
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Chang-Hee Lee, Ki-Man Choi, Sil-Gu Mun, Jung-Hyung Moon
  • Patent number: 8073334
    Abstract: The present invention relates to an optical modulation method and optical modulation system of a wavelength locked Fabry Perot-Laser Diode (FP-LD) by injecting a broadband light source (BLS) using mutual injection of FP-LDs. More specifically, the present invention relates to a novel modulation technology which embodies a wavelength locked FP-LD capable of being used as an economic light source in an optical network based on a wavelength-division multiplexing passive optical network (WDM-PON).
    Type: Grant
    Filed: November 8, 2005
    Date of Patent: December 6, 2011
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Chang-Hee Lee, Ki-Man Choi
  • Publication number: 20110255860
    Abstract: The present invention discloses a fault localization method and a fault localization apparatus in a Passive Optical Network (PON) and a passive optical network having the same. A fault localization method in PON according to the present invention comprises a) configuring an optical path of a remote node (RN) selectively by electric power being fed temporarily only when necessary, while the PON is regularly being operated as a passive network; and b) detecting a fault occurring on the selectively configured optical path by inserting a monitoring signal of an OTDR unit, which is positioned in a central office (CO), through the selectively configured optical path.
    Type: Application
    Filed: October 9, 2009
    Publication date: October 20, 2011
    Applicant: KOREA ADVANCED INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Chang-Hee Lee, Jong-Hoon Lee, Ki-Man Choi, Sil-Gu Mun, Jung-Hyung Moon, Jung-eun Moon, Hoon-Keun Lee, Joon-Young Kim, Sang-Min Oh
  • Patent number: 7936994
    Abstract: Disclosed is a broadband light source (BLS) necessary to implement wavelength-locked Fabry-Perot (FP) laser diodes (LDs) applicable to an optical subscriber network The BLS is based on a method using mutual injection of low-cost FP LDs and a method using FP LDs undergoing chirping. A power level of a light emitting diodes (LED), an erbium-doped fiber amplifier (EDFA), or a super luminescent diode (SLD) used as the conventional BLS is low and its cost is high, such that the conventional BLS is inefficient. However, the present invention can easily implement a low-cost BLS using proposed FP LDs.
    Type: Grant
    Filed: December 22, 2004
    Date of Patent: May 3, 2011
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Chang-Hee Lee, Jin-serk Baik, Ki-Man Choi, Hyun-Sik Min, Keun-Youl Park
  • Patent number: 7912372
    Abstract: The present invention relates to a passive optical network, which inexpensively improves the spectral efficiency of an access network and is capable of increasing the number of subscribers per channel by using WDM in combination with Time Division Multiplexing (TDM) or SubCarrier Multiple Access (SCMA) to expand a conventional WDM passive optical network.
    Type: Grant
    Filed: June 24, 2005
    Date of Patent: March 22, 2011
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Chang Hee Lee, Jin Serk Baik, Keun Youl Park, Seung Hyun Jang, Ki Man Choi, Hyun Sik Min
  • Publication number: 20100290782
    Abstract: The present invention discloses a remote node (RN) configuration for providing an enhanced service in a passive optical network and a passive optical network (PON) having the same. In an RN configuration for providing a new service in a PON according to the present invention, it is possible to configure the RN remotely by instantaneous powering from a remote site only when necessary, while the RN being operated as a PON at ordinary times. More specifically, an RN configuration for providing a new service in a PON according to the present invention includes a power generation block capable of providing energy necessary for activating the RN by instantaneously supplied power from the remote site.
    Type: Application
    Filed: October 10, 2007
    Publication date: November 18, 2010
    Applicant: KOREA ADVANCED INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Chang-Hee Lee, Jong-Hoon Lee, Ki-Man Choi, Sil-Gu Mun, Jung-Hyung Moon, Hoon-Keun Lee
  • Patent number: 7773838
    Abstract: The present invention discloses a network architecture for upgrading a legacy time division multiplexing-passive optical network (TDM-PON) to a wavelength division multiplexing-passive optical network (WDM-PON) based next-generation passive optical network (next-generation PON), wherein the legacy TDM-PON comprises: a central office (CO) having a first optical line termination (OLT); a remote node (RN) having a splitter; a single mode fiber (SMF) connecting the first OLT and the splitter; and a first group of one or more optical network terminations (ONTs) being connected to the splitter by a first group of one or more distribution fibers, and wherein the network architecture further comprises: in case that the next-generation PON is a WDM-PON, a first apparatus for combining and splitting wavelength bands being positioned between the SMF and the first OLT, in order to add a second OLT to be used for the WDM-PON within the CO or within another CO which is located in a position different from the CO, while sha
    Type: Grant
    Filed: November 14, 2006
    Date of Patent: August 10, 2010
    Assignee: LG-Nortel Co., Ltd.
    Inventors: Chang-Hee Lee, Ki-Man Choi, Sil-Gu Mun, Jung-Hyung Moon, Hoon-Keun Lee
  • Publication number: 20100054740
    Abstract: The present invention discloses a network architecture for upgrading a legacy time division multiplexing-passive optical network (TDM-PON) to a wavelength division multiplexing-passive optical network (WDM-PON) based next-generation passive optical network (next-generation PON), wherein the legacy TDM-PON comprises: a central office (CO) having a first optical line termination (OLT); a remote node (RN) having a splitter; a single mode fiber (SMF) connecting the first OLT and the splitter; and a first group of one or more optical network terminations (ONTs) being connected to the splitter by a first group of one or more distribution fibers, and wherein the network architecture further comprises: in case that the next-generation PON is a WDM-PON, a first apparatus for combining and splitting wavelength bands being positioned between the SMF and the first OLT, in order to add a second OLT to be used for the WDM-PON within the CO or within another CO which is located in a position different from the CO, while sha
    Type: Application
    Filed: November 14, 2006
    Publication date: March 4, 2010
    Applicant: KOREA ADVANCED INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Chang-Hee Lee, Ki-Man Choi, Sil-Gu Mun, Jung-Hyung Moon, Hoon-Keun Lee
  • Publication number: 20090196612
    Abstract: The present invention relates to an optical modulation method and optical modulation system of a wavelength locked Fabry Perot-Laser Diode (FP-LD) by injecting a broadband light source (BLS) using mutual injection of FP-LDs. More specifically, the present invention relates to a novel modulation technology which embodies a wavelength locked FP-LD capable of being used as an economic light source in an optical network based on a wavelength-division multiplexing passive optical network (WDM-PON).
    Type: Application
    Filed: November 8, 2005
    Publication date: August 6, 2009
    Inventors: Chang-Hee Lee, Ki-Man Choi
  • Publication number: 20090185807
    Abstract: Disclosed is a wavelength division multiplexing passive optical network for simultaneously providing a broadcasting service and a data service by employing a broadband light source, which uses mutually injected Fabry-Perot laser diodes, as well as a central office used for the same.
    Type: Application
    Filed: September 19, 2006
    Publication date: July 23, 2009
    Inventors: Chang-Hee Lee, Jung-Hyung Moon, Ki-Man Choi
  • Publication number: 20090092390
    Abstract: The present invention relates to a wavelength-division multiplexed passive optical network (WDM-PON) which embodies wavelength-independence of wavelength-locked Fabry Perot-Laser Diode (F-P LD).
    Type: Application
    Filed: July 11, 2006
    Publication date: April 9, 2009
    Inventors: Chang-Hee Lee, Ki-Man Choi
  • Publication number: 20080232807
    Abstract: The present invention discloses a wavelength-division multiplexing passive optical network (WDM-PON) capable of high-bandwidth transmission for optical signals by using modulation format having high spectral efficiency. The WDM-PON according to the present invention provides a larger capacity and higher bandwidth transmission economically (at lower costs) by using a modulation format where spectral efficiency (a transmission bit number per a unit band width) is high, while using a low noise part of a light source.
    Type: Application
    Filed: November 14, 2006
    Publication date: September 25, 2008
    Inventors: Chang-Hee Lee, Ki-Man Choi, Sil-Gu Mun, Jung-Hyung Moon
  • Publication number: 20080131127
    Abstract: Disclosed is a broadband light source (BLS) necessary to implement wavelength-locked Fabry-Perot (FP) laser diodes (LDs) applicable to an optical subscriber network The BLS is based on a method using mutual injection of low-cost FP LDs and a method using FP LDs undergoing chirping. A power level of a light emitting diodes (LED), an erbium-doped fiber amplifier (EDFA), or a super luminescent diode (SLD) used as the conventional BLS is low and its cost is high, such that the conventional BLS is inefficient. However, the present invention can easily implement a low-cost BLS using proposed FP LDs.
    Type: Application
    Filed: December 22, 2004
    Publication date: June 5, 2008
    Applicant: KOREA ADVANCED INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Chang-Hee Lee, Jin-Serk Baik, Ki-Man Choi, Hyun-Sik Min, Keun-Youl Park