Patents by Inventor Ho-Jun Keum

Ho-Jun Keum 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: 7869710
    Abstract: An optical network unit (ONU) of an Ethernet passive optical network (EPON) and a control method thereof eliminates or substantially reduces instances of an ONU transmitting in time slots other than its allocated time slot. The ONU includes: a medium access controller for accessing a medium without temporal overlapping in order to transmit during one or more allocated TDM time slots without collision in upstream transmission to an optical line terminal; a burst-mode optical transceiver having a separately allocated wavelength before outputting the signal in the upstream transmission; and a complex programmable logic device for controlling an optical output of the burst-mode optical transceiver by monitoring an optical-output control signal from the medium access controller. An erroneous output from an ONU malfunction can be prevented from by cutting off the output once the duration of the allocated time slot has been reached.
    Type: Grant
    Filed: August 15, 2007
    Date of Patent: January 11, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hong-Gi Lee, Ho-Jun Keum, Jae-Hwang Ryu, Soon-Ho Jang
  • Publication number: 20080044185
    Abstract: An optical network unit (ONU) of an Ethernet passive optical network (EPON) and a control method thereof eliminates or substantially reduces instances of an ONU transmitting in time slots other than its allocated time slot. The ONU includes: a medium access controller for accessing a medium without temporal overlapping in order to transmit during one or more allocated TDM time slots without collision in upstream transmission to an optical line terminal; a burst-mode optical transceiver having a separately allocated wavelength before outputting the signal in the upstream transmission; and a complex programmable logic device for controlling an optical output of the burst-mode optical transceiver by monitoring an optical-output control signal from the medium access controller. An erroneous output from an ONU malfunction can be prevented from by cutting off the output once the duration of the allocated time slot has been reached.
    Type: Application
    Filed: August 15, 2007
    Publication date: February 21, 2008
    Inventors: Hong-Gi Lee, Ho-Jun Keum, Jae-Hwang Ryu, Soon-Ho Jang