公开(公告)号：US09998222B2

公开(公告)日：2018-06-12

申请号：US15245315

申请日：2016-08-24

Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE

Inventor： Chan Gyo Han ,  Min Kyu Sung ,  Jong Hyun Lee ,  Hwan Seok Chung ,  Seung Hyun Cho

IPC: H04B10/2513 ,  H04J1/02 ,  H04J14/02

CPC classification number: H04B10/2513 ,  H04B10/25753 ,  H04B10/548 ,  H04J1/02 ,  H04J14/0227

Abstract: An optical signal transmission system and method of allocating center frequencies of intermediate frequency (IF) carriers in a frequency division multiplexing (FDM) optical fiber link. The optical signal transmission method includes determining a center frequency interval between modulated signals based on a bandwidth of the modulated signals or a center frequency of a modulated signal having a lowest center frequency, among the modulated signals, reallocating center frequencies to the modulated signals based on the center frequency interval between the modulated signals, and converting the modulated signals reallocated the center frequencies from electrical signal into optical signal and transmitting the optical signal.

公开(公告)号：US09787401B2

公开(公告)日：2017-10-10

申请号：US15218240

申请日：2016-07-25

Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE

Inventor： Sun Hyok Chang ,  Kwang Joon Kim ,  Hyun Jae Lee ,  Chan Gyo Han

IPC: H04B10/27 ,  H04B10/25 ,  H04B10/2581 ,  H04B10/2587 ,  H04B10/272 ,  H04J14/08

CPC classification number: H04B10/27 ,  H04B10/25 ,  H04B10/2504 ,  H04B10/2581 ,  H04B10/2587 ,  H04B10/272 ,  H04J14/04 ,  H04J14/08

Abstract: A Mode Division Multiplexed Passive Optical Network (MDM-PON) apparatus includes: a non-mode selective multiplexer which includes a first end where three or more single-mode optical fibers are spaced apart from each other by a predetermined distance, and a second end where cores of the three or more single-mode optical fibers are tapered such that a gap between the three or more single-mode optical fibers is narrower than the predetermined distance while the three or more single-mode optical fibers are spaced apart from each other by an equal distance; an optical line terminal (OLT) which is connected to the second end through a few-mode fiber, and transmits a downstream optical signal; and three or more optical network units (ONUs) which is connected to the first end through the three or more single-mode optical fibers, and transmits upstream optical signals.

公开(公告)号：US10090928B2

公开(公告)日：2018-10-02

申请号：US15378194

申请日：2016-12-14

Applicant: Electronics and Telecommunications Research Institute

Inventor： Min Kyu Sung ,  Jong Hyun Lee ,  Hwan Seok Chung ,  Seung Hyun Cho ,  Chan Gyo Han

IPC: H04B10/00 ,  H04B10/2513 ,  H04B10/2575

Abstract: Provided is an analog optical transmission system using a dispersion management technique. The analog optical transmission system may include a digital unit (DU) pool including a plurality of DUs to transmit an optical signal; a plurality of radio units (RUs) to receive the optical signal; and one or more dispersion management apparatus to remove a signal distortion component caused by an interaction between a chirp and chromatic dispersion by compensating for the chromatic dispersion before the plurality of RUs receives the optical signal that is transmitted from the DU pool.

公开(公告)号：US10027415B2

公开(公告)日：2018-07-17

申请号：US15079714

申请日：2016-03-24

Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE

Inventor： Seung Hyun Cho ,  Jong Hyun Lee ,  Hwan Seok Chung ,  Chan Gyo Han

IPC: H04B10/25 ,  H04B10/2575

CPC classification number: H04B10/25753 ,  H04B10/25759

Abstract: An apparatus for transmitting a control signal in a radio-over-fiber (RoF)-based mobile fronthaul includes: a data channel transmitter configured to generate a data signal at a preassigned frequency or wavelength; a control channel transmitter configured to generate a control signal at a designated frequency or wavelength that is shared with other apparatuses; and a combiner configured to combine the data signal with the control signal.

公开(公告)号：US09787395B2

公开(公告)日：2017-10-10

申请号：US15007739

申请日：2016-01-27

Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE

Inventor： Hwan Seok Chung ,  Seung Hyun Cho ,  Jong Hyun Lee ,  Sang Soo Lee ,  Chan Gyo Han

IPC: H04B10/079 ,  H04B10/2575 ,  H04B10/50 ,  H04B10/564

CPC classification number: H04B10/07953 ,  H04B10/25759 ,  H04B10/50572 ,  H04B10/50575 ,  H04B10/564

Abstract: An optical fiber cable of a mobile fronthaul system based on a radio over fiber (RoF), which includes a control apparatus for monitoring an analog optical link according to an exemplary embodiment, may be monitored. The monitoring control apparatus may include an optical signal monitor to monitor an optical signal passing through an optical fiber cable, and a system controller to control the optical signal based on a result of the monitoring. The optical signal monitor may calculate an average optical power, carrier-to-noise ratio (CNR), and a size of a nonlinear component from an electrical signal, which has been acquired from the optical signal. Then, the optical signal monitor may control the calculated average optical power, CNR, and nonlinear component.