Inwoong W Kim

8204389, Jun 19, 2012

Jan 9, 2009

12/351444

Guifang Li - Oviedo FL, US
Eduardo Mateo - Orlando FL, US
Likai Zhu - Orlando FL, US
Xiaoxu Li - Orlando FL, US
Gilad Goldfarb - Sunnyvale CA, US
Xin Chen - Beijing, CN
Inwoong Kim - Allen TX, US
Fatih Yaman - Oviedo FL, US

University of Central Florida Research Foundation, Inc. - Orlando FL

H04B 10/06

398208, 398209, 398202, 398 81, 398 45

Systems and method of compensating for transmission impairment are disclosed. One such method comprises: receiving an optical signal which has been distorted in the physical domain by an optical transmission channel; and propagating the distorted optical signal backward in the electronic domain in a corresponding virtual optical transmission channel.

8270835, Sep 18, 2012

Mar 31, 2010

12/751548

Kevin Croussore - San Jose CA, US
Inwoong Kim - Allen TX, US
Olga I. Vassilieva - Plano TX, US

Fujitsu Limited - Kawasaki

H04J 14/02
H04B 10/12
H04B 10/00

398 81, 398147, 398148, 398158, 398159

A method for reducing cross-phase modulation in an optical signal includes receiving an optical signal comprising a plurality of channels, wherein the information being communicated in a first set of one or more of the channels is modulated using one or more single-polarization modulation techniques and wherein the information being communicated in a second set of one or more of the channels is modulated using one or more dual-polarization modulation techniques. The method also includes splitting the optical signal into at least a first copy of the optical signal and a second copy of the optical signal and terminating the second set of channels in the first copy. Furthermore, the method includes applying a differential group delay to the second copy, the differential group delay introducing a walk-off between symbols communicated in a first polarization component of the second set of channels and the symbols of a second polarization component of the second set of channels. In addition, the method includes terminating the first set of channels in the second copy, combining the first set of channels in the first copy and the second set of channels in the second copy, and forwarding the combined channels.

8335438, Dec 18, 2012

Oct 30, 2009

12/609177

Inwoong Kim - Allen TX, US
Takao Naito - Plano TX, US

Fujitsu Limited - Kawasaki-shi

H04B 10/00

398154, 398162, 398163, 398202, 398203, 398204, 398205, 398206, 398207, 398208, 398209

According to particular embodiments, a signal communicated from a transmitter to a receiver is received. A frequency offset estimate of the signal is determined. The frequency offset estimate indicates a frequency difference between the transmitter and the receiver. The frequency offset estimate is provided as feedback. A next frequency offset is compensated for according to the feedback.

8447182, May 21, 2013

Sep 30, 2010

12/895371

Martin Bouda - Plano TX, US
Inwoong Kim - Allen TX, US
Takao Naito - Tokyo, JP

Fujitsu Limited - Kawasaki-shi

H04J 14/02

398 79, 398 68, 398 69, 398 91, 398 95

According to one embodiment, a system for transmitting an optical signal comprises a traffic distribution circuit configured to distribute traffic to a plurality of wavelength division multiplexer (WDM) modules. The system further comprises a first WDM module and a second WDM module. The first and second WDM modules each comprise a plurality of tunable optical transmitters, with each transmitter associated with a different wavelength band of a plurality of wavelength bands. Each transmitter in the first and second WDM modules is also tuned to transmit optical signals in channels included within the associated wavelength band of the transmitter. The first and second WDM modules each comprise a multiplexer configured to combine the optical signals transmitted from the plurality of transmitters into optical signals. The system further comprises a cyclic multiplexer configured to combine the optical signals from the first and second WDM modules into an optical output signal.

8467690, Jun 18, 2013

Sep 10, 2010

12/879242

Inwoong Kim - Allen TX, US
Takao Naito - Plano TX, US
Olga I. Vassilieva - Plano TX, US

Fujitsu Limited - Kawasaki-shi

H04B 10/18
H04B 10/04

398194, 398 29, 398147, 398 81

Methods and systems are provided for cancellation of chromatic dispersion combined laser phase noise. A method may include measuring a differential of laser phase noise using two optical pilot signals, the pilot signals each having a different optical frequency, or using an optical carrier and a pilot signal. The method may also include determining an approximate laser phase noise present in an optical system based on the measured differential of laser phase noise. The method may further include compensating for laser phase noise based on the determined approximate laser phase noise.

8488979, Jul 16, 2013

Dec 23, 2009

12/646792

Inwoong Kim - Allen TX, US
Takao Naito - Plano TX, US

Fujitsu Limited - Kawasaki-shi

H04B 10/04
H04B 10/12

398185, 398184, 398188

An apparatus for use with an optical computation system may comprise a monolithic device with no free space optical components and may include a phase modulator and a polarization modulator. The phase modulator may be configured to receive a beam of light and two digital data streams and operable to modulate the phase of the beam of light to at least four phase states, the at least four phase states representing the two digital data streams. The polarization modulator may be configured to receive two additional digital data streams and the modulated beam of light from the phase modulator and operable to modulate the polarization of the beam of light to at least four polarization states, the at least four polarization states representing the two additional digital data streams.

8543000, Sep 24, 2013

Sep 10, 2010

12/879792

Olga I Vassilieva - Plano TX, US
Inwoong Kim - Allen TX, US

Fujitsu Limited - Kawasaki-shi

H04J 14/02

398 81, 398159, 398147, 398 65, 398152

In accordance with the present disclosure a system for reducing polarization dependent loss (PDL) of an optical signal comprises a delay module coupled to one or more PDL inducing network elements of an optical network. The delay module is configured to time interleave a first polarization component with respect to a second polarization component of the optical signal. The time interleaving reduces interference caused by cross-talk components associated with the first and second polarization components and induced by the PDL of the PDL inducing elements.

8559829, Oct 15, 2013

Jul 5, 2011

13/176643

Inwoong Kim - Allen TX, US
Paparao Palacharla - Richardson TX, US
Xi Wang - Murphy TX, US
Motoyoshi Sekiya - Richardson TX, US

Fujitsu Limited - Kawasaki-shi

H04B 10/06
H04J 14/00

398208, 398 76, 398202, 398203

In accordance with some embodiments of the present disclosure a method for receiving and processing an optical orthogonal frequency-division multiplexed signal containing a plurality of traffics comprises receiving the optical orthogonal frequency-division multiplexed signal. The method further comprises down-converting the optical orthogonal frequency-division multiplexed signal into the electrical domain to obtain an electrical signal; filtering the electrical signal to obtain a first portion of the electrical signal containing a first of the plurality of traffics and preprocessing the first portion of the electrical signal in a first parallel preprocessor; filtering the electrical signal to obtain a second portion of the electrical signal containing a second of the plurality of traffics and preprocessing the second portion of the electrical signal in a second parallel preprocessor; and combining the preprocessed first and second portions of the electrical signal to yield a combined electrical signal and demodulating the combined electrical signal.