Search Results - "Sun Hyok Chang, Sun Hyok Chang"

Feedforward Phase Estimation for Real-Time PTBC Decoding in High-Speed Optical Access Networks by Rha, Hae Young, Moon, Sang-Rok, Chang, Sun-Hyok, Oh, Jung-Yeol, Kang, Hun-Sik

“…The surge in data demand fueled by data hungry applications has driven the need for enhanced capacity in sixth-generation (6G) mobile technology. To address…”
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Impact of Quadrature Imbalance in Optical Coherent QPSK Receiver by Sun Hyok Chang, Sun Hyok Chang, Hwan Seok Chung, Hwan Seok Chung, Kwangjoon Kim, Kwangjoon Kim

“…In this letter, we present the impact of quadrature imbalance in an optical coherent quadrature phase-shift-keying (QPSK) receiver. Arbitrary conjugate…”
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Transmission of Multiple HD-TV Signals Over a Wired/Wireless Line Millimeter-Wave Link With 60 GHz by Hwan Seok Chung, Hwan Seok Chung, Sun Hyok Chang, Sun Hyok Chang, Jong Dae Park, Jong Dae Park, Moo-Jung Chu, Moo-Jung Chu, Kwangjoon Kim, Kwangjoon Kim

“…For the first time to our knowledge, we demonstrate a transmission of 37 channels a 64 quadratic-amplitude-modulation (QAM)-coded high-definition television…”
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Suppression of transient phenomena in hybrid Raman/EDF amplifier by Sun Hyok Chang, Sun Hyok Chang, Hee Sang Chung, Hee Sang Chung, Hyun Jae Lee, Hyun Jae Lee, Kwangjoon Kim, Kwangjoon Kim

“…Transient phenomena of hybrid Raman/erbium-doped fiber amplifier (EDFA) upon optical channel add-drop are investigated. The transient responses of surviving…”
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Alamouti-coded DSP algorithm with a simplified PTBC decoder for next-generation optical access networks by Oh, Jung-Yeol, Moon, Sang-Rok, Chang, Sun-Hyok, Kang, Hun-Sik

“…The use of Alamouti-coded polarization-time block code (A-PTBC) in combination with a simple single polarization coherent receiver enables phase-diverse…”
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Reduction of temperature-dependent gain in L-band EDFA using antimony-aluminum codoped silica EDF by Young-Eun Im, Kyunghwan Oh, Sun Hyok Chang, Kwangjoon Kim, DiGiovanni, D.J.

“…We report a novel technique to suppress the temperature-dependent gain (TDG) of an L-band erbium-doped fiber amplifier. The composite optical gain block…”
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Mode- and wavelength-division multiplexed transmission using all-fiber mode multiplexer based on mode selective couplers by Chang, Sun Hyok, Chung, Hwan Seok, Ryf, Roland, Fontaine, Nicolas K, Han, Changyo, Park, Kyung Jun, Kim, Kwangjoon, Lee, Jyung Chan, Lee, Jong Hyun, Kim, Byoung Yoon, Kim, Young Kie

“…We propose all-fiber mode multiplexer composed of two consecutive LP₁₁ mode selective couplers that allows for the multiplexing of LP₀₁ mode and two-fold…”
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Effect of IQ Mismatch Compensation in an Optical Coherent OFDM Receiver by Chung, Hwan Seok, Chang, Sun Hyok, Kim, Kwangjoon

“…The performance enhancement using the Gram-Schmidt orthogonalization procedure (GSOP) for compensating transmitter (Tx) and receiver (Rx) in-phase/quadrature…”
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Widely tunable single-frequency Er-doped fiber laser with long linear cavity by Chang, Sun Hyok, Hwang, In Kag, Kim, Byoung Yoon, Park, Hee Gap

“…A widely tunable single-frequency Er-doped fiber laser is demonstrated in a 21-m-long linear cavity incorporating all-fiber acoustooptic frequency shifters and…”
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Mitigation of Imperfect Carver-Induced Phase Distortions in a Coherent PM-RZ-QPSK Receiver by Chung, Hwan Seok, Chang, Sun Hyok, Kim, Kwangjoon

“…The impact of phase distortions caused by imperfect return-to-zero (RZ) pulse carving on 112 Gb/s polarization-multiplexed…”
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Transient effects and gain-control method in low-noise dispersion-compensating hybrid fiber amplifier by Chang, Sun Hyok, Kim, Seung Kwan, Chung, Hee Sang, Chu, Moo-Jung

“…Transient effects in low-noise dispersion-compensating hybrid fiber amplifier (DC-HFA) are presented to show the combined dynamics of erbium-doped fiber…”
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Optimization of Operating Conditions for 112-Gb/s Polarization-Multiplexed 16-QAM Optical Modulation by Chang, Sun Hyok, Chung, Hwan Seok, Kim, Kwangjoon

“…In this letter, we analyze a 16-ary quadrature amplitude modulation (16-QAM) optical signal generated by applying four-level electrical signals to a single…”
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Digital non-data-aided symbol synchronization in optical coherent intradyne reception by Chang, Sun Hyok, Chung, Hwan Seok, Kim, Kwangjoon

“…Digital symbol synchronization of optical binary phase shift keying signals is experimentally demonstrated. Algorithm of timing error feedback is proposed for…”
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Distributed fiber Raman amplifiers with localized loss by Kim, Seung Kwan, Chang, Sun Hyok, Han, Jin Soo, Chu, Moo-Jung, Lee, Jong Hyun

“…Backward pumped C- and L-band distributed fiber Raman amplifiers are described, where discrete losses from 0-8 dB were added at various positions to examine…”
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Field Trial of 112 Gb/s Dual-Carrier DQPSK Channel Upgrade in Installed 516 km of Fiber Link and ROADM by Chung, Hwan Seok, Chang, Sun Hyok, Lee, Jyung Chan, Shin, Jongyoon, Youn, Ji Wook, Ko, JeSoo, Lee, Joon Ki, Kang, Sae-Kyoung, Huh, Joon Young, Lee, Jong Hyun, Lee, Won Hee, Hyun, Sung Kyu, Kang, Sun Moo, Kim, Kwangjoon

“…A field trial of 100GE signal transmission using dual-carrier differential quadrature phase shift keying (DC-DQPSK) based optical transceiver is demonstrated…”
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Optical Kerr effect in a direction-switched fiber laser gyroscope by Hyok Chang, Sun, Joon Ahn, Seong, Yoon Kim, Byoung

“…The operation of a direction-switched mode-locked fiber laser gyroscope is described. We observed a large bias in the beat frequency output, and found that it…”
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Companding transform based SPM compensation in coherent optical OFDM transmission by Hwan Seok Chung, Sun Hyok Chang, Kwangjoon Kim

“…We demonstrate a mitigation of fiber nonlinearity using μ-law companding transform in coherent optical OFDM transmission. After transmission of 1,040 km over…”
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Performance Evaluation of 100 Gb/s 16-QAM Alamouti-coded Optical Coherent System by Oh, Jung-Yeol, Moon, Sang-Rok, Chang, Sun-Hyok, Kang, Hun-Sik

“…Alamouti polarization time block coding (PTBC) coherent optical technology has been drawing attention as a technology for future optical access networks…”
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Automatic gain control in Raman amplifier with multi-wavelength pumps by Chang, Sun Hyok, Chung, Hee Sang, Kim, Kwangjoon, Ko, Je Soo

“…Automatic gain control method in Raman amplifier with multi-wavelength pumping scheme is presented. Monitoring of several channel power and feedback pump…”
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Bidirectional transmissions of 32 channels × 10 Gb/s over metropolitan networks using linear optical amplifiers by Chung, Hee Sang, Han, Jin Soo, Chang, Sun Hyok, Lee, Hyun Jae

“…This letter demonstrates bidirectional transmissions of 320 Gb/s (160 Gb/s per direction) over metropolitan networks using linear optical amplifiers (LOAs) as…”
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