Browsing by Author "Chow, Chi-Wai"

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1.12-Tbit/s PAM-4 Enabled by a Silicon Photonic Transmitter Bridged With a 7-Channel MCF
(2020-08-01)
Tong, Yeyu
;
Chen, Guan-Hong
;
Wang, Yi
;
Zhang, Zunyue
;
Chan, David Weng U.
We demonstrate a high-capacity and ultra-compact silicon photonic transmitter directly coupled to a 7-channel multicore fiber (MCF). The integrated transmitter contains seven GeSi electro-absorption modulators (EAMs) connected with the perfectly vertical grating coupler (PVGC) array. A high port density for spatial-division multiplexing (SDM) is thus enabled by the out-of-plane coupling while not requiring angled polishing of the MCF. Relying on four-level pulse amplitude modulation (PAM-4) and digital signal processing (DSP), each of the EAMs can support a data rate of 160 Gbit/s in the back-to-back system. The obtained bit-error-rate (BER) is below the low-latency 7% hard-decision forward-error-correct (HD-FEC) coding limit. The integrated transmitter has a total data-rate-capacity of 1.12 Tbit/s over the seven spatial channels and a compact footprint of 1.8 mm x 0.45 mm. BER performance of the optimum spatial channel is evaluated at different wavelengths, revealing its potential for possible wavelength-division multiplexing (WDM) by the on-chip wavelength (de)multiplexers in the future.
1.7 to 2.3 Gbps OOK LED VLC Transmission Based on 4 x 4 Color-Polarization-Multiplexing at Extremely Low Illumination
(2019-08-01)
Yeh, Chien-Hung
;
Weng, Jui-Hung
;
Chow, Chi-Wai
;
Luo, Chien-Ming
;
Xie, Yue-Ru
To achieve the high traffic rate of a GaN LED-based visible light communication (VLC), a 4 x 4 color-polarization-multiplexing system is demonstrated by using two blue and two green LEDs. In the measurement, an available bandwidth of blue and green LEDs can be greater than 465 MHz for VLC modulation traffic by using the suitable analogy front end circuit. Hence, the proposed VLC system can deliver 1.7 to 2.3 Gbit/s ON-OFF keying traffic rates in the free space transmission length of 1-4 m under the extremely low illumination of 6.9-136.1 lux for the indoor application. Moreover, the measured BER of each LED is less than the forward error correction target of 3.8 x 10(-3) to maintain the better signal performance.
100-m Long Distance RGB Visible Light Camera Communication
(2018-01-01)
Liu, Yen-Chun
;
Shiu, Ruei-Jie
;
Wei, Liang-Yu
;
Hsu, Chin-Wei
;
Chow, Chi-Wai
We demonstrate and analyze using different ISO values to achieve a 100-m long distance visible light camera communication using red/green/blue (RGB) light-emitting-diodes (LEDs).
110 GHz hybrid mode-locked fiber laser with enhanced extinction ratio based on nonlinear silicon-on-insulator micro-ring-resonator (SOI MRR)
(2016-03)
Liu, Yang
;
Hsu, Yung
;
Chow, Chi-Wai
;
Yang, Ling-Gang
;
Yeh, Chien-Hung
We propose and experimentally demonstrate a new 110 GHz high-repetition-rate hybrid mode-locked fiber laser using a silicon-on-insulator microring-resonator (SOI MRR) acting as the optical nonlinear element and optical comb filter simultaneously. By incorporating a phase modulator (PM) that is electrically driven at a fraction of the harmonic frequency, an enhanced extinction ratio (ER) of the optical pulses can be produced. The ER of the optical pulse train increases from 3 dB to 10 dB. As the PM is only electrically driven by the signal at a fraction of the harmonic frequency, in this case 22 GHz (110 GHz/5 GHz), a low bandwidth PM and driving circuit can be used. The mode-locked pulse width and the 3 dB spectral bandwidth of the proposed mode-locked fiber laser are measured, showing that the optical pulses are nearly transform limited. Moreover, stability evaluation for an hour is performed, showing that the proposed laser can achieve stable mode-locking without the need for optical feedback or any other stabilization mechanism.
1250 Mbit/s OOK Wireless White-Light VLC Transmission Based on Phosphor Laser Diode
(2019-06-01)
Yeh, Chien-Hung
;
Chow, Chi-Wai
;
Weil, Liang-Yu
;
光電工程學系
;
光電工程研究所
In this work, for the first time, we demonstrate a 1250 Mbit/s ON-OFF keying whitelight visible light communication (VLC) transmission in a free space transmission length of 1 m by utilizing a yellow-phosphor laser diode (LD). Here, the blue optical filter, which is used to enhance the data rate by removing the yellow color component, is not required to. Besides, the wireless transmission lengths, illuminations, and modulation traffic rates of the proposed LD-based VLC system are analyzed and discussed.
192-Gbit/s PAM-4 Optical Interconnect using Mode-Division Multiplexing
(2018-01-01)
Hsu, Yung
;
Wu, Xinru
;
Chuang, Chun-Yen
;
Chow, Chi-Wai
;
Tsang, Hon Ki
192-Gbit/s pulse-amplitude-modulation-4 (PAM-4) signal transmission for on-chip optical interconnects using mode-division-multiplexing (MDM) is experimentally investigated. 3 channels are successfully mode multiplexed and de-multiplexed satisfying the forward-error correction (FEC) requirement.
2.333-Tbit/s bi-directional optical mobile networks using optical wireless communication (OWC)
(2020-11-15)
Wei, Liang-Yu
;
Chen, Shu-, I
;
Yeh, Chien-Hung
;
Liu, Yang
;
Chen, Guan-Hong
We propose and experimentally demonstrate a 2.333-Tbit/s bi-directional optical mobile network using optical wireless communication (OWC). The proposed network architecture is divided into: fronthaul network con-necting between the distributed-unit (DU) and the remote-radio-unit (RRU); and midhaul network connecting between the central unit (CU) and the DU. At the midhaul, an aggregated 2.333-Tbit/s transmission is achieved using wavelength division multiplexed (WDM) infrared (IR) based invisible light communication (IVLC). For the link between the RRU and user-equipment (UE), 2.7 Gbit/s white-light visible-light-communication (VLC) transmission is achieved for indoor 1.5 m transmission. It can provide communication and lighting simultaneously. A gateway (GW) is also proposed acting as the interface between the IVLC and VLC transmissions. In the proposed architecture, about 400 VLC end-users can be supported.
2.6 Tbit/s On-Chip Optical Interconnect Supporting Mode-Division-Multiplexing and PAM-4 Signal
(2018-06-01)
Hsu, Yung
;
Chuang, Chun-Yen
;
Wu, Xinru
;
Chen, Guan-Hong
;
Hsu, Chin-Wei
In this letter, we combine the use of dense-wavelength-division-multiplexing and mode-division-multiplexing (MDM) with advanced-modulation formats for on-chip optical interconnects. A three-mode MDM multiplexer (MUX) and de-multiplexer (DEMUX) was designed and used. Each wavelength carrier had an aggregate data rate of 192-Gbit/s using 4-level pulse-amplitude-modulation. The mode crosstalk of the MDM MUX/DEMUX was measured to he below -20 dB in the 40-nm wavelength band from 1520 to 1560 nm. Fourteen wavelength channels are multiplexed and successfully transmitted with an aggregate transmission capacity of 2.6 Tbit/s (14 wavelengths x 3 modes x 64 Gbit/s) with all channels satisfying the hard-decision forward-error-correction threshold. Numerical analysis of the mode crosstalk is also performed.
20 Gbit/s Tricolor R/G/B Laser Diode based Bi-directional Signal Remodulation Visible Light Communication System
(2018-01-01)
Wei, Liang-Yu
;
Hsu, Chin-Wei
;
Hsu, Yung
;
Chow, Chi-Wai
;
Yeh, Chien-Hung
We demonstrate a bi-directional signal-remodulated visible-light-communication (VLC) system using tricolor R/G/B laser diodes to produce a 20.231-Gbit/s orthogonal-frequency-division-multiplexed (OFDM) downstream signal and 2-Mbit/s remodulated on-off-keying (OOK) upstream signal.
20.231 Gbit/s tricolor red/green/blue laser diode based bidirectional signal remodulation visible-light communication system
(2018-05-01)
Wei, Liang-Yu
;
Hsu, Chin-Wei
;
Chow, Chi-Wai
;
Yeh, Chien-Hung
;
交大名義發表
We propose and experimentally demonstrate a recorded 1-m bidirectional 20.231-Gbit/s tricolor R/G/B laser diode (LD) based visible-light communication (VLC) system supporting signal remodulation. In the signal remodulation system, an LD source is not needed at the client side. The client reuses the downstream signal sent from the central office (CO) and remodulates it to produce the upstream signal. As the LD sources are located at the CO, the laser wavelength and temperature managements at the cost-sensitive client side are not needed. This is the first demonstration, to our knowledge, of a > 20 Gbit/s data rate tricolor R/G/B VLC signal transmission supporting upstream remodulation. (c) 2018 Chinese Laser Press
250-GHz Passive Harmonic Mode-Locked Er-Doped Fiber Laser by Dissipative Four-Wave Mixing With Silicon-Based Micro-Ring
(2013-10-01)
Jyu, Siao-Shan
;
Yang, Ling-Gang
;
Wong, Chi-Yan
;
Yeh, Chien-Hung
;
Chow, Chi-Wai
We propose and demonstrate a 250-GHz high-repetition-rate mode-locked Er-doped fiber laser, which utilizes a silicon micro-ring resonator (SMRR). The SMRR acts as an optical comb filter to help achieve passive mode-locking through the dissipative four-wave-mixing effect induced by a piece of high nonlinear fiber. A short section of polarization-maintaining fiber is inserted in the cavity to induce birefringence filtering to significantly enhance the stability of the proposed laser through the combined effects of optical filtering and nonlinear spectral broadening. The laser can operate about 2 and 6 nm in the case of 1.48-ps and 875-fs output pulsewidth, with 3-dB bandwidth, respectively. The laser can remain mode locked, during our measurement time, without any cavity length or temperature feedback control.
40 Gb/s on-off keying downstream and 10 Gb/s on-off keying remodulated upstream signals in long-reach access network with multivideo services
(2011-12-01)
Yeh, Chien-Hung
;
Chow, Chi-Wai
;
Liu, Yen-Liang
;
Pan, Ci-Ling
;
光電工程學系
In this demonstration, we propose and investigate a long reach passive optical network (PON) using four wavelength-multiplexed signals with both on-off keying modulations for 40 Gb/s downlink traffic in 100 km fiber transmission without dispersion compensation. In the exchange node, we can use four channels with video services broadcasting to each optical network unit (ONU) for the uplink signal remodulation. Hence, four wavelength-multiplexed video signals also can be used to inject into the corresponding reflective semiconductor optical amplifiers in each ONU for uplink signal remodulation to achieve a 4 x 2.5 Gb/s data rate. In addition, under the 32 split ratio PON system, the power penalties of nearly 6.7 and 1 dB could be measured at the bit error rate of 10(-9) for the downlink and uplink traffic, respectively. (C) 2011 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.3662395]
40-Gb/s Time-Division-Multiplexed Passive Optical Networks Using Downstream OOK and Upstream OFDM Modulations
(2010-01-15)
Yeh, Chien-Hung
;
Chow, Chi-Wai
;
Hsu, Chih-Hung
;
光電工程學系
;
Department of Photonics
In this investigation, we first propose and investigate a 40-Gb/s time-division-multiplexed passive optical network (TDM-PON) using four wavelength-multiplexed signals in both downstream and upstream traffic. Here, each downstream signal uses 10-Gb/s on-off keying (OOK) format encoded by a Mach-Zehnder modulator (MZM) in 1.5-mu m band. And each upstream channel utilizes the highly spectral efficient 10-Gb/s orthogonal frequency-division-multiplexing quadrature amplitude modulation (OFDM-QAM) generated by directly modulating a 1.3-mu m laser. Based on the proposed scheme, 40-Gb/s data traffic in a TDM-PON can be obtained easily by using four wavelength-multiplexed channels. In addition, the performance of the proposed PON architecture has also been discussed.
40-Gbit/s Visible Light Communication using Polarization-Multiplexed R/G/B Laser Diodes with 2-m Free-Space Transmission
(2019-01-01)
Wei, Liang-Yu
;
Hsu, Chin-Wei
;
Chow, Chi-Wai
;
Yeh, Chien-Hung
;
光電工程學系
We demonstrate a recorded 40.665-Gbit/s visible-light-communication (VLC) system using polarization multiplexed red/green/blue (R/G/B) laser-diodes (LDs) with 2-m free-space transmission. Bit-and-power-loading orthogonal-frequency-division-multiplexed (OFDM) signal is employed.
512-Gbit/s PAM-4 Signals Direct-Detection using Silicon Photonics Receiver with Volterra Equalization
(2018-01-01)
Hsu, Yung
;
Chuang, Chun-Yen
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Wei, Liang-Yu
;
Chow, Chi-Wai
;
Wu, Xinru
A 400-Gbit/s Ethernet (GbE) pulse-amplitude-modulation-4 (PAM-4) over 10-km single-mode-fiber (SMF) transmission direct-detected by an integrated silicon-photonics-receiver satisfying the IEEE P802.3bs requirement; and its feasibility to support 512-Gbit/s were illustrated.
56 Gb/s OOK transmission in robust and bend-insensitive GGP 80-m ultra-large-core (ULC) MMF for lightpeak
(2015-03-01)
Chow, Chi-Wai
;
Yang, Ling-Gang
;
Sung, Jiun-Yu
;
Su, Hong-Quan
;
Yeh, Chien-Hung
We demonstrate for the first time a recorded 56-Gb/s transmission in a new type robust and bend-insensitive glass-glass-polymer structured 80-m ultra-large-core multimode fiber (ULCMMF) using simple and single-polarization on-off-keying for Lightpeak. The LCMMF design is presented. Experimental results show that the ULCMMF could be a good choice for consumer applications in the near future.
62nm CW wavelength-selectable erbium-doped fiber compound-ring laser with stable single-mode output
(2019-12-01)
Yeh, Chien-Hung
;
Chang, Yao-Jen
;
Lin, Wen-Piao
;
Xie, Yue-Ru
;
Luo, Chien-Ming
In this demonstration, an erbium-doped fiber (EDF) based laser with stable, wide and wavelength-selectable single-longitudinal-mode (SLM) performances is designed and demonstrated. Here, to achieve SLM oscillation, a compound-ring scheme is constructed in the EDF laser cavity serving as a mode-restriction-filter for densely side-mode suppression. Moreover, the continuous-wave tunability can be scaled from 1520.0 to 1582.0 nm by using the proposed compound-ring scheme and commercial C-band EDF amplifier. In the measurement, the output stability and 3 dB Lorentzian linewidth of each lasing wavelength in the proposed EDF compound-ring laser have also been discussed.
64-Gbit/s PAM-4 20-km Transmission Using Silicon Micro-ring Modulator for Optical Access Networks
(2017-01-01)
Hsu, Yung
;
Tzu, Ta-Ching
;
Lin, Tien-Chien
;
Chung, Chun-Yen
;
Wu, Xinru
We demonstrate the feasibility of using silicon-micro-ring-modulators for 50-Gbitis and 64-Gbit/s pulse-amplitude-modulation-4 (PAM-4) communications in a 20-km single-mode fiber (SMF) link with Volterra-filtering. The integrated transmitter may be used in passive optical-access-networks with 20-kin-reach and 64-split-ratio.
A 110 GHz passive mode-locked fiber laser based on a nonlinear silicon-micro-ring-resonator
(2014-06-01)
Yang, Ling-Gang
;
Jyu, Siao-Shan
;
Chow, Chi-Wai
;
Yeh, Chien-Hung
;
Wong, Chi-Yan
Mode-locked fiber lasers have many important applications in science and engineering. In this work, we demonstrate for the first time a 110 GHz high repetition rate mode-locked fiber laser using a silicon-based micro-ring resonator (SMRR) to act as an intra-cavity optical comb filter, as well as an optical nonlinear element. No electrical bias for the SMRR is required to reduce free carrier absorption. The SMRR has a free spectral range of 0.88 nm, enforcing laser mode-locking at the 110 GHz high rate. The optical nonlinearity of the SMRR also supports the dissipative four-wave mixing effect for generating the mode-locked optical pulse trains. The mode-locked pulse-width, optical 3 dB spectral bandwidth and the time-bandwidth product (TBP) are experimentally measured under different pump currents to the erbium-doped fiber-amplifier module inside the laser cavity. The relative intensity noise and the line-width of the proposed laser are also evaluated. Furthermore, a long-term monitoring is performed. The experimental results show that the optical pulse train generated by the SMRR-based mode-locked fiber laser has a 2.6 ps pulse-width (pump current at 400 mA) at a 110 GHz high repetition rate, narrow line-width (1 kHz), high stability (under observation of an hour), and nearly Gaussian transform-limited (TBP is 0.455).
A 110 GHz passive mode-locked fiber laser based on a nonlinear silicon-micro-ring-resonator
(2014-06-01)
Yang, Ling-Gang
;
Jyu, Siao-Shan
;
Chow, Chi-Wai
;
Yeh, Chien-Hung
;
Wong, Chi-Yan
Mode-locked fiber lasers have many important applications in science and engineering. In this work, we demonstrate for the first time a 110 GHz high repetition rate mode-locked fiber laser using a silicon-based micro-ring resonator (SMRR) to act as an intra-cavity optical comb filter, as well as an optical nonlinear element. No electrical bias for the SMRR is required to reduce free carrier absorption. The SMRR has a free spectral range of 0.88 nm, enforcing laser mode-locking at the 110 GHz high rate. The optical nonlinearity of the SMRR also supports the dissipative four-wave mixing effect for generating the mode-locked optical pulse trains. The mode-locked pulse-width, optical 3 dB spectral bandwidth and the time-bandwidth product (TBP) are experimentally measured under different pump currents to the erbium-doped fiber-amplifier module inside the laser cavity. The relative intensity noise and the line-width of the proposed laser are also evaluated. Furthermore, a long-term monitoring is performed. The experimental results show that the optical pulse train generated by the SMRR-based mode-locked fiber laser has a 2.6 ps pulse-width (pump current at 400 mA) at a 110 GHz high repetition rate, narrow line-width (1 kHz), high stability (under observation of an hour), and nearly Gaussian transform-limited (TBP is 0.455).