Browsing by Author "Chen, Guan-Hong"

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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.
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.
Adaptive filtering for white-light LED visible light communication
(2017-01)
Hsu, Chin-Wei
;
Chen, Guan-Hong
;
Wei, Liang-Yu
;
Chow, Chi-Wai
;
Lu, I-Cheng
White-light phosphor-based light-emitting diode (LED) can be used to provide lighting and visible light communication (VLC) simultaneously. However, the long relaxation time of phosphor can reduce the modulation bandwidth and limit the VLC data rate. Recent VLC works focus on improving the LED modulation bandwidths. Here, we propose and demonstrate the use of adaptive Volterra filtering (AVF) to increase the data rate of a white-light LED VLC system. The detailed algorithm and implementation of the AVF for the VLC system have been discussed. Using our proposed electrical frontend circuit and the proposed AVF, a significant data rate enhancement to 700.68 Mbit/s is achieved after 1-m free-space transmission using a single white-light phosphor-based LED. (C) 2017 Society of Photo-Optical Instrumentation Engineers (SPIE)
Adaptive filtering for white-light LED visible light communication
(2017-01-01)
Hsu, Chin-Wei
;
Chen, Guan-Hong
;
Wei, Liang-Yu
;
Chow, Chi-Wai
;
Lu, I-Cheng
White-light phosphor-based light-emitting diode (LED) can be used to provide lighting and visible light communication (VLC) simultaneously. However, the long relaxation time of phosphor can reduce the modulation bandwidth and limit the VLC data rate. Recent VLC works focus on improving the LED modulation bandwidths. Here, we propose and demonstrate the use of adaptive Volterra filtering (AVF) to increase the data rate of a white-light LED VLC system. The detailed algorithm and implementation of the AVF for the VLC system have been discussed. Using our proposed electrical frontend circuit and the proposed AVF, a significant data rate enhancement to 700.68 Mbit/s is achieved after 1-m free-space transmission using a single white-light phosphor-based LED. (C) 2017 Society of Photo-Optical Instrumentation Engineers (SPIE)
Compact 84 GHz passive mode-locked fiber laser using dual-fiber coupled fused-quartz microresonator
(2017-10-01)
Liu, Tze-An
;
Hsu, Yung
;
Chow, Chi-Wai
;
Chuang, Yi-Chen
;
Ting, Wei-Jo
We propose and demonstrate a compact and portable-size 84-GHz passive mode-locked fiber laser, in which a dual-fiber coupled fused-quartz microresonator is employed as the intracavity optical comb filter as well as the optical nonlinear material for optical frequency comb generation. About eight coherent optical tones can be generated in the proposed fiber laser. The 20-dB bandwidth is larger than 588 GHz. The full-width halfmaximum pulse-width of the proposed laser is 2.5 ps. We also demonstrate the feasibility of using the proposed passive mode-locked fiber laser to carry a 5-Gbit/s on-off-keying signal and transmit over 20-km standard single mode fiber. A 7% forward error correction requirement can be achieved, showing the proposed fiber laser can be a potential candidate for fiber-wireless applications. (C) 2017 Society of Photo-Optical Instrumentation Engineers (SPIE)
Current Integral Method for Fine Commutation Tuning of Sensorless Brushless DC Motor
(2017-12-01)
Lee, An-Chen
;
Fan, Chia-Juei
;
Chen, Guan-Hong
;
機械工程學系
;
Department of Mechanical Engineering
This paper presents a method for fine commutation tuning of brushless direct current (BLDC) motor. First, we analyze the phase current waveform under commutation error and nonideal back-EMF. From the relationship derived, we propose a feedback compensation method in combination with a sensored BLDC motor or any sensorless drive technique to adjust commutation instant by forcing the current integrals of the two half periods in one 60 degrees conducting period to be equal. The method is robust to variations in resistance and inductance, as well as to nonideal back-EMF, pushing the peak values of the current waveform at the front and back of each conducting period to be more identical. Simulations are presented and a digital signal processor (DSP)-based sensorless scheme contingent on a disturbance observer for back electromotive force (back-EMF) estimation in combination with the proposed control method is implemented to verify its effectiveness experimentally. The results show that proposed method is capable of running the motor at different speeds, load torque, and under the speed-varying operating condition with low levels of motor vibration and power consumption.
Design of Silicon Photonics Based Enhanced Evanescent Coupling Mode-Division Multiplexer and De-multiplexer for Footprint Reduction
(2019-01-01)
Peng, Ching-Wei
;
Cheng, Ming-Wei
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Chen, Guan-Hong
;
Guo, Pin-Cheng
;
Tsai, Jui-Feng
A design of silicon-photonics (SiPh) based 4 x 4 enhanced-evanescent-coupling mode-division-multiplexing (EEC-MDM) multiplexer/de-multiplexer is proposed. Compared with the traditional MDM, our proposed EEC-MDM can significantly reduce the footprint while archiving similar coupling efficiencies.
Digital Signal Processing for Visible Light Communication Applications
(2019-01-01)
Chow, Chi-Wai
;
Chen, Guan-Hong
;
Peng, Ching-Wei
;
Wei, Liang-Yu
;
Yeh, Chien-Hung
We reviewed our resent works using digital-signal-processing (DSP) techniques to improve visible-light-communication (VLC). A rolling-shutter-effect (RSE) light-panel and CMOS image-sensor based VLC and a visible-light-positioning (VLP) system using machine learning are discussed.
Integrated Silicon Photonics Remote Radio Frontend (RRF) for Single-Sideband (SSB) Millimeter-Wave Radio-Over-Fiber (ROF) Systems
(2019-04-01)
Tong, Yeyu
;
Chow, Chi-Wai
;
Chen, Guan-Hong
;
Peng, Ching-Wei
;
Yeh, Chien-Hung
Radio-over-fiber (ROF)-based mobile fronthaul network supporting the baseband unit and simple remote radio head is a promising network architecture for future wireless networks. In this paper, we propose and demonstrate a silicon photonics (SiPh)-based remote radio frontend (RRF) for the mm-wave ROF systems. The proposed SiPh-based RRF consisted of an integrated Mach-Zehnder modulator and a micro-ring modulator, producing a single-sideband 40 GHz millimeter-wave orthogonal-frequency-division-multiplexing ROF signal, which is robust against fiber chromatic dispersion in the mobile fronthaul transmission. The RRF is fabricated using SiPh platform and could be potentially low cost. High split-ratios can be potentially achieved. Data rate of 7.813 Gbit/s per wavelength channel is achieved in the experiment. Numerical analysis is also performed; there are good matches of the simulation and experimental results.
Mode-Division-Multiplexing (MDM) of 9.4-Tbit/s OFDM Signals on Silicon-on-Insulator (SOI) Platform
(2019-01-01)
Chen, Guan-Hong
;
Chow, Chi-Wai
;
Yeh, Chien-Hung
;
Peng, Ching-Wei
;
Guo, Pin-Cheng
Silicon photonic (SiPh) technology applied for optical communication systems and network-on-chips have attracted many attentions. We propose and demonstrate the use of a 4 x 4 mode-division-multiplexing (MDM) - multiplexer (MUX) and demultiplexer (DEMUX) to provide 200-Gbit/s orthogonal-frequency-division-multiplexing (OFDM) per wavelength signal transmission. The MDM MUX and DEMUX are implemented by asymmetric directional couplers (ADCs), which are constructed by an access waveguide for the transmission of fundamental mode; and the bus waveguide for the transmission of higher order modes. When phase matching condition is satisfied between the access waveguide and bus waveguide, mode conversion can be achieved. Here, 47 wavelengths are successfully mode multiplexed and de-multiplexed achieving a total transmission capacity 9.4 Tbit/s. Numerically study and analysis of the SiPh MDM MUX/DEMUX are presented, and the experimental evaluations are performed.
Tricolor visible-light laser diodes based visible light communication operated at 40.665 Gbit/s and 2 m free-space transmission
(2019-09-02)
Wei, Liang-Yu
;
Chow, Chi-Wai
;
Chen, Guan-Hong
;
Liu, Yang
;
Yeh, Chien-Hung
Visible light communication (VLC) can provide a dedicated, secure, and high data rate wireless transmission link. It has gained considerable attentions recently, and is considered as one of the promising technologies for beyond 5G mobile and wireless communications. In this work, we demonstrate a VLC system with a recorded data rate of 40.665 Gbit/s using tricolor red, green and blue (RGB) laser diodes (LDs) and polarization multiplexing. 2 m free-space transmission distance is achieved. The implementation of bit-loading, power-loading, and polarization multiplexing are discussed. Experimental bit-errorratio (BER) results show that each of the 6 polarization and wavelength de-multiplexed channels can achieve the forward-error-correction (FEC) requirement. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement