Browsing by Author "Lu, I-Cheng"

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106-fJ/(bit.km) 2-km OFDM OM4 MMF Transmissions for Energy Efficient Optical Interconnects
(2013)
Lu, I-Cheng
;
Chen, Hsing-Yu
;
Wei, Chia-Chien
;
Shi, Jin-Wei
;
Tsai, Sheng-Fan
Employing high-performance 850-nm VCSELs with oxide-relief and Zn-diffusion structures, we demonstrate 17.8-Gbps 2-km OM4 fiber transmissions. Meanwhile, ultra-low EDDR of 106 fJ/(bit km) with bias current as low as 1.9 mA is achieved.
20-Gbps WDM-PON Transmissions Employing Weak-resonant-cavity FPLD with OFDM and SC-FDE Modulation Formats
(2013-01-01)
Lu, I-Cheng
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Chen, Hsing-Yu
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Wei, Chia-Chien
;
Chi, Yu-Chieh
;
Lee, Yi-Cheng
We experimentally demonstrate a superior performance of 20-Gbps OFDM/SC-FDE transmission over 20-km WDM-PONs, using a channelized weak-resonant-cavity FPLD with a modulation bandwidth of only 1.25 GHz by using injection-locking, direct detection and adopting the power-loading algorithm.
20-Gbps WDM-PON transmissions employing weak-resonant-cavity FPLD with OFDM and SC-FDE modulation formats
(2013-04-08)
Lu, I-Cheng
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Wei, Chia-Chien
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Jiang, Wen-Jr
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Chen, Hsing-Yu
;
Chi, Yu-Chieh
Using a colorless weak-resonant-cavity (WRC) FPLD injected by a centralized light source, we have experimentally demonstrated a superior performance of 20-Gbps uplink transmission in a WDM-PON. Even though the typical modulation bandwidth of a WRC-FPLD is only similar to 1.25 GHz, using spectrally-efficient 32-QAM OFDM or SC-FDE modulation, 20-Gbps uplink signals can achieve the FEC limit after 25-km dispersion-uncompensated single-mode fiber transmission. Because of the advantage of lower PAPR, the SC-FDE signals outperform the OFDM signals with the fixed 32-QAM format in the proposed system; moreover, SC-FDE scheme can be another promising candidate for uplinks in WDM-PONs, for its simplification to ONUs. The signal at the mode of 1560.7 nm shows similar quality with the signal at the modes of 1545.3 nm and 1574.7 nm, the WRC-FPLD, accordingly, has wide injection wavelength range from at least 1545.3 nm to 1574.7 nm. With the mode spacing of 0.55 nm, consequently, we have demonstrated the applicability of the colorless WRC-FPLD on supporting up to 36 channels in the WDM-PON. (C) 2013 Optical Society of America
32-dB Loss Budget High-Capacity OFDM Long-Reach PON over 60-km Transmission without Optical Amplifier
(2014-01-01)
Wei, Chia-Chien
;
Chen, Hsing-Yu
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Chu, Hsuan-Hao
;
Chen, Yu-Chao
;
Song, Cih-Yuan
For the first time, 33-Gbps 60-km OFDM transmission is demonstrated to show 32-dB loss budget without inline and pre-amplifier. Employing 10-GHz EAM and PIN, the long-reach PON can economically support 32 ONUs with >1-Gbps/ONU capacity.
400-Gb/s Transmission Over 10-km SSMF Using Discrete Multitone and 1.3-mu m EMLs
(2014-08-15)
Chan, Trevor
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Lu, I-Cheng
;
Chen, Jyehong
;
Way, Winston I.
;
光電工程學系
We experimentally demonstrated 400-Gb/s transmission over 10-km standard single-mode using discrete multi-tone (DMT) and four 1.3-mu m local-area-network wavelength-division-multiplexed externally modulated lasers. A reasonably good system margin has been obtained. We have also investigated the fundamental limitations of using semiconductor optical amplifiers for DMT-based systems.
50-Gbps 100-km EAM-based OFDM-IMDD Transmission Employing Novel SSII Cancellation
(2014-01-01)
Chen, Hsing-Yu
;
Wei, Chia-Chien
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Chen, Yu-Chao
;
Chu, Hsuan-Hao
;
Song, Cih-Yuan
We build a new SSII cancellation technique to compensate both modulator nonlinearity and dispersion-induced nonlinear distortion. Employing the SSII cancellation to optimize EAM operation, superior 50-Gbps EAM-based OFDM-IMDD transmission over 100-km SSMF is successfully demonstrated.
6.36 Gbit/s RGB LED-based WDM MIMO Visible Light Communication System Employing OFDM Modulation
(2017-01-01)
Lu, I-Cheng
;
Lai, Chih-Han
;
Yeh, Chien-Hung
;
Chen, Jyehong
;
光電工程學系
An aggregate data rate of 6.36 Gbit/s of RGB 2X2 MIMO VLC system is demonstrated for the proof-of-concept. Moreover, the corresponding VLC rates under the free-space transmissions of 1 to 3 m are also analyzed.
A 200-Gbps OFDM Long-Reach PON over 60-km Transmission without Inline and Pre-Amplifier
(2015)
Chen, Hsing-Yu
;
Wei, Chia-Chien
;
Lin, Che-Yu
;
Chen, Li-Wei
;
Lu, I-Cheng
200-Gbps 60-km OFDM transmission in a 4-channel WDM system is demonstrated with 29-dB loss budget per channel without inline and pre-amplifier. Employing 10-GHz EAM and PIN, the LR-PON can support 64 ONUS with >2.5-Gbps/ONU capacity.
Adaptive filtering for white-light LED visible light communication
(2017-01)
Hsu, Chin-Wei
;
Chen, Guan-Hong
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Wei, Liang-Yu
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Chow, Chi-Wai
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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)
An EAM-based 50-Gbps 60-km OFDM System with 29-dB Loss Budget Enabled by SSII Cancellation or Volterra Filter
(2014)
Chen, Hsing-Yu
;
Wei, Chia-Chien
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Chu, Hsuan-Hao
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Chen, Yu-Chao
;
Lu, I-Cheng
Different nonlinear compensation techniques are compared for the first time, and 57.5-Gbps 60-km IMDD OFDM transmission is achieved. The loss budget of 32 or 29 dB is demonstrated to support 40-Gbps 64-ONUs or 50-Gbps 32-ONUs over 60-km LR-PON without amplifiers.
Analysis of Nonlinear Distortion and SSII Cancellation in EAM-Based IMDD OFDM Transmission
(2015-07-15)
Wei, Chia-Chien
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Cheng, Hsuan-Lin
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Chen, Hsing-Yu
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Chen, Yu-Chao
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Chu, Hsuan-Hao
In terms of second-order nonlinearity, nonlinear distortion in an EAM-based IMDD OFDM system is deterministically modeled as subcarrier-to-subcarrier intermixing interference ( SSII), such that DSP-based nonlinear compensation can be provided by decision-aided SSII cancellation at the receiver. The effectiveness of SSII cancellation heavily relies on the accuracy of SSII calculation, which is determined mainly by the modulation model adopted. This study made comprehensive comparisons of three small-signal models (constant-chirp, dynamic-chirp, and nonlinear-E/O models). We then combined theory and experiment results to examine the characteristics of SSII estimation and cancellation using various models, such as SSII spectra, regression coefficients, and correlation coefficients between the SSII and the total received errors, as well as the relationship between improvements in performance and the correlation coefficient. The nonlinear-E/O model is the most comprehensive, and as a result presents the flattest regression coefficient and highest correlation coefficient, which results in the most pronounced improvement in performance.
Coherently wavelength injection-locking a 600-mu m long cavity colorless laser diode for 16-QAM OFDM at 12 Gbit/s over 25-km SMF
(2013-07-15)
Li, Yi-Cheng
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Chi, Yu-Chieh
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Cheng, Min-Chi
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Lu, I-Cheng
;
Chen, Jason
The coherent injection-locking and directly modulation of a long-cavity colorless laser diode with 1% end-facet reflectance and weak-resonant longitudinal modes is employed as an universal optical transmitter to demonstrated for optical 16-QAM OFDM transmission at 12 Gbit/s over 25 km in a DWDM-PON system. The optimized bias current of 30 mA (similar to 1.5Ith) with corresponding extinction ratio (ER) of 6 dB and the external injection power of -9 dBm is (are) required for such a wavelength-locked universal transmitter to carry the 16-QAM and 122-subcarrier formatted OFDM and data-stream. By increasing external injection-locking from. 9 dBm to 0 dBm, the peak-to-peak chirp of the OFDM data stream reduces from 7.7 to 5.4 GHz. The side mode suppression ratio (SMSR) of up to 50 dB is achieved with wider detuning range between -0.5 nm to 2.0 nm under an injection power of 0 dBm. By modulating such a colorless laser diode with an OFDM data stream of 122 subcarriers at a central carrier frequency of 1.5625 GHz and a total bandwidth of 3 GHz, the transmission data rate of up to 12 Gbit/s in standard single-mode fiber over 25 km is demonstrated to achieve an error vector magnitude (EVM) of 5.435%. Such a universal colorless DWDM-PON transmitter can deliver the optical OFDM data-stream at 12 Gbit/s QAM-OFDM data after 25-km transmission with a receiving power sensitivity of -7 dBm at BER of 3.6x10(-7) when pre-amplifying the OFDM data by 5 dB. (C) 2013 Optical Society of America
Demonstration of High Speed Imaging 3x3 MIMO-OFDM Visible Light Communication System
(2016-01-01)
Hsu, Chin-Wei
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Lu, I-Cheng
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Liu, Yen-Liang
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Yeh, Chien-Hung
;
Chow, Chi-Wai
We experimentally demonstrate the 3x3 imaging multiple-input multiple-output (MIMO) visible light communication (VLC) system, using orthogonal frequency division multiplexing (OFDM) modulation and bit-loading, a total data rate > 800-Mbit/s over 1-m transmission is achieved without using blue-filter.
EAM-based high-speed 100-km OFDM transmission featuring tolerant modulator operation enabled using SSII cancellation
(2014-06-16)
Chen, Hsing-Yu
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Wei, Chia-Chien
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Lu, I-Cheng
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Chen, Yu-Chao
;
Chu, Hsuan-Hao
In this study, a technique was developed to compensate for nonlinear distortion through cancelling subcarrier-to-subcarrier intermixing interference (SSII) in an electroabsorption modulator (EAM)-based orthogonal frequency-division multiplexing (OFDM) transmission system. The nonlinear distortion to be compensated for is induced by both EAM nonlinearity and fiber dispersion. Because an OFDM signal features an inherently high peak-to-average power ratio, a trade-off exists between the optical modulation index (OMI) and modulator nonlinearity. Therefore, the nonlinear distortion limits the operational tolerance of the bias voltage and the driving power to a small region. After applying the proposed SSII cancellation, the OMI of an OFDM signal was increased yielding only a small increment of nonlinear distortion, and the tolerance region of the operational conditions was also increased. By employing the proposed scheme, this study successfully demonstrates 50-Gbps OFDM transmission over 100-km dispersion-uncompensated single-mode fiber based on a single 10-GHz EAM. (C)2014 Optical Society of America
Energy Efficient 850 nm Vertical-Cavity Surface-Emitting Lasers with Extremely Low Driving-Current Density for > 40 Gbit/sec Error-Free Transmissions from RT to 85 degrees C
(2015)
Chi, Kai-Lun
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Jiang, Jia-Wei
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Yen, Jia-Liang
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Lu, I-Cheng
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Kuo, H. -C.
850nm VCSELs with record-low driving-current-density (8kA/cm(2)) small resistance (6012), wide-bandwidth (26GHz), and small energy-to-data-rate ratio (228fJ/bit; 3.5mA) for >41Gbit/sec error-free transmission over 100 (2) meter OM4 fiber at room-temperature (85 degrees C) have been demonstrated. (C) 2014 Optical Society of America
Frequency - and time-domain nonlinear distortion compensation in high-speed OFDM-IMDD LR-PON with high loss budget
(2017-03-06)
Chen, Hsing-Yu
;
Wei, Chia-Chien
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Lin, Che-Yu
;
Chen, Li-Wei
;
Lu, I-Cheng
This study compared two nonlinear distortion compensation techniques, SSII cancellation (in the frequency domain) and Volterra filtering (in the time domain), in a > 50-Gbps/lambda OFDM-IMDD LR-PON. Experiment results for SNR, BER, and data rate (based on a bit-loading algorithm) revealed that the performance of frequency-domain SSII cancellation is unaffected by power fading; however, it depends heavily on the precision of the mathematical model. Conversely, although time-domain Volterra filtering is affected by the faded waveform, adaptive-weighting provides flexibility in dealing with mixed nonlinear distortion, particularly that associated with the interplay between fiber dispersion and fiber nonlinearity. 4-channel WDM-OFDM and 3rd-order Volterra filtering were used to demonstrate the feasibility of the proposed scheme in a 200-Gbps IMDD system. Based on 10-GHz EAM and PIN, we achieved 200-Gbps transmission over a distance of 60 km with a loss budget of > 30 dB, while providing support for 128 ONUs at >1.6 Gbps/ONU without the need for an inline amplifier or pre-amplifier. (C) 2017 Optical Society of America
High Speed Imaging 3 x 3 MIMO Phosphor White-Light LED Based Visible Light Communication System
(2016-12-01)
Hsu, Chin-Wei
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Chow, Chi-Wai
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Lu, I-Cheng
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Liu, Yen-Liang
;
Yeh, Chien-Hung
The phosphor light-emitting diode (LED) has been widely used not only for indoor illumination but for the optical transmitter (Tx) as well in visible light communication (VLC). However, the transmission data rate is significantly limited by the modulation bandwidth of LED because of the low-speed response of phosphor. In order to enhance the data rate of the VLC system, we demonstrate a 3 x 3 imaging multiple-input multiple-output (MIMO) VLC system. Besides, the pre-equalizer circuit is used to extend the bandwidth of the LED Tx. Orthogonal frequency division multiplexing (OFDM) with bit-loading algorithm is used. By using the proposed scheme, the original 1 MHz bandwidth commercially available phosphor white light LED can achieve 1 Gbps data rate over 1-m free-space transmission distance.
High-Capacity and High-Loss-Budget OFDM Long-Reach PON Without an Optical Amplifier
(2015-01-01)
Chen, Hsing-Yu
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Wei, Chia-Chien
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Lu, I-Cheng
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Chu, Hsuan-Hao
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Chen, Yu-Chao
This work utilizes high launch power and the corresponding self-phase modulation (SPM) effect to combat dispersion-induced power fading and the insufficient loss budget of an intensity modulation and direct detection (IMDD) orthogonal frequency division multiplexing (OFDM) 60 km long-reach passive optical network (LR-PON). In addition, based on the proposed comprehensive transmission model, the subcarrier-to-subcarrier intermixing interference (SSII) cancellation scheme is applied to simultaneously eliminate the nonlinear distortions caused by the interplay among dispersion, the SPM effect, and the modulator-induced nonlinearity and chirp. Thanks to the high launch power and SSII cancellation, 40 and 50 Gbps 60 km OFDM transmission is successfully demonstrated to show 33 and 28 dB loss budgets, respectively, without an inline amplifier or preamplifier. Hence, by employing a 10 GHz electro-absorption modulator and PIN detector, the proposed LR-PON can economically support 64 or 32 optical network users with a capacity of 50 or 40 Gbps.
High-Speed 2x2 MIMO-OFDM Visible Light Communication Employing Phosphorescent LED
(2016)
Lu, I-Cheng
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Liu, Yen-Liang
;
Lai, Chih-Han
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光電工程學系
;
Department of Photonics
We experimentally demonstrated a 2x2 multiple-input multiple-output (MIMO) visible light communication (VLC) system using commercial phosphorescent white light emitting diodes (LEDs) and low-cost PIN photodiodes (PDs). Additionally, a pre-equalizer was used to extend the available modulation bandwidth up to 100 MHz. Using spectral-efficient orthogonal frequency division multiplexing (OFDM) modulation with bit-loading algorithm, we successfully achieved high-speed VLC transmission at > 1 Gbit/s over a free-space link of 0.6 m.