Showing papers by "Hung-Chang Chien published in 2012"
TL;DR: In this paper, the phase and amplitude relationship between RF driving signals of two cascaded phase modulators and the impact of EDFA gain were analyzed for a multi-terabit optical OFDM superchannel transmission.
Abstract: The generation of coherent and frequency-locked optical multi-carriers by using cascaded phase modulators and recirculating frequency shifter (RFS) based on an erbium doped fiber amplifier (EDFA) loop has been investigated theoretically and experimentally for a multi-terabit optical orthogonal frequency division multiplexing (OFDM) superchannel transmission. The phase and amplitude relationship between RF driving signals of two cascaded phase modulators and the impact of EDFA gain are analyzed. Experimental results are in good agreement with the theoretical analysis. The 112 coherent and frequency-locked subcarriers obtained after tilt filtering exhibit a tone-to-noise ratio of larger than 26 dB, a power fluctuation of less than 5 dB, and a frequency spacing of 25 GHz giving a 22.6 nm-wide optical OFDM signal spectrum. By using this method, we have successfully generated a 10-Tbit/s (112 × 100 Gbit/s) single optical OFDM polarization-division-multiplexing QPSK (PDM-QPSK) superchannel with an optical signal to noise ratio per OFDM subchannel greater than 20 dB at 0.1 nm bandwidth, and it has been transmitted over a 640-km SMF-28 and EDFA-only link with BER less than 2 × 10-3.
60 citations
TL;DR: In this paper, the authors focused on terabit superchannel transmission with enhanced network reach by using an emerging noise-suppressed Nyquist wavelength division multiplexing (NS-N-WDM) technique for polarization multiple-xing quadrature phase shift keying subchannels at different symbol rate to subchannel spacing ratios up to 1.28.
Abstract: This paper focuses on terabit superchannel transmission with enhanced network reach by using an emerging noise-suppressed Nyquist wavelength division multiplexing (NS-N-WDM) technique for polarization multiplexing quadrature phase shift keying subchannels at different symbol rate to subchannel spacing ratios up to 1.28, and for the first time, it was compared experimentally with the transmission capability of no-guard-interval coherent optical orthogonal frequency division multiplexing (NGI-CO-OFDM) on the same testbed. At 2 × 10-3 bit error ratio, the maximum reachable distance is 3200 and 2800 km SMF-28 with erbium-doped-fiber-amplifier-only amplification for NGI-CO-OFDM and NS-N-WDM terabit superchannels, respectively, at 100 Gb/s/ch. For 11 ntn112 and 11 × 128 Gb/s/ch NS-N-WDM transmission under assumption of different coding gain with hard-decision and soft-decision forward error correction, their maximum achievable distance was found to be equivalent, which are 2100 and 2170 km, respectively, both were achieved by using digital noise filtering and 1-bit maximum likelihood sequence estimation at the receiver DSP. In addition, the back-to-back characteristics of NS-N-WDM superchannel such as analog-to-digital converter bandwidth requirement and its tolerance to unequal subchannel power were experimentally evaluated and studied.
49 citations
TL;DR: In this paper, the first field transmission of 8 × 216.8-Gb/s Nyquist-WDM signals is reported over 1750-km distance with 21.6dB average loss per span.
Abstract: Successful joint experiments with Deutsche Telecom (DT) on long-haul transmission of 100 G and beyond are demonstrated over standard single-mode fiber (SSMF) and inline erbium-doped fiber amplifier-only amplification. The transmission link consists of eight nodes and 950-km installed SSMF in DT's optical infrastructure with the addition of lab SSMF for extended optical reach. The first field transmission of 8 × 216.8-Gb/s Nyquist-WDM signals is reported over 1750-km distance with 21.6-dB average loss per span. Each channel modulated by a 54.2-Gbaud PDM-CSRZ-QPSK signal is on 50-GHz grid, achieving a net spectral efficiency (SE) of 4 bit/s/Hz. We also demonstrate mixed data-rate transmission coexisting with 1 T, 400 G, and 100 G channels. The 400 G uses four independent subcarriers modulated by 28-Gbaud PDM-QPSK signals, yielding the net SE of 4 bit/s/Hz while 13 optically generated subcarriers from single optical source are employed in 1 T channel with 25-Gbaud PDM-QPSK modulation. The 100 G signal uses real-time coherent PDM-QPSK transponder with 15% overhead of soft-decision forward-error correction. The digital postfilter and 1-bit maximum likelihood sequence estimation are introduced at the receiver DSP to suppress noise, linear crosstalk, and filtering effects. Our results show the future 400 G and 1 T channels utilizing the Nyquist wavelength division multiplexing technique can transmit long-haul distance with higher SE using the same QPSK format.
46 citations
TL;DR: In this article, a 7.284 Tb/s/ch signal was transmitted over 320 km conventional single mode fiber (SMF-28) with hybrid amplifier spans of 80 km.
Abstract: We have transmitted a 7×1.284 Tb/s/ch signal over 320-km conventional single mode fiber (SMF-28) with hybrid amplifier spans of 80 km. Each terabit superchannel comprises ten Nyquist wavelength division multiplexing polarization division multiplexing 64 quadrature amplitude modulation subchannels occupying 137.5 GHz, which gives a spectral-efficiency of 7.65 b/s/Hz per superchannel. The bit error ratio of all channels after transmission over 320 km is measured smaller than 2×10-2, the soft-decision forward error correction limit.
29 citations
TL;DR: In this paper, a 7×224 Gb/s/ch Nyquist wavelength-division-multiplexed signal over a 1600-km conventional singlemode fiber (SMF-28) with 80 km per span and an erbium-doped fiber amplifier-only amplification was transmitted.
Abstract: We have transmitted a 7×224 Gb/s/ch Nyquist wavelength-division-multiplexed signal over a 1600-km conventional single-mode fiber (SMF-28) with 80 km per span and an erbium-doped fiber amplifier-only amplification. Each channel on the 50-GHz grid is modulated using polarization-division-multiplexed quadrature-phase-shift-keying at 56 Gbaud giving a record spectral efficiency of 4 b/s/Hz. Both the post filter and the Viterbi maximum likelihood sequence detection are introduced into digital signal processing, to suppress the undesired noise, linear crosstalk enhancement, and filtering effects. The bit error ratio of all channels after transmission over a 1600-km SMF-28 is smaller than the forward error correction limit of 3.8×10-3.
27 citations
04 Mar 2012
TL;DR: In this paper, the authors achieved the first field transmission of 8×216.4 Gb/s Nyquist-WDM signals over 1750-km G.652 fiber consisting of 950km field-deployed and 800km lab fibers with 21.6dB average loss per span and EDFA-only amplification.
Abstract: We have achieved the first ever field transmission of 8×216.4 Gb/s Nyquist-WDM signals over 1750-km G.652 fiber consisting of 950km field-deployed and 800km lab fibers with 21.6-dB average loss per span and EDFA-only amplification. Each channel is 54.2-Gbaud (216.4-Gbit/s) PDM-CSRZ-QPSK signal on 50-GHz grid with a record spectral efficiency of 4b/s/Hz. The digital post filter and 1-bit MLSE are introduced at the receiver DSP to suppress noise, linear crosstalk and filtering effects.
20 citations
TL;DR: In this article, the authors proposed a vector signal transmission scheme for double-sideband with carrier-suppressed (DSB-CS) radio-over-flber system.
Abstract: We proposed a new vector signal transmission scheme for double-sideband with carrier-suppressed (DSB-CS) radio-over-flber system. The traditional single-stage DSB-CS scheme will induce signal phase distortion, and is therefore not suitable for vector signal delivery. However, by taking the advantage of the intrinsic local oscillator (LO) power feedthrough at a physical mixer, we found the phase information of the received vector signal would be preserved without introducing any hardware complexity to transmitter and receiver system setup. A feasibility demonstration of transmitting tri-band 16QAM-orthogonal frequency-division multiplexing signal carried by a DSB-CS optical mm-wave has been achieved with a received error vector machine value less than 14.8% after 100-km standard single-mode fiber and over 5-m wireless distance. In addition, the optimal value and dynamic range for the LO input power was investigated and experimentally measured.
13 citations
04 Mar 2012
TL;DR: In this paper, three-channel WDM transmission of 12.84-Tb/s/ch polarization division multiplexed (PDM) 64-QAM over 320-km SMF-28 with hybrid amplification spans was demonstrated.
Abstract: We demonstrate three-channel WDM transmission of 12.84-Tb/s/ch polarization division multiplexed (PDM) 64-QAM over 320-km SMF-28 with hybrid amplification spans. Each 10-Tb/s superchannel comprises one hundred Nyquist DWDM subchannels in 1275-GHz spectrum occupancy, yielding a spectral efficiency of 7.9 b/s/Hz. The BER of all channels after transmission over 320 km is measured smaller than 2×10-2, the third generation FEC limit.
12 citations
16 Sep 2012
TL;DR: In this article, a long-reach 400G transmission proposal based on quad-carrier PM-QPSK with a net spectral efficiency of 4 b/s/Hz was experimentally demonstrated.
Abstract: For the first time, a long-reach 400G transmission proposal based on quad-carrier PM-QPSK with a net spectral efficiency of 4 b/s/Hz was experimentally demonstrated. Under the assumption of narrowing100-GHz bandwidth after passing through multiple optical nodes, 512-Gb/s quad-carrier PM-QPSK signals were successfully delivered over 2400-km SMF-28 with EDFA-only amplification, and the worst-case BER received at edge channel was small than the soft-decision pre-FEC limit of 2×10-2.
9 citations
16 Sep 2012
TL;DR: Receiver-side digital filtering and low-complexity MLSE are introduced for the suppression of noise and linear crosstalk in PDM-QPSK channels.
Abstract: We have successfully transmitted 40×433.6-Gb/s PDM-QPSK channels at a record of 108.4-GBaud over 2800-km EDFA only SMF-28 link with a BER below 3.8×10-3. Receiver-side digital filtering and low-complexity MLSE are introduced for the suppression of noise and linear crosstalk.
8 citations
09 Jul 2012
TL;DR: In this paper, the authors review experimental demonstrations on optical mm-wave generation and modulation technologies for high-speed radio-over-fiber communication, including the feasibility studies on delivering vector signals over DSB-SC optical mmWave, duobinary modulation, and Fabry-Perot subharmonic mmWave generator.
Abstract: We review recent experimental demonstrations on optical mm-wave generation and modulation technologies for high-speed radio-over-fiber communication, including the feasibility studies on delivering vector signals over DSB-SC optical mm-wave, duobinary modulation, and Fabry-Perot subharmonic mm-wave generator.
04 Mar 2012
TL;DR: A novel self-mixing duobinary RF receiver structure for 60-GHz radio-over-fiber systems is proposed, which simultaneously downconverts and decodes RFduobinary signals at Nyquist limit.
Abstract: We propose a novel self-mixing duobinary RF receiver structure for 60-GHz radio-over-fiber systems, which simultaneously downconverts and decodes RF duobinary signals at Nyquist limit. Error-free transmission at 4Gb/s over 25-km SMF-28 and 4-ft wireless is demonstrated.
09 Jul 2012
Abstract: A novel duobinary RF receiver is proposed and demonstrated based on RF envelope detection for millimeter-wave radio-over-fiber systems. Robust RF downconvertion and duobinary decoding are achieved simultaneously at an RF envelope detector. Duobinary signal delivery over wired and wireless link in coherent single-sideband optical millimeter-wave systems is demonstrated for the first time.
04 Mar 2012
TL;DR: In this article, a filtering-tolerant offset RZ pulse shape for 128Gb/s PDM-QPSK was proposed for the first time, and the authors showed that 0.8 and 0.2dB OSNR penalties at SD pre-FEC BER limit were experimentally and numerically demonstrated.
Abstract: A filtering-tolerant, offset RZ pulse shape for 128Gb/s PDM-QPSK was proposed for the first time. On a 25GHz grid, 0.8 and 0.2dB OSNR penalties at SD pre-FEC BER limit were experimentally and numerically demonstrated, respectively.
04 Mar 2012
TL;DR: In this article, the fundamental limits of an optical processing technique that enables instantaneous demultiplexing of orthogonal-wavelength-division multiplexing in terabit optical networking systems without requiring conventional guard-band were investigated.
Abstract: We investigated the fundamental limits of an optical processing technique that enables instantaneous demultiplexing of orthogonal-wavelength-division-multiplexing in terabit optical networking systems without requiring conventional guard-band.