A novel architecture for wavelength-division-multiplexing passive optical network （WDM-PON） with centralized light-wave is proposed and demonstrated. At the optical line terminal （OLT） session of this architecture...A novel architecture for wavelength-division-multiplexing passive optical network （WDM-PON） with centralized light-wave is proposed and demonstrated. At the optical line terminal （OLT） session of this architecture, optical differential quadrature phase shift keying （DQPSK） modulated signal with constant-intensity at 10 Gbit/s is utilized for downstream transmission. At the optical network unit （ONU）, part of the downstream optical power is remodulated with on-off keying （OOK） intensity modulation at 10 Gbit/s for upstream without additional laser. Simulation results show that the power penalties of the downstream for 20 km single-mode fiber （SMF） transmission and multi-channels are negligible. While for the upstream, the power penalties are obvious. The simulation results and analysis also reflect that by reducing the launch power of DQPSK transmitters, power penalties can be reduced, although the transmission distance is limited.展开更多
In this paper, a scheme for generating sinc-shaped optical Nyquist pulses based on external modulation is proposed. First, five flat optical frequency comb(OFC) lines are generated by a dual-parallel Mach–Zehnder mod...In this paper, a scheme for generating sinc-shaped optical Nyquist pulses based on external modulation is proposed. First, five flat optical frequency comb(OFC) lines are generated by a dual-parallel Mach–Zehnder modulator(DP-MZM) for optical carrier phase cancellation interference. Then, the phase-locked OFC is split into two paths, one of which is transmitted to a single-drive Mach–Zehnder modulator(SD-MZM) for the modulation of the even-order side-band suppression, and the other is used to remodulate the signal in order to obtain equally spaced comb lines. Eventually, equal frequency spaced phase-locked 15-line OFCs are generated and extremely narrow over-zero width Nyquist pulses are realized at 2.5 GHz, 5 GHz, 10 GHz and 20 GHz. The root-mean-square error(RMSE) is calculated for the generated Nyquist pulses which enables the verification of the signal quality.展开更多
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 remodulat...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.展开更多
A simple and cost-effective remodulation scheme using a two-section reflective semiconductor optical amplifier （RSOA） is proposed for a colorless optical network unit （ONU）. Under proper injection currents, the fr...A simple and cost-effective remodulation scheme using a two-section reflective semiconductor optical amplifier （RSOA） is proposed for a colorless optical network unit （ONU）. Under proper injection currents, the front section functions as a modulator to upload the upstream signal while the rear section serves as a data eraser for efficient suppression of the downstream data. The dependences of the upstream transmission performance on the lengths and driven currents of the RSOA, the injection optical power and extinction ratio of the downstream are investigated. By optimizing these parameters, the downstream data can be more completely suppressed and the upstream transmission performance can be greatly improved.展开更多
基金supported by National Basic Research Program of China (2010CB328300)the National Natural Science Foundation of China (60677004,60977046,60702049)+2 种基金the Hi-Tech Research and Development Program of China (2009AA01Z220)the Teaching and Scientific Research Foundation for the Returned Overseas Chinese Scholars (State Education Ministry)the Program for New Century Excellent Talents in University of China (NECT-07-0111)
文摘A novel architecture for wavelength-division-multiplexing passive optical network （WDM-PON） with centralized light-wave is proposed and demonstrated. At the optical line terminal （OLT） session of this architecture, optical differential quadrature phase shift keying （DQPSK） modulated signal with constant-intensity at 10 Gbit/s is utilized for downstream transmission. At the optical network unit （ONU）, part of the downstream optical power is remodulated with on-off keying （OOK） intensity modulation at 10 Gbit/s for upstream without additional laser. Simulation results show that the power penalties of the downstream for 20 km single-mode fiber （SMF） transmission and multi-channels are negligible. While for the upstream, the power penalties are obvious. The simulation results and analysis also reflect that by reducing the launch power of DQPSK transmitters, power penalties can be reduced, although the transmission distance is limited.
基金supported by the National Natural Science Foundation of China(No.U2241229)the Fundamental Research Funds for the Central Universities(No.CUC25QT15)。
文摘In this paper, a scheme for generating sinc-shaped optical Nyquist pulses based on external modulation is proposed. First, five flat optical frequency comb(OFC) lines are generated by a dual-parallel Mach–Zehnder modulator(DP-MZM) for optical carrier phase cancellation interference. Then, the phase-locked OFC is split into two paths, one of which is transmitted to a single-drive Mach–Zehnder modulator(SD-MZM) for the modulation of the even-order side-band suppression, and the other is used to remodulate the signal in order to obtain equally spaced comb lines. Eventually, equal frequency spaced phase-locked 15-line OFCs are generated and extremely narrow over-zero width Nyquist pulses are realized at 2.5 GHz, 5 GHz, 10 GHz and 20 GHz. The root-mean-square error(RMSE) is calculated for the generated Nyquist pulses which enables the verification of the signal quality.
基金Ministry of Science and Technology,Taiwan(MOST)(MOST-106-2221-E-009-105-MY3)Aim for the Top University PlanMinistry of Education(MOE),Taiwan,China
文摘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.
基金supported by the National High Technology Research and Development Program of China(No.2013A014401)the Specialized Research Fund for the Doctoral Program of Higher Education(No.20120142110064)
文摘A simple and cost-effective remodulation scheme using a two-section reflective semiconductor optical amplifier （RSOA） is proposed for a colorless optical network unit （ONU）. Under proper injection currents, the front section functions as a modulator to upload the upstream signal while the rear section serves as a data eraser for efficient suppression of the downstream data. The dependences of the upstream transmission performance on the lengths and driven currents of the RSOA, the injection optical power and extinction ratio of the downstream are investigated. By optimizing these parameters, the downstream data can be more completely suppressed and the upstream transmission performance can be greatly improved.
