EAST （experimental advanced superconducting tokamak） fast control power supply is a high-capacity single-phase AC/DC/AC inverter power supply, which traces the displacement signal of plasma, and excites coils in a v...EAST （experimental advanced superconducting tokamak） fast control power supply is a high-capacity single-phase AC/DC/AC inverter power supply, which traces the displacement signal of plasma, and excites coils in a vacuum vessel to produce a magnetic field that realizes plasma stabilization. To meet the requirements of a large current and fast response, the multi- ple structure of the carrier phase-shift three-level inverter is presented, which realizes parallelled multi-inverters, raises the equivalent switching frequency of the inverters and improves the per- formance of output waves. In this work the design scheme is analyzed, and the output harmonic characteristic of parallel inverters is studied. The simulation and experimental results confirm that the scheme and control strategy is valid. The power supply system can supply a large current, and has a perfect performance on harmonic features as well as the ability of a fast response.展开更多
Three dispersion compensation schemes of an optical label switching transmission system were investigated, which employs 40 Gbit/s return zero differential phase-shift keying（RZ-DPSK） payload labeled with 2.5 Gbit/s...Three dispersion compensation schemes of an optical label switching transmission system were investigated, which employs 40 Gbit/s return zero differential phase-shift keying（RZ-DPSK） payload labeled with 2.5 Gbit/s on-off keying（OOK） signal based on the optical carrier suppression and separation（OCSS） techniq ue, In the system, proposed are the receiver sensi ti vity oS payload and label, achieving -- 32. 4 dBm and --38.5 dBm, respectively. Using the optimal dispersion compensation scheme, after transmitted over 160 km and 320 km SMF respectively, the label can be recovered without power penalty, while the payload can be recovered with less than 2 dB and 5 dB penalty, respectively.展开更多
An approach to generate high-speed and wideband frequency shift keying(FSK)signals based on carrier phase-shifted double sideband(CPS-DSB)modulation is proposed and experimentally validated.The core part of the scheme...An approach to generate high-speed and wideband frequency shift keying(FSK)signals based on carrier phase-shifted double sideband(CPS-DSB)modulation is proposed and experimentally validated.The core part of the scheme is a pair of cascaded polarization-sensitive LiNbO_(3) Mach–Zehnder modulators and phase modulators,whose polarization directions of the principal axes are mutually orthogonal to each other.A proof-of-concept experiment is carried out,where a 0.5 Gb/s FSK signal with the carrier frequencies of 4 and 8 GHz and a 1 Gb/s FSK signal with the carrier frequencies of 8 and 16 GHz are generated successfully.展开更多
基金supported by Key Project of National Ninth Five-Year Research Program of China[(1998)1303]
文摘EAST （experimental advanced superconducting tokamak） fast control power supply is a high-capacity single-phase AC/DC/AC inverter power supply, which traces the displacement signal of plasma, and excites coils in a vacuum vessel to produce a magnetic field that realizes plasma stabilization. To meet the requirements of a large current and fast response, the multi- ple structure of the carrier phase-shift three-level inverter is presented, which realizes parallelled multi-inverters, raises the equivalent switching frequency of the inverters and improves the per- formance of output waves. In this work the design scheme is analyzed, and the output harmonic characteristic of parallel inverters is studied. The simulation and experimental results confirm that the scheme and control strategy is valid. The power supply system can supply a large current, and has a perfect performance on harmonic features as well as the ability of a fast response.
基金National Natural Science Foundation of China(60677004)National High Technology"863"Research and Development Program of China(2007AA01Z260)+4 种基金Key Project of Chinese Ministry of Education(107011)Key Laboratory of Broadband Optical Fiber Transmission and Communication Networks(Ministry of Education)Teaching and Scientific Research Foundation for the Returned Overseas Chinese Scholars(State Education Ministry)the Corporative Building Project of Beijing Educational Committee(XK100130737)Program for New Century Excellent Talents in University of China( NECT-07-0111)
文摘Three dispersion compensation schemes of an optical label switching transmission system were investigated, which employs 40 Gbit/s return zero differential phase-shift keying（RZ-DPSK） payload labeled with 2.5 Gbit/s on-off keying（OOK） signal based on the optical carrier suppression and separation（OCSS） techniq ue, In the system, proposed are the receiver sensi ti vity oS payload and label, achieving -- 32. 4 dBm and --38.5 dBm, respectively. Using the optimal dispersion compensation scheme, after transmitted over 160 km and 320 km SMF respectively, the label can be recovered without power penalty, while the payload can be recovered with less than 2 dB and 5 dB penalty, respectively.
基金supported by the National Natural Science Foundation of China(Nos.U2006217,61775015,61801017,and 61827818)。
文摘An approach to generate high-speed and wideband frequency shift keying(FSK)signals based on carrier phase-shifted double sideband(CPS-DSB)modulation is proposed and experimentally validated.The core part of the scheme is a pair of cascaded polarization-sensitive LiNbO_(3) Mach–Zehnder modulators and phase modulators,whose polarization directions of the principal axes are mutually orthogonal to each other.A proof-of-concept experiment is carried out,where a 0.5 Gb/s FSK signal with the carrier frequencies of 4 and 8 GHz and a 1 Gb/s FSK signal with the carrier frequencies of 8 and 16 GHz are generated successfully.
