A control model of gas supply system is introduced for ion source and an adaptive discrete-time control algorithm to regulate the hydrogen injection. A real-time feedback control system （RFCS） is designed to control...A control model of gas supply system is introduced for ion source and an adaptive discrete-time control algorithm to regulate the hydrogen injection. A real-time feedback control system （RFCS） is designed to control the gas supply for ion source based on the control model and the discrete-time control algorithm. The experimental results have proved that RFCS could regulate the gas supply smoothly, suppress the arc＇s abrupt over-current at the end of the ion source discharging, prolong the discharge pulse and stabilize the ion concentration. With RFCS, the ion source for neutral beam injection has reached its longest pulse with a length of 4.5 seconds in a stable status.展开更多
A new concept of inner-feedback-style traveling wave tube oscillator, which is based on a traveling-wave tube having a partial reflector located at near the junction between the slow-wave structure and the output coup...A new concept of inner-feedback-style traveling wave tube oscillator, which is based on a traveling-wave tube having a partial reflector located at near the junction between the slow-wave structure and the output coupler and a mechanical tuner connected to the input coupler, is proposed. Simulations by CHIPIC code show that the inner-feedback-style traveling wave tube oscillator having 100W of power, about 10% of electron efficiency and a tunable band of 73.35-73.91 GHz may be achieved. Compared with Backward Wave Oscillators (BWOs), the new devices have similar ability for tuning, and have much higher electron efficiency, suggesting much more potential as a Terahertz source.展开更多
A novel integrated quadrature voltage controlled oscillator （QVCO） with a feedback current source is presented in this paper. Benefiting from the current adjusting function of the feedback current source, the propos...A novel integrated quadrature voltage controlled oscillator （QVCO） with a feedback current source is presented in this paper. Benefiting from the current adjusting function of the feedback current source, the proposed QVCO exhibits a uniform phase noise over the entire tuning range. This QVCO is implemented in 65-nm CMOS technology. The measurement results show that it draws less than 3-mA average current from a 1.2-V supply and the phase noise is less than -110 dBc/Hz @IMHz offset over the entire tuning range. The fluctuation of phase noise @IMHz offset from the center frequency of 2.84-GHz to 3.27-GHz is less than 1 dBc/Hz, which validates the correctness of the proposed current source feedback technique.展开更多
基金National Natural Science Foundation of China(No.10575105)
文摘A control model of gas supply system is introduced for ion source and an adaptive discrete-time control algorithm to regulate the hydrogen injection. A real-time feedback control system （RFCS） is designed to control the gas supply for ion source based on the control model and the discrete-time control algorithm. The experimental results have proved that RFCS could regulate the gas supply smoothly, suppress the arc＇s abrupt over-current at the end of the ion source discharging, prolong the discharge pulse and stabilize the ion concentration. With RFCS, the ion source for neutral beam injection has reached its longest pulse with a length of 4.5 seconds in a stable status.
基金Supported by the National Natural Science Foundation of China (No. 61172016)
文摘A new concept of inner-feedback-style traveling wave tube oscillator, which is based on a traveling-wave tube having a partial reflector located at near the junction between the slow-wave structure and the output coupler and a mechanical tuner connected to the input coupler, is proposed. Simulations by CHIPIC code show that the inner-feedback-style traveling wave tube oscillator having 100W of power, about 10% of electron efficiency and a tunable band of 73.35-73.91 GHz may be achieved. Compared with Backward Wave Oscillators (BWOs), the new devices have similar ability for tuning, and have much higher electron efficiency, suggesting much more potential as a Terahertz source.
文摘A novel integrated quadrature voltage controlled oscillator （QVCO） with a feedback current source is presented in this paper. Benefiting from the current adjusting function of the feedback current source, the proposed QVCO exhibits a uniform phase noise over the entire tuning range. This QVCO is implemented in 65-nm CMOS technology. The measurement results show that it draws less than 3-mA average current from a 1.2-V supply and the phase noise is less than -110 dBc/Hz @IMHz offset over the entire tuning range. The fluctuation of phase noise @IMHz offset from the center frequency of 2.84-GHz to 3.27-GHz is less than 1 dBc/Hz, which validates the correctness of the proposed current source feedback technique.
