An extended interaction oscillator （EIO） generating 120 GHz wave in sub-terahertz waves is studied by using the three-dimensional electromagnetic simulation software CST and PIC codes. A rectangular reentrant couple...An extended interaction oscillator （EIO） generating 120 GHz wave in sub-terahertz waves is studied by using the three-dimensional electromagnetic simulation software CST and PIC codes. A rectangular reentrant coupled-cavity is proposed as the slow-wave structure of EIO. By CST, the circuit parameters including frequency-phase dispersion, interaction impedance and characteristic impedance are simulated and calculated. The operation mode of EIO is chosen very close to the point where βL = 2π with corresponding frequency 120 GHz, the beam voltage 12 kV and the dimensions of the cavity with the period 0.5mm, the height 3mm and the width 1.4mm. Simulation results of beam-wave interaction by PIC show that the exciting frequency is 120.85 GHz and output peak power 465 W with 12-period coupled-cavity with the perveance 0.17 μP. Simulation results indicate that the EIO has very wide range of the operation voltage.展开更多
A backward wave amplifier（BWA） in a terahertz regime with a novel slow-wave structure（SWS） composed of multi parallel grating pins inside a rectangular waveguide is analyzed. The multi-pin rectangular waveguide SW...A backward wave amplifier（BWA） in a terahertz regime with a novel slow-wave structure（SWS） composed of multi parallel grating pins inside a rectangular waveguide is analyzed. The multi-pin rectangular waveguide SWS possesses good performance and is compatible with micro-fabrication technologies. The dispersion and interaction impedance of the multipin SWS are presented. The stopbands of the modes cling together in a Brillouim zone. The SWS has a high interaction impedance that is suitable for the interaction of multi cylindrical beams. The design, which is based on three parallel pins supporting the wave–beam interaction with four cylindrical beams, is verified by three-dimensional particle-in-cell simulations. A BWA with the central frequency at 340 GHz is demonstrated, and the output power is more than 100 mW.A tuning frequency range of 15 GHz（333–348 GHz） is obtained with a gain of more than 20 dB.展开更多
This paper considers the frequency-quadrupling three-cavity gyroklystrons with successive frequency-doubling in each cavity.The cavities of 225 GHz frequency-quadrupling gyroklystron are designed with the scattering m...This paper considers the frequency-quadrupling three-cavity gyroklystrons with successive frequency-doubling in each cavity.The cavities of 225 GHz frequency-quadrupling gyroklystron are designed with the scattering matrices method and the possible operating mode are discussed.With the point-gap theory,the starting currents of the possible operating modes and the potential parasitic modes in the output cavity are calculated. The optimal operating mode is proposed under consideration of the mode competition and the power capacity of the cavity.展开更多
This paper analyses a three-cavity frequency-quadrupling terahertz gyroklystron with successive frequency-doubling in each cavity with self-consistent nonlinear theory. The beam-wave interaction efficiency and the ele...This paper analyses a three-cavity frequency-quadrupling terahertz gyroklystron with successive frequency-doubling in each cavity with self-consistent nonlinear theory. The beam-wave interaction efficiency and the electron bunching process are studied. The variation of output efficiency with the length of drift tubes and output power and the variation of Ohmic loss with the length of output cavity are considered. Numerical simulations predict an optimal output efficiency of 1.8%, a power output of more than 2 kW and a gain of 33 dB after taking into account Ohmic losses when the frequency-quadrupling gyroklystron, driven by a 40-kV, 3-A electron beam and 1 Watt input power, operates at 225 CHz.展开更多
To develop 200 GHz electron cyclotron maser(ECM)in University of Electronic Science and Technology of China,a magnetron injection gun(MIG)with 60 kV/5 A has been designed.The behavior of the designed magnetron injecti...To develop 200 GHz electron cyclotron maser(ECM)in University of Electronic Science and Technology of China,a magnetron injection gun(MIG)with 60 kV/5 A has been designed.The behavior of the designed magnetron injection gun with variations of relevant parameters is given in detail by means of computer simulations.The preliminary and operation parameters of the gun are reported.The optimization by using the EGUN code shows that the ratio of the perpendicular velocity to the parallel velocity of the electron beam is 1.63,and the perpendicular and parallel velocities spread are 2.62%and 6.63%,respectively.展开更多
基金supported by the National Natural Science Foundation of China (Grant No 10676110)the National Basic Research Program of China (Grant No 2007CB310401)
文摘An extended interaction oscillator （EIO） generating 120 GHz wave in sub-terahertz waves is studied by using the three-dimensional electromagnetic simulation software CST and PIC codes. A rectangular reentrant coupled-cavity is proposed as the slow-wave structure of EIO. By CST, the circuit parameters including frequency-phase dispersion, interaction impedance and characteristic impedance are simulated and calculated. The operation mode of EIO is chosen very close to the point where βL = 2π with corresponding frequency 120 GHz, the beam voltage 12 kV and the dimensions of the cavity with the period 0.5mm, the height 3mm and the width 1.4mm. Simulation results of beam-wave interaction by PIC show that the exciting frequency is 120.85 GHz and output peak power 465 W with 12-period coupled-cavity with the perveance 0.17 μP. Simulation results indicate that the EIO has very wide range of the operation voltage.
基金Project supported by the National Basic Research Program of China(Grant No.2014CB339801)the National High Technology Research and Development Program of China(Grant No.G060104012AA8122007B)
文摘A backward wave amplifier（BWA） in a terahertz regime with a novel slow-wave structure（SWS） composed of multi parallel grating pins inside a rectangular waveguide is analyzed. The multi-pin rectangular waveguide SWS possesses good performance and is compatible with micro-fabrication technologies. The dispersion and interaction impedance of the multipin SWS are presented. The stopbands of the modes cling together in a Brillouim zone. The SWS has a high interaction impedance that is suitable for the interaction of multi cylindrical beams. The design, which is based on three parallel pins supporting the wave–beam interaction with four cylindrical beams, is verified by three-dimensional particle-in-cell simulations. A BWA with the central frequency at 340 GHz is demonstrated, and the output power is more than 100 mW.A tuning frequency range of 15 GHz（333–348 GHz） is obtained with a gain of more than 20 dB.
基金Project supported by National Natural Science Foundation of China (Grant No 10676110)National High Technology Research and Development Program of China (Grant No 2007BC310401)
文摘This paper considers the frequency-quadrupling three-cavity gyroklystrons with successive frequency-doubling in each cavity.The cavities of 225 GHz frequency-quadrupling gyroklystron are designed with the scattering matrices method and the possible operating mode are discussed.With the point-gap theory,the starting currents of the possible operating modes and the potential parasitic modes in the output cavity are calculated. The optimal operating mode is proposed under consideration of the mode competition and the power capacity of the cavity.
基金Project supported by National Natural Science Foundation of China (Grant No 10676110)973 Program of China (Grant No2007CB310401)
文摘This paper analyses a three-cavity frequency-quadrupling terahertz gyroklystron with successive frequency-doubling in each cavity with self-consistent nonlinear theory. The beam-wave interaction efficiency and the electron bunching process are studied. The variation of output efficiency with the length of drift tubes and output power and the variation of Ohmic loss with the length of output cavity are considered. Numerical simulations predict an optimal output efficiency of 1.8%, a power output of more than 2 kW and a gain of 33 dB after taking into account Ohmic losses when the frequency-quadrupling gyroklystron, driven by a 40-kV, 3-A electron beam and 1 Watt input power, operates at 225 CHz.
基金supported by the Major State Basic Research Development Program of China (No.2007CB310401)the National Natural Science Foundation of China (Grant No.10676110).
文摘To develop 200 GHz electron cyclotron maser(ECM)in University of Electronic Science and Technology of China,a magnetron injection gun(MIG)with 60 kV/5 A has been designed.The behavior of the designed magnetron injection gun with variations of relevant parameters is given in detail by means of computer simulations.The preliminary and operation parameters of the gun are reported.The optimization by using the EGUN code shows that the ratio of the perpendicular velocity to the parallel velocity of the electron beam is 1.63,and the perpendicular and parallel velocities spread are 2.62%and 6.63%,respectively.
