Aiming at harsh environment of cluster bombs center tube explosion dispersion and difficulties in installation of traditional test systems,a storage test system based on 16-bit ultra-low power microcontroller MSP430 i...Aiming at harsh environment of cluster bombs center tube explosion dispersion and difficulties in installation of traditional test systems,a storage test system based on 16-bit ultra-low power microcontroller MSP430 is designed in order to acquire gas pressure during cluster bombs dispersion.To meet the requirement of low power consumption,the working states of system＇s modules during data acquisition are elaborated and the equation to calculate the gas pressure change during cylindrical center tube opening the hatch is deduced.The field test is conducted and good test results are obtained.展开更多
An all-metal slow-wave structure, coaxial-radial line, which is suitable for application in broadband high power traveling wave tube (TWT) and relativistic TWT as a RF system is introduced. Making use of the field mat...An all-metal slow-wave structure, coaxial-radial line, which is suitable for application in broadband high power traveling wave tube (TWT) and relativistic TWT as a RF system is introduced. Making use of the field matching method and variational method together with the orthogonality of the Bessel function and the Floquet Theroem for the periodic system, the dispersion characteristic expression is derived. This equation is more rigorous than that of precious reports.展开更多
This paper presents a theory on accurately analysing the dispersion relation and the interaction impedance of electromagnetic waves propagating through a helical groove waveguide with arbitrary groove shape, in which ...This paper presents a theory on accurately analysing the dispersion relation and the interaction impedance of electromagnetic waves propagating through a helical groove waveguide with arbitrary groove shape, in which the complex groove profile is synthesized by a series of rectangular steps. By introducing the influence of high-order evanescent modes on the connection of any two neighbouring steps by an equivalent susceptance under a modified admittance matching condition, the assumption of the neglecting discontinuity capacitance in previously published analysis is avoided, and the accurate dispersion equation is obtained by means of a combination of field-matching method and admittancematching technique. The validity of this theory is proved by comparison between the measurements and the numerical calculations for two kinds of helical groove waveguides with different groove shapes.展开更多
An open-styled dielectric-lined azimuthMly periodic circular waveguide （ODLAP-CW） for a millimeter-wave traveling-wave tube （TWT） is proposed, which is a modified form of a dielectric-lined azimuthally periodic ci...An open-styled dielectric-lined azimuthMly periodic circular waveguide （ODLAP-CW） for a millimeter-wave traveling-wave tube （TWT） is proposed, which is a modified form of a dielectric-lined azimuthally periodic circular waveguide （DLAP-CW）. The slow-wave characteristics of the open-styled DLAP-CW are studied by using the spatial harmonics method, which includes normalized phase velocity and interaction impedance. The complicated dispersion equations are numerically solved with MATLAB and the results are in good agreement with the simulation results obtained from HFSS. The influence of structural parameters on the RF properties is investigated based on our theory. The numerical results show that the optimal thickness of the metal rod can increase the interaction impedance, with the dielectric constant held fixed. Finally, the slow-wave characteristics and transmission properties of an open-styled structure are compared with those of the DLAP-CW. The results validate that the mode competition is eliminated in the improved structure with only a slight influence on the dispersion characteristics, which may significantly improve the stability of an open-styled DLAP-CW-based TWT, and the interaction efficiency is also improved.展开更多
设计了一个基于交错双光栅的双路并联慢波结构,该结构采用两注电子及均匀恒磁场聚焦系统,具有平面二维结构。对该慢波结构的色散等冷测特性进行了详细研究,采用功分器和传输变换结构构成高频互作用电路,输出口为WR-2.8标准波导口,在305 ...设计了一个基于交错双光栅的双路并联慢波结构,该结构采用两注电子及均匀恒磁场聚焦系统,具有平面二维结构。对该慢波结构的色散等冷测特性进行了详细研究,采用功分器和传输变换结构构成高频互作用电路,输出口为WR-2.8标准波导口,在305 GHz^335 GHz获得较好的传输特性,反射系数S11<-15 d B,传输系数S21>-4.4 d B。利用三维粒子模拟计算的方法,分析比较了单路及双路行波管放大特性。在电流密度53.57 A/cm2情况下增益达到14.586 d B,是一种极具发展潜力的太赫兹器件。展开更多
文摘Aiming at harsh environment of cluster bombs center tube explosion dispersion and difficulties in installation of traditional test systems,a storage test system based on 16-bit ultra-low power microcontroller MSP430 is designed in order to acquire gas pressure during cluster bombs dispersion.To meet the requirement of low power consumption,the working states of system＇s modules during data acquisition are elaborated and the equation to calculate the gas pressure change during cylindrical center tube opening the hatch is deduced.The field test is conducted and good test results are obtained.
基金Supported by the Fund of National Key Laboratory (No.51440020101DZ7604)
文摘An all-metal slow-wave structure, coaxial-radial line, which is suitable for application in broadband high power traveling wave tube (TWT) and relativistic TWT as a RF system is introduced. Making use of the field matching method and variational method together with the orthogonality of the Bessel function and the Floquet Theroem for the periodic system, the dispersion characteristic expression is derived. This equation is more rigorous than that of precious reports.
基金Project supported in part by the National Natural Science Foundation of China （Grant Nos 60401005 and 60532010） and the Fok Ying Tung Education Foundation（Grant No 91063）.
文摘This paper presents a theory on accurately analysing the dispersion relation and the interaction impedance of electromagnetic waves propagating through a helical groove waveguide with arbitrary groove shape, in which the complex groove profile is synthesized by a series of rectangular steps. By introducing the influence of high-order evanescent modes on the connection of any two neighbouring steps by an equivalent susceptance under a modified admittance matching condition, the assumption of the neglecting discontinuity capacitance in previously published analysis is avoided, and the accurate dispersion equation is obtained by means of a combination of field-matching method and admittancematching technique. The validity of this theory is proved by comparison between the measurements and the numerical calculations for two kinds of helical groove waveguides with different groove shapes.
基金supported by the National Natural Science Foundation of China (Grant No. 60971038)the Fundamental Research Funds for the Central Universities, China (Grant Nos. ZYGX2009Z003 and ZYGX2010J054)
文摘An open-styled dielectric-lined azimuthMly periodic circular waveguide （ODLAP-CW） for a millimeter-wave traveling-wave tube （TWT） is proposed, which is a modified form of a dielectric-lined azimuthally periodic circular waveguide （DLAP-CW）. The slow-wave characteristics of the open-styled DLAP-CW are studied by using the spatial harmonics method, which includes normalized phase velocity and interaction impedance. The complicated dispersion equations are numerically solved with MATLAB and the results are in good agreement with the simulation results obtained from HFSS. The influence of structural parameters on the RF properties is investigated based on our theory. The numerical results show that the optimal thickness of the metal rod can increase the interaction impedance, with the dielectric constant held fixed. Finally, the slow-wave characteristics and transmission properties of an open-styled structure are compared with those of the DLAP-CW. The results validate that the mode competition is eliminated in the improved structure with only a slight influence on the dispersion characteristics, which may significantly improve the stability of an open-styled DLAP-CW-based TWT, and the interaction efficiency is also improved.
文摘设计了一个基于交错双光栅的双路并联慢波结构,该结构采用两注电子及均匀恒磁场聚焦系统,具有平面二维结构。对该慢波结构的色散等冷测特性进行了详细研究,采用功分器和传输变换结构构成高频互作用电路,输出口为WR-2.8标准波导口,在305 GHz^335 GHz获得较好的传输特性,反射系数S11<-15 d B,传输系数S21>-4.4 d B。利用三维粒子模拟计算的方法,分析比较了单路及双路行波管放大特性。在电流密度53.57 A/cm2情况下增益达到14.586 d B,是一种极具发展潜力的太赫兹器件。
