提出了一种张量人工阻抗单元的表面阻抗分析计算方法,主要对矩形形状单元的表面阻抗开展了研究。通过仿真软件Ansys-HFSS提取了人工阻抗单元表面的入射散射场,再利用等效传输线技术计算出表面的张量阻抗。利用张量阻抗与表面场的关系,...提出了一种张量人工阻抗单元的表面阻抗分析计算方法,主要对矩形形状单元的表面阻抗开展了研究。通过仿真软件Ansys-HFSS提取了人工阻抗单元表面的入射散射场,再利用等效传输线技术计算出表面的张量阻抗。利用张量阻抗与表面场的关系,给出了人工阻抗单元的标量阻抗与传播方向的关系,验证了计算的准确性。最后作为实例,设计了一种基于张量阻抗单元的圆极化全息天线,天线具有较好的圆极化特性,增益大于21 d B。展开更多
For conveniently calculating the radiated electric field of transverse electromagnetic(TEM) horn antenna,an approximate simplified analytical calculation method is suggested.This method divides the horn to a system of...For conveniently calculating the radiated electric field of transverse electromagnetic(TEM) horn antenna,an approximate simplified analytical calculation method is suggested.This method divides the horn to a system of V-antennas and superimposes the fields of all V-antennas to obtain the field of the TEM horn.The method is compared with the traditional analytical method and numerical method.The obtained results suggest that the proposed method is valid,simple and that it can fastly calculate the radiated electric field of the TEM horn antenna in an arbitrary space with an arbitrary excitation voltage.Based on this method,radiation of the TEM horn antenna of a high-altitude electromagnetic pulse(HEMP) simulator is simulated.Rise time,pulse width,peak value of electric field,and field distribution are analyzed.Results show that the TEM horn antenna can be used in HEMP simulators: the near field waveform is closer to the standard waveform than to the far field waveform; the standards for the rise time and the peak value of electric field are easily satisfied; the pulse width of the radiated field can be increased by broadening the pulse width of an excitation source and by making the antenna of a proper展开更多
A new structure of dielectric waveguide for millimeter waveband namedgroove nonradiative dielectric(GNRD)waveguide and a leakywave antenna based on thisstructure are developed in this paper.The GNRD structure overcome...A new structure of dielectric waveguide for millimeter waveband namedgroove nonradiative dielectric(GNRD)waveguide and a leakywave antenna based on thisstructure are developed in this paper.The GNRD structure overcomes the difficulty of as-sembling precisely the dielectric strip in the nonradiative dielectric(NRD)structure.Thedispersion characteristics of the GNRD waveguide,and the propagation and radiationcharacteristics of the GNRD leakywave antcnna have been analysed by the use of thetransverse rcsonance mcthod.The theoretical results are in good agreement with the exper-imental data.展开更多
The formula of input impedance of dipole antenna in Gigahertz Transverse ElectroM agnetic(GTEM) cell based on the dyadic Green's function is first obtained in this paper. The validation of the formula is verified ...The formula of input impedance of dipole antenna in Gigahertz Transverse ElectroM agnetic(GTEM) cell based on the dyadic Green's function is first obtained in this paper. The validation of the formula is verified by the results of theoretical derivation and simulation with well agreements. In comparison with the formula of input impedance in free space, the relationship between the change of input impedance with the length of antenna and the position of antenna in GTEM cell is obtained. In addition, some meaningful conclusions are presented, which not only can be referred by the further research of ElectroM agnetic Interference(EMI) measurements in GTEM cell, but also provide the theoretical basis for testing compensation and error analysis.展开更多
文摘提出了一种张量人工阻抗单元的表面阻抗分析计算方法,主要对矩形形状单元的表面阻抗开展了研究。通过仿真软件Ansys-HFSS提取了人工阻抗单元表面的入射散射场,再利用等效传输线技术计算出表面的张量阻抗。利用张量阻抗与表面场的关系,给出了人工阻抗单元的标量阻抗与传播方向的关系,验证了计算的准确性。最后作为实例,设计了一种基于张量阻抗单元的圆极化全息天线,天线具有较好的圆极化特性,增益大于21 d B。
基金Project supported by National Natural Science Foundation of China(51177174).
文摘For conveniently calculating the radiated electric field of transverse electromagnetic(TEM) horn antenna,an approximate simplified analytical calculation method is suggested.This method divides the horn to a system of V-antennas and superimposes the fields of all V-antennas to obtain the field of the TEM horn.The method is compared with the traditional analytical method and numerical method.The obtained results suggest that the proposed method is valid,simple and that it can fastly calculate the radiated electric field of the TEM horn antenna in an arbitrary space with an arbitrary excitation voltage.Based on this method,radiation of the TEM horn antenna of a high-altitude electromagnetic pulse(HEMP) simulator is simulated.Rise time,pulse width,peak value of electric field,and field distribution are analyzed.Results show that the TEM horn antenna can be used in HEMP simulators: the near field waveform is closer to the standard waveform than to the far field waveform; the standards for the rise time and the peak value of electric field are easily satisfied; the pulse width of the radiated field can be increased by broadening the pulse width of an excitation source and by making the antenna of a proper
文摘A new structure of dielectric waveguide for millimeter waveband namedgroove nonradiative dielectric(GNRD)waveguide and a leakywave antenna based on thisstructure are developed in this paper.The GNRD structure overcomes the difficulty of as-sembling precisely the dielectric strip in the nonradiative dielectric(NRD)structure.Thedispersion characteristics of the GNRD waveguide,and the propagation and radiationcharacteristics of the GNRD leakywave antcnna have been analysed by the use of thetransverse rcsonance mcthod.The theoretical results are in good agreement with the exper-imental data.
基金Supported by Chinese Academy of Sciences(No.Y140110213)
文摘The formula of input impedance of dipole antenna in Gigahertz Transverse ElectroM agnetic(GTEM) cell based on the dyadic Green's function is first obtained in this paper. The validation of the formula is verified by the results of theoretical derivation and simulation with well agreements. In comparison with the formula of input impedance in free space, the relationship between the change of input impedance with the length of antenna and the position of antenna in GTEM cell is obtained. In addition, some meaningful conclusions are presented, which not only can be referred by the further research of ElectroM agnetic Interference(EMI) measurements in GTEM cell, but also provide the theoretical basis for testing compensation and error analysis.