Two kinds of compact electromagnetic band gap (EBG) structures are designed. A two layer compact EBG structure configured with cross spiral shape line inductors and interdigital capacitors is first presented. Becaus...Two kinds of compact electromagnetic band gap (EBG) structures are designed. A two layer compact EBG structure configured with cross spiral shape line inductors and interdigital capacitors is first presented. Because of its significantly enlarged equivalent inductor and capacitance, the period of the lattice is approximately 4.5% of the free space wavelength. By insetting several narrow slits in the ground plane, the bandwidth of the main bandgap is enhanced by nearly 19%. Further effort has been made for designing a three layer compact EBG structure. Simulation results show that its period is reduced by about 26% compared to that of proposed two layer EBG structure, and the bandwidth of the main bandgap is about 3 times as that of the proposed two layer EBG structure. The detailed designs including a two layer compact 3×7 EBG array with and without defect ground plane and the three layer EBG array are given and simulation results are presented.展开更多
An Electromagnetic Band Gap (EBG) loaded square waveguide Band-Pass Filter (BPF) is proposed in this paper. It’s simply composed by symmetrically loading periodical metal diaphragms on each wall of a square waveguide...An Electromagnetic Band Gap (EBG) loaded square waveguide Band-Pass Filter (BPF) is proposed in this paper. It’s simply composed by symmetrically loading periodical metal diaphragms on each wall of a square waveguide. The influences of insert sizes and loading periods on the overall BPF performances are analyzed. Experimental results agree well with those predicted. 6 GHz pass-band with insert loss less than 1 dB, 2.5 GHz stop-band and larger than 25 dB polarization isolation can be obtained. The BPF can be applied in dual-polarized waveguide-based antenna-feed systems.展开更多
A rectangular waveguide band-stop filter using electromagnetic crystals (EMXT) surface as the top and bottom walls is presented in this letter. The EMXT surface has a band gap that can prevent electromagnetic wave fro...A rectangular waveguide band-stop filter using electromagnetic crystals (EMXT) surface as the top and bottom walls is presented in this letter. The EMXT surface has a band gap that can prevent electromagnetic wave from propagating along the waveguide. Dispersion properties of the waveguide filter are analyzed using an approximated lumped-element circuit model. A W-band prototype based on the proposed waveguide filter is designed and characterized. The experimental results show a rejection band centered at 97 GHz and a rejection level of 16 dB.展开更多
提出了一种分析多层印刷电路板电源分配网络(power distribution network,PDN)中一维(1D)介质型电磁带隙(electromagnetic band-gap,EBG)结构噪声隔离性能的1D有限元数值计算方法.将1D介质型EBG的3D结构简化为1D有限元模型,通过直接求...提出了一种分析多层印刷电路板电源分配网络(power distribution network,PDN)中一维(1D)介质型电磁带隙(electromagnetic band-gap,EBG)结构噪声隔离性能的1D有限元数值计算方法.将1D介质型EBG的3D结构简化为1D有限元模型,通过直接求解波动方程获得传输系数T、反射系数R以及散射参数S.利用R-T曲线可直观地判定频率禁带,而采用分贝表示的S21参数则更方便评价噪声隔离度.根据介质型EBG的周期数、介电常数和周期长度等参数对噪声隔离性能影响的仿真结果,针对少周期、不完全禁带EBG结构提出了先采用多周期EBG结构预测禁带,再通过调整介电常数和周期长度扩展禁带和增强噪声隔离度的两阶段设计方法.采用3D全波电磁仿真验证了1D有限元算法的合理性.展开更多
Six circularly polarized patch antennas with electromagnetic band gap(EBG)arranged at different locations were studied.These EBG antennas were compared in terms of impedance bandwidth,axial ratio(AR)bandwidth and ...Six circularly polarized patch antennas with electromagnetic band gap(EBG)arranged at different locations were studied.These EBG antennas were compared in terms of impedance bandwidth,axial ratio(AR)bandwidth and radiation patterns.When the EBG cells were placed closer to the edge of the substrate,the EBG antenna had a larger front radiation and a narrower bandwidth.Integrating the EBG cells closer to the center of the patch resulted in a wider impedance bandwidth,a wider axial ratio bandwidth and a decreased front gain.展开更多
将Mushroom电磁带隙结构(Electromagnetic Band Gap,EBG)的表面波带隙和同相反射特性同时用于波导缝隙阵列天线的设计,利用EBG的带隙特性抑制天线阵中的表面波,以改善天线的辐射性能;利用EBG的同相反射特性实现天线雷达散射截面(Radar C...将Mushroom电磁带隙结构(Electromagnetic Band Gap,EBG)的表面波带隙和同相反射特性同时用于波导缝隙阵列天线的设计,利用EBG的带隙特性抑制天线阵中的表面波,以改善天线的辐射性能;利用EBG的同相反射特性实现天线雷达散射截面(Radar Cross Section,RCS)的减缩,天线综合性能得到较大提升。制作了EBG波导缝隙天线阵样品,并对天线阵的阵元互耦、辐射方向图及天线阵RCS等指标进行了测试,结果与理论预期相吻合,有效地降低了阵元间互耦及天线阵RCS。展开更多
基金supported by the National Natural Science Foundation of China under Grant No. 60588502
文摘Two kinds of compact electromagnetic band gap (EBG) structures are designed. A two layer compact EBG structure configured with cross spiral shape line inductors and interdigital capacitors is first presented. Because of its significantly enlarged equivalent inductor and capacitance, the period of the lattice is approximately 4.5% of the free space wavelength. By insetting several narrow slits in the ground plane, the bandwidth of the main bandgap is enhanced by nearly 19%. Further effort has been made for designing a three layer compact EBG structure. Simulation results show that its period is reduced by about 26% compared to that of proposed two layer EBG structure, and the bandwidth of the main bandgap is about 3 times as that of the proposed two layer EBG structure. The detailed designs including a two layer compact 3×7 EBG array with and without defect ground plane and the three layer EBG array are given and simulation results are presented.
文摘An Electromagnetic Band Gap (EBG) loaded square waveguide Band-Pass Filter (BPF) is proposed in this paper. It’s simply composed by symmetrically loading periodical metal diaphragms on each wall of a square waveguide. The influences of insert sizes and loading periods on the overall BPF performances are analyzed. Experimental results agree well with those predicted. 6 GHz pass-band with insert loss less than 1 dB, 2.5 GHz stop-band and larger than 25 dB polarization isolation can be obtained. The BPF can be applied in dual-polarized waveguide-based antenna-feed systems.
文摘A rectangular waveguide band-stop filter using electromagnetic crystals (EMXT) surface as the top and bottom walls is presented in this letter. The EMXT surface has a band gap that can prevent electromagnetic wave from propagating along the waveguide. Dispersion properties of the waveguide filter are analyzed using an approximated lumped-element circuit model. A W-band prototype based on the proposed waveguide filter is designed and characterized. The experimental results show a rejection band centered at 97 GHz and a rejection level of 16 dB.
文摘提出了一种分析多层印刷电路板电源分配网络(power distribution network,PDN)中一维(1D)介质型电磁带隙(electromagnetic band-gap,EBG)结构噪声隔离性能的1D有限元数值计算方法.将1D介质型EBG的3D结构简化为1D有限元模型,通过直接求解波动方程获得传输系数T、反射系数R以及散射参数S.利用R-T曲线可直观地判定频率禁带,而采用分贝表示的S21参数则更方便评价噪声隔离度.根据介质型EBG的周期数、介电常数和周期长度等参数对噪声隔离性能影响的仿真结果,针对少周期、不完全禁带EBG结构提出了先采用多周期EBG结构预测禁带,再通过调整介电常数和周期长度扩展禁带和增强噪声隔离度的两阶段设计方法.采用3D全波电磁仿真验证了1D有限元算法的合理性.
基金Supported by the National Natural Science Foundation of China(61102022)the Fundamental Research Foundation of Beijing Institute of Technology of China(20120542014)
文摘Six circularly polarized patch antennas with electromagnetic band gap(EBG)arranged at different locations were studied.These EBG antennas were compared in terms of impedance bandwidth,axial ratio(AR)bandwidth and radiation patterns.When the EBG cells were placed closer to the edge of the substrate,the EBG antenna had a larger front radiation and a narrower bandwidth.Integrating the EBG cells closer to the center of the patch resulted in a wider impedance bandwidth,a wider axial ratio bandwidth and a decreased front gain.
文摘将Mushroom电磁带隙结构(Electromagnetic Band Gap,EBG)的表面波带隙和同相反射特性同时用于波导缝隙阵列天线的设计,利用EBG的带隙特性抑制天线阵中的表面波,以改善天线的辐射性能;利用EBG的同相反射特性实现天线雷达散射截面(Radar Cross Section,RCS)的减缩,天线综合性能得到较大提升。制作了EBG波导缝隙天线阵样品,并对天线阵的阵元互耦、辐射方向图及天线阵RCS等指标进行了测试,结果与理论预期相吻合,有效地降低了阵元间互耦及天线阵RCS。