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Decoupling technique of patch antenna arrays with shared substrate by suppressing near-field magnetic coupling using magnetic metamaterials 下载免费PDF全文
In this paper,we propose the decoupling technique of patch antenna array by suppressing near-field magnetic coupling(NFMC) using magnetic metamaterials.To this end,a highly-integrated magnetic metamaterials,the substrate-integrated split-ring resonator(SI-SRR),is firstly proposed to achieve negative permeability at the antenna operating frequency.By integrating SI-SRR in between two closely spaced antennas,magnetic fields are blocked in the shared substrate due to negative permeability of SI-SRR,reducing NFMC between the two antennas.To verify the technique,a prototype was fabricated and measured.The measured results demonstrated that the isolation can be enhanced by more than 17 dB even when the gap between the two patch antennas is only about 0.067 A.Due to high integration,this technique provides an effective alternative to high-isolation antenna array. 相似文献
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本文提出了一种基于人工表面等离激元的频率选择结构的设计方法:将设计的频率选择表面和金属鱼骨结构阵列相结合得到一种新的频率选择结构.文中采用这种方法设计了一种具有陡截止和高透、高抑制性能的双通带频率选择结构.该结构由金属鱼骨结构阵列和上下两层相同的频率选择表面复合而成.通过仿真可得,该结构的两个通带频率范围分别是3.0–4.1和10.5–10.9 GHz,透射率均在-0.5 dB以上.透射率低于-10 dB的频率范围是4.7–9.2和12.1–18 GHz.在12.4–15.5 GHz频率范围内,该结构的透射率甚至低于-20 dB.在通带内,电磁波可以高效地透过该结构;在阻带内,该结构对电磁波的透射具有较好的抑制作用.测试结果表明用这种方法设计出的频率选择结构的实际性能和仿真基本一致.在金属鱼骨结构空隙中填入轻质泡沫后该结构具有一定的力学承载性能,可以实现结构功能一体化的设计. 相似文献
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This paper reports that a general method of designing
invisible cloaks is using variant constitutive material
parameters to realize the space transformation. A hollow region can
be hidden after this transformation. It was recently shown (Ma H, Qu
S B, Xu Z and Wang J F 2009 \wx{Appl. Phys. Lett.}{94} 103501) that
when the original point moves to the boundary of a cloak, the cloak
can be designed to be open. Based on this theory, we propose
multi-window invisible cloaks which can conceal a group of objects.
Full wave simulations for invisible cloaks with regular and
irregular shapes verified this method. 相似文献
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提出了基于金属结构单元间耦合进行左手材料设计的思想,并建立了理论分析模型.通过合理选择结构单元的结构参数并通过单元之间的耦合,使电谐振等效电路的谐振频率与磁谐振等效电路的谐振频率相等,从而最大限度地实现宽左手频带.加工、制作并测试了基于金属结构单元间耦合的左手材料.实验结果表明,测试样品具有相等的电谐振频率和磁谐振频率,其左手频带的带宽为24 GHz.实验结果与理论分析一致,验证了基于金属结构单元间耦合的左手材料设计思想.
关键词:
左手材料
单元间耦合
等谐振频率
宽频带 相似文献
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By making a comparison between the acoustic equations and the
2-dimensional (2D) Maxwell equations, we obtain the material
parameter equations (MPE) for acoustic elliptical cylindrical
cloaks. Both the theoretical results and the numerical results
indicate that an elliptical cylindrical cloak can realize perfect
acoustic invisibility when the spatial distributions of mass density
and bulk modulus are exactly configured according to the proposed
equations. The present work is the meaningful exploration of
designing acoustic cloaks that are neither sphere nor circular
cylinder in shape, and opens up possibilities for making complex and
multiplex acoustic cloaks with simple models such as spheres,
circular or elliptic cylinders. 相似文献