一种超宽带平面天线的设计研究

设计一种小型超宽带平面天线,该天线为共面波导馈电的宽槽天线,其辐射贴片采用矩形与椭圆结构相结合的形式,并采用导带的圆形过度方法进行阻抗变换。在-10dB时的反射损耗带宽覆盖3.1～10.6GHz的频带范围,满足FCC所要求的超宽带无线通信带宽的要求,具有较好的应用前景。     

国外SAR天线的发展

本文简要介绍国外合成孔径雷达（ＳＡＲ）天线的发展，主要介绍国外空间大型可展开天线的定义，ＳＡＲ天线的特点，国外目前在微带平面阵天线结构设计上遵循的设计方法，以及大型微带平面阵ＳＡＲ天线在国外卫星上的应用。     

一种平面宽带单极天线的设计

设计一种新颖的平面宽带单极天线。该天线由矩形平板单极天线变形而来,通过U形槽、增加和折叠天线两臂,实现小型化、多模和低驻波比特性(在1.71～1.96GHz和2.38～6.37GHz频段内VSWR小于2)。通过CST软件进行仿真,分析各谐振的电流分布和谐振长度。该天线结构简单,尺寸较小(60mm×20mm),制作容易,可用于GSM/WLAN/WIMAX应用。通过加工测试,天线的仿真结果和实测结果非常吻合。     

共用天线电视系统的调试

共用天线电视系统的调试刘全巧（河南省工业设备安装工程公司洛阳４７１０００）１调试步骤（１）首先分析图纸，了解各接收频道空间场强，接收天线所处的位置，发射台的位置，发射台电波极化形式，语言台的频率，附近有无雷一达站及工业干扰。（２）检查天线馈线和匹配器...     

超低频拖曳磁场天线设计中的热噪声研究

通过对产生超低频拖曳磁场天线热噪声的原理以及各种天线构造参数对热噪声影响的研究，得出了在电缆浮力条件下保证最小热噪声ENF的最优化基本参数的表达式．结合对天线其它电参数的要求，探讨了利用最优化参数的可行性．分析结果表明，获得高可逆磁导率的磁芯是实现最优化参数的关键，并给出了解决这一问题的途径。     

基于导电银浆材料的RFID标签天线

为研究低成本的导电银浆天线性能,以超高频RFID标签天线为例,采用高效且环保的丝网印刷工艺制作了一款S形振子天线,并着重分析了其阻抗、回波损耗特性.通过软件仿真和实物测量结果对比发现,两者数据吻合良好,且性能符合标签天线的工程应用要求.这也表明,导电银浆可用于低成本的天线制造.     

十字型振子FSS在机（弹）载雷达天线隐身中的应用研究

在飞行器隐身技术的研究中发现，机（弹）载雷达天线将在飞行器鼻锥方向产生很强的RCS贡献，如何降低雷达天线的RCS而又保证自身雷达正常工作已成为目标隐身技术中的一个关键课题．文中介绍了由十字型振子单元构成的带阻式频率选择表面的选频特性，探讨了该表面在低RCS抛物面天线和低RCS卡塞格伦天线中的工程应用，分析了应用于主、副反射面天线的隐身性能，最后得出两点结论，指出在副反射面天线的工程应用中更容易实现。     

关于智能天线的分析

随着社会信息交流需求的急剧增加、个人移动通信的迅速普及，频谱已成为越来越宝贵的资源。智能天线采用空分复用（SDMA）．利用在信号传播方向上的差别，将同频率、同时隙的信号区分开来。本文介绍了智能天线的基本概念，并详细介绍了最小均方（LMS）算法和递归最小二乘（RLS）算法，给出了相关具体的运算。     

蝴蝶结形天线和天线阵列在纳米领域的应用

纳米天线具有广阔的前景,在介绍蝴蝶结形纳米天线和纳米天线阵列的基本构造和工作原理的基础上,综述其在多个科技前沿领域的应用。     

一种小型多频手机天线的设计

设计一个可以工作LTE700/GSM850/900和GSM1800/1900/UMTS/LTE2300/2500等多个频段的小型PCB手机天线。该天线直接印制在手机的系统电路板上,通过形变的F耦合进行馈电。利用Ansoft公司的HFSS三维仿真软件,对天线尺寸进行设计优化,结果表明,带内天线的回波损耗和天线增益均能满足多频手机的需要。     

Artificial Magnetic Conductor as Planar Antenna for 5G Evolution

A 5G wireless system requests a high-performance compact antenna device. This research work aims to report the characterization and verification of the artificial magnetic conductor (AMC) metamaterial for a high-gain planar antenna. The configuration is formed by a double-side structure on an intrinsic dielectric slab. The 2-D periodic pattern as an impedance surface is mounted on the top surface, whereas at the bottom surface the ground plane with an inductive narrow aperture source is embedded. The characteristic of the resonant transmission is illustrated based on the electromagnetic virtual object of the AMC resonant structure to reveal the unique property of a magnetic material response. The characteristics of the AMC metamaterial and the planar antenna synthesis are investigated and verified by experiment using a low-cost FR4 dielectric material. The directional antenna gain is obviously enhanced by guiding a primary field radiation. The loss effect in a dielectric slab is essentially studied having an influence on antenna radiation. The verification shows a peak of the antenna gain around 9.7 dB at broadside which is improved by 6.2 dB in comparison with the primary aperture antenna without the AMC structure. The thin antenna profile of λ/37.5 is achieved at 10 GHz for 5G evolution. The emission property in an AMC structure herein contributes to the development of a low-profile and high-gain planar antenna for a compact wireless component.     

星载抛物面天线反射器太阳辐射热流分析

太阳辐射是在轨抛物面天线反射器产生变形并导致其电性能下降的重要因素。针对天线轨道位置的时变性及抛物反射器的几何特点,讨论了太阳辐射光线与轨道面的夹角、进出地球阴影区的时刻等参数。根据抛物面方程以及太阳光辐射向量,运用几何方法分析抛物面天线的自遮挡作用,并给出了相应的判据,同时利用坐标变换实现天线反射面的对地指向不变。该方法实现对在轨抛物面天线反射器的太阳辐射热流的实时分析,为准确分析反射器的热变形或热颤提供条件。     

基于电子标签导电油墨厚度的研究

在电子标签的印制中,采用分层印刷电子标签天线的思路,提出了分层蝶形天线模型,并进行了仿真模拟,研究了墨层厚度对蝶形天线辐射效率的影响。由仿真结果分析可知:不同区域电流密度的高低影响分层天线的辐射效率,在天线上找到了分层最佳点,分层天线的辐射效率比单层天线高。解决了印刷天线墨层厚度与辐射效率矛盾的问题。     

导电油墨厚度对RFID标签天线辐射效率的影响

为提高RFID电子标签天线的辐射效率,从理论上分析了影响标签天线辐射效率的一系列因素,以偶极子和叠缝隙2种天线为研究对象,研究了导电油墨厚度对RFID标签天线的辐射效率的影响。结果表明:决定天线的辐射效率的是印刷标签天线所用的总油墨量,而不是整个天线结构中不同区域内油墨的分布情况。为实际RFID电子标签生产中导电油墨的控制和改进,提供一些指导。     

平面等角螺旋天线阵列/树脂复合材料的吸波性能研究

研究了含平面等角螺旋天线阵列复合材料的微波吸收特性,并对天线阵列的吸波机理进行了初步的探讨。结果表明:含平面等角螺旋天线阵列复合材料的吸波性能与天线的起始半径、外半径和两臂间电阻阻值密切相关,经合理设计,吸波材料的有效带宽达6.64GHz,最大吸收峰值-19dB。     

新型半模基片集成波导漏波天线

 为了设计一种结构简单、可靠性高的全向天线,提出了一种基于半模基片集成波导技术的漏波天线.这种天线是在半模基片集成波导结构的H壁增加4个对称振子形成的漏波辐射结构.使用电磁仿真软件对提出的天线结构进行了精确的建模,分析了介质厚度对天线带宽的影响,并对天线结构进行了优化,最后制作了天线测试样片进行实验验证.所设计的天线具有较宽的带宽和准全向辐射的特性,在7.3~9.7 GHz频段内具有良好的辐射性能,最大增益为5.8 dBi,测试结果验证了设计的有效性．     

Design and performance of cryogenic enclosures for long duration testing of large samples

We have designed a large helium dewar as part of an experiment to investigate gravitational radiation. Two such dewars have been constructed. Our use requires a nonmagnetic dewar to cool an aluminium antenna of approximately 5000 kg to below helium temperatures and to keep the antenna in a stable low temperature environment for extended time. This requires a low temperature volume of 1.5 m inner diameter and 3.1 m length and a cooling system capable of efficiently removing the room temperature enthalpy of 8.5 × 10⁸ J. Our solution to this problem is of wider application than simply gravity wave detection so we have discussed the design philosophy in some detail. As constructed, the apparatus uses less than 1 l of helium per hour when cold.     

Ultra-wideband antenna with improved gain characteristics

A ultra-wideband (UWB) antenna with improved gain characteristics is proposed. With the improvements, it is discussed in terms of the band notch and enhanced radiation patterns. Shaping the return loss as an approach in order to achieve these characteristics is introduced and a multi-resonant dipole structure is designed and experimented in frequency and time domains. The proposed UWB antenna provides the band notch with a sharp slope and improved gain deviation on azimuth plane for the UWB communication.     

CPW-fed ultra wideband slot antenna with arc-shaped stub

An ultra wideband coplanar waveguide (CPW) fed slot antenna is presented. A rectangular slot antenna is excited by a 50-CPW with an arc-shaped tuning stub. For the proposed antenna, the 210 dB return loss bandwidth could reach 15.6 GHz (3.7-19.3 GHz), which is about 135% with respect to the centre frequency of 11.5 GHz. Details of the antenna design, simulation and measured results on the return loss and the E-and H-plane radiation patterns of the proposed antenna are presented.     

Dual-polarisation and dual-pattern planar antenna for diversity in body-centric communications

A novel dual-polarisation/dual-pattern stripline-fed annular-ring slot antenna for body-centric communication systems working in the IEEE 802.11a frequency band at 5.725-5.825-GHz is presented. A stripline feeding technique has been implemented in order to reduce the back radiation level and make the antenna suitable for wearable communication systems. The planar antenna has been designed to provide capabilities for implementation of a polarisation/pattern diversity scheme in body-centric communications. Two prototypes have been fabricated and characterised. The design criteria are described and measurements of return loss, isolation between ports, principal plane radiation patterns and radiation efficiency are shown. A measurement campaign has also been carried out to evaluate the diversity scheme performance.