一种星载SAR的新型双极化微带贴片天线

提出了一种适用于星载SAR的新型双极化微带贴片天线。在孔径耦合馈电基础上,采用同轴线到微带线垂直过渡的方式,设计了一种新型双极化天线单元,在保持孔径耦合贴片天线固有优点的同时,使得交叉极化、隔离度得到很好改善,同时节约了阵中空间。该天线适合作为星载SAR阵列天线单元。     

Ku 波段全口径高隔离度双极化阵列天线的研究

本文提出并设计制作了一种新型的全口径高隔离度双极化单脉冲阵列天线。该阵列天线单元采用微带贴片与喇叭复合的形式,将微带贴片作为喇叭的二次激励源,以获得更高的单元增益。其中的微带贴片采用一对相互垂直的带状线通过两个呈“T”型分布的“H”形缝隙耦合馈电,以获得较高的极化隔离度（在工作频带内小于-35dB）。在阵列馈电设计中采用二次错位倒相技术,进一步改善了极化隔离度和交叉极化。仿真和实测结果表明,在f0±200MHz 内,驻波比小于2,垂直极化增益大于27dB,水平极化增益大于27.5dB,端口极化隔离度小于-40dB,和差端口隔离度小于-28dB。     

一种宽带高隔离度双极化微带天线的设计

设计了一种宽带高隔离度的双极化微带天线,天线的两个馈电端口分别采用了H型口径耦合和容性加载H型口径耦合,在展宽带宽的同时提高了双端口隔离度,同时利用反射板使天线获得较高增益。HFSS仿真和实测结果表明天线双极化端口的阻抗带宽（VSWR〈2）达40%,增益达到8 dB以上,端口隔离度大于33 dB,该天线可被广泛应用于双极化天线阵系统中。     

一种可用于5G点对点通信的宽频双极化阵列天线

本文设计了一款高增益宽频双极化天线。该天线采用多层辐射贴片的结构，拓展天线的带宽，并用一对正交分布的微带线直接馈电在辐射贴片上，增强天线极化隔离度，形成双极化特性。通过设计馈电网络，组成阵列后实现良好的带宽与定向辐射特性，并且具有良好的端口隔离度和辐射极化纯度。实测结果表明，小于-10dB的阻抗带宽为18.18%(5.0～6.0GHz),带内平均增益为15.5dBi,全频段端口隔离度小于-30dB,主瓣方向上的主极化电平与交叉极化电平相差40dB,带内增益波动小于3dB,具有良好的增益平坦度。该天线适合作为5G通信系统中的天线单元，具有实用价值。     

L 型探针馈电在WLAN 天线设计中的应用

介绍了一种L形探针耦合馈电的天线形式。天线为正交双极化贴片天线,每一个极化由双端口反相合成馈电,具 有隔离度高,工作频带宽,剖面低等特点。阻抗带宽可达25%,隔离度大于30dB,天线的最大高度小于23mm。该天线形 式在实际产品中得到了应用。     

C波段宽带双极化微带贴片天线设计

针对宽带双极化天线高隔离度难以实现的问题,设计了一种C波段宽带双极化微带贴片天线,天线单元采用口径耦合馈电的双层微带贴片形式来拓展带宽。为了提高2种极化端口的隔离,在地板上开一对相互垂直的H型缝隙,馈电微带线匹配枝节采用T字型结构。仿真结果表明,该天线在C波段相对阻抗带宽达21%(驻波小于2),具有良好的端口隔离度和高交叉极化抑制度。     

一种新型宽带双极化微带贴片天线的设计

摘要：运用口径耦合理论、腔模理论、反相馈电技术和多层贴片结构设计出一种新型的P波段（中心频率为0．75GHz）宽带双极化微带贴片天线。天线的两个极化端口采用共面馈电;馈电网络设计中采用短路耦合线实现反相馈电。仿真结果表明该天线两个极化端口实际增益均达到8．5dB,水平极化端口在0．64-0．85GHz频率范围内驻波比小于2,相对带宽为28％;垂直极化端口在0．68-0．85GHz频率范围内驻波比小于2,相对带宽为22．6％,两端口隔离度高于53dB。     

双频段双极化微带天线阵列设计*

设计了一种双频段双极化的阵列天线。该阵列天线采用多层微带天线形式,七层结构,通过口径耦 合和微带线边馈两种馈电方式实现双线极化,在辐射贴片上方增加寄生贴片以扩展带宽,实现双频段。天线工作在 12.25 ~12.75GHz 及14 ~ 14.5GHz,实测增益18dB 左右,隔离度大于40dB。该天线剖面低,重量轻,可作为子阵组 成更大规模的双频段双极化阵列。     

一种十字形缝隙耦合的Ku波段宽频带双极化微带天线

采用十字缝隙耦合,层叠贴片和微带线馈电的结构形式,设计了一种适用于Ku波段的宽频带双极化微带天线。利用电磁仿真软件CST 5.0微波工作室对天线的电特性进行仿真优化,并制作了实物模型,实测结果和仿真结果吻合良好。两馈电端口回波损耗小于-10 dB的阻抗带宽分别达到34.2%和28.7%,端口隔离度高于21.4 dB。     

一种双极化宽带相控阵贴片天线的设计

相控阵天线是由相位来控制波束指向的阵列天线,大带宽、双极化等特性是相控阵天线的特点.L型馈电和孔径耦合贴片天线带宽可达20％,但是一致性差,并且隔离度不高.针对上述问题,文章分析、改进了一种H缝隙的贴片天线并将之应用于相控阵领域,计算和测试结果表明:该种形式的双极化贴片天线完全可以应用于低剖面且具有较大带宽的相控阵天线,具有较大的实际应用价值.     

一种槽耦合的双频双极化微带天线

设计了一种适用于基站天线的双频双极化微带天线单元,该天线单元采用槽耦合、多层贴片和对称馈电的结构形式。用商业软件Ansoft对天线的电特性进行仿真计算,制作了实验模型,测试结果优于仿真结果。天线在880-960MHz的GSM（全球移动通信系统）频段和1710～1880MHz的DCS（数字蜂窝系统）频段上的反射损耗均大于10dB,在两个频段上极化互相垂直的两个端口的隔离度均大于24dB。     

一种新颖的宽频带双极化基站单元天线研究

提出了一种新颖的宽频带双极化方形偶极子基站天线单元,该天线单元由圆柱形支撑座、方形偶极子单元、改进的双倒L型馈电线以及反射板组成。仿真和测试结果显示,在1.69 GHz~3.16 GHz 频段内,两个端口处的电压驻波比(VSWR)均小于1.5,其中,在所需要的工作频段1.71 GHz~2.69 GHz 内,两端口的VSWR均小于1.4,隔离度小于-30 dB,交叉极化比均小于-29 dB,最大增益为10.6 dB,在整个宽频带内具有较为稳定的方向图和增益。同时,该天线经过改进后重量轻,馈线可调性好,安装简单易实现。     

并行角馈双极化微带天线阵的分析与设计

本文提出利用双端口的并行角馈实现双极化天线,并设计了一种新的双极化馈线网络。综合运用了多端口网络模型、腔模理论、分片法和补片法,给出了各天线单元和双极化馈线网络的理论分析方法。实际设计了一副6GHz频段的单层共面的四元天线阵,实测的双端口隔离度达-50dB,其性能明显优越于通常的单层双极化微带天线阵列。     

Dual-polarized slot-coupled planar antenna with wide bandwidth

A new dual-polarized slot-coupled microstrip patch antenna is presented, which can achieve high-isolation, low cross-polarization levels, a wide bandwidth, and low backward radiation levels. The coupling slot is an H-shaped slot. For wide bandwidth and easy integration with active circuits, it uses slot-coupled stacked microstrip patches. The theoretical analysis is based on the finite-difference time-domain (FDTD) method. First, a parametric study on the input impedance of the antenna with a single input port is presented. Based on the results, a dual-polarized microstrip antenna is designed, fabricated, and then measured. The measured return loss exhibits an impedance bandwidth of over 20.9% and the isolation between two polarization ports is better than 36 dB over the bandwidth. The cross-polarization levels in both E and H planes are better than 22 dB. The front-to-back ratio of the antenna radiation pattern is better than 21 dB. Both theoretical and experimental results of return loss, isolation, and radiation patterns are presented and discussed.     

Design of dual-polarized L-probe patch antenna arrays with high isolation

An experimental study of a dual-polarized L-probe patch antenna is presented. The antenna is designed to operate at around 1.8 GHz. A "dual-feed" technique is introduced to achieve high isolation between two input ports. The proposed antenna has an impedance bandwidth of 23.8% (SWR/spl les/2), 15% (SWR/spl les/1.5) and an isolation over 30 dB. In array designs, techniques for improving the isolation between two adjacent elements of an antenna array are also investigated. A two-element array with more than 30 dB isolation is designed and tested.     

Design of wideband dual-band dual-polarized dipole for base station antenna

This article put forward a novel dual-band dual-polarized magneto-electric dipole antenna excited by F-shaped strips. The proposed antenna achieved a common impedance bandwidth of 25.5% and 39.5% in the lower and the upper bands at both input ports, ranged from 0.75 GHz to 0.97 GHz and from 1.73 GHz to 2.59 GHz respectively. The antenna has good performance in isolation, which is more than ?32 dB between the two input ports, and the gain of the antenna is average 4.3 dB and 7.8 dB in the lower and upper bands. The antenna has a stable broadside radiation pattern with low cross polarization and low back lobe radiation over the operating band. Metallic side walls on the ground are added for better performance in gain and radiation pattern.     

Research on dual-polarized circular waveguide antenna fed by L-shaped probes

This paper researched a kind of dual-polarized and cylindrical waveguide antenna fed by two L-shaped probes at the antenna bottom. The designed antenna was composed of two orthogonal L-shaped coaxial probes and a cylindrical waveguide cavity. The two orthogonal field structures were excited and the dual-polarized radiation mode was formed. The feeding cables of two polarization ports went through the bottom of the cylindrical cavity and were connected with the microwave adaptors. The bottom feeding structure was suitable to constitute a planar antenna array. The electromagnetic simulation and optimization design of the proposed antenna were carried out by using the full wave electromagnetic simulation technique, and the simulation results showed that the isolation between two polarization ports were more than 20 dB within the frequency range of 4.8–5.4 GHz. At the center frequency, the cross-polarization levels of radiation pattern were lower than −21 dB at the boresights and the beam width of radiation patterns at E-plane and H-plane were more than 70° for two polarization ports. The designed antenna in this paper was fabricated and measured. The measurement results indicated that the designed antenna achieved anticipated radiation performances and design effectiveness of the dual-polarized antenna in this paper was proved. The dual-polarized and cylindrical waveguide antenna is suitable for some application fields such as dual-polarized array radar. The research results in this paper can provide a technical basis for the practical engineering application.