Ku波段宽角扫描圆极化微带阵列天线设计

提出了一种三馈电圆极化微带天线。天线馈电网络采用一分三功分馈电,实现微带贴片天线的圆极化辐射,增加方向图的旋转对称性。用该天线作为阵列单元,采用顺序旋转布阵技术组成一个3×4阵列,有效地改善了阵列天线的增益扫描特性。研究了该阵列天线波束扫描时的辐射特性和极化特性。仿真结果表明:阵列天线在中心工作频率处能实现俯仰60°的扫描,在扫描范围内增益大于11.9 d Bi,轴比小于2 d B。     

宽带圆极化锥形辐射单元阵列天线的设计

基于L型探针馈电提出了一种宽带圆极化锥形辐射单元天线的设计方法.为了提高轴比带宽,馈电网络应用带L型馈电探针的宽带90°电桥,锥台单元取代普通平面贴片作为辐射单元.4个单元组阵后可得到的峰值增益为12.7 dB.馈电网络在介质基板的底面以此来减小天线总体尺寸.测量结果与仿真结果吻合良好,天线可实现40.1%(VSWR<...     

一种方向图可重构圆极化阵列天线的设计北大核心CSCD

为了实现天线波束的灵活重构和调控,提出了一种方向图可重构圆极化阵列天线。阵列天线选用L型探针耦合馈电以拓宽阻抗带宽和圆极化轴比带宽,并基于提出的相位变换器设计输出端口间相位差可调的馈电网络。通过控制馈电网络中相位变换器上各PIN二极管工作状态,实现了天线的主辐射波束指向在+40°,+15°,-15°和-40°角度间切换。实测结果表明,该阵列天线在四种工作状态下的重叠阻抗带宽约为22%(2.2~2.74 GHz),重叠轴比带宽约为12.2%(2.33~2.62 GHz),且圆极化峰值增益为6.48 dBi。     

L波段极化可重构的圆极化滤波天线设计

本文提出了一种工作于L波段的极化可重构圆极化滤波天线,该天线由方形贴片辐射单元、滤波馈电网络和开关电路三个部分组成.其中,滤波馈电网络由一个3dB微带电桥和多个微带半波长开环谐振器构成,可以产生两路相位差90°/-90°的信号,并通过探针激励方形贴片以产生圆极化波.通过开关电路切换,可以控制滤波馈点网络的两路输出相位差...     

馈电相位可调极化可重构微带贴片天线

设计了一种相位可调的极化可重构微带贴片天线.该天线采用双馈电方式工作,通过改变馈电网络中4个单刀双掷开关的导通状态在两个馈电点形成不同的相位差,从而实现左旋圆极化、右旋圆极化以及线极化之间的切换.实验结果与理论分析和仿真结果相吻合,天线实现了良好的极化重构能力.特别是不同极化状态下,天线工作频率具有良好的一致性.     

用于移动卫星系统的宽波束双频微带天线

设计了一种新型的宽波束双频双圆极化层叠结构微带介质天线,该天线可发射L波段的左旋圆极化信号,接收S波段的右旋圆极化信号。天线通过展宽上下2层微带贴片的介质衬底,从而增大天线的波束宽度,3 dB波束宽度可达到160°以上。同时采用4馈点馈电的层叠结构,使用2个3 dB宽带电桥分别对上下2层贴片进行馈电,实现圆极化的同时也大大提高了效率,而且通过调节馈电的位置可以很容易的实现匹配,实验结果表明,该天线具有较好的收发隔离度,非常宽的3 dB波束宽度,而且在波束范围内都有很好的圆极化特性。     

采用新型馈电结构的双频宽带导航天线设计

基于新馈电结构,设计了一款覆盖全球四大卫星导航系统的双频宽带贴片天线。采用了一种四分八馈电线路,以8个同轴馈电探针两两相连的方式将两路天线馈电信号合为一路,有效简化了馈电网络的复杂性,同时保证了天线辐射的增益、带宽和轴比性能。该双频辐射贴片单元采用正八边形层叠式结构设计,并在每个天线单元边缘对称添加两组矩形调谐单元,有效增加了天线辐射的波束带宽。该双频天线单元在高频1.482~1.617 GHz（波束带宽155 MHz）和低频1.191~1.252 GHz(波束带宽61 MHz）频段范围内,都能保证良好的辐射增益;高低频的3 dB轴比带宽为-130°~130°,具备良好的圆极化性能。经实物样机对比测试分析,实测结果与仿真结果基本吻合。     

Ku波段宽带高增益基片集成腔圆极化阵列天线北大核心CSCD

提出了一款应用于Ku波段的宽带高增益基片集成腔(Substrate Integrated Cavity,SIC)圆极化阵列天线。通过引入沿SIC口径面对角线放置的一对半月形寄生贴片和SIC底部馈电纵缝,使SIC中的TM_(211)和TM_(121)谐振模式幅值相等、相位相差90°,产生高增益圆极化辐射。同时,双寄生贴片还引入了一种背腔缝隙耦合振子圆极化辐射模式,扩宽了天线高增益圆极化辐射带宽。在此基础上,设计了一款2×2单元顺序旋转馈电的SIC圆极化阵列天线。阵列天线采用双层基片集成波导顺序相移馈电网络进行馈电,进一步增大了天线的圆极化带宽。综合考虑天线的-10 dB反射系数带宽、3 dB轴比带宽和3 dB增益带宽,测试结果表明,圆极化阵列天线的有效带宽为10.74-13.30 GHz(21.3%),在通带范围内最大增益为14.50 dBi。     

一种带滤波功能的圆极化可控阵列天线

提出了一种带滤波功能的2′2圆极化可控阵列天线,采用探针对每个辐射贴片进行馈电,通过控制辐射贴片的激励相位和极化,实现整个阵列天线的圆极化特性。嵌入在阵列天线馈电网络中的耦合谐振器对保证了馈电网络在幅度响应上呈现滤波特性的同时,在相位上控制每个辐射贴片激励端口处的信号相位在-90°和90°之间变化,同时结合90°移相网络,可实现对整个阵列天线左旋圆极化(LHCP)和右旋圆极化(RHCP)的控制。实测结果表明:该阵列天线能控制辐射的圆极化特性,并获得优异的LHCP和RHCP特性;在两种极化状态下,阵列天线工作频带内均具有较为平坦的增益特性,平均增益为10.4 dBic,带外增益特性呈现较好的滤波特性,在远离通带上、下边带100 MHz 处增益抑制均达到8.6 dB以上。     

3种不同馈电方式的半球面螺旋天线分析

基于曲线基函数的矩量法分析了中心馈电、侧边馈电和顶端馈电的半球面螺旋天线的辐射特性。结果表明,半球面螺旋天线具有较好的阻抗特性和方向图特性,具有较宽的圆极化带宽。顶端馈电的半球面螺旋天线具有较宽的增益带宽,其辐射波束的角度比较宽。半球面螺旋天线具有更低的剖面,可以稳定地固定于反射板上,稳定性强,更加具有实际应用价值,在卫星通信领域有着巨大的应用前景。     

Implementation of Vertex-Fed Multiband Antenna for Wireless Applications with Frequency Band Reconfigurability Characteristics

In this paper authors present the design and analysis of split ring resonator based multiband antenna for wireless applications with frequency-band reconfigurable features. The proposed design has octagonal shape SRR structure fed at vertex as radiating section and rectangular shape switchable slotted ground part. The antenna has dimensions of 44?×?39?×?1.6 mm³ and fabricated on FR4 substrate. The proposed structure exhibit hexa operating resonance characteristics at 3.3, 5.0, 5.8, 6.6, 9.9 and 15.9 GHz to cover the wireless standards at lower WiMAX, upper WLAN, super extended C-band, middle X band and lower K_U band respectively. Antenna achieve the frequency band reconfigurability characteristics by inserting PIN diode in slotted ground (reclined L-shaped) as triple/hexa resonant bands during OFF/ON switching state of PIN diode. An acceptable gain, stable and consistent radiation patterns with low cross polarization and good impedance matching are obtained at targeted frequency bands of proposed design.

     

Researches on Reconfigurable Antenna in CEMLAB at UESTC

This paper summarizes the achievement and progress in the research on reconfigurable antenna since 2001, in Computational Electromagnetics Laboratory （CEMLAB） at University of Electronic Science and Technology of China （UESTC）. Several typical reconfigurable antennas are introduced, which can realize frequency, pattern or frequency-pattern reconfigurability by electrically controlling methods. Some techniques involved in the design and analysis of reconfigurable antennas are reported. At last, the development trend of reconfigurable antenna is predicted in the conclusions.     

一种宽轴比带宽L频段圆极化贴片天线

圆极化全向天线由于其自身的性能特点,在现代无线应用中越来越受到广泛的关注。提出一种宽轴比带宽的L频段圆极化微波贴片天线,该天线有上下两个介质层,下层微带馈线耦合馈电,接地面蚀刻十字交叉缝隙以帮助实现圆极化和改善上层贴片的耦合度。设计结果显示,该天线3dB轴比带宽可以达到3．5％（1.0231．060GHz）,在有效带宽内天线增益高于5．68dBi,在中心频率点（1．04GHz）天线的前后瓣比高于20dB。     

Patch antennas with switchable slots (PASS) in wireless communications: concepts, designs, and applications

This feature article describes, in a comprehensive and unified fashion, the authors' work on the development of novel kinds of reconfigurable microstrip antennas: patch antennas with switchable slots (PASS). PASS are versatile for wireless communication systems, and their structure is very simple. This article introduces the operational mechanism of PASS, as well as their frequency-ratio control and input impedance tuning. Various PASS designs are presented to demonstrate the capability of PASS in wireless communication. These designs demonstrate the functions of dual-frequency operation, dual-band circular-polarization performance, and circular-polarization diversity with only one layer and a single feed. A practical PASS application for future Mars rover missions is also highlighted: a compact, dual-band, circularly polarized antenna for the UHF band was designed, fabricated, and measured, based on the PASS concept.     

微带可重构天线的初步探讨

引入了一种崭新的天线概念-可重构天线。首先根据传统微带天线腔模理论定性地分析了微带可重构天线的工作机理，然后用时域有限差分（FDTD）法对微带天线的可重构特性进行了仿真分析。仿真和分析表明，矩形微带可重构天线当某一边长大于等于一个工作波长时，能够获得良好的可重构特性。     

Development of a Reconfigurable and Miniaturized CPW Antenna for Selective and Wideband Communication

The Planar microwave antennas with simultaneously selectively narrowband and wideband resonance characteristics are essential for the diversity applications. The paper presents modeling, fabrication and experimental verification of a coplanar waveguide excited antenna with a complementary patch which exhibits a narrow-band resonance at 2.47 GHz, and a wideband resonance between 5.52 and 11 GHz. A reconfigurability in the antenna design was achieved by placing a PIN diode across the slot position, and the wideband resonance was switched to the narrowband resonance with a center frequency of 9.56 GHz. The device was fabricated on a foam-based substrate of relative permittivity ε _r  = 2.2 and loss factor tanδ = 0.007. The tested antenna shows a comparable matching with the simulated results and a superior performance over the other reported reconfigurable CPW antennas was achieved.

     

一种新型圆极化可重构天线

本文利用最大功率传输效率法(MMPTE),通过4个相同左旋圆极化贴片单元作为子阵来实现阵列天线圆极化可重构.通过在被设计阵列(作为发射阵列)远场区引入极化控制接收天线,可以将整个收发系统看作一个无线功率传输系统,这样就可以把阵列天线的设计问题转换为一个天线之间的传输效率最优化的问题.通过调节接收天线的极化方式和接收位置...     

Social Spider Optimized Design Configuration of Multiband Reconfigurable Antenna for 5G Applications

Reconfigurable antennas receive more attention for many application due to their special characteristics like polarization diversity, multi band function and steerable diversity. However, reconfigurable antennas are capable of providing single and multiple reconfigurability. Nowadays, there is an increasing demand for multi-service radios for various spectrum standards. Many exiting works have been discussed about the enhancement of multi-band operation in reconfigurable antenna design. Most of them exhibit huge design complexity with high-cost consumption during the design optimization process. Thus, the proposed work uses Social Spider Algorithm for optimizing the design configuration of the reconfigurable antenna. Similarly, the band pass filter used at the feed line of the proposed antenna structure to easily achieve multi-band operation. The proposed design developed in ANSYS HFSS implementation platform and result analysis is performed in terms of bandwidth, VSWR, return loss, radiation pattern, gain, and directivity. The proposed reconfigurable antenna structure achieves 26.75 GHz bandwidth with 9.9 dB total gain and 8.8 dB directivity when comparing with existing works. Thus, the proposed antenna design suitable for 5G application applications by providing multi-band operation like WLAN, UWB, and Wi-Fi.

     

Integratable wide-band dual polarized antennas with rear field cancellation

Two variations of an integratable coplanar waveguide fed aperture stacked patch antenna are presented, which are capable of generating wideband dual polarized radiation. One of the antennas displays the desired characteristics for reducing polarization loss between an antenna remote unit (ARU) and mobile units at arbitrary angles. The other has a dual input structure and low cross-polarization useful for polarization diversity applications, or it can also produce circular polarization with the addition of a 90/spl deg/ hybrid. Back radiation concerns are addressed with the use of reflector patch elements. Results indicate that the rear directed radiation of the two slot coupled printed antennas mounted on small ground planes can be reduced across a wide bandwidth with the addition of a reflector element.     

共面耦合馈电小型化E-E形及半E-E形宽带微带天线

提出并设计了一种可应用于多频段无线通信的小型化宽带微带贴片天线.天线采用共面容性耦合的馈电方式补偿探针的分布电感,应用FR4高频介质板与空气层组成的层叠介质、E-E形和半E-E形辐射贴片缩减天线的尺寸.结果表明,E-E形微带天线和半E-E形微带天线的阻抗带宽分别为1.85～2.57 GHz(相对带宽32.6％)和1.85～2.50 GHz(相对带宽29.9％).和普通E形微带天线相比,E-E形和半E-E形微带天线的贴片面积缩小了47％和61％.