一种具有陷波特性的小型化超宽带天线

设计一种具有陷波特性的小型化超宽带印刷天线,通过在贴片上添加L型缝隙,在中心频率3.5GHz处,天线的回波特性产生陷波特性。天线的辐射贴片为梯形结合半圆形结构。天线的地板增加凹槽和切角,实现良好的阻抗匹配。该天线具有结构紧凑和形状简单的特点,并且在尺寸上较以往同类型天线有所减小,因此更易于加工和集成。最终实际制作天线样品,并进行测试,实测数据与仿真结果吻合良好。通带内天线辐射效果良好,并在在陷波频段达到陷波抑制的效果。     

陷波可重构的超宽带单极天线设计

本文提出了一个陷波可重构的超宽带单极天线.为了实现超宽带,辐射单元采用阶梯式结构.在辐射单元刻蚀一个开口缝隙,并在缝隙的适当位置放置三个开关,通过控制开关的不同组合状态实现陷波可重构.天线的尺寸为30mm×22mm(0.42λg×0.31λg,λg为低频导波波长).仿真和测量结果表明:天线可以工作在超宽带以及3个陷波可重构频段,超宽带工作频带为3.1GHz~10.7GHz,陷波频段涵盖3.4GHz~3.69GHz,3.7GHz~4.2GHz和5.2GHz~5.875GHz.     

加载高阻抗表面结构的超宽带陷波天线设计

本文设计了一种新型超宽带陷波天线.在超宽带微带单极子天线馈线两侧加载高阻抗表面单元,获得WiMAX频段陷波.在高阻抗表面单元上蚀刻阿基米德螺旋结构缝隙,使得单元尺寸比传统结构减小了55.2%.为了进一步在WLAN和WiMAX频段实现双陷波,将非对称的新型高阻抗表面单元加载至微带单极子天线馈线双侧.加工制作天线实物并进行测试,实测结果与仿真结果吻合良好,证明了该新型陷波单元的可行性.     

基于交叉缝隙的陷波可重构超宽带天线

本文设计了一种基于交叉缝隙的陷波可重构超宽带天线.通过采用3×3圆形超表面,有效拓展了天线的工作带宽.通过在矩形接地面上刻蚀两组交叉缝隙,并控制缝隙中设置的二极管的通断实现了天线的陷波可重构.所设计的天线尺寸较小,控制方式简单.结果表明,所设计的天线可以工作在超宽带和陷波模式下,超宽带模式的-10 dB带宽为3.5 G...     

一种双面超宽带双陷波天线

近年来,随着超宽带通信技术的不断成熟,超宽带天线的应用愈加广泛.为了有效的滤除WiMAX和X波段信号对超宽带天线产生的电磁干扰,研制了一种基于CSRR结构的新型双面超宽带双陷波天线.新型天线的主体结构是材质为FR微波介质的基板,通过蚀刻双面覆铜的FR微波介质的方法进行制作.与传统天线相比,该天线结构紧凑,尺寸较小,不仅...     

利用科赫分形解耦的四端口紧凑型QSC UWB MIMO天线

提出一种利用共面波导(Coplanar Waveguide, CPW)馈电的四端口紧凑型准自互补(Quasi-self-complementary, QSC)超宽带(Ultra-Wideband, UWB)多输入多输出(Multiple-input Multiple-output, MIMO)天线。此UWB MIMO天线的整体尺寸为40 mm×30 mm×0.8 mm,由4个六边形准自互补辐射单元对称排列而成,印刷在介质板的一侧。介质板另一侧印刷科赫分形解耦枝节和新型正六边形双开口谐振环(double-split ring resonator, DSRR)阵列,分别提升低频和高频处天线单元间的隔离度。实验与测试结果表明,此天线的工作带宽为3.1 GHz～15.5 GHz,在大部分工作频段内,隔离度达到20 dB以上。此外,天线在整个工作频带内具有良好的辐射特性和稳定的增益。包络相关系数小于0.04,表明该天线能够很好地满足极化分集特性,可用于便携式UWB MIMO无线通信系统。     

一种改善超宽带MIMO天线隔离性能的方法

多输入多输出(Multiple-InputMultiple-Output,MIMO)技术是现代通信技术的发展趋势,为移动通信的迅速更迭提供了极大支持.设计了一种二端口的超宽带MIMO天线,其-10 dB阻抗带宽从3.3 GHz扩展到9.1 GHz.通过在天线接地板上蚀刻一条宽缝隙,并在其中添加音叉型枝节,改善了超宽带M...     

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。     

一种新型双极化基站天线系统的设计与分析

随着现代通信技术的不断发展，在基站天线系统设计上逐渐采用双极化的方式。本文主要是对双极化基站天线进行研究，研发出了一种新型的宽频带双极化基站天线，评对其进行了模拟仿真。它因具有较宽的频带，同时它的带宽隔离效果好，还具有低交叉极化、性能稳定化、小型化的特点。众所周知，天线在我们的日常生活中起到了很大的作用，它可以接收无线电波系统发射的电磁波，同时也可以向外发射电磁波，因此，天线性能的好坏决定了整个通信系统是否能正常工作。     

一种低交叉极化小口径超宽带天线的设计

在高精度近场法天线测量、平面波发生器应用等场合,工作频段通常受限于近场探头。为了克服开口波导探头的带宽限制,出现了基于Vivaldi天线的超宽带、小口径天线作为近场探头。然而,常见的Vivaldi天线是非对称结构,导致交叉极化性能较差。设计了一款低交叉极化小口径超宽带天线,采用5层对称结构改进了传统Vivaldi天线的非对称性,利用贝塞尔曲线设计渐变槽辐射结构、加载电阻和贴片以及刻蚀矩形斜槽,减小了交叉极化比和天线驻波,改善了天线辐射方向性图。该探头口径宽70 mm、长201 mm,在0.9～6 GHz频段内天线仿真所得交叉极化比优于40.9 dB,增益为-5.5～9.53 dBi,端口反射系数幅度低于-10 dB,其辐射方向性图在全频段不开裂、主波束指向不变。     

A Compact Rhombus Shaped Antenna with Extended Stubs for Ultra-Wideband Applications

Ultra-wideband (UWB) is highly preferred for short distance communication. As a result of this significance, this project targets the design of a compact UWB antennas. This paper describes a printed UWB rhombus-shaped antenna with a partial ground plane. To achieve wideband response, two stubs and a notch are incorporated at both sides of the rhombus design and ground plane respectively. To excite the antenna, a simple microstrip feed line is employed. The suggested antenna is built on a 1.6 mm thick FR4 substrate. The proposed design is very compact with overall electrical size of 0.18λ × 0.25λ (14 × 18 mm²). The rhombus shaped antenna covers frequency ranging from 3.5 to 11 GHz with 7.5 GHz impedance bandwidth. The proposed design simulated and measured bandwidths are 83.33% and 80%, respectively. Radiation pattern in terms of E-field and H-field are discussed at 4, 5.5 and 10 GHz respectively. The proposed design has 65% radiation efficiency and 1.5 dBi peak gain. The proposed design is simulated in CST (Computer Simulation Technology) simulator and the simulated design is fabricated for the measured results. The simulated and measured findings are in close resemblance. The obtained results confirm the application of the proposed design for the ultra-wide band applications.     

Complex Permittivity of Planar Building Materials Measured With an Ultra-Wideband Free-Field Antenna Measurement System

Building materials are often incorporated into complex, multilayer macrostructures that are simply not amenable to measurements using coax or waveguide sample holders. In response to this, we developed an ultra-wideband (UWB) free-field measurement system. This measurement system uses a ground-plane-based system and two TEM half-horn antennas to transmit and receive the RF signal. The material samples are placed between the antennas, and reflection and transmission measurements made. Digital signal processing techniques are then applied to minimize environmental and systematic effects. The processed data are compared to a plane-wave model to extract the material properties with optimization software based on genetic algorithms.     

基于双谐振环超表面的双波束天线

本文提出了一种基于双谐振环超表面的双波束天线.天线由两个相同的印刷偶极子贴片和超表面构成,超表面单元为双谐振环.该天线通过加载超表面实现了波束成形和波束偏转;同时,通过在偶极子贴片辐射臂旁边加入一排短路过孔,抑制了旁瓣,增加了波束的偏斜角度,还使天线的波束宽度变窄.另外,在基板上加载2×2的双谐振环阵列,提高了天线的增益.结果表明,天线谐振频率在3.5 GHz,-10 dB带宽为0.93 GHz,最大辐射波束指向(φ,θ)=(±155°, 90°),增益可达到8.02 dBi.     

Advance Artificial Intelligence Technique for Designing Double T-Shaped Monopole Antenna

Machine learning (ML) has taken the world by a tornado with its prevalent applications in automating ordinary tasks and using turbulent insights throughout scientific research and design strolls. ML is a massive area within artificial intelligence (AI) that focuses on obtaining valuable information out of data, explaining why ML has often been related to stats and data science. An advanced meta-heuristic optimization algorithm is proposed in this work for the optimization problem of antenna architecture design. The algorithm is designed, depending on the hybrid between the Sine Cosine Algorithm (SCA) and the Grey Wolf Optimizer (GWO), to train neural network-based Multilayer Perceptron (MLP). The proposed optimization algorithm is a practical, versatile, and trustworthy platform to recognize the design parameters in an optimal way for an endorsement double T-shaped monopole antenna. The proposed algorithm likewise shows a comparative and statistical analysis by different curves in addition to the ANOVA and T-Test. It offers the superiority and validation stability evaluation of the predicted results to verify the procedures’ accuracy.     

新型复合钙钛矿Ba(SbⅢ,SbⅤ)O3的水热合成和表征

采用水热晶化法制备了Ｂａ（Ｓｂ＾Ⅲ,Ｓｂ＾Ⅴ）Ｏ３新型钙钛矿型氧化物,并通过ＸＲＣＤ、ＩＲ、ＳＥＭ和ＩＣＰ等方法对产物物相、形貌和组成等进行了表征,结果表明,产物为立方钙钛矿结构。晶肽参数为ａ＝０．４１５ｎｍ,粒度为１￣２μｍ具有一定团聚的多晶粉末,产物中锑为三价和五价两种价态,水热条件对合成影响的研究结果表明,Ｂａ（Ｓｂ＾Ⅲ,Ｓｂ＾Ⅴ）Ｏ３合成的适宜碱度和ｎｓｂ（Ｖ）／ｎＳｂ（Ⅲ）分别为８￣１０     

小型化超宽带微带天线的设计

本文提出了一种结构简单的小型化超宽带微带天线,尺寸为28mm×30mm．天线采用渐变馈线对酒杯状贴片馈电,接地板采用缺陷地的结构．天线参数采用电磁仿真软件CST进行仿真和优化．测量结果显示该天线在S11小于-10dB时,相对带宽是170．1％（2．4GHz～30GHz）．实际制作了天线的样品并进行了测试,实测与仿真吻合良好．     

A Novel Broadband Microstrip Antenna Based on Operation of Multi-Resonant Modes

A novel broadband microstrip antenna under operation of TM_1/2,0, TM₁₀ and TM₁₂ modes through a shorting wall and slots is proposed in this paper. Initially, an inverted U-shaped slot is adopted around the feeding point, which achieves a good impedance matching on TM₁₀ mode and separates the patch into two parts. Additionally, a shorting wall is added underneath the edge of smaller patch to excite another one-quarter resonant mode, i.e., TM_1/2,0 mode of smaller patch close to TM₁₀ mode to expand the impedance bandwidth. Further, the antenna width is enlarged and two symmetrical vertical rectangular slots are cut on the patch to reduce the frequency of TM₁₂ mode to form a broadband. Based on the arrangements above, a wide impedance bandwidth with three minima can finally be achieved. The results show that the impedance bandwidth of proposed antenna for |S11|<-10 dB is extended to 26.5% (23.5-30.67 GHz), which is three times of the conventional antenna at same profile. Moreover, a stable radiation pattern at broadside direction is realized over the operating band.