两种不同类型天线抗衰落特性的比较

应用直径为３．２ｍ的抛物面天线和２０ｄＢ增益的矩形喇叭天线在两条水面电路上的传播测试，统计结果表明，直径为３．２ｍ的抛物面天线具有较好的克服反射衰落的效果。理论计算和实验结果是相一致的。     

Ka波段膜片加载曲线内壁矩形喇叭天线

介绍一种工作在Ka波段曲线内壁矩形喇叭天线,这种天线的辐射结构采用高斯曲线构成的曲面矩形喇叭,在曲面矩形喇叭口加载金属膜片,通过对天线参数的设计优化,在22.5～26.5 GHz频带上方向系数大于15 dB,驻波比优于1.8,E面方向上副瓣电平比主瓣低26 dB以上,对比标准增益角锥喇叭天线测试显示,膜片加载曲面喇叭体积小,改善了传统角锥喇叭的3 dB波束宽度,降低副瓣,结构简单,活动方便,可单做馈源亦可做反射面天线馈源。     

介质加载喇叭天线

一、引言为了获得旋转对称波束和极低的旁瓣,曾对双模喇叭,波纹喇叭和其他形式的喇叭进行了研究。喉部有陡峭的波导接合段的双模喇叭在很大程度上取决于频率。波纹喇叭在宽带范围内虽能保持良好的辐射方向图,但过于笨重难以制造。采用其他方法不是结构复杂就是体积庞大。作者发现,只要在喇叭内放置一薄的介质套,就能作出宽带的双模喇叭天线。本文讨论这种天线的原理,结构及所测得的辐射方向图。作为介质加载喇叭天线应用之一的一种赋形天线,文中也作     

内嵌异向介质平板透镜型喇叭天线特性研究

根据异向介质零折射特性,设计出一种平板结构的异向介质,由该异向介质构成了一种新型的透镜喇叭天线.利用CST Microwave Studio仿真软件优化设计出异向介质结构,并通过棱镜折射仿真实验验证了其零折射特性,然后将此结构嵌入到矩形喇叭天线口面上,对该天线的端口反射系数、辐射电场分布和增益等电磁特性进行了研究.研究结果表明:在16.10～17.20 GHz频段,异向介质透镜喇叭天线增益超过20 dB,比相同尺寸的未加异向介质常规喇叭天线提高2 dB以上,其口面利用系数可达0.60,定向性可与相同口径的最优喇叭相比,而纵向尺寸只有相同口径最优喇叭的56%,从而实现了喇叭天线小型化的目的.     

高增益金属透镜天线设计

金属透镜天线具有高增益和大功率容量等优点。采用几何光学原理将一组平行间隔的金属板设计为金属凹透镜,实现对电磁波的汇聚,获得高增益辐射特性。在辐射原理和结构分析基础上,设计了一款工作于X波段(10 GHz)的金属透镜天线,采用矩形喇叭天线作为初级馈源、13片金属板嵌于一只半径为153 mm的PVC筒顶部。仿真和测试结果吻合良好,表明该金属透镜天线性能优异:|S_(11)|<-10dB阻抗带宽为18%(从9.6~11.5 GHz),在10GHz工作频点的增益达到27dBi,相比喇叭天线提高了10.2dB。     

MMDS天线技术及其应用

近年来，由于我国有线电视的迅速发展，ＭＭＤＳ多路微波分配系统的传输与分配技术得到了广泛的应用。ＭＭＤＳ天线是ＭＭＤＳ系统的重要组成部分。为满足全方位、大范围内的区域覆盖或特定异形扇区覆盖或多点定向传输的需要，形成了各种全向和定向ＭＭＤＳ发射天线及接收天线。笔者通过对现有微波天线技术和工艺的分析发现，ＭＭＤＳ发射天线一般采用波导缝隙阵列式天线、圆柱形同轴振子阵列式天线、喇叭天线、抛物盒式天线等形式；ＭＭＤＳ接收天线多采用矩形栅状抛物面天线及圆形网状抛物面天线。这几种天线都具有电气性能好、结构简单、…     

一种应用于微波水分检测仪的角锥喇叭天线设计与分析

根据惠更新原理对比分析了几种常用喇叭天线的特性,依据角锥喇叭天线的设计理论,结合铁精矿水分微波检测仪的实际情况,设计了中心频率为9.4 GHz、增益大于10 dB的角锥喇叭天线结构.运用HFSS软件对该结构进行了仿真分析,通过仿真和对比分析得到一组较好满足工作需要的辐射增益方向图、驻波比等辐射特性,仿真结果验证了设计天线的可行性,为后期的试验和运行提供依据.     

多模反射面天线理论与技术研究

在卫星星座跟踪、远距离微波能传输等需要构建大功率均匀场的领域,都需要具有平顶波束的高增益反射面天线.受多模和混合模喇叭天线的启发,文中创新性地在反射面天线设计中引入了多模的理念.首先提出了双模反射面的思路,即在标准抛物面天线的最大辐射方向上引入相位差为180°的反相模式场,由两种模式合成平顶波束.然后,将双模的理念推广...     

一种用于毫米波双向通信的波导喇叭天线设计北大核心CSCD

毫米波由于方向性强，要实现在同一直线上的前后向通信，通常采用功分器+双天线的方式。为进一步实现集成化，本文提出了一款将波导功分器和双矩形波导喇叭天线进行集成设计的波导喇叭天线。首先，根据波导的两级阻抗变换设计T型宽带波导功分器；然后，根据最佳角锥天线公式完成对矩形喇叭天线设计仿真；最后，将波导功分器和双矩形形喇叭天线按工程应用进行集成设计建模仿真。仿真结果表明该双向天线最大增益为22.48dBi，在71-86GHz的频带内S11优于15dB。除此之外，本次设计的波导喇叭天线具有结构简单、尺寸小、加工容易等优点，通过合理地集成到宽带通信设备中，可满足货运铁路准线性区上下行的双向无线接入。     

一种改进型超宽带喇叭天线

基于TEM喇叭天线的结构特点,用两根弯曲的窄带代替基本模型中的上板,设计了一种飘带喇叭天线。该设计不仅有效地提高了天线的低频利用率,并且实现了天线的轻量化。通过对飘带结构进行进一步改进,利用AnsoftHFSS仿真软件对模型进行了分析。结果表明,改进后的飘带喇叭天线不但有较好的超宽带性能,而且其辐射性能也有了较大提高。...     

Ku band pattern reconfigurable substrate integrated waveguide leaky wave horn antenna

A dual band substrate integrated waveguide H plane sectoral horn antenna with reconfigurable radiation characteristics has been proposed in this paper. Designed antenna acts as a perfect broadside radiator at 16.1 GHz and perfect endfire radiator at 14.4 GHz frequency. Broadside radiation has been achieved by etching rectangular slots in the flared section of horn exhibiting a gain of 8.87 dBi. To achieve perfect endfire radiation, dielectric loading is done at the edge of horn and at this frequency antenna shows a gain of 11.3 dBi. The horn and the loaded dielectric are integrated by using the same single substrate resulting in easy fabrication and low cost. The proposed design has been fabricated and measured results are in good agreement with the simulated results.     

一种超宽带高增益的透镜喇叭天线的设计

该文提出了一种适用于微波通讯系统的超宽带(UWB)高增益透镜喇叭天线。该天线由一个E面喇叭天线,一个球面介质透镜和双楔形金属脊构成,并由同轴线馈电及采用HFSS软件仿真。仿真结果表明,双楔形金属脊可有效增加喇叭天线的带宽,有效频率带宽达到2～12 GHz。当仅使用双金属脊来改善喇叭天线的性能时,喇叭天线的增益会下降。文中使用一种球面介质透镜来补偿双金属脊对喇叭天线增益的负面影响。仿真结果表明,该透镜可有效提高喇叭天线在工作频带内的增益。采用透镜和金属脊结构后,该喇叭天线拥有超宽带,高增益和较强的定向辐射性能,可以应用于各类通信系统中。     

Rectangular backfire antenna with dielectric surface-wave structure

A rectangular backfire antenna with a dielectric surface-wave structure is studied experimentally and theoretically. It consists basically of two plane rectangular reflectors and a dielectric structure as a rectangular-waveguide prolongation. The antenna construction is compared with those of ordinary dielectric and horn antennas, which are more than twice the length of the backfire antenna. Simple expressions for the far-field radiation pattern are derived in terms of the near-field amplitude distribution.     

高增益Ka波段EBG天线阵列的设计

电磁带隙(EBG)天线是一种可以提高天线辐射口径及增益的新型天线,以FSS作为EBG反射面,角锥喇叭作为辐射源,设计了一种可以工作在29.7³0.2 GHz,最大增益为23 dB的EBG天线,并对7个喇叭阵列进行了仿真分析,证明了该种EBG天线具有良好的工作性能,可以作为小型化单口径反射面多波束天线的辐射源,用于减小通信卫星的重量。     

一种基于SIW技术的喇叭天线

设计了一种新型微带天线。天线印制板为基片集成波导结构,天线前端用金属过孔形成喇叭状,从而构成一种微带H面波导喇叭,通过微带线--波导转换结构进行馈电,在辐射主方向具有较高的增益。该天线集合了传统微带天线低剖面以及H面波导喇叭的集束、高增益的特性,最后应用Ansoft HFSS进行了设计和仿真,验证了设计的正确性。     

Minor lobe suppression in a rectangular horn antenna through the utilization of a high impedance choke flange

A significant reduction in the minor lobe radiation pattern of a rectangular pyramidal horn antenna is obtained by placing a choke around the aperture of the antenna and adjusting the choke to approximately a quarter wave in depth. The reduced minor lobe radiation means less scattering and a higher efficiency. The choke also results in an improvement in the antenna gain with a measurably narrower beam. A minor variation of approximately 10 percent, peak to peak, is obtained in the antenna input impedance for choke depths varying from zero to a quarter of a wave.     

Ultra-wideband antipodal slot antenna with improved radiation performance

A novel antipodal wide-slot antenna for ultra-wideband (UWB) applications is proposed and studied in detail. The antenna is fed by a microstrip line terminated with a rectangular tuning patch. An antipodal structure is employed to improve the radiation performances. The return losses, surface E-field, current distribution, radiation patterns and gains of the antenna are numerically and experimentally investigated. Results show that the proposed antipodal antenna has an impedance bandwidth from 0.79 to 4.0?GHz, which is about 5:1. Compared with conventional rectangular wide-slot antenna, more stable radiation pattern with lower cross-polarisation level and flatter gain variation over a 3:1 bandwidth can be obtained. Thus, the proposed antenna should be more suitable for future UWB-multiple-input multiple-output applications using polarisation diversity than conventional UWB rectangular slot antennas.     

Filtenna Consisting of Horn Antenna and Substrate Integrated Waveguide Cavity FSS

An integrated module with filtering and radiation performance realized by covering substrate integrated waveguide (SIW) cavity frequency selective surface (FSS) at aperture of horn antenna has been investigated in this paper. The module has functions of bandpass filter and horn antenna, so it is called a "filtering antenna" (filtenna). It is very suitable for applications in military platforms where FSS is used for antennas and radars' radar cross section (RCS) reduction. The filtenna is simulated and optimized with CST software and its performance is verified by experiments. From simulated and measured results it can be found that the proposed structure keeps characteristics of return loss, radiation pattern and gain of the horn antenna within desired frequency band, meanwhile presents effective reflection to interference signals at out-band. Using this structure the volume and cost of communication systems in military platforms can be effectively reduced     

Ka 波段EBG 天线阵列的仿真与分析

电磁带隙(EBG)天线是一种可以提高天线辐射口径及增益的新型天线,本文首先以FSS 结构作为EBG 反射面,角 锥喇叭作为辐射源,设计了一种可以工作在29.7-30.2GHz,最大增益为23dB 的EBG 天线;其次,研究了7 个喇叭构成六 边形阵列时的阵列特性;最后,将EBG 天线用作单反射面多波束天线的馈源研究了波束的覆盖特性,结果表明,当波束 大小为1.12°时,多波束天线的峰值增益为44.5dB,边缘交叠电平为40.4dB,载干比大于12dB。证明了这种EBG 天线 具有良好的工作性能,为将来小型化反射面多波束天线的设计提供了一种新的思路。     

A new multimode rectangular horn antenna generating a circularly polarized elliptical beam

A multimode circularly polarized rectangular horn antenna generating an elliptical shaped beam is described. This antenna operates in two orthogonal mode sets, namely the TE10+ TE/TM12and TE01+ TE/TM21modes. By virtue of the higher order TE/TM modes, the apertureE-field distribution can be tapered such that the effectiveE-plane far-field beam width is approximately equal to theH-plane beam width of the other orthogonal set of modes, resulting in low off-axis polarization axial ratio. Because of the tapered aperture distribution, the radiation patterns also have low sidelobes. The elliptical cross section beam is a direct result of the rectangular shaped aperture. This antenna, used in conjunction with a spacecraft to illuminate an elliptical zone on the earth surface, offers high edge-of-coverage gain, low sidelobes, low edge-of-coverage (EOC) axial ratio, less RF sensitivity to the space environment, and low cost. The performance of this antenna has been evaluated experimentally.