Design and experimental investigation of radiators for antenna arrays based on EBG waveguides

Problems of the design of a centimeter-band antenna array containing a multichannel power divider based on EBG waveguides and helical radiators are considered. The general configuration of such an array is proposed. The properties of this array and the requirements on the array elements are analyzed. Features of the design of two-channel and four-channel elementary power dividers forming the multichannel power divider are studied. The structure and the parameters of these devices are determined. The array input part is designed in the form of a coaxial-to-waveguide transition (CWT) with equal power division. The CWT characteristics obtained with the use of numerical simulation are compared with experimental data. The results of the experimental investigation of a 16-element thinned antenna array in the frequency band 8–10 GHz are presented.     

Design and experimental investigation of stripline antennas

The results of development and experimental investigation of several centimeter-wave planar antennas are presented. The antennas contain a multichannel stripline power divider and a 2D periodic array of slot radiators excited by symmetric strip lines. A single-polarization antenna, an antenna with two linear polarizations, and an antenna with two circular polarizations are analyzed. The results of measuring the basic parameters of these antennas (the gain, the radiation pattern, and the cross-polarization level) are presented. Specific features of the design of such antennas and possible means of improvement of their performance characteristics are discussed.     

A broad-band printed circuit hybrid ring power divider

The design of a broadband ring power divider that provides substantial improvement in coupling and phase characteristics over a wide frequency range compared to that of a conventional hybrid ring is presented. It is shown that the new power divider design can be easily constructed using realizable impedances and is applicable to both equal and unequal power divisions. Experimental verification of the broadband power divider was achieved in a stripline configuration at Ku-band for an equal power divider and a 3-dB power divider. Close agreement was observed between theoretical and experimental results for both of the power dividers. The usable bandwidth of the broadband power divider is approximately 45%. It is concluded that this broadband power divider is particularly suited for a narrowband low-sidelobe antenna array beam-forming network, for it provides substantially improved amplitude and phase characteristics, a requirement for low-sidelobe array antennas, and good isolation between output ports     

CPW无空气桥功分器设计及其在阵列天线中的应用

针对传统微带圆极化阵列天线存在带宽较窄、尺寸较大等问题,提出一种新颖的基于共面波导(CPW)槽线转换结构的无空气桥功分器,并基于此功分器设计了一款紧凑型高定向性圆极化阵列天线。设计的共面波导功分器利用共面波导奇模式方法实现了能量分配,不需使用空气桥结构及四分之一波长匹配线,因此尺寸更加紧凑,结构更加简单。利用此功分器设计的圆极化阵列天线剖面厚度仅为1 mm,轴比带宽为4.14%,阻抗带宽为7.03%;在5.8 GHz时,实测增益为8.412 dBi,在保证低剖面、小尺寸的同时,可提供足够的工作带宽以及天线增益。     

A Compact Two-dimensional Power Divider for a Dielectric Rod Antenna Array Based on Multimode Interference

In this work, multimode interference is investigated for the design of a two-dimensional fully dielectric power divider, well suited for the usage of dielectric waveguides. Most important, power division is achieved in a single device without the need of cascading multiple dividers. This allows to design a very compact and lightweight power divider, well applicable for dielectric rod antenna arrays. As a proof of concept for the used technique, a 16-way power divider with 4 × 4 output ports, made out of Rexolite, is realized, working in a frequency range between 90 and 105 GHz. For the S-parameter measurements, a special measurement setup, including a modular pin probe technique as well as radiation taper for waveguide termination, is proposed. The measurements are in good agreement with the simulations with a power split of ??15 dB for all output ports within the desired frequency range. This is equal to an additional insertion loss of 3 dB. To demonstrate the usability for antenna arrays, a fully dielectric rod antenna array is realized based on the proposed power divider. With this array, a gain of 22.5 dBi at 97.5 GHz was achieved.     

Design and experimental investigation of a multibeam integrated reflector antenna of the millimeter wave band

A multibeam integrated reflector antenna operating in the millimeter wave band is considered. The antenna consists of a radiating array, a planar mirror, and a multichannel feed. The results of simulation of a radiating array of slots in a metal screen are presented. The array is manufactured on the basis of a medium with forced refraction, including a double-slot array, which can radiate along the normal to the array plane. Operation of the array in the multibeam mode is analyzed. It is shown that application of a medium with forced refraction increases the array aperture efficiency in this mode. The results of the design of a planar two-layer mirror are presented and the mirror’s quality indices are estimated. A multichannel radiator designed as an array of planar H-plane horns is studied. The results of simulation of such a radiator with the help of an approximate technique and numerical solution of an electromagnetic problem are considered. The design of the multibeam antenna and its experimental characteristics are presented.     

幅度固定唯相位实现波束控制的功分器设计

针对传统阵列天线设计流程中功分器繁琐的设计过程, 基于满足-3 dB范围为0°~12°, -10 dB波束宽度为65°, 波束覆盖为65°, 中心频率为9.05 GHz的余割平方扩展波束赋形要求, 设计了一种幅度固定唯相位实现波束控制的新型串馈结构Gysel功分器.该功分器幅度为固定值, 此幅度分布满足余割平方赋形阵列天线幅度的分布特征, 在遗传算法计算出理想赋形激励后只需调整该功分器的输出相位值就能实现高拟合度的余割平方扩展波束赋形, 大为减少了传统设计中功分器所需的设计时间.     

一种微带线高隔离度功分器的设计

在功分器设计中,随着频率的升高,输出端口的隔离度会变差,使系统性能下降。应某课题的需求,利用微 带传输线的特性,仿真设计了一种具有高隔离度的Ku 频段威尔金森功分器,设计原理是通过在输出臂适当增加微带线, 同时引入隔离电阻实现输出端口匹配。将此功分器应用到阵列天线的馈电系统,子天线间端口隔离度变大,仿真结果 能达到-40dB,能够满足应用需求,提升了阵列天线系统的性能。     

A millimeter-band planar lens based on an inhomogeneous medium with forced refraction

A millimeter-band planar lens designed on the basis of an inhomogeneous medium with forced refraction, which is formed by a periodic grating of metal strips placed on the surfaces of a dielectric plate, is considered. The possibility of application of this lens as the basis for the design of a multibeam receiving antenna for a radio imaging system is analyzed. The structure of an antenna consisting of a planar lens and a multichannel feed is proposed. The results of the design of a planar lens based on an inhomogeneous medium with forced refraction are presented. A multichannel feed in the form of an array of E-plane horns is analyzed and the results of simulation of this feed with the help of an approximate technique and numerical solution of an electromagnetic problem are given. The design of the multibeam antenna and its experimental characteristics are presented. The possibility of computer correction of radiation patterns of the multibeam antenna is considered.     

抑制共模噪声的SIW 平衡馈电差分缝隙天线阵*

提出一种利用差分天线在共模激励和差模激励下方向图不同来抑制共模噪声的方法,并基于该理论 设计了6×6 平衡馈电差分SIW 缝隙天线阵进行验证。该天线由6个宽边纵向SIW 缝隙天线子阵列组成。辐射缝隙 被设计为只在差模激励下辐射,达到抑制共模信号的目的。每个天线子阵采用平衡差分馈电方式,使用两个1分6 梳状功分器将6个子阵同时激励。整个天线使用标准PCB 工艺加工,为了测试共模和差模激励,分别设计了带有 180°相移的功分器和T型功分器用来生成差模和共模信号。在差模激励下,天线的最大增益为20.2dBi,S11幅值小 于-10dB 带宽为7.2%(39.6 ~43.8GHz),在共模激励下天线的最大增益为10.1dBi,在整个工作频段内S11幅值大于 -7dB。仿真和实验结果验证了该结构的SIW 缝隙天线对差模信号能够有效地辐射而对共模信号进行抑制。     

X波段低副瓣阵列天线研制

为了满足雷达系统对阵列天线低副瓣的要求,设计了1个工作在X波段,相对带宽为10%的一分九十六大型带状线功分网络,利用仿真软件优化设计,在频带范围内天线驻波小于1.5,副瓣在-35dB以下,满足指标要求。     

低副瓣基片集成波导缝隙阵圆极化天线

基于基片集成波导技术与标准印刷电路板工艺,实现了圆极化、低副瓣的平面缝隙天线阵列.辐射单元采用基片集成波导项层匹配缝隙对结构,行波式圆极化单元.辐射缝隙经过改进,单个辐射单元的反射系数均小于-30 dB.平面阵列采用基片集成波导低副瓣功分器馈电.文中给出了具体设计公式、方法和仿真结果.设计制作的16×16阵列在16.1 GHz频点上实测增益为30 dB,轴比为0.7 dB,副瓣小于-20 dB.     

Compact Corporate Power DividerUsing Metamaterial NRI-TLCoupled-Line Couplers

A low-loss, planar and compact metamaterial 1:4 corporate power divider design is presented. The power divider uses a cascade of three microstrip/negative-refractive-index transmission-line coupled-line couplers allowing it to be compact in the longitudinal direction. The fabricated prototype operates at 2.10 GHz and is 11.6 cm wide-designed for feeding a four-element patch antenna array. The 3 dB transmission bandwidth ranges from 0.73 GHz to 0.46 GHz for the various ports with a total insertion loss of 1.1 dB, good phase balance and better than 20 dB isolation among the output ports.     

一种毫米波微带双频天线阵的设计

文章阐述了利用3个T型功分器设计一个4×1的毫米波微带双频并馈天线阵方案,该双频天线阵的中心频率在32 GHz和35.36 GHz左右,运用Ansoft HFSS软件进行仿真测试,天线阵的增益方向图说明该天线阵主要的辐射方向是上半空,天线阵在32 GHz的增益为12.62 dB,在35.36 GHz的增益为10.72 dB。     

Waveguide to microstrip line transition and power divider

A novel waveguide to microstrip line transition and power divider with a planar structure is presented. The transition and power divider is designed on both sides of a single layer dielectric substrate, and can be used as a feed of an array antenna with a waveguide feed structure or as a complete integration of waveguide components with active components such as MMIC. Experimental results are shown and compared with simulations; it is shown that good return and insertion loss characteristics are obtained for the K-band     

K频段微带线-波导腔混合型功分网络设计

高增益、宽带、高指向精度是有源相控阵天线的重要要求,功分网络的幅相分布、带宽、插损等直接影响相控阵天线的性能。设计了工作在K 频段、相对工作带宽超过25%的1分24 大型功率分配网络。采用基于微带线-波导腔混合技术的功率分配网络,抑制了高频空腔谐振,并使用HFSS 软件进行仿真,制作样件进行测试。测试结果表明,在要求工作带宽范围内,网络表现出优良的幅相一致性,端口驻波性能较好,且剖面低、结构紧凑、重量轻,能够满足机载、弹载等环境的应用要求。     

微带一分五宽带Wilkinson功分器的设计制作

针对功分器被应用于功率放大器、相控阵天线、混频器和多路中继通信机等微波设备中。其性能的好坏直接影响到整个系统能量的分配和合成效率。设计了一种工作频带在0.7～2.5 GHz的微带一分五宽带功分器,根据优化结果制作了器件实物。采用Ansoft Designer、Serenade以及HFSS软件进行协同仿真,仿真结果表明,该功分器在整个频带范围内具有良好的性能指标,器件测试结果与仿真结果吻合,适用于通信、功率分配合成系统中。     

一种新型布局的圆极化微带天线阵优化设计

提出了一款高增益低副瓣新型圆极化微带天线阵。单元天线采用叠层切角圆极化微带结构,通过八边形边界布局和顺序旋转交叠组阵技术,实现了天线阵方向性图的对称性和圆极化辐射性能的最优化;馈电网络采用威尔金森功分器和最大平坦式阻抗变换器实现不等功分宽带阻抗匹配,通过改进馈电方向寻求对称结构,简化了馈电网络的设计。制作了天线阵实物并进行了测量。测试结果表明:天线在3.2~4.6 GHz频段内S₁₁<-10 dB,阻抗相对带宽36%;在3.8~4.5 GHz频段内顶点轴比小于3 dB,圆极化相对带宽17%;在4~4.4 GHz频段内天线增益均在15 dB以上,最高增益达17 dB。     

一种圆形智能天线阵列与校正网络的设计

论述了一种用于智能天线系统的新型圆形天线阵列与校正网络的设计方法.设计了一种具有良好一致性和高增益全向特性的新型直排印刷振子天线结构,并采用奇偶模分析方法,实现了一种1:8威尔金森功分器/合路器与平行耦合线定向耦合器相结合的校正网络.实验结果证明,研究结果对于3G通信具有很高的实用价值.     

基于SSPPs的低剖面宽带八木天线阵列设计

提出了一种基于新型人工表面等离子体激元(Spoof Surface Plasmon Polaritons, SSPPs)馈电带有引向器的低剖面宽带八木天线阵列。天线阵列包括两部分:基于人工表面等离子体激元波导的四路宽带功分器和八木天线阵列。人工表面等离子体激元具有高的场局限性,将信号束缚在人工表面等离子体激元的凹槽结构中保证了信号的高效传输,减少了传输损耗。八木天线通过进一步加载引向器结构能够实现端射辐射特性。测试结果表明:天线阵列的回波损耗在4.5 ~6.05 GHz 频率范围内小于-10 dB。天线阵列实际增益在4.5 ~ 6.05 GHz 范围内最高可达11.1 dBi。