A high-gain 58-GHz box-horn array antenna with suppressed gratinglobes

A low-profile high-gain antenna array of box horns for the frequency band 57.2-58.2 GHz is presented. The antenna consists of 256 radiating elements divided into two subgroups of 128 elements fed by a rectangular waveguide feed network. The radiating elements are fed in parallel and the waveguides are connected with T-junctions. The matching of the T-junctions is improved with a matching pin and a splitter. Because of the waveguide feed network, the element spacing is larger than one wavelength, which causes grating lobes. The grating lobes and sidelobes in the H-plane have been suppressed by the use of a combination of subarrays, a special characteristic of the box horn, and an array amplitude tapering. The measured sidelobe levels in the H-plane are below -30 dB at angles larger than 8° from boresight. A gain higher than 35.7 dBi and a return loss higher than 14.4 dB have been measured for the antenna over the band 57.2-58.2 GHz     

一种空气同轴馈电的X波段低副瓣阵列天线

设计了一种应用于雷达系统中的低成本低副瓣阵列天线, 该天线阵包含256个辐射单元, 由四个64单元的子阵组成, 采用波导合成网络进行功率合成.天线单元采用空气同轴馈电的角锥喇叭, 空气同轴馈线内外导体呈方型结构, 其终端为短路馈电方式, 实现了内导体的自支撑设计和较低的传输损耗, 并依据综合幅度分布采用若干数量的不等功分器进行低副瓣设计.测试结果表明, 小于2的驻波带宽为0.5 GHz, 相对带宽为7.5%.另外, 中心频率的增益为30 dB, 增益大于29.5 dB的带宽为0.2 GHz, E面和H面的旁瓣电平为28.5 dB和29 dB.     

Source primaire multi-éléments et matrice de commutation associée pour satellite de télécommunication utilisé en mode AMRT

This paper describes a 12 GHz primary feed system designed for a scanning spot-beam transmitting antenna system operated in time-division multiple access (tdma) mode. The feed is made of three main parts: a radiating cluster consisting of seven horn elements, apin diode switch device which performs electronic scanning of the beam by successively activating the seven radiating elements, arf sensing waveguide network. The antenna system features are designed to optimize the gain throughout the coverage. A minimum directivity above 46 dB (without considering power losses due to the switch device) in a 1.35° coverage (corresponding to France) is expected from measured characteristics of the primary feed. This is corresponding at a 4 to 5 dB improvement upon a global beam system.     

Long backfire antenna with insular image guide feed for dual frequency operation

A long backfire antenna using an insular image waveguide feed compatible with microwave dielectric integrated circuit technology is presented. The antenna operates as a backfire component from 9.7 to 9.9 GHz and as an endfire antenna from 8.9 to 9.9 GHz, with symmetrical radiation patterns and low crosspolarisation. The important parameters of the antenna are experimentally optimised to give a maximum gain of 20 dB and 17 dB when working as a backfire and endfire antenna, respectively. This type of antenna can find extensive applications at millimetre-wave frequencies.     

A magnetic current loop array in a reflector antenna

A magnetic current loop antenna array is designed, implemented, and measured. Radiation pattern, input impedance, and efficiency of the array are presented. The array is intended as a feed in a reflector antenna. Using a 360 mm solid dish, the overall gain of the reflector antenna is 24.6 dB at 9 GHz. The tolerance in placing the feed at the focal point of the dish is high. The present feed is low cost, self-supportive, robust, and easy to manufacture. It is an ideal substitute for the horn in a TVRO or VSAT antenna     

一种K频段宽带双极化滤波喇叭天线设计

文中设计了一种K频段宽带双极化滤波喇叭天线,该天线采用阶梯型喇叭代替传统喇叭提升了天线效率,并通过在馈电波导冗余空间中引入一种T/Π型滤波结构,提升了天线带外的抗干扰能力. 仿真和实验结果表明,该双极化天线的?10 dB阻抗带宽超过5 GHz,覆盖了K/Ka频段卫星的下行频段,天线效率超过58%,并在其上行频段实现了超过33.1 dB的带外抑制,该天线可作为单元用于K/Ka频段卫星下行频段的大型阵列天线设计.     

宽带毫米波全向天线研究

介绍了一种宽带毫米波不对称双锥喇叭全向天线。采用脊波导－同轴线过渡结构馈电网络，既解决了毫米波段双锥喇叭的电问题，又满足了天线输入端口必须为波导形式的实际工程要求。测试结果表明在２６－４０ＧＨｚ频带内，天线的全方向性和输入皮比均满足设计要求。     

60-GHz CPW-fed post-supported patch antenna using micromachining technology

A 60-GHz coplanar waveguide (CPW)-fed post-supported patch antenna is presented using micromachining technology. In the proposed structure, the radiating patch and the feed line network can be optimized separately with a substrate. The antenna performance is improved by elevating the patch in the air. A patch array antenna is also designed with a simple feed network. The fabricated antenna shows broad band characteristics such as -10 dB bandwidth of 4.3GHz from 58.7GHz to 64.5GHz in the single patch antenna and 8.7GHz from 56.3GHz to 65GHz in 2/spl times/1 patch array antenna.     

Integrated terahertz TEM horn antenna

A terahertz transverse electromagnetic horn antenna (THz-TEMHA) monolithically integrated on a gallium arsenide substrate has been studied by means of subpicosecond pulses generated and measured on a 50 Omega coplanar waveguide. The measured reflection coefficient is below -10 dB from 100 GHz to about 1 THz. A terahertz ranging experiment was carried out in a monostatic configuration     

毫米波车地通信的小型化波导螺旋阵列天线设计

高速磁浮列车毫米波车地通信系统要求其车载天线具有小型化、宽频带、圆极化和辐射扇形波束等特点。为更好地满足这些要求,设计一种中心馈电的小型化波导螺旋阵列天线。该天线馈电系统采用同轴波导中心馈电、4路矩形波导并馈的形式,通过改变馈电波导尺寸、耦合探针长度以及末端采用波导同轴转换器等形式,实现了所有单元的等幅馈电;天线单元由低剖面螺旋天线构成,采用顺序旋转技术改善天线的圆极化性能。利用全波电磁仿真软件设计了一款中心频率为38 GHz的28单元波导螺旋阵列天线,并进行了实验测试。测试结果表明：在37~39 GHz频带范围内,天线驻波比小于1.41,增益大于21.7 dB,轴比小于3.6 dB,俯仰面波瓣宽度为4.5°~4.7°,方位面波瓣宽度为29°~29.7°,满足毫米波车地通信系统车载天线的设计需求。     

A planar subharmonically-pumped 71 GHz receiver with integral feed antenna

A planar, subharmonically-pumped, hybrid millimeter-wave receiver with integral antenna is described. Coplanar waveguide filters are used to isolate the ports and provide image enhancement. The integral planar antenna has 12 dB gain and is suited for use as a feed. The main lobe is normal to the substrate surface. The receiver is designed for an instantaneous bandwidth of 10 GHz. Experiments at 71 GHz indicate single-sideband mixer conversion loss of 6.5 dB. We believe that this represents the highest level of integration yet demonstrated in this frequency range.     

Low-profile microwave lens antenna based on isotropic Huygens' metasurfaces

An isotropic electromagnetic (EM) lens based on Huygens' metasurface is proposed for 28.0 GHz lens antenna design. The lens consists of a series of non-resonant and subwavelength metallic patterns etched on both sides of an ultrathin dielectric substrate. Both electric and magnetic responses are introduced to realize desired abrupt phase change and high-efficiency transmission for the secondary wavelets in the incident wavefront. Then, a substrate-integrated waveguide (SIW) fed patch antenna is combined with the lens as the primary feed to form a low-profile lens antenna system. The simulated and measured results coincide with each other, and demonstrate that the prototype realizes 8.8 dB～12.6 dB gain increment and low side-lobe levels over the bandwidth of 26.7 GHz～30.0 GHz. The novel design leads to a low-profile, light weight, and low-cost antenna solution in a wireless communication system.     

Investigation of the characteristics of low-cost and lightweight horn array antennas with novel monolithic waveguide feeding networks

3D printed X-Ku band single horn antenna and 2 × 1 and 2 × 2 pyramidal horn array antennas with novel lightweight and monolithic waveguide feeding networks (WFNs) are proposed at 10–15 GHz for satellite communications and radar systems to increase the gain. Proposed novel fabrication method consists of two main steps that are to make the skeleton of horn array antenna from acrylonitrile butadiene styrene (ABS) thermoplastic via 3D printer and to perform copper plating over all surface of antenna by using the electroless plating and electroplating processes. The WFN structures with 3λ element spacing designed and realized by using WR75 waveguide T-junction, E-type bend, and UDR 120 flange. Qualitative agreement between measurement and simulation via CST Microwave Studio is obtained with max 1 dB due to high precision and surface roughness. The gains of array antennas are increased by about 1.5 dB and 3 dB, respectively compared to the single antenna. VSWRs of array antennas are 0.3 dB and 0.6 dB, respectively higher than the single one. In the study, proposed 3D printed components not only with 90% lighter weight than, but also with 80% cheaper than commercial products, and horn arrays with -40 dB cross-polarization values.     

一种超宽带多模喇叭的设计

采用模式匹配法结合优化算法，为新疆天文台110 m天线研制出一种工作频带为4~12 GHz的三倍频多模喇叭.该喇叭由225个圆波导台阶组成，除了加工制造易于实现之外，与常规多模喇叭以及波纹喇叭相比，最突出的优点是在超宽频带内具有等化的辐射方向图，非常适合用作超宽频带射电天文观测天线的高效率馈源或者用于其他需要超宽频带设计的天线.     

共面波导馈电蝶形开口振子缝隙天线

讨论了共面波导(CPW)馈电蝶形开口振子缝隙天线。在缝隙振子天线两端加入蝶形开口结构,形成振子蝶形组合结构天线。使用有限元仿真软件(Ansoft HFSS)分析了设计的天线,结果表明组合结构天线具有振子天线与蝶形天线的优点:蝶形天线的宽带特性与振子天线的高增益特性,整个天线的性能得到提高。使用了两种馈电方式:感性耦合和容性耦合,感性耦合时组合天线的带宽特性较好,从振子天线5.9%提高到10.32%;容性耦合时增益特性较好,从振子天线的3.19dB提高至6.27dB。分析了衬底厚度对天线的影响,衬底厚度的增加使谐振频率降低,但对天线带宽的影响不大。     

Single-Layer Waveguide Feed for Uniform Plane TEM-Wave in Oversized-Rectangular Waveguide With Hard-Surface Sidewalls

A new single-layer waveguide feed is presented for excitation of the dominant quasi-TEM mode in oversized-rectangular waveguide with hard-surface sidewalls. Coupling windows are cut on the narrow wall of the waveguide feed and are cascaded on the same layer as the oversized waveguide. The feed is compact in terms of the length compared to the conventional hard horns and inhomogenious transformers. This type of waveguide feed is useful for the uniform feeding of the oversized-rectangular waveguide slot-array antenna with installed hard-surface sidewalls. Excitation of the uniform plane wave in$4lambda_0$wide waveguide is confirmed by the measurements on 12 GHz band model. The ripple in amplitude is less than 3 dB and in phase less than 15$^circ$. The uniformity of the field distribution is preserved along the direction of the wave propagation. Presented waveguide feed has the 3-dB beamwidth of 12.5$^circ$which is 4.5$^circ$narrower than the one of the conventional waveguide feed. The bandwidth is 16.7% in terms of reflection less than$-$10 dB for the overall feeding structure.     

Asymmetric CPW-fed SRR patch antenna for WLAN/WiMAX applications

In this paper, a compact asymmetric coplanar waveguide (CPW) feed with split-ring resonator (SRR) is proposed to resonate at dual-band operations for wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) applications. The asymmetric CPW-fed SRR patch (ACSP) antenna consists of a meander line, square-shaped split ring, and CPW ground plane. The proposed ACSP antenna resonates at two operating frequencies, namely, 2.48 GHz (2.4–2.74 GHz) and 3.49 GHz (3.25–3.64 GHz) with reflection coefficients (S₁₁) of −16.65 dB and −32.67 dB, respectively. The measured results agree closely with the simulation results of the proposed antenna.     

L/S双频段圆形阵列单脉冲抛物面天线

该文研究了一种以六单元圆形阵列作为照射器的单脉冲抛物面天线,这种天线具有实现宽频带跟踪的独特优点,其输出信号类似于圆波导单口径多模馈源,具有一个和波束,一个锥形差波束,并给出了没有接收机参与的情况下,将宽频带的和差两个通道变成单通道的途径。研制了一套L(1#61485;2GHz),S(2.2#61485;2.3GHz)宽频带双圆极化单通道单脉冲天线,对该天线的照射器、分波器、波束形成网络、单通道变换器等组件和馈源结构集成化设计进行比较详细的介绍。该馈源安装到一个3.2m的抛物面上,频率为1.1GHz,2.2GHz时,和波束增益分别为22.9dB,30.1dB;差波束零深为35dB,40dB。在L/S两个频段内跟踪稳定。     

W波段双极化单脉冲天线设计

为了探测目标的极化特性,研制了工作在W波段的双极化单脉冲卡塞格伦天线.天线由主反射面、副反射面、馈源喇叭、正交模耦合器及和差器组成.天线主反射面口径为137 mm,馈源为五喇叭形式,正交模耦合器采用渐变波导匹配方案,和差器通过平面型定向耦合结构实现.通过将馈源喇叭、正交模耦合器及和差器集成设计,减小了连接损耗,压缩了天线纵向尺寸.测试结果表明,天线驻波带宽约3. 7 GHz,极化隔离度优于35 dB,和波束增益大于37. 9 dBi,副瓣电平优于-15 dB,差波束零深优于-25 dB.天线在W波段实现了较好地双极化单脉冲性能.     

Design and fabrication of a wideband reflectarray antenna in Ku and K bands

The purpose of this paper is design of a wide band single layer reflectarray antenna using a new broadband cell. The proposed cell consists of two parts. The first part is a circular patch and the second one is a ring with some additional stubs, which are attached to the patch and ring in a symmetrical form. The circular patch and ring elements are designed at frequencies of 20 GHz and 15 GHz respectively. In order to increase the reflectarray antenna bandwidth, at first the dimensions of the patch, ring and stubs are optimized to attain uniform phase response in the frequency range from 11 GHz to 20 GHz. Then an air layer is considered under the dielectric substrate. The reflectarray antenna is designed based on this optimized wideband unit cell. A wideband horn antenna is also designed as a feed antenna for the proposed reflectarray structure. The reflectarray antenna with horn are simulated. The 1 dB gain-bandwidth of 4.66 GHz is obtained (27.4% fractional bandwidth) in the frequency band of 14.72 GHz to19.38 GHz. Finally, the reflectarray antenna is fabricated and tested. It can be seen that there is a good agreement between simulation and measurement results.