Ka频段双圆极化相控阵天线设计

设计了一个8×8的Ka频段双圆极化相控阵天线。该天线单元采用正交缝隙耦合馈电的多层贴片微带天线,并由一个小型化宽带3 d B枝节电桥实现双圆极化。为提高天线圆极化性能,依次旋转天线单元,形成2×2双圆极化天线子阵。以天线子阵为基础,扩展成8×8相控阵天线。HFSS仿真结果表明,天线在方位360°俯仰±60°范围内进行双圆极化扫描,轴比小于3 d B,且轴比带宽达30%。该研究结果可应用于卫星通信的双圆极化相控阵天线的设计。     

新型强耦合宽带双圆极化阵列天线

空间飞行器由于受到动力和负载的限制, 需要尽可能使搭载的天线轻质小型化.文中提出了一种新型强耦合双圆极化轻质天线.天线单元采用H型缝隙耦合和增加寄生贴片方法, 提高了天线带宽.同时, 通过在辐射贴片、寄生贴片上开圆形槽, 以及金属反射板栅格化的处理, 明显地减轻了天线的质量.采用这种新型天线单元, 设计了8单元的宽带双圆极化阵列天线.仿真结果表明:该阵列天线的中心频率为433 MHz, 左旋和右旋圆极化的相对轴比(Axial Ratio, AR)带宽(AR < 3 dB)分别达到了24.4%和23.2%, 有效实现了小型轻质化宽频带双圆极化阵列天线.     

非辐射边馈电的宽带双层微带贴片天线

介绍了一种非辐射边馈电的宽带双层微带贴片天线单元,并对其参数特性进行了仿真研究,结果表明,通过在寄生贴片上开3～5个与极化方向相平行的缝,可有效抑制天线的交叉极化,同时改善天线的阻抗带宽。相比传统双层微带贴片,该天线单元的阻抗带宽可提高3%以上,而交叉极化指标相当。当该单元应用于阵列天线设计时,可简化馈电网络,便于实现宽带、高效、大扫描角的微带共面馈电天线阵。对X波段8×8单元实验小阵的测试结果表明,该天线在17.6%的频段内具有良好的交叉极化性能及较高的工作效率。     

可收拢展开的宽带双圆极化柔性薄膜天线

星载相控阵雷达因其平台的特殊性要求其天线具有大型轻质、可收拢展开的特点。设计了一种可收拢展开的宽带双圆极化柔性薄膜天线。天线各层均采用柔性薄膜材料制作,相邻层间为空气,因此天线整体为柔性可收拢展开。采用两相互垂直的"H"形缝隙和双层微带贴片结构,并结合3 dB电桥实现了宽带和高隔离度的双圆极化。仿真和测试结果表明,该薄膜天线单元两馈电端口驻波小于2的相对带宽约为36%,极化隔离度大于32 dB,并给出了天线单元双圆极化波瓣方向图的测试结果,其3 dB波瓣宽度为64°,天线单元增益为6.2 dB,并设计了天线小阵。     

一种卫星移动通信双极化微带贴片天线

为适应卫星移动通信中天线低剖面要求,设计了一种缝隙耦合馈电的双极化微带贴片天线。该天线为多贴片堆栈形式,双线极化通过H型缝隙进行耦合馈电,在贴片的上方辅以寄生贴片,以提高天线的增益和辐射效率。通过对影响天线性能的各个参数进行优化,垂直和水平极化双端口的驻波比在＜2时,分别覆盖22%和30.6%的带宽,端口隔离度＜30 dB,波束宽度均＞70°。该设计天线可作为固定波束或相控阵天线进行卫星通信。     

X波段圆极化透射阵天线

设计了一种具有极化转换功能的圆极化透射阵天线单元。该单元具有3层结构,包括线极化接收贴片、地板和圆极化辐射贴片,通过旋转圆极化辐射贴片来实现相位补偿。采用该单元设计了一种具有极化转换功能的圆极化透射阵天线,并对其进行了仿真。仿真结果表明,在10 GHz处天线的增益和口径效率达到最高,分别为24 dBi和31%,天线的3 dB增益带宽为9%(9.6~10.5 GHz)。与一般的透射阵天线相比,该透射阵的焦径比仅为0.33,具有剖面低的优点。对该天线进行了加工和测试,测试结果与仿真结果基本吻合。     

四点馈电的双极化单层微带背腔天线

设计了双线极化的3单元线阵天线及其馈线网络。利用四点馈电结构提高微带贴片单元的极化纯度,加载背腔提高其工作带宽,在贴片上引入环形槽缝进一步提高阻抗匹配,采用各馈点单独匹配技术消除小阵中无法忽略的边缘效应,并在馈电过渡结构上做了一系列加固设计。对两块实物的测试表明,该天线阻抗带宽超过21%,交叉极化低于-30d B,辐射效率不低于85%。本天线具有剖面低、抗振性强、架设简便等优点,具有很好的工程应用价值。     

双频双极化微带共形天线

设计了一款工作在不同频率的双极化微带共形天线。首先,天线单元采用矩形微带贴片,并且通过改变贴片尺寸实现两种谐振频率;其次,改变两种单元的馈电方向,以此实现不同极化辐射;最后根据天线单元排布形式,设计了基于T 型功分器的馈电网络。根据最终的仿真结果,加工了天线实验样机。在工作带宽内,天线1、2 不圆度为分别为3. 56dB 和3. 98dB,增益分别为1.1dBi 和0.85dBi。通过比对,实测结果与仿真结果一致性较好,达到了预期目标。     

机械结构对阵列天线交叉极化特性影响的研究

以全球微波接入互操作系统（WiMax）增补频段上的四单元宽带贴片天线阵列为研究对象,通过分析计算和实验测量,详细研究了机械支撑结构对宽带微带贴片天线阵列的交叉极化性能影响。分析及测试结果表明,介质支撑结构的阵列天线具有更好的交叉极化特性。文章的结论对改善贴片阵列天线的极化纯度、优化天线单元的机械支撑结构具有实际意义。     

基片集成波导双圆极化贴片天线的设计与实现

为了提高通信系统的通信容量,设计了一种基片集成波导(SIW)双圆极化贴片天线。该天线由耦合器、贴片天线构成。基于空腔模型研究,耦合器采用SIW结构,其输出端信号在较宽的带宽内具有良好的稳定性;在分析微带天线理论基础上,引入贴片天线作为辐射单元,结构简单,易于实现;在传输线模型理论中,天线输入端口采用共面波导(CPW)的转换结构是必不可少的,可以直接与SMA转接头相连,方便测试。该天线可以根据其应用需求调整工作极化方式,可以实现左旋圆极化(LHCP)和右旋圆极化(RHCP)。通过测试加工后的天线验证了仿真数据。结果表明,该天线相对带宽超过18%(19.5 GHz~23.5 GHz),在工作频率范围内,轴比参数小于2,可实现增益7.4 dB。     

Dual-polarized slot-coupled planar antenna with wide bandwidth

A new dual-polarized slot-coupled microstrip patch antenna is presented, which can achieve high-isolation, low cross-polarization levels, a wide bandwidth, and low backward radiation levels. The coupling slot is an H-shaped slot. For wide bandwidth and easy integration with active circuits, it uses slot-coupled stacked microstrip patches. The theoretical analysis is based on the finite-difference time-domain (FDTD) method. First, a parametric study on the input impedance of the antenna with a single input port is presented. Based on the results, a dual-polarized microstrip antenna is designed, fabricated, and then measured. The measured return loss exhibits an impedance bandwidth of over 20.9% and the isolation between two polarization ports is better than 36 dB over the bandwidth. The cross-polarization levels in both E and H planes are better than 22 dB. The front-to-back ratio of the antenna radiation pattern is better than 21 dB. Both theoretical and experimental results of return loss, isolation, and radiation patterns are presented and discussed.     

Corner-fed microstrip antenna element and arrays for dual-polarization operation

A systematic study on the dual-polarized corner-fed microstrip antenna element and arrays with thin single-layer structure is presented. The impedance matrices and S-parameters of the element and arrays are investigated by the proposed extended multiport network method (EMNM). The co- and cross-polarization patterns are also analyzed. It is shown that this kind of antenna element has an isolation about 10 dB higher than that of a conventional edge-fed square patch. A series of new dual-polarized arrays of corner-fed patches have been designed and analyzed based on the EMNM. The experimental results of five arrays indicate that these arrays achieve an isolation of 27/spl sim/38 dB with a maximum of higher than 28/spl sim/58 dB and cross-polarization level of lower than -23/spl sim/ -30 at boresight, which are substantially better than those of similar dual-polarized arrays of edge-fed patches. All theoretical results are in good agreement with experimental ones.     

High isolation dual-polarized patch antenna using integrated defected ground structure

This letter presents a high isolation dual-frequency orthogonally polarized rectangular patch antenna utilizing microstrip feed line integrated with a defected ground structure (DGS). The demonstrated approach results in a significant improvement in port isolation in comparison to a conventional dual-polarized antenna fed by simple microstrip lines. Measurements show an improvement of 20 dB in port isolation relative to the conventional antenna, operating at 2 and 2.5 GHz. Image impedance of a microstrip line with DGS is controlled by the DGS geometry without modifying the dimension of the line. A 150 /spl Omega/ high impedance line is effectively implemented using a microstrip line with 75 /spl Omega/ line width by incorporating the DGS.     

一种新型宽带双极化微带贴片天线的设计

摘要：运用口径耦合理论、腔模理论、反相馈电技术和多层贴片结构设计出一种新型的P波段（中心频率为0．75GHz）宽带双极化微带贴片天线。天线的两个极化端口采用共面馈电;馈电网络设计中采用短路耦合线实现反相馈电。仿真结果表明该天线两个极化端口实际增益均达到8．5dB,水平极化端口在0．64-0．85GHz频率范围内驻波比小于2,相对带宽为28％;垂直极化端口在0．68-0．85GHz频率范围内驻波比小于2,相对带宽为22．6％,两端口隔离度高于53dB。     

Wideband Dual-Polarized Patch Antenna With Broadband Baluns

A pair of novel 180deg broadband microstrip baluns are used to feed a dual-polarized patch antenna. The 180deg broadband balun delivers equal amplitude power division and consistent 180deg (plusmn5deg) phase shifting over a wide bandwidth (>50%). We demonstrate that for a dual-polarized quadruple L-probe square patch antenna, the use of the proposed 180deg broadband balun pair, in place of a conventional 180deg narrowband balun pair, provides improved input port isolation and reduced H-plane cross-polarization levels over a wider frequency range, while maintaining low E-plane cross-polarization levels and stable E- and H-plane co-polarization patterns throughout the impedance passband     

一种新型星载SAR宽带双极化微带天线研究

提出了一种新型宽带双极化微带天线：天线单元采用层叠结构,下层为正方形辐射贴片,上层为圆形寄生帖片。同时给出了常见的正方形寄生贴片的结构参数,计算结果表明：采用圆形寄生贴片的新型天线与一般的正方形寄生贴片天线相比,在带宽、隔离度和交叉极化电平等性能上均具有优势,尤其是交叉极化特性,优于正方形寄生贴片结构-5dB左右,具有重要的工程应用价值。     

Ku 波段口径耦合宽带双极化微带天线

本文综合运用双层贴片和口径耦合馈电拓展了微带天线的带宽,设计了一个工作在Ku 波段的宽频带双极化 微带天线。利用在架高层介质上开腔体的方法实现对于寄生贴片的架高,既能有效降低天线成本,又可实现较低的等 效介电常数。基于这种双极化单元组成了一个2×2 的微带天线阵列,仿真结果表明两端口分别拥有20.5%和20.1%的 阻抗带宽,两端口隔离度大于31dB,水平极化和垂直极化的极化隔离大于41dB 和46dB。     

一种Ka/Ku双波段双极化共口径阵列天线

由于运载能力及卫星平台的限制,星载雷达要求雷达天线具有重量轻、功耗低、体积小、效率高等特点,尤其是对天线口径面积限制较为苛刻,双频段天线要想适用于星载条件,就必须考虑全新的结构形式。介绍了一种适应于星载条件的Ka/Ku双波段双极化共口径阵列天线,其中Ku波段天线双极化工作、Ka波段天线单极化工作。Ku波段天线阵采用了具有两阶零点滤波性能的微带耦合馈电辐射缝隙单元,这种天线单元具有易实现双极化、工作频带宽等优点。Ka波段天线阵采用侧馈微带帖片天线单元,其优点是易于实现与Ku波段天线共孔径。     

新型光子带隙宽带双极化微带天线设计

设计了一种基于光子带隙（PBG）高阻表面的宽带双极化微带天线。将PBG高阻表面地板应用到设计的缝隙耦合微带天线上,实现了C波段阻抗带宽为22%（VSWR<2）的宽带双极化天线单元。仿真结果表明,与加金属地板的情况相比较,设计得到的PBG高阻表面在减缩剖面的同时,改善了天线的阻抗带宽、增益、端口隔离度和交叉极化,其中端口隔离度最大可以提高约8dB、轴向交叉极化可以提高约4dB。     

Broad-band dual-polarized single microstrip patch antenna with highisolation and low cross polarization

This paper presents a new design of a broad-band dual-polarized single microstrip patch antenna with highly decoupled input ports and low cross-polarization (XP) radiation. A prototype of the proposed antenna with center frequency at 1800 MHz is presented. Both the dual linear polarizations have 10-dB return-loss impedance bandwidths greater than 14% and high decoupling between the two input ports (S₂₁ less than -40 dB across the entire bandwidths) is obtained. Moreover, the XP radiation in the principal planes of the dual linear polarizations is seen to be less than -20 dB