新型X波段波导缝隙阵列天线的设计

为了克服传统波导缝隙阵列天线重量大、副瓣偏高等问题,提出一种小型化、低副瓣X波段波导缝隙阵列天线的设计方法。首先采用高斯分布实现其幅度加权,快速完成低副瓣波导缝隙阵列天线的设计;然后结合HFSS 软件对传统压缩波导的窄边尺寸进行优化,减小窄边尺寸;同时采用3D 打印技术制造ABS 塑料波导缝隙框架和金属电镀工艺实现天线的加工,通过仿真分析和实物加工测试验证了所设计天线的有效性。所设计的天线方位面副瓣电平可达到-25 dB 以下,重量从25 kg 减小到2.5 kg,减重比达到了90%。最后,详细分析了不同金属电镀层厚度对天线性能的影响。     

一种宽带高增益太赫兹透镜天线及其组阵设计

给出了一种宽带高增益的太赫兹介质透镜天线的设计方法，该太赫兹透镜的中心工作频率为220 GHz,工作带宽超过20 GHz,透镜外形为边长118 mm的方形。太赫兹透镜采用平凸透镜形式，透镜材料选用低损耗的氧化铝陶瓷，介质透镜前后表面带有阻抗匹配层，起到减小空气-介质交界面电磁波反射的作用。综合采用上述3种设计手段的太赫兹透镜天线实现了高增益和高效率。在太赫兹透镜天线容差分析的基础上，加工了太赫兹馈源网络和透镜样机，并进行了实物测试。实测太赫兹馈源网络的驻波、极化隔离度、天线增益和天线方向图均与仿真较为接近。进一步，将该阵列单元用于组阵以继续提高太赫兹天线增益，给出了周期组阵和非周期组阵2种布阵设计。计算结果表明，通过非周期组阵设计的透镜阵列天线，可以将栅瓣电平由-8.38 dB抑制到-13.69 dB。     

太赫兹孔径编码成像分辨性能研究

太赫兹孔径编码成像综合了光学孔径编码成像和微波关联成像的基本原理,通过孔径编码天线改变目标区域太赫兹波空间幅相分布来实现高分辨、高帧率、前视凝视成像。基于孔径编码天线,该文设计了雷达成像系统和准光扫描光路,可同时实现系统孔径编码和波束扫描功能,理论推导并仿真分析了其成像质量影响因素,并在此基础上比较了不同算法对孔径编码成像分辨性能的影响,证明了稀疏重构类算法对孔径编码成像的优势,最后对比了孔径编码成像和同尺寸阵列实孔径成像的结果,论证出孔径编码成像系统具有高分辨,易于小型化,成本较低等优点。该成像方式可广泛应用于战场侦查、安检反恐和末制导等领域。      

具备阻抗和低副瓣宽带特性的脊波导缝隙阵列天线设计

设计了一种16×8脊波导缝隙阵列天线,线阵阵面分成两个子阵,馈电采用同轴馈电与耦合缝隙馈电结合的两级馈电方式,辐射缝隙分布为泰勒分布。天线设计采用近场诊断方法和阻抗过载技术进行优化。天线实物加工测试结果表明,天线在X频段驻波带宽(VSWR≤1.5)为7.3%,最低副瓣达到-25.8 dB,副瓣电平带宽(SLL≤-19 dB)为6.2%。与已有文献相比,该天线同时具备阻抗宽带特性和低副瓣宽带特性,工作频带内具有增益均大于16 dBi的高增益特性。     

一种波导窄边裂缝天线缝隙倾角的改进方法

为减小波导窄边裂缝天线缝隙间互耦对天线性能的影响, 实现低副瓣的设计, 提出了一种倾角波动分布的设计方法.天线电流分布选用泰勒分布, 利用HFSS软件确定缝隙倾角初值, 在此基础上得到波动分布的倾斜角度, 并通过遗传算法对缝隙倾角进行优化.使用Matlab与HFSS软件联合仿真, 省略了建模、设置参数等大量操作, 提高了设计效率.基于此, 设计了一款长度为1.2 m的X波段波导窄边裂缝天线, 仿真发现副瓣电平比传统设计方法低2.17 dB, 加工了天线实物并进行了测试, 天线实测增益和副瓣电平分别为20.9 dBi和-28.7 dB, 验证了方法的有效性.     

基于电调超表面及柱面反射面的相控阵天线设计

提出了一种基于电调可重构超表面的低成本相控阵天线。该天线结构由天线底部的抛物线反射面馈电网络、上层的波导缝隙阵列及在波导中加载的电调超表面3部分组成,通过抛物线反射面将馈源在天线下层平板波导中产生的柱面波转换为平面波并用来激励天线上层的波导缝隙阵列。为了实现低成本的波束扫描,在每条独立的波导缝隙天线前端加载了具有360°相位调制能力的电调超表面。通过改变变容二极管上的偏置电压的大小可改变超表面的透射相位,实现连续的波束扫描能力。该天线可实现±30°的连续波束扫描,最大副瓣电平值为-13 dB,增益变化为-2 dB。该天线的低成本、高效率的波束扫描特性使其非常适合应用在一些低成本的雷达及通信系统中。     

K波段低副瓣波导缝隙驻波阵设计

本文设计了一种 K 频段低副瓣波导缝隙驻波阵天线,给出了实现低副瓣的方法。设计副瓣电平为-27dB,缝隙幅度分布按-30dB 泰勒分布计算,结合高频仿真软件 Ansoft HFSS 对各缝隙归一化导纳进行计算,建立仿真模型并优化天线各参数。依据设计结果加工实物并测试其方向图及增益。测试结果表明,该天线在工作频带内波束宽度约 3°,副瓣电平小于-27dB,工作频带内增益大于 30.8dB,仿真结果与实测结果相符,设计满足指标要求。     

用于单脉冲的脊波导缝隙相频扫天线设计

对于单人便携式单脉冲雷达,设计高增益、宽扫描角度、低副瓣电平和低剖面的天线阵列对提高其探测距离、探测范围和探测精度有着非常重要的意义.设计了一种S型脊波导缝隙相频扫天线,采用S型脊波导来缩减波导的宽边尺寸,增加频率扫描波束范围.将频率扫描线阵分为两个子阵,采用同侧馈电,分别进行Taylor幅度加权,在保证分段处幅度和相...     

波导窄边缝隙阵列天线的分析与设计

波导窄边缝隙阵列天线由于效率高、功率容量大、稳定性好及副瓣电平低等特性,在雷达体制上使用广泛。对于单一波导窄边缝的隙线阵,根据设计指标,首先分析其理论模型并给定理想的设计参数,再利用Ansoft公司的HFSS软件的参数扫描及优化功能,通过局部调整设计参数就可以方便地得到缝隙的谐振结构。利用这种设计方法可以快速得出所需要的低副瓣窄边波导缝隙阵列天线。     

脊波导缝隙圆极化天线的设计*

设计了一种新型脊波导缝隙圆极化天线。在脊波导宽边开并联纵缝,从波导耦合电磁波至其上方的四脊波导圆极化器,实现圆极化辐射。采用脊波导不仅减小了单元尺寸,更改善了天线的带宽性能。重点研究了四脊波导圆极化器对相互垂直的两辐射场分量的影响,优化单元的轴比特性。在提取单元谐振电导的基础上,设计了工作在10GHz 的1×10 圆极化波导缝隙阵列。对天线实物测试得到中心频率处的增益为16.8dB,第一副瓣电平为 25dB,阻抗带宽约为8.5%,相对轴比带宽(AR臆3dB)约为3.2%。     

Phase-only control of antenna sum and shaped patterns through nullperturbation

Satisfactory sum or shaped antenna radiation patterns can often be synthesized by modifying just the phase distribution of an initial excitation by an arbitrary amplitude distribution. As examples, we calculate linear and circular apertures with uniform, Taylor, or cosine-section amplitude distributions, affording symmetric sum patterns with low sidelobe levels or symmetric shaped patterns with low ripple and sidelobe levels; linear aperture distributions, affording patterns with low sidelobe levels on one side of the beam; and planar arrays, with uniform or cosine-section amplitude distributions affording φ-symmetric or elongated-oval footprints     

Study of Low Sidelobe Time Modulated Linear Antenna Arrays at Millimeter-Waves

In this paper, the time modulation technique for the design of low sidelobe antenna arrays is extended to millimeter-wave frequency band. Millimeter-wave rectangular waveguide is selected as the element radiators of linear antenna arrays, and the element radiation patterns are taken into account in the analysis and design of low sidelobe time modulated linear arrays. Two types of time modulation, namely, the time modulated variable aperture sizes (VAS) and unidirectional phase center motion (UPCM), are implemented in the design of low sidelobe millimeter waveguide linear arrays. It is observed that both the co-polarized and the cross-polarized components will experience the time modulation effect simultaneously. Many factors that affect the array performance are discussed.     

太赫兹光子晶体光纤与天线设计

以聚甲基丙烯酸甲酯(PMMA)材料为基质,设计了一种空芯多孔包层结构的太赫兹光纤,中心的大孔缺陷用于传输太赫兹波,周围四层小孔可以将太赫兹波的传播限制在缺陷内部。利用COMSOL软件对光纤的损耗特性进行仿真分析发现,光纤在0.6 THz的泄露损耗低于0.1 dB/m,具有良好的传输特性。和金属波导口可以当作天线辐射电磁波的原理相似,光纤的端面也可以作为天线将内部传输的太赫兹波向外辐射,通过仿真分析,天线在0.59~0.61 THz的回波损耗低于-25 dB,方向性系数大于20 dB,半功率波束宽度约为13。     

A frequency-controlled beam-steering array with mixing frequency compensation for multichannel applications

A frequency-controlled beam-steering planar array with mixing frequency compensation is presented for cost-effective multichannel phased array applications. The new feed networks for frequency compensation not only operate in wide band but also ensure radio-frequency (RF) amplitude imbalance cancellation and progressive phase distribution. The parallel equal power dividers installed in both LO and intermediate-frequency (IF) feed networks provide uniform amplitude and phase distribution, while the fixed delay lines installed in the LO feed network exhibit precise phase progression, compared to a series feed structure. The LO power imbalance caused by the unequal delay line loss between elements is corrected by pumping each mixer into the LO saturation region, leading to linear IF-RF response. Thus, sidelobe degradation and pattern distortion caused by the RF amplitude imbalance, as well as the beam-steering error and beam squint caused by the phase errors of the delay lines, are removed. The proposed feed networks combined with quasi-Yagi antenna arrays and microwave monolithic integrated circuit mixers realize a broad bandwidth of more than 3 GHz in K band for multichannel wireless applications. The K band transmitter/receiver pair proposed in this paper successfully demonstrates two-channel simultaneous RF transmission and single channel 50-Mb/s data communication with 40/spl deg/ scanning. This simple, compact, yet cost-effective planar array ensures multichannel broadband wireless communications with beam-steering capability.     

一维液晶全息编码相控阵天线设计与实现

针对小型极化相控阵雷达精确信号目标探测应用背景,为降低传统T/R相控阵天馈系统设计及调试复杂度,满足低功耗、低损耗、低成本制造、轻薄等应用需求,提出了一种液晶全息编码相控阵天线.主体采用小型化全息辐射单元、慢波结构、平行板波导馈电系统构成的一维全息电控扫描相控阵天线,利用成熟液晶面板制造工艺,通过控制全息辐射单元下方液晶分子的偏转状态调节天线谐振频点,组成全息编码相控阵天线.天线结构通过仿真优化确定,并在实物加工和测量基础上通过全息优化算法及电压灰度控制降低由耦合作用引入的副瓣性能恶化度,用梯度递减的搜索算法结合适当的目标函数优化算法实现方向图的最优控制.实测结果表明,该天线的波束扫描角度达到±49°,经过算法优化后,波束指向角准确度改善3°,旁瓣抑制电平改善1.7 dB.     

Design and analysis of a reconfigurable dual-beam grating antenna for low-cost millimeter-wave beam-steering

This paper presents a reconfigurable dual-beam grating antenna for low-cost millimeter-wave beam steering. Experimental results indicate that this multibeam approach provides over /spl plusmn/50/spl deg/ beam steering at fixed frequencies across the entire 35 to 40 GHz band, with excellent radiation patterns maintained across the scans. An approximate analysis developed for the reconfigurable antenna closely predicts the observed scan angles and main beam radiation patterns across the complete range of scan states. These results should have numerous applications in millimeter-wave beam-steering technology.     

光生等离子体栅扫描天线研究进展

毫米波和太赫兹(THz)波天线扫描技术已经成为当前电磁领域研究的热点,光生等离子体栅(PIPG)扫描天线技术作为一种低成本的快速扫描技术为操控毫米波和THz波提供了新的方法和思路。本文将对PIPG扫描天线的原理、结构、效率和方向图等主要研究进展做详细的论述,并且对PIPG扫描天线的研究意义和存在的主要问题进行讨论和展望,希望对PIPG扫描天线的研究和应用提供参考。     

18–40-GHz Beam-Shaping/Steering Phased Antenna Array System Using Fermi Antenna

This paper concerns 18-40 GHz 1times 16 beam shaping and 1times 8 beam steering phased antenna arrays (PAAs) realized on a single low-cost printed circuit board substrate. The system consists of a wideband power divider with amplitude taper for sidelobe suppression, wideband microstrip-to-slotline transition, a low-cost true time piezoelectric transducer (PET)-controlled phase shifter, and wideband Fermi antennas with corrugations along the sides. A coplanar stripline is used under a PET-controlled phase shifter, which can generate 50% more phase shift compared to the perturbation on microstrip lines previously published. The systems are fabricated using electro-fine-forming microfabrication technology. Measured return loss is better than 10 dB from 18 to 40 GHz for both the beam-shaping and beam-steering PAAs. The beam-shaping PAA has a 12deg 3-dB beamwidth broadening range. The sidelobe ratios (SLRs) are 27, 23, and 20 dB at 20, 30, and 40 GHz, respectively, without perturbation. The SLRs are 20, 16, and 15 dB at 20, 30, and 40 GHz with maximum perturbation. The beam-steering PAA has a 36deg (-17deg to +19deg ) beam-scanning range measured at 30 GHz.