用于空间功率合成的线阵馈电焦散抛物曲面天线

提出了一种用于空间功率合成的焦散抛物曲面天线,该反射面天线是由xoz平面的一条抛物线沿着yoz平面上的另一条抛物线正交扫描所形成的,天线用8单元E面喇叭线阵进行偏馈。研究了天线的反射面结构参数对天线性能的影响以及横向偏焦电扫描特性,给出了不同辐射方向下阵列的相位配置公式。仿真和实验结果表明:提出的方案可以在给定方向合成高增益波束,与同样线阵馈电的抛物柱面天线相比,H面3dB波束宽度从8.2°下降到了5°,天线增益提高了2.2dB.     

一种Ku波段宽带T型相控阵天线的设计

为同时兼顾天线的电性能和成本，设计了一种 Ku 波段的宽带 T 型雷达相控阵天线， 给出了天线的分析和设计过程。天线由两个一维线阵组合而成，正交布置的两个一维线阵可在小角度范围内形成正交的双扇形波束，实现有限相扫。在满足了雷达天线扫描精度需求的同时，减少了天线单元和移相器数量，降低了天线成本。经实际测试，在 34 %的工作带宽内，单个线阵增益大于30.9 dBi。相干合成工作模式下，天线增益较单线阵增益增加约3 dB，波束宽度为1°×1°， 测试结果与设计分析具有良好的一致性。     

一款具有稳定扫描波束分辨率的宽视角相控阵天线北大核心CSCD

基于自适应稀疏阵的结构,提出了一种具有宽视角与稳定扫描波束分辨率性能的相控阵天线。阵列单元是可以在相同谐振频率下实现TM;和TM;两种模式共同工作的单激励圆环贴片天线,其具有140°的半功率波束宽度,这种宽波束辐射效果能够较好地拓展相控阵天线的扫描范围。基于此单元构建了一个35元线阵,对其波束扫描分析发现在限定增益波动小于2 dB的条件下阵列扫描范围可以达到-70°~+70°,但主瓣波束宽度随着扫描角度的增加而增大。为解决这个问题,引入了自适应稀疏阵的概念,并采用基于互耦补偿矩阵的迭代快速傅里叶变换(Iterative Fast Fourier Transform,IFFT)技术进行自适应稀疏阵的优化设计。结果表明,所提出的基于自适应稀疏阵结构的35单元相控阵天线在-60°~+60°扫描范围内增益波动始终小于1.5 dB,波束宽度波动小于1°,且峰值旁瓣电平基本保持在-20 dB以下。相较于均匀周期阵列,所提出的自适应稀疏相控阵天线能够在实现低旁瓣宽视角扫描的同时,有效提高天线在宽角度范围内扫描波束分辨率的稳定性。     

双层宽波束天线设计

针对宽波束天线在车载雷达中的应用,突破角雷达方位面3 dB波束宽度的限制,实现微带阵列天线在水平面的宽波束覆盖,设计了一款1×10串馈微带双层结构天线。线阵单元采用道尔夫-切比雪夫（Dolf-Chebyshev）综合法电流分布来达到降低天线俯仰面副瓣的效果,在串馈阵列上方加载寄生贴片和介质基板拓展天线方位面的3 dB波束宽度。分析了双层天线展宽波束的原理,加工并实测了双层宽波束天线,其方位面的3 dB波束宽度为134.6°,增益达到10.6 dB,副瓣电平为-19.8 dB,可以满足车载角雷达天线需求。     

H 形缝隙耦合双极化微带天线阵设计分析

设计并仿真了一种基于H 形缝隙耦合馈电,工作在u K 波段的微带双极化天线,并进行了4 单元平面组阵。4 单元阵实现的指标：驻波小于2 的相对带宽达到8.2%,双极化端口隔离度达-32dB,交叉极化达-23.5dB,方向图前后比 达-28dB,增益达到15dB,3dB 增益带宽达23.2%,并且两种极化下天线方向图有较好的一致性。天线采用多层结构,减 小了天线尺寸,并且两组馈电在不同夹层的设计使得进一步组阵变得便利,适应了双极化合成孔径雷达及抗多径干扰高 的移动通信系统的需要。     

一种宽频高增益的印刷偶极天线

设计了一种具有高增益、H 面宽波束的宽带印刷偶极天线。采用两元天线在E 面组阵,通过E 面波束宽度的压缩以获得较高的增益,同时保持了H 面的宽波束特性;采用微带线馈电,以在较宽的频带内实现阻抗匹配,并且微带线馈电易于设计组阵时的合路网络,且便于结构加工。经过仿真优化,本文天线实现了0.85GHz~1.9GHz 频带范围约75.6%的相对带宽内驻波比小于2;在0.95GHz~1.65GHz 带宽约58.3%的相对带宽内增益大于9dBi。     

C波段有源接收天线子阵的设计

随着无线技术的迅速发展,人们对无线设备的小型化要求日益提高,因此天线的小型化、宽带化和高增益成为了无线通信中的研究重点。有源天线由于其体积小、频带宽,受到广泛关注。针对这些发展要求,参考有源天线的2种形式,提出将二单元天线作为一个天线阵列的子阵,通过背馈方式与低噪声放大器集成形成一个有源接收天线子阵。测试结果表明,该有源子阵谐振频率在4.8 GHz,工作频段为4.6~5.0 GHz,在中心频率处回波损耗大于20 dB,增益大于15 dB,3 dB波束宽度为35.8°。与无源天线相比,同等尺寸下工作频带展宽得到拓展,增益得到明显提高。     

LTE专网1.4G及1.8G高增益天线的仿真与设计

本文设计了两款LTE专网1.4G及1.8G高增益天线。仿真结果表明：前向天线的设计在保证E面110度H面71度半功率波束宽度的情况下,在1.4G和1.8G上的增益可达7.8dB,定向天线在E面100/120度H面可达40度半功率波束宽度的情况下,在1.4G和1.8G上的增益可达10dB/9.8dB。该天线的设计可用于对增益要求较高的1447-1467MHz频段和1785-1805MHz频段的LTE专网系统。     

一种串馈的非规则天线阵

均匀规则阵列天线的副瓣电平较差,且波束宽度较宽,不太适合于一维高精度相控阵雷达系统.针对这些要求,提出了一种基于串联馈电网络结构的非规则天线阵列.该阵列采用串馈方式,结合带空腔的微波多层板技术,通过带状线缝隙耦合方式,避免了背向辐射,同时获得宽带特性.该阵列采用遗传算法对阵列进行优化,获得低于-18 dB的理论副瓣电平,同时相比均匀规则阵而言,波束宽度仅有0.2°的拓宽.对于20°的波束宽度而言,该波束宽度扩宽量可以忽略不计.该阵列的实测2:1驻波带宽为19.8%,方向图带宽为12.2%,在方向图带宽内,阵列的实测副瓣电平低于-16 dB,阵列的带内测试增益高于11.7 dBi,实测结果和理论设计相吻合,表明该天线阵列适用于一维相控阵天线.     

双频水平极化全向天线设计

分析并设计了一种双频水平极化全向天线,该天线采用印刷偶极子组阵形式实现全向辐射性能,采用双辐射臂形式以及梯形渐变线馈电,实现在2.4~2.5 GHz和5.1~5.9 GHz上回波损耗低于-10 dB的双频特性。低频增益1.2 dB,不圆度为0.2 dB;高频增益2.4 dB,不圆度为2 dB。该天线结构简单,拥有良好的全向性。     

Asymmetric ridge waveguide radiating element for a scanned planararray

A novel linear array radiating element for use in a large low-sidelobe, planar slot array electronically scanned in azimuth is described. The planar array consists of many vertical resonant linear array elements; i.e. single ridge waveguides with broadwall shunt slots, closely spaced to avoid array grating lobes when the array is scanned in azimuth. Traditional linear broadwall slot arrays require alternating slot displacement from the waveguide centerline, which generates undesirable secondary beams in skewed directions during electronic scan. To eliminate the secondary beams, a design has been devised in which all slots are exactly collinear and lie on the waveguide centerline. The methods considered to achieve the required waveguide asymmetry, the design procedure used in the successful approach, and the experimental results obtained with a demonstration model are presented     

耦合纵缝馈电的短路波导宽边纵缝阵的分析与设计

基于三层结构（馈电缝、耦合缝、辐射缝）平面缝隙阵天线设计的需要,用场分析法对由耦合纵缝馈电的两端短路波导宽边直线纵缝阵进行了分析和综合。该法考虑了所有的互耦、高次模及波导壁厚的影响,得到了耦合纵缝馈电的两端短路波民宽边纵缝直线阵在辐射缝偏心距相同和缝长相同时直线缝阵口径分布等幅同相的结论。利用所得结论并结合泰勒线阵综合法提出了适合于对文中系统进行综合的有效方法。     

Theoretical and experimental studies of cavity-backed slot antennaexcited by a narrow strip

Theoretical and experimental studies of a cavity-backed slot antenna excited internally by a suspended narrow strip are undertaken. Coupled integral equations are developed to compute the electric field distribution in the slot and the surface current distribution on the strip. The input impedance of the cavity at the feeding point on the strip has been computed theoretically and measured experimentally. The impedance data, being a function of cavity dimension, slot length, strip length, and frequency, can be polyfitted and used to implement a systematic design procedure to construct a planar array of these slots     

Double-beam parallel-plate slot antenna

This paper presents the design and prototyping of a double-beam linear polarized parallel-plate slot antenna at 12-GHz band. Each beam is separated 27.7/spl deg/ and 27.3/spl deg/, respectively, from broadside direction. Two different radiation patterns are generated, exciting the parallel plate from opposite sides. The radiating elements are composed by three parallel slots, the central slot is close to the resonance, while the side ones are designed to minimize the reflection inside the parallel plate. The length of the slots in the same row is kept constant (periodic walls), and the distance between columns is equal to 0.7 times the wavelength. The designs of the feeding networks and the design of the array of slots generate both beams, pointing toward Hispasat and Astra satellites simultaneously, at the same frequency band. The feeding networks are two microstrip circuits that excite two linear arrays of 24 patches, placed at both sides of the antenna, and generate both quasi-TEM mode plane waves inside the parallel-plate waveguide, propagating from one side to the other.     

Low-cost printed collinear array antenna

This paper presents the design and antenna-prototype measurements of a low-cost antenna for DECT and LMDS system base stations (3400 to 3600 MHz). The specified pattern must be omnidirectional in the horizontal plane, having a maximum at the horizon. To produce this pattern, a linear array of printed patches, placed on both sides of a planar feeding structure, is designed The feeding structure is a symmetrical stripline, made with low-cost materials and designed to simplify the implementation tasks as much as possible     

Slotted waveguide linear array with polarisation control

The design of an experimental dual-mode waveguide linear array antenna is described and measurements on a 10-element model are presented. The antenna comprises a `notched? wall dual-mode waveguide containing an array of suitably located transverse/longitudinal slot pairs. Polarisation control is achieved by feeding the array through a 3 dB hybrid followed by a phase shifter.     

Grating Lobe Suppression of Narrow-Wall Slotted Hollow Waveguide Millimeter-Wave Planar Antenna for Arbitrarily Linear Polarization

A high-gain and high-efficiency slotted waveguide planar antenna is developed in the millimeter-wave band. Forty-five degree inclined polarization is required for automotive radar systems. In the design of slotted waveguide array for arbitrarily linear polarization, slot spacing is one guide wavelength which is larger than a wavelength in free space. Consequently, grating lobes appear in the radiation pattern. So, we developed a slotted waveguide planar antenna composed of post-loaded narrow-wall slots and a single-layer alternating-phase feeding circuit. A planar antenna with suppressed grating lobes has been fabricated and its RF performance has been measured. The measured gain is 33.2 dBi and antenna efficiency is 56% at 76 GHz. Grating lobe level is -28.6 dB lower than main lobe level. Since the proposed structure remains simple, the antenna is expected to be manufactured by metal injection molding for low cost     

表面波放电狭缝天线辐射电磁场的三维数值分析

针对平板型表面波放电等离子体源,建立了表面波放电狭缝天线辐射电磁波模型,对狭缝天线辐射电磁场分布进行了三维数值计算,并与表面波电磁场进行对比分析,讨论了平板型表面波放电机理。结果表明:整个狭缝天线阵激发的电磁场是每个狭缝天线激发电磁场的线性叠加;狭缝天线阵直接激发的电磁场强度在临近波导壁面处很大,并且随着空间距离的增大迅速衰减;狭缝天线阵直接激发和表面波的电场均远大于各自的磁场,分析电、磁场对带电粒子的力作用时可以忽略磁场力的作用;表面波电磁场远大于狭缝天线阵直接辐射的电磁场,强电磁场范围也远大于狭缝天线阵直接激发的强电磁场范围,等离子体有增强电磁场强度、扩大强电磁场范围的作用。     

Slots in Dielectric Image Line As Mode Launchers and Circuit Elements

Slots in the ground plane of dielectric image lines are investigated using a planar resonator model. An equivalent circuit representation of the slot discontinuity is derived and the launching efficiency of the slot as a mode launcher is discussed. Slots are also demonstrated to be useful in the realization of dielectric image line array antennas.     

线元天线阵列波束扫描研究

由电磁场理论给出了平面线元天线阵列辐射的瞬态电磁脉冲沿径向坡印亭矢量时间积分的解析解及数值解结果,并利用物理光学理论对所得结果作了对比分析,得到结论:(1)线元天线阵列辐射问题可以简洁地由光栅方程求解;(2)被约束波束的坡印亭矢量时间积分的最大值与阵元数目的平方成正比;(3)保持同一列辐射器元馈电同步,而沿行方向依次作适当馈电时间延迟,可有效将波束控制在预期的很小角域内;(4)保持扫描的半角宽度,线元天线阵列有确定的波束扫描角范围。