一种H型缝隙和L型探针耦合双极化微带天线的设计

设计了一种宽带、低交叉极化、高隔离度的双极化微带天线结构,采用L型探针耦合和H型缝隙耦合两种方式相结合,结构简单.天线设计频率为2.4 GHz,两端口-10 dB阻抗带宽达到26.7%和30%,隔离度在整个带宽内低于-32 dB、交叉极化电平在60°方位角内低于-24 dB、在主瓣内低于-32 dB,理论仿真和实验测试结果吻合较好.     

Stacked H-shaped microstrip patch antenna

A small H-shaped microstrip patch antenna (MPA) with enhanced bandwidth is presented. The H-shaped antenna is first studied by a transmission line model and then is fully analyzed with a MoM code. A stacked patch configuration is proposed to increase the narrow bandwidth, radiation efficiency and directivity. The stacked H-shaped MPA is studied using Chu's fundamental limit for electrically small antennas.     

Analysis of an aperture coupled microstrip antenna

A microstrip patch antenna that is coupled to a microstripline by an aperture in the intervening ground plane is analyzed. Coupled integral equations are formulated by using the Green's functions for grounded dielectric slabs so that the analysis includes all coupling effects and the radiation and surface wave effects of both substrates. A Galerkin moment method solution of the coupled integral equations agrees quite well with measured data. Design data are contained in parameter studies, many of which are verified by experimental results.     

一种开双H形槽的新型宽频微带天线

提出了一种在接地板和辐射贴片同时开H形槽的新型宽频微带天线。设计了一个工作于Ku波段的微带天线。采用时域有限差分（FDTD）方法对该天线的电特性进行了仿真计算,并制作了实验模型。测量结果表明,该天线驻波（VSWR）小于2的相对阻抗带宽达到了37．6％,交叉极化电平小于-17dB。     

Network modeling of an aperture coupling between microstrip lineand patch antenna for active array applications

An analytical method based on the aperture coupling theory and the derivation of the S-parameter matrix has been developed for modeling a microstrip line coupled to a microstrip patch antenna using a circular coupling aperture. Closed-form solutions were derived for scattering parameters of the coupling circuit. Input impedance and matching condition can be calculated from the equivalent six-port network. The theoretical results agree well with the measurements. The analysis should have many applications in active array and spatial power combining systems     

Circularly polarised aperture coupled microstrip antenna

The orthogonal mode of an aperture coupled rectangular microstrip antenna can be coupled to the aperture-excited mode with coplanar microstrip lines to provide a compact circularly polarised element with a single aperture feed. An equivalent circuit model was developed for the analysis and design of this element, and a working version was used to demonstrate the concept. The features of this antenna are compared with several other circularly polarised microstrip antennas     

A new aperture coupled microstrip slot antenna

A new aperture coupled design is proposed for microstrip slot antennas to improve their radiation performance. The proposed design is based on a new aperture coupling technique in which the slot is fed by a microstrip line and coupled to several parasitic patch radiators etched on the opposite side from the slot. In contrast to the combination of a slot and a microstrip patch in conventional aperture coupled microstrip antennas, the patches here are employed to reduce the radiation into the half-space that they occupy and increase the radiation in the other half-space. Therefore, the slot antenna can produce radiation patterns with a high front-back ratio. The above objective is achieved by optimizing standing wave distributions of the aperture electric field in the slot through the adjustment of the position of the patches along the axis of the slot. In this paper, design considerations are given, and the results are validated by numerical simulations and experimental measurements.     

Improved coupling for aperture coupled microstrip antennas

Aperture shape and size are the crucial parameters for the aperture coupled microstrip antennas (ACMSA). A systematic comparision of various aperture shapes for the aperture coupled rectangular microstrip antenna has been carried out. An optimum “hour glass”-shaped aperture configuration has been proposed for maximum coupling     

Improved coupling for aperture coupled microstrip antennas

An aperture shape that gives significantly improved coupling for an aperture coupled microstrip antenna is described. This 'dogbone' aperture consists of the usual rectangular slot augmented with loading slots at each end. Measured data show an increase of more than three for the resonant input impedance of an antenna using the dogbone-shaped aperture, as compared with the input impedance of the same antenna with a rectangular slot of the same overall length. The field distributions of both slots are also measured, and compared.<>     

Dielectric resonator antenna using aperture coupling

A practical antenna configuration for use at microwave and millimetre wave frequencies is investigated. It consists of a circular cylindrical dielectric resonator fed by a microstrip feedline through a coupling aperture in the ground plane between them. Several elements, with different physical parameters, operating between 14 and 16 GHz were constructed and tested. Experimental results confirm the effective and practical performance of the antenna structure.<>     

Flat lens antenna concept using aperture coupled microstrip patches

A planar lens antenna based on aperture coupled microstrip patch elements with stripline delay lines is described. Features of this design are discussed, and results for transmission coefficient magnitude against frequency are presented. The background for the development of this lens configuration is discussed in terms of a natural progression from frequency selective surfaces, and the inadequacies of simpler geometries are explained     

Wideband and high-gain one-patch microstrip antenna coupled withH-shaped aperture

The design, fabrication, and experimental implementation of the one-patch microstrip antenna coupled with an H-shaped aperture are presented. The presented antenna has a wide bandwidth, high gain, and low cross-polarisation levels with only one-patch. The measured bandwidth of this antenna is 56.2% for the voltage standing wave ratio ⩽2.0. The cross-polarisation level is below -18.2 dB at the E-plane and below -25.7 dB at the H-plane. The maximum gain at 2.05 GHz is 10.4 dBi and the 3 dB gain bandwidth with a centre frequency at 2.17 GHz is 24%     

A couple microstrip antenna employing serrated coupling

Microstrip antenna is suitable for mobile handsets due to its light weight and compactness. The disadvantages of narrow bandwidth is necessary to be improved for modern wireless communication systems. This paper proposes the serration of coupled microstrip antenna to improve in the impedance characteristics. Return loss of this antenna is analyzed in terms of serration. The obvious measured characteristics improvement can be observed. They are found to be useful for practical wireless communication systems.     

高隔离度双极化孔径耦合天线设计

采用多层贴片、垂直双H型孔径耦合结构设计了一种高隔离度双极化孔径耦合微带天线。主要通过实测分析不同贴片间距以及孔径大小对天线隔离度的影响,确定了最佳贴片间距和孔径尺寸。经AgilentES062A矢量网络分析仪实测,得出天线两个端口的回波损耗在2．4～2．5GHz能达到一16dB以下,在工作频段内双端口隔离度优于一31dB,与仿真结果吻合较好。该设计结构简单,成本低廉,易于制作,且可作为双极化基站阵列天线单元。     

Circular-disk microstrip antenna with an air gap

The circular-disk microstrip antenna with an air gap between the substrate and the ground plane is analyzed using the cavity-model theory. A simple formula for the resonant frequencies is obtained. The internal fields, the radiation fields, the effective loss tangent, and the input impedance are derived when the antenna is provided with a coaxial feed. The theory predicts that the air gap does not alter the relative field patterns significantly but it provides a simple parameter by which the resonant frequencies of the antenna can be tuned. Measurements have been performed on a 5 cm circular-disk microstrip antenna with an air gap and good agreement between theory and experiment is obtained.     

Characterisation of aperture coupled microstrip patch antenna withthick ground plane

The feasibility of using a thick ground plane with an aperture coupled microstrip patch antenna while maintaining reasonable antenna performance is demonstrated using moment method and reciprocity analyses in the spectral domain. The thick ground plane, which may serve as a heatsink for active MMIC circuitry, or as a mechanical support for thin substrates, is particularly advantageous in millimetre wave phased array applications. It is found that the effect of ground plane thickness is to reduce the level of coupling from the feed line to the patch     

Wideband dielectric resonator antenna excited by cavity-backed circular aperture with microstrip tuning fork

A wideband dielectric resonator antenna excited by a circular aperture is investigated experimentally. The aperture is coupled by a microstrip feedline with a microstrip fork-like tuning stub. A backing cavity is placed beneath the stub to block undesirable backside radiation. The return loss, field pattern, and antenna gain of the proposed configuration were measured, and the results are compared with those without the backing cavity.     

An aperture coupled microstrip antenna with a proximity feed on a perpendicular substrate

A new feeding configuration for microstrip antennas is described, where separate substrates are used for the radiating patch element and the microstrip feedline. The substrates are joined perpendicular to each other, and the patch is excited through an aperture in the antenna substrate ground plane by proximity coupling to the microstrip feedline, This design thus has a number of advantages over other feeding configurations, particularly when used in an integrated phased array application. These features, as well as the measured results from two experimental models, are described.     

Design of aperture coupled microstrip antenna array fed bydielectric image line

A novel design for a linear array of microstrip antennas, aperture coupled to a dielectric image line has been developed. The design is based on a simplified theory to determine the impedances of the antennas at their apertures, and in turn, the coupling to each antenna from the image line. The theory developed is verified using an eight-element linear array and the experiment results are very good     

缝隙加载H形双频天线

为了适应现代双频通信系统的要求,双频天线必须具有小尺寸和频率易调节的特点.通过在H形微带天线的辐射边附近采用U形缝隙加载,在单层微带天线上实现了双频效果.和常规的双频微带贴片天线相比,该天线的尺寸可以大大减小.通过改变天线的尺寸参数,高频段和低频段可以很容易地调节,本设计中得到频率比范围是1.716～2.363.该天线在两个频段有相同的极化平面和较宽的辐射波束.