A reciprocity method of analysis for printed slot and slot-coupled microstrip antennas

A method is presented for the analysis of slot-type discontinuities in microstripline. The approach is based on the reciprocity theorem and uses the exact Green's functions for the grounded dielectric slab in a moment method solution for the unknown antenna currents. The method is applied to two specific geometries: a radiating slot in the ground plane of a microstripline, and an aperture coupled microstrip patch antenna. Results for antenna impedance are compared with measurements, and far-zone patterns are calculated. The method is shown to be quite versatile, and should find application to related problems.     

Analysis of cross-slot-coupled circular microstrip antenna

The analysis of a cross-slot-coupled circular microstrip antenna is presented. The approach is based on the reciprocity theorem and the exact Green's functions for the antenna structure. The equivalent circuit of the antenna was obtained. The calculated results for antenna input impedance were compared with the measured data.     

Calculation of radiation patterns of microstrip antennas oncylindrical bodies of arbitrary cross section

A simplified approach based on reciprocity is presented to calculate the radiation patterns of microstrip patch antennas or arrays on a cylindrical body having an arbitrary cross section. In this approach, the microstrip patch antennas are characterized using the finite-element method, and their radiation patterns are then calculated using a two-dimensional method of moments in conjunction with the reciprocity theorem. The validity of the calculation is demonstrated by comparison with measured data for a microstrip patch antenna on a circular cylinder attached to a plate. Other numerical examples are also presented to show the capability of the method as well as various effects of the host cylinder on radiation patterns     

背射模螺旋天线方向性研究及其应用

本文叙述了背射模螺旋天线的频率响应理论。基于电流行波的假设,求解了远区场的近似解析解。结果与Nakano的数值解基本一致,笔者应用该理论研究了以背射模螺旋作为馈源,导体圆板作反射器的新型天线的辐射特性。取得了具有实用意义的结果。     

Full-wave solution for an aperture-coupled patch fed byperpendicular coplanar strips

In recent years, the rectangular slot has been proposed as a means of power transfer between layers in multilayer printed antennas. Compared to probes, slots reduce fabrication complexity considerably, and allow more flexibility in the design of multilayer configurations. In the past, the aperture-coupled microstrip patch has been analyzed using the reciprocity theorem for the feeding line and the method of moments for the patch. The same method is used here for the analysis of an aperture-coupled patch fed by perpendicular coplanar strips. Theoretical results from this solution are compared with measurements for the input impedance of this antenna, and design data are given for the characteristic impedance of the coplanar strip feed line     

基于CC2430芯片的2.4GHz微带天线设计

针对无线模块中直立式天线体积大、功耗高问题,提出用微带天线替代传统直立式天线的方法,并讨论了微带天线的工作原理。介绍了中心频率为2.4 GHz微带天线的设计流程。根据需求确定微带天线的材料、形状、类型,用公式和软件计算出天线的尺寸等参数,再在Agilent公司的微波电路仿真软件ADS中建立天线模型并对其仿真,通过优化匹...     

A reflection array of loaded microstrip radiators

A planar reflection array consisting of a primary radiator and an array of secondary microstrip radiators such that the phases of the fields generated by these radiators are identical in the direction of radiation is considered. This identity is attained by means of a forced phase step of the reradiated field. An approximate method for calculating the phase step of the reflected field relative to the phase of the incident field that arises during reradiation of the incident signal by an element of the reflection array is proposed. The method is based on the theory of dipoles and the reciprocity theorem. Dependences of the phase step on the dimensions of the antenna and the reactive stub, as well as the capacitance of the capacitor formed by the slot cut in the antenna, are studied. The calculation method is extended to the case of a two-stack microstrip antenna. A method is proposed for setting the maximum of the radiation pattern of this reflection array in a specified direction via the use of an electric signal to control the capacitances of the capacitors in the array elements.     

Analysis of a dual circularly polarized microstrip antenna fed bycrossed slots

A dual circularly polarized, wideband microstrip antenna fed by two perpendicular crossed slots is analyzed in this work. The cross shaped aperture in the ground plane provides coupling between the microstrip patch and a single microstrip line underneath the ground plane, traversing the four arms of the cross in a serial manner, thereby generating four coupling points in phase quadratures for both senses of circular polarization. The analysis of this antenna incorporates two stages: In the first one, the individual load impedances are computed via an integral equation based on reciprocity, assuming no interactions between the ports. The second stage employs a transmission line model where the four coupling points are considered as lumped loads along the feed line. An iterative scheme employs the transmission line model for the determination of the actual impedances of each coupling point, including the mutual interactions with the other coupling points. This procedure provides control over the overall level of radiated energy; hence it can be used in the design procedure of this antenna as a serial or parallel fed array element. The computed results agree very well with measurements. The antenna attains a -3 dB gain bandwidth of 13% to 15%, a 3-dB axial ratio bandwidth of 48%, and -15 dB return loss bandwidth of 60%     

RFID基站天线与系统应用

针对RFID系统的应用特点,不同的应用领域所采用的天线也不同,应根据不同的读写范围、工作距离和天线的安装使用要求,来设计不同的基站天线方式。设计了工作在915MHz频段八木天线、螺旋天线、微带阵天线,并给出了仿真与测试结果。     

Analysis of two aperture-coupled cavity-backed antennas

The feasibility and performance of an aperture-coupled cavity-fed microstrip patch antenna and an aperture-coupled cavity antenna are demonstrated using reciprocity and moment method analyses, followed by practical design guidelines and equivalent circuit models. Each antenna incorporates a thick ground plane that can be useful as a heat sink for active MMIC circuitry and as structural support for thin substrates. Prototype antennas show good experimental agreement with the analyses in each case. The resonators of the aperture-coupled cavity-fed patch antenna are optimized to achieve a prototype having a measured 2:1 bandwidth of 26%. The size of the aperture-coupled cavity antenna can be easily reduced for array applications by filling the cavity with a dielectric material     

Microstrip antennas

Microstrip antennas have been one of the most innovative topics in antenna theory and design in recent years, and are increasingly finding application in a wide range of modern microwave systems. This paper begins with a brief overview of the basic characteristics of microstrip antennas, and then concentrates on the most significant developments in microstrip antenna technology that have been made in the last several years. Emphasis is on new antenna configurations for improved electrical performance and manufacturability and on advances in the analytical modeling of microstrip antennas and arrays     

Analysis of an arbitrarily inclined slot on the ground plane of amicrostrip line

The analysis of an arbitrarily inclined slot on the ground plane of a microstrip line is presented using the spectral domain approach and reciprocity theorem. Comparison of numerical results for the special case of a perpendicular slot with other available computed and measured data shows a good agreement. It is found that the impedance level can be controlled over a wide range by varying inclination angle. Results should be useful in antenna and multilayer circuit integration applications     

基于AMC的吸波材料及其在微带天线中的应用

研究了基于AMC结构的吸波材料在微带天线RCS减缩中的应用。给出了基于AMC结构吸波材料的表面阻抗的计算公式,并实际加工了吸波材料样品,分析了反射相位与表面反射系数之间的关系。将这种超薄AMC吸波材料应用于微带天线,实验结果表明:微带天线RCS得到有效降低,同时天线辐射性能得到保持,仅前向增益下降了0.9 dB。     

基于Polys try介质基板微带天线的应用研究

针对传统贴片天线检测频率有限(2~35 GHz)且由于增益低导致检测结果不明显的问题,文中提出了以聚苯乙烯作为介质基板构建微带天线的解决方案。在以介电材料玻璃超细纤维为介质基板的理论基础上,采用高分子材料Polysty作为介质基板构建微带天线模型。结合经典天线理论计算辐射贴片以及介质基板尺寸;基于HFSS搭建Polysty作为介质基板的模型并根据微带天线特性将理论设计的微带天线参数进行优化,最终得到在1 GHz时微带天线的最佳尺寸。仿真及实验结果表明,Polysty作为介质基板的微带天线中心频率可以达到1 GHz,增益高并且检测角度范围大。     

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     

Circuit model of microstrip patch antenna on ceramic land grid array package for antenna-chip codesign of highly integrated RF transceivers

This paper presents the circuit model of a microstrip patch antenna on a ceramic land grid array (CLGA) package for the antenna-chip codesign of a highly integrated radio-frequency (RF) transceiver. The microstrip patch antenna is fed by packaging interconnect components such as bond wires, signal traces, and vias in a ground-signal-ground (G-S-G) configuration from the carried chip. The circuit model that consists of RLC lumped elements of both microstrip patch antenna and feeding interconnect components has been developed with an emphasis on verifying existing or deriving analytical formulas. The RLC values of the microstrip patch antenna are calculated with our improvements to existing computer-aided design formulas, while the RLC values of the feeding interconnect components are calculated with more efforts. In particular the C values related to the vias and signal traces require to be calculated numerically and they are calculated here with the method of moments and the conformal mapping method, respectively. The circuit model is validated with numerical simulations (High Frequency Structure Simulator) and network analyzer measurements.     

新型微带缝隙天线的阻抗特性研究

在互易原理的基础上,用矩量法在谱域内求解一种新型（带盖板的）微带缝天线的输入阻抗,并与通常意义上的微带缝隙天线进行比较,开拓了微带缝隙天线的应用范围。     

Study of the microstrip array

The design considerations of the microstrip array, the analytical expressions of the microstrip antenna (element), the approximate admittance formula of input admittance, and two designed antenna arrays are given. Rather good results have been obtained from the main performance of the designed antenna arrays, such as sidelobe level, VSWR, cross polarization level, and gain etc.     

0.2 THz频段的光子晶体微带天线研究

将缺陷型一维光子晶体应用在微带天线上,设计了一款工作在0.2 THz 频段处的光子晶体微带天线,并且利用基于有限元法的三维电磁仿真软件 HFSS 以及软件 Origin 进行模拟仿真及作图。研究表明：光子晶体微带天线的增益可以达到9.3 dB,与普通微带天线相比增益增加了2.5 dB。并且讨论了光子晶体的周期层数对微带天线的影响,发现光子晶体周期层数为3层时,天线的回波损耗最低。然后以周期层数为3层的光子晶体微带天线为例,讨论了不同的光子晶体与微带天线的距离对天线的增益和回波损耗的影响。     

一种微带天线阵的研究

本文叙述了一种微带天线阵的设计方法。给出了微带天线(元)分析表达式以及天线阵输入导纳近似公式。设计了两个天线阵。它的副瓣、驻波比、交叉极化、增益等都是较好的。从而验证了本方法的正确性。