Aperture-coupled Patch Antenna Research Articles

A passive reflect array with dual-feed microstrip patch elements

The design, development, and testing of an X-band 137-element passive reflect away capable of incorporating active devices such as transistor amplifiers is presented. In order to avoid grating lobes in the radiation pattern, the interelement spacing is minimized using dual-feed aperture-coupled patch antenna elements. Far-field radiation pattern results are presented and compared with the predicted radiation patterns. (C) 1999 John Wiley & Sons, Inc.

Extension of cavity method to analyze the aperture-coupled microstrip patch antenna with a tilted feeding line

Extension of cavity method to analyze the aperture-coupled microstrip patch antenna with a tilted feeding line

Comments on ?Dual aperture-coupled microstrip patch antenna with two superstrate layers for use in microsatellite systems?

Reference LEMA-ARTICLE-1999-006doi:10.1002/(SICI)1098-2760(19990720)22:2 3.0.CO;2-Z Record created on 2006-11-30, modified on 2016-08-08

An efficient impedance matrix calculation using the spline-type divided-difference interpolation technique

In this work, a spline-type divided-difference interpolation scheme is proposed to evaluate the impedance matrix elements in the method of moments (MoM) efficiently. This method is combined with the fast computational method of the basis-expanded and tested Green's functions introduced in a recent literature. The proposed method is applied to analyze the characteristics of a microstrip gap discontinuity and an aperture coupled patch antenna. Numerical results obtained by using this approach are in good agreement with those of other approaches.

The temperture dependence of substrate parameters and their effect on microstrip antenna performance

In the common approach to the design of microstrip antennas, the designers rely on data provided in the manufacturers' specifications, even though such specifications are confined to standard environmental conditions. In practice, the electrical parameters of the substrates may deviate from the manufacturers' data, thus making the antenna designer adopt a deficient design strategy. In the study reported, microstrip substrates were exposed to large temperature variations and their temperature dependent properties were measured in a specialized laboratory for dielectric materials. The results include plots of the dielectric constant and dissipation factor for wide temperature ranges equivalent to those in airborne applications. On the basis of this experimental data, the substrates were divided into four categories according to their dielectric constant value and its temperature dependence. Using both manufacturers' data and the measured values, a series of microstrip dual-feed aperture-coupled patch antennas were designed for the four categories of substrates and the sensitivity of their electrical performance due to temperature variations was fully investigated.

Dual aperture-coupled microstrip patch antenna with two superstrate layers for use in microsatellite systems

Dual aperture-coupled microstrip patch antenna with two superstrate layers for use in microsatellite systems

Aperture-coupled patch antenna on UC-PBG substrate

The recently developed uniplanar compact photonic bandgap (UC-PBG) substrate is successfully used to reduce surface-wave losses for an aperture-coupled fed patch antenna on a thick high dielectric-constant substrate. The surface-wave dispersion diagram of the UC-PBG substrate has been numerically computed for two different substrate thickness (25 and 50 mil) and found to have a complete stopband in the frequency range of 10.9-13.5 and 11.4-12.8 GHz, respectively. The thicker substrate is then used to enhance broadside gain of a patch antenna working in the stopband at 12 GHz. Computed results and measured data show that, due to effective surface-wave suppression, the antenna mounted on the UC-PBG substrate has over 3-dB higher gain in the broadside direction than the same antenna etched on a grounded dielectric slab with same thickness and dielectric constant. Cross-polarization level remains 13 dB down the co-polar component level for both E- and H-planes.

Optimizing a coplanar waveguide-fed aperture-coupled patch antenna for ease of manufacturing and elimination of back-radiation problems

A compact CPW-fed aperture-coupled patch antenna is modeled using the moment method code IE3D. It is shown that improvements can be made by optimizing various parameters of the antenna, such as patch diameter, CPW slot width, etc. The improvements are an increase in the bandwidth of the antenna, in the return loss across the band, as well as in the design which yield a more practical antenna in terms of construction (i.e., typical manufacturing tolerances do not significantly affect the performance of the antenna). It is also shown that a CPW-fed aperture-coupled patch antenna can be made with a ground plane which will actually improve the performance of the antenna after careful consideration of the height above the ground plane and dielectric used. © 1998 John Wiley & Sons, Inc. Microwave Opt Technol Lett 19: 391–396, 1998.

A novel integrated antenna for millimeter-wave personal communications systems

Presents the design and experimental results of a coplanar waveguide (CPW) aperture-coupled patch antenna for the extremely high frequency (EHF) band around a center frequency of 37 GHz. The antenna is implemented on a high dielectric constant substrate (/spl epsiv//sub r/=9.9), which is close to the dielectric constant of GaAs and demonstrates the feasibility of integration of such an antenna structure into monolithic circuits. The major advantage of this configuration is that the reverse side of the antenna can be used for the active and feed components. The antenna structure combines the advantages of a CPW with those of the aperture-coupled microstrip antenna and simplifies the structure of the antenna by reducing the number of metallization levels, from three down to two. In addition, this type of coupling is advantageous when applied to millimeter-wave monolithic phased arrays. A unique feed design eliminates the competition for a surface space between the antenna elements and the feed network. In addition, the ground plane shields the antenna half-space from spurious radiation emitted by feed lines and active devices. Finally, aperture coupling avoids problems associated with probe feeds at millimeter-wave frequencies, such as complexity of construction and large probe self reactances. This new type of antenna opens ways to a large number of a new possibilities such as active antennas for millimeter-wave personal communications using monolithic microwave integrated circuits (MMICs) on the same substrate and a combination of optical and radio transmission.

ALPSS: A millimetre-wave aperture-coupled patchantenna on a substrate lens

The feasibility of millimetre-wave (MM-wave) aperture-coupled patch antennas, printed at the back surface of substrate-lenses is demonstrated and the corresponding radiation characteristics are investigated. A specific realisation of such an air-lens-patch-slot-strip (ALPSS) antenna on a low-permittivity /spl epsiv//sub r/=4.0 extended hemispherical lens substrate is theoretically and experimentally characterised at 70 GHz. It is demonstrated that the ALPSS antenna exhibits clean, axially symmetric patterns of low cross-polarisation (26 dB), a directivity of 30.4 dB and the 3 dB pattern full-beamwidth remains within 6/spl deg/-5/spl deg/ between 60-80 GHz. In addition, a very-high front-to-back (F/B) ratio, of the order of 50 dB is measured at 70 GHz, despite the absence of a backing ground-plane. The ALPSS antenna is well suited for low-cost broadband point-to-point communications and collision avoidance applications.

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.

The analysis of arbitrarily shaped aperture-coupled patch antennas via a mixed-potential integral equation

A mixed-potential integral equation (MPIE) is formulated for the electric and magnetic currents on a multilayered aperture-coupled patch antenna. The integral equation is solved via the method of moments (MOM) using subsectional basis functions that allow the analysis of nonrectangular aperture and patch shapes. The input impedance and radiation efficiency of various aperture-coupled elements are calculated using the proposed technique and compared to measured results. The advantages and disadvantages of several aperture and patch configurations are discussed, and six methods of numerically de-embedding the element's input impedance are compared.

Active aperture-coupled rectangular dielectric resonator antenna

A novel configuration of an active aperture-coupled dielectric resonator antenna is reported. The design methodology is discussed and experimental results in the frequency range 4-6 GHz are presented. A comparison between an active aperture-coupled dielectric resonator antenna and an active aperture-coupled microstrip patch antenna is presented. The results presented should have useful potential applications in phased arrays and communication systems. >

Full-wave aperture coupled patch antenna

An aperture coupled patch antenna with a dual-lobed (cavity mode TM200) radiation pattern is described. The antenna employs a full-wavelength long patch fed via a butterfly-shaped aperture and a stripline feed network. This configuration provides high patch to feed network coupling and reduced back radiation. Measured return loss and pattern data are presented with proposals for several potential applications of this element.

Coplanar waveguide aperture coupled patch antennas with ground plane/substrate of finite extent

Coplanar waveguide (CPW)/aperture coupled microstrip patch antennas constructed with ground coplanar waveguide (GCPW), finite coplanar waveguide (FCPW) and channelized coplanar waveguide (CCPW) are demonstrated. The measured characteristics show that the CCPW/aperture coupled microstrip patch antenna has the largest bandwidth, whereas the GCPW/aperture coupled microstrip patch antenna has the best front-to-back ratio.

Full wave analysis for the equivalent circuit of an inclined slot on a microstrip ground plane

The problem of a radiating slot on the ground plane of a microstripline is solved using the spectral domain approach. The equivalent circuit for the configuration is obtained, and the elements are determined using the integral transformation techniques. Effects of various parameters, such as slot dimensions and inclination with the feedline, are studied. Results are compared with measurements, and reasonable agreement is obtained. The results and the approach should find useful applications in integrated circuits and aperture-coupled patch antennas. >

Spectral domain analysis of aperture-coupled microstrip patch antennas

The problem of an aperture-coupled patch antenna is studied using the spectral domain technique. The general case of a slot inclined to both the feedline and the patch is considered. The equivalent circuit for the structure is obtained and the effects of various parameters, such as slot dimensions and inclination on the resonant frequency and on the input impedance, are studied. Comparison between theory and measurement shows good agreement. The analysis could be useful in designing antennas for dual frequency operation or for circular polarisation where inclined slots could be used.

Full wave analysis of an aperture-coupled patch antenna

The problem of an aperture-coupled patch antenna is studied using the spectral domain approach. The equivalent circuit for the structure is obtained and elements are determined using integral transform techniques. Effects of various parameters, such as slot dimensions and inclination with the feedline or the patch, on the resonance frequency and on the input impedance are studied. Some results that are useful for MMIC and array antenna applications are presented.