Showing papers on "Metamaterial antenna published in 1994"
TL;DR: It is shown that removal of the substrate beneath the patch can greatly improve the pattern, and a variation of this technique, compatible with monolithic fabrication, is applied to fabrication of a patch on GaAs and shows similar pattern improvement.
Abstract: Microstrip patch antennas typically have radiation patterns containing unwanted sidelobes or local minima caused by surface waves, especially when fabricated on high dielectric-constant substrates. The paper shows that removal of the substrate beneath the patch can greatly improve the pattern. A variation of this technique, compatible with monolithic fabrication, is applied to fabrication of a patch on GaAs and shows similar pattern improvement. >
79 citations
DOI•
01 Jan 1994
TL;DR: A submitted manuscript is the version of the article upon submission and before peer-review as discussed by the authors, while a published version is the final layout of the paper including the volume, issue and page numbers.
Abstract: • A submitted manuscript is the version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers.
15 citations
20 Jun 1994
TL;DR: In this paper, a multiple frequency operation technique for a microstrip antenna is proposed, in which the structure is fed by the microstrip line through an aperture coupling, which allows the antenna to operate at several discrete frequencies over a wide frequency band.
Abstract: A multiple frequency operation technique is proposed for a microstrip antenna, in which the structure is fed by a microstrip line through an aperture coupling. The technique is general and can also be applied to microstrip antennas with other feed types. It allows the antenna to operate at several discrete frequencies over a wide frequency band. >
15 citations
20 Jun 1994
TL;DR: In this paper, a passive probe-fed inverted microstrip antennas have been designed and tested and a test fixture allowed the non-destructive determination of the input impedance as a function of probe position, which offers easy integration of solid-state devices as well as other advantages over conventional configurations in hybrid microwave integrated circuits.
Abstract: Passive probe-fed inverted microstrip antennas have been designed and tested. Design formulas have been used to determine operating frequency and compared to measured results. A novel test fixture allowed the non-destructive determination of the input impedance as a function of probe position. This configuration also offers easy integration of solid-state devices as well as other advantages over conventional configurations in hybrid microwave integrated circuits. >
15 citations
TL;DR: In this article, an analysis using a generalized transmission line model (GTLM) for a probe-fed cylindrical-rectangular microstrip antenna is presented, where the equivalent circuit elements for the microstrip antennas modeled as a transmission line loaded with wall admittances are derived, and the expression for the input impedance is given.
Abstract: An analysis using a generalized transmission-line model (GTLM)for a probe-fed cylindrical-rectangular microstrip antenna is presented. The equivalent circuit elements for the microstrip antenna modeled as a transmission line loaded with wall admittances are derived, and the expression for the input impedance is given. Numerical results of the input impedance are calculated and presented as a function of the cylinder radius and the substrate thickness. Excellent agreement of the GTLM solutions with the experimental results is observed. © 1994 John Wiley & Sons, Inc.
14 citations
TL;DR: In this article, a cavity-model analysis of spherical-circular microstrip antennas is presented and expressions for the input impedance and far-zone radiated fields are derived and given.
Abstract: This article presents a cavity-model analysis of spherical-circular microstrip antennas. In this study, expressions for the input impedance and far-zone radiated fields are derived and given. Numerical results of the input impedance and radiation patterns for the antenna excited at the TM11 mode are presented, and are compared with those obtained by the generalized transmission line model and the full-wave approach to discuss the applicability of the cavity-model theory for the analysis of spherical microstrip antennas. © 1994 John Wiley & Sons, Inc.
13 citations
23 May 1994
TL;DR: In this article, a new integrated millimeterwave patch antenna HEMT receiver for imaging applications is presented, which uses a relatively thick layer of BenzoCycloButhene (BCB) as dielectric support for the antenna element, and realize microstrip based circuits.
Abstract: A new integrated millimeterwave patch antenna HEMT receiver for imaging applications is presented. The mixer element is a HEMT working in a resistive mode. We use a relatively thick layer of BenzoCycloButhene (BCB) as dielectric support for the antenna element, and to realize microstrip based circuits. At an RF of 35 GHz we obtain a minimum conversion loss of 8 dB, defined as the IF power dissipated in a 50 /spl Omega/ load divided by the available power from the patch antenna. >
10 citations
20 Jun 1994
TL;DR: The IE3D Electromagnetic Simulation and Optimization Package (ESOP) as mentioned in this paper is a general purpose CAD tool for the analysis and design of microstrip patch antennas based on a full-wave integral equation formulation.
Abstract: Discusses the use of a general purpose CAD tool, the IE3D Electromagnetic Simulation and Optimization Package, in analysis and design of microstrip patch antennas. The simulator is based upon a full-wave integral equation formulation. It has the capability of simulating planar and 3D printed structures of arbitrary shape in microwave and millimeter-wave integrated circuits (MMIC), microstrip antennas and other high frequency and high speed applications. The authors describe the simulator's application in modeling a multi-layered coupled antenna, a probe-fed circular patch antenna and an edge-fed rectangular antenna The simulator is not limited to the demonstrated examples. It can be used to model microstrip antennas of other shapes. Simulation results on the IE3D are compared to the measured results and other simulation results on literature. >
8 citations
23 May 1994
TL;DR: In this paper, the recently invented MEI technique is applied to the 3D full-wave analysis of discontinuities in microstrip, and results for a microstrip dipole antenna, open end, and right-angle bend are in good agreement with earlier work.
Abstract: The recently invented MEI technique is applied to the 3-dimensional full-wave analysis of discontinuities in microstrip. Results for a microstrip dipole antenna, open end, and right-angle bend are in good agreement with earlier work. The MEI technique is faster and more powerful than previous methods. Its advantage increases with the size and complexity of the problem. >
4 citations
20 Jun 1994
TL;DR: In this article, a new dual-band microstrip antenna is introduced, which consists of multiple layers and is planar without any structure perpendicular to the ground plane, and the antenna is easy to fabricate.
Abstract: Microstrip antennas have many advantages over the conventional antennas except their inherent narrow bandwidth. In many applications, only distinct frequency bands may be needed instead of a continuous operating frequency range. Dual-band microstrip antennas have been suggested to cover two narrow frequency bands while retaining their advantages as microstrip antennas. A new dual-band microstrip antenna is introduced. The advantage of the proposed antenna over other available dual-band microstrip antennas is its easy fabrication. The antenna consists of multiple layers and is planar without any structure perpendicular to the ground plane. Those vertical features are difficult to fabricate and are common in other dual-band microstrip antennas. The planar structure of the multi-layer microstrip antenna is attractive from a manufacturing point of view, especially for mass production using printed-circuit technology. >
4 citations
20 Jun 1994
TL;DR: In this paper, slot line feed and aperture coupled feed structures for monolithic integrated antennas have been proposed and discussed in millimeter wave range for low frequency applications, where the mutual coupling between plane radiating elements can also be used to excite an array.
Abstract: Novel EM coupled feeding structures, such as slot line feed and aperture coupled feed, are proposed and discussed. The advantages of these structures are shown in millimeter wave range for monolithic integrated antennas. For low frequency applications, the mutual coupling between plane radiating elements can also be used to excite an array. The electromagnetic energy can transfer between either of the active and passive elements. By placing a few passive elements surrounding the active elements in the center, all elements of the system can be excited and radiate energy. Examples of simplest array configurations are shown. By choosing the distance between the elements and changing the load of passive elements, the desired radiation characteristics can be obtained.
01 Oct 1994
TL;DR: In this article, a multilayer active microstrip antenna array in a spatial power combining technique by using silicon bipolar monolithic integrated circuits with high reliability is presented, and an extra gain of 8.1 dB has been measured in comparison to the passive array, including the feed network loss compensation.
Abstract: Recently, a significant amount of research has concentrated on two or three terminal devices in spatial power combining structures. This paper presents a multilayer active microstrip antenna array in a spatial power combining technique by using silicon bipolar monolithic integrated circuits with high reliability. With the advantage of a multilayer structure, the radiation patterns from the antenna side are not affected by the radiation from circuit side, and the patterns are found to agree well with theory. An extra gain of 8.1 dB has been measured in comparison to the passive array, including the feed network loss compensation. This type of array can be built at low cost and, due to the excellent unit-to-unit uniformity of the MAR amplifier, it can be the ideal building block for large microstrip phased array systems. These structures have promising applications in mobile communications, non-invasive medical imaging and other systems where radiating structures are desirable.
01 Oct 1994
TL;DR: Two new microstrip circular patches excited by a microstrip trarsmission line through an inserted coplanar section are presented and it is shown that the matching performances are improved for TM11 and TM12 modes.
Abstract: Two new microstrip circular patches excited by a microstrip trarsmission line through an inserted coplanar section are presented. The integral equation for the unknown currents on the atenna and its feeding line is solved by the method of moments in which, the triangular subdomains discretization is employed. The calculated results show that the matching performances are improved for TM11 and TM12 modes. A good agreement between our theoretical and our experimental results is obtained.
01 Oct 1994
TL;DR: In this paper, the authors presented an analysis of the electromagnetic field radiated by patches printed on inclined surfaces, which allowed to apply spatial rotations to each source and enable the choice of the phase applied to each radiator to produce a beam deflection function.
Abstract: This paper presents an analysis of the electromagnetic field radiated by patches printed on inclined surfaces. The theoretical approach allows to apply spatial rotations to each source. The computer simulation developed permits us to experiment different antenna structures and two original realisations are proposed : a 2-element array printed on two inclined planes and a 4-element array laid out on a pyramidal surface. In addition, it enables the choice of the phase applied to each radiator to produce a beam deflection function. A good accuracy is obtained between theoretical and experimental results. The aim of this study is to optimise the parameters of such antennas to achieve the desired radiation patterns, from printed phased arrays on conformal surfaces.
10 May 1994
TL;DR: The analysis of an annular ring microstrip antenna covered with lossy dielectrics is presented in this paper, where the effect of dielectric loading is not considered in the design.
Abstract: The analysis of an annular ring microstrip antenna covered with lossy dielectrics is presented in this paper It has been reported in the literature that due to dielectric loading the resonant frequency in the rectangular microstrip antenna changes The absolute value of the change increases with operating frequency, the relative permittivity and the thickness of dielectric layer This change may cause degradation in performance due to inherent narrow bandwidth of microstrip antennas if the effect of loading is not considered in the design Using variational method fractional change in the resonant frequency has been calculated for annular ring microstrip antenna and stacked annular ring microstrip antenna Experimental results are compared with numerical results and also with the rectangular microstrip antenna Eventually results are simulated on computer >
Proceedings Article•
01 Aug 1994TL;DR: With the current trend in communications towards extremely high frequencies and minimized system dimensions microstrip patch antennas have the potential to replace reflector antennas as the radiator of choice in certain applications due to their small size, ease of integration, and conformability.
Abstract: With the current trend in communications towards extremely high frequencies and minimized system dimensions microstrip patch antennas have the potential to replace reflector antennas as the radiator of choice in certain applications due to their small size, ease of integration, and conformability. However, at millimeter-wave frequencies, significant microstrip transmission line loss occurs. This loss severely affects microstrip antenna gain performance. The transmission line losses can be overcome by the integration of amplifiers throughout the feed network to form an active antenna.
20 Jun 1994
TL;DR: In this paper, the resonance problem of a superstrate-loaded annular microstrip patch on a spherical body is studied and a moment method calculation is used to solve the complex resonant frequency.
Abstract: The resonant frequency of a microstrip patch antenna is a very important factor to be determined in microstrip antenna designs It is also known that the resonant frequency is sensitive to the superstate loading and the curvature variation of the microstrip antenna The resonance problem of superstrate-loaded conformal microstrip antennas with rectangular or circular patches have also been treated previously In the present article, the resonance problem of a superstrate-loaded annular microstrip patch on a spherical body is studied A full-wave analysis and a moment method calculation are used to solve the complex resonant frequency of the microstrip patch Typical numerical results of the resonant frequency and the quality factor at the TM/sub 12/ mode, obtained from the real and imaginary parts of complex resonant frequency, are presented and analyzed >