Analysis of Linearly Tapered Slot Antennas on a dielectric substrate (original) (raw)

Moment method analysis of linearly tapered slot antennas

International Journal of Microwave and Millimeter-wave Computer-aided Engineering, 1994

An accurate Method of Moments (MoM) model is developed and implemented for the analysis of the linearly tapered slot antenna (LTSA). The model employs an unequal size reactangular sectioning for conducting parts of the antenna. Piecewise sinusoidal basis functions are used for the expansion of conductor current. The effect of the dielectric is incorporated in the model by using equivalent volume polarization current density and solving the equivalent problem in free space. The feed section of the antenna including the micro-stripline is handled rigorously in the MoM model by including slotline short-circuit and microstripline currents among the unknowns. Comparison with measurements is made to demonstrate the validity of the model for both the air case and the dielectric case. Numerical results for the effect of the dielectric permittivity are presented.

Analysis of the tapered slot antenna by the method of least squares

Iranian Journal of Science and Technology Transaction B: Engineering

This paper presents the analysis of tapered slot antenna by using the method of least squares (MLS). For this purpose first the conductor and dielectric regions are divided into suitable subsections. Then we assign the proper basis functions for their unknown currents. Therefore, the problem is changed to determining these currents: surface currents on conductor region and the polarization volume current in dielectric region of antenna. For solving the problem using MLS, we define the error function, which is based on a combination of two equations that satisfy the antenna electromagnetic conditions and then minimize it. So by computing these currents, we determine the far field radiation of the antenna. At the end of the paper, E-plane and H-plane patterns of several antennas and compare them with results of other papers that use the moment method.

Analysis of dielectric-loaded annular slot array antenna

Canadian Journal of Electrical and Computer Engineering, 2003

A method is established for the analysis of annular slot array antennas loaded with dielectric layers and fed by either radial waveguide or cavity. The analysis is based on the boundary value method. The Green's functions for each region are obtained, and then the induced magnetic current over the slots is expanded into Fourier series with unknown coefficients. Boundary conditions are applied, and a matrix equation for these unknown coefficients is obtained. For narrow slots the number of unknowns equals the number of annular slots, and an extremely rapid solution is obtained. The far-field formulation is derived using the magnetic current on the dielectric layer. The method is confirmed numerically by comparing the simulation results for sample small antennas with a commercial numerical tool (IE3D), and good agreement is achieved. It is shown that adding the dielectric layers can improve the antenna directivity. In comparison with other methods, the proposed method is very efficient, and its computation efforts depend on the number of annular slots and not the size of the antenna. As an example, for a single-slot antenna the number of unknowns to be determined is only one, while in IE3D it is more than 300. Cet article présente une approche d'analyse pour des antennes réseauxà fentes annulaires chargées avec des couches diélectriques et alimentées soit par un guide d'ondes radial ou par une cavité. L'analyse repose sur la méthode de valeurs limites. La fonction de Green de chaque région est obtenue et le courant magnétique induit sur les fentes est développé en séries de Fourierà coefficients inconnus. Les conditions limites sont appliquées et uneéquation matricielle contenant ces coefficients inconnus est obtenue. Pour des fentesétroites, le nombre d'inconnueségale le nombre de fentes annulaires ce qui permet de calculer la solution rapidement. La formulation en champéloigné est obtenue du courant magnétique sur la couche de diélectrique. La méthode est validée numériquement en comparant les résultats de simulation pour unéchantillon de petites antennes avec un logiciel numérique commercial (IE3D) et une correspondance satisfaisante est atteinte. Il est démontré que l'ajout de couches diélectriques peut améliorer la directivité de l'antenne. Comparée aux autres méthodes, la méthode décrite ici est efficace et la complexité des calculs dépend non pas de la taille de l'antenne, mais plutôt du nombre de fentes annulaires. Par exemple, pour une antenneà fente unique, le nombre d'inconnuesà calculer est de un tandis que IE3D en compte plus de ¿¼¼.

Resonant frequency of a rectangular microstrip antenna depends of the dielectric substrate parameters using the various types of current expansion function

First International Symposium on Control, Communications and Signal Processing, 2004., 2004

This work consists in characterizing a rectangular microstrip antenna while emphasizing the possibilities of various types of current expansion functions. A detailed calculation of the spectral Green's dyad, and conduction current calculated by the integral equation method via the moment's method was treated. The numerical method consists in simulating the various types of basic functions by testing convergence and by considering the effect of the parameters of the dielectric substrate such as thickness and permittivity on resonance frequency. An application of the air gap structure was also taken into account.

Linearly tapered slot antenna

1995

LINEARLY TAPERED SLOT ANTENNA by Luis Alberto Tumialan Design procedure for Linearly Tapered Slot Antennas (LTSA) has been developed and implemented using High Frequency Structure Simulator (HFSS) code based on a finite-element analysis. A CAD study of two variations of a LISA based on either a stripline or a microstrip feed has been carried out. Circular and radial stubs have been considered in these designs for an antenna operating at 10 Ghz. LTSA on a Duroid substrate fed by a stripline has been designed to operate with better than 12 dB return loss. Fabricated antenna was characterized and had even a wider response than the CAD design. Radiation patterns also were measured for this antenna. Furthermore, microstripline-fed LTSA designs were made. Further work on a low temperature co-fired ceramic substrate LTSA antennas and their arrays has been suggested. LINEARLY TAPERED SLOT ANTENNA by Luis Alberto Tumialan A Thesis Submitted to the Faculty of New Jersey Institute of Technolog...

An efficient volume integral equation technique for the analysis of tapered dielectric rod antennas

6th International Symposium on Telecommunications (IST), 2012

A computationally efficient method for the analysis of tapered dielectric rod antennas is presented. The method combines the so-called local mode theory with the method of moments. Radiation patterns for dielectric rod antennas of varying radius and different taper profiles are presented. The method is validated by comparison with the data obtained from a surface integral equation technique. Moreover, it is demonstrated that the method is applicable for different types of excitations.

Analytical Study of Corrugated Linearly Tapered Slot Antenna

The tapered slot antenna, such as Vivaldi, has been widely used due to its ultra-wideband, simple feed structure, and easy fabrication. However, the obtained radiation patterns show that conventional tapered slot antenna suffers from poor directivity in the lower part of band. To overcome this shortfall, corrugations were added on its sides. By comparing performances of the conventional and corrugated TSA it was demonstrated that by choosing a suitable corrugation pattern the directivity and beam efficiency can be improved. Our aim is to propose a wide band, higher gain Corrugated linearly tapered slot antenna (CLTSA) with relatively low cross-polarization levels and also to investigate how different patterns of corrugations will affect the radiation characteristic of linearly tapered slot antenna.

Analysis and design of radially inhomogeneous tapered dielectric rod antennas

An efficient Volume Integral Equation Method is proposed for the analysis of radially inhomogeneous tapered dielectric rod antennas (DRAs). This technique results in radiation pattern formulas that need only common integrations. Radiation patterns for DRAs of different radii and permittivities are calculated. The method is validated by comparison with the data obtained from CST Microwave Studio integral equation solver. Furthermore, radiation pattern of different permittivity profiles are evaluated and compared to achieve the optimal design parameters. The design formulas for choosing the maximum and minimum radii for different permittivity profiles are presented and compared to achieve the desired radiation parameters. An accurate formula for the calculation of antenna bandwidth is proposed. It is shown that decreasing the dielectric constant of tapered rod in the radial direction results in higher antenna gain and wider operating bandwidth.

Analysis of microstrip antennas with inhomogeneous and finite-sized substrate

2003

Microstrip antennas with inhomogeneous, finite-sized substrate and ground plane are studied. Applying the finite element-boundary integral (FE-BI) method, the electric and magnetic fields radiation on the dielectric boundary of the finite microstrip structures can be solved numerically, without the assumption of infinite substrate. The numerical result is compared with the one obtained by integral equation method for the case of homogeneous substrate, and shows good consistence with each other. The effects of inhomogeneous substrate are also studied.

Modeling Microstrip Line Fed Slot Antennas with Arbitrary Shape

Electromagnetics, 1995

A hybrid technique from the reciprocity theorem, method of moments, and triangular basis function is developed to investigate the scattering and radiation properties of microstrip line fed arbitrarily shaped aperture antennas. The electric field distribution on the arbitrarily shaped aperture is expanded by a set of triangular basis functions. S parameters and the unknown magnetic current coefficients are obtained by matching the boundary conditions on the aperture and applying the reciprocity theorem simultaneously. The rectangular, exponentially-tapered, and dumbbell slots are investigated using this technique. Inclination and offset of the aperture are introduced to improve the antenna radiation characteristics. Good agreement between experimental and numerical results has been obtained. Lastly, the advantages and limitations of this technique are discussed.