In this work, the full-wave method is used for computing the resonant frequency, the bandwidth, and radiation pattern of High temperature superconductor, or an imperfectly conducting annular ring microstrip, which is printed on uniaxial anisotropic substrate. Galerkin's method is used in the resolution of the electric field integral equation. The TM set of modes issued from the cavity model theory are used to expand the unknown currents on the patch. Numerical results concerning the effect of the anisotropic substrates on the antenna performance are presented and discussed. It is found that microstrip superconducting could give high efficiency with high gain in millimeter wavelengths. Results are compared with previously published data and are found to be in good agreement.

Abstract-In this paper, synthesis of superconducting circular antennas mounted on circular array is designed by the combination of a method based on particle swarm and a full-wave method. Fullwave method is used for computing the resonant frequency, bandwidth, radiation pattern and the efficiency of a perfectly superconducting, or an imperfectly conducting circular microstrip, which is printed on isotropic or uniaxial anisotropic substrate.Particle Swarm Optimization (PSO) has been used to obtain the minimum side lobe level (SLL) of circular array, by varying elements excitations and/or positions. Numerical results concerning the effect of the parameters of substrate and superconducting patch on the antenna performance are presented and discussed. It is found that superconducting circular antenna could give high efficiency. Also, results show the efficiency of PSO in producing desired radiation characteristics and are in good agreement with previously published data.

In this paper, multiple signal classification and estimation of signal parameters via rotational invariance technique (ESPRIT) algorithms are proposed to estimate the direction of arrival (DOA) of multiple incident signals under known mutual coupling among elements of the antenna array. These algorithms use the same subspace based techniques to achieve the separation of the eigenvectors into two subspaces: the signal space and the noise space. However, ESPRIT only uses the signal space. The performance of subspace based DOA estimation algorithm is evaluated using uniform linear arrays of dipole elements. The simulation results show the exact number of samples and elements, signal‐to‐noise ratio and spacing between the antennas elements used are the most important parameters in the algorithms, to sustain the accuracy of the DOA of the incident signals. The problem of calculating mutual coupling coefficient of the array elements is formed into a matrix has been considered. It is shown from the simulation results that the performance of the DOA estimation techniques considering the mutual coupling effect can be improved by the proposed compensation method. The different results obtained are in good agreement with those of the literature.

Abstract-An analytical model is presented to investigate the performances of an annular-ring patch etched on a two layered dielectric substrate and is covered by a dielectric superstrate, by using a full-wave spectral domain technique in conjunction with the complex resistive boundary condition. Galerkin's method and Parseval's theorem are used to obtain the resonant frequency and bandwidth. To validate the theoretical results, a study has been performed for an annular-ring patch on a single layer, with air gap, and cover layer. The computed data are found to be in good agreement with results obtained using other methods. Variations of the resonant frequency and bandwidth with the high temperature superconducting (HTS) thin film are also presented. The proposed model is simple, accurate and thus should help a designer for practical applications.

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Abstract:In this work, we demonstrate via numerical simulation the general design for one dimensional photonic crystal (1D-PC). In the design procedure, the transfer matrix method and Bloch theorem are used to determine the transmission coefficient and dispersion relation of (1D-PC) structure for both TE (transverse electric) and TM (transverse magnetic) modes. Results obtained showing the effect of the filling factor as well as the incident angle on the photonic band gap width. The analysis is carried out using MATLAB software tool. The accuracy of the analysis is tested by comparing the computed results with measurements published data.

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