Mohammed Titaouine

Analysis of quasi-square open ring frequency selective surface using the Wave Concept Iterative Procedure

This work presents the analysis of quasi-square open ring frequency selective surface, FSS, using the Wave Concept Iterative Procedure, WCIP. As this structure presents a strongly dependence of the electric field polarization, different frequency bands can be selected. Furthermore, there is a coupled strips region and its length can be used for frequency adjustment. The behavior of the electric fields and how it can affect the resonant frequency is discussed. Numerical and measured results for the frequency of resonance are compared and a good agreement is observed.

Electromagnetic modeling of planar almost periodic structures

After the presentation of almost periodic structures and their interest in circuits, antennas and diffraction, one focus the study on bidimensional structures which have periodic cells but non periodical patterns inside the cells. The bi-dimensional leaky waves antennas array with a central feed and the circuit in package made up with metallic via in an arbitrary arrangement are particular cases of almost-periodic structures. Two numerical methods are used for modeling the almost periodic planar structures: the method of moments and the wave concept iterative procedure.

Analysis of tapered micostrip patch antenna by the Wave Concept Iterative Procedure

This work presents the analysis of the tapered microstrip patch antenna by the Wave Concept Iterative Procedure, WCIP. The resonant frequencies variation with the patch dimensions and how to include it as project flexibility is discussed. The behavior of the electric fields is presented and analyzed for the first two resonant frequencies. Numerical and measured results are compared and a good agreement is observed.

Tunable FSS simulation using WCIP method for multiband and dual polarized applications

A novel multiband-operating and dual polarization frequency selective surface (FSS) for radomes applications for radar stealth is proposed. The design is based on an open metallic ring with coupled end strips. The proposed FSS rejects electromagnetic waves at frequencies 9.1, 10.8 and 11.5 GHz simultaneously with bandwidths of 900, 100 and 200 MHz, respectively, when the structure is excited by the x-polarized plane wave, and it rejects at one frequency 7.3 GHz with bandwidth of 1000 MHz, when the structure is excited by the y-polarized plane wave. Frequency tenability is provided by varying the length of the FSS coupled strips and the left edge of vertical U-shaped metallic strip composing the FSS structure. An enhancement of the x-polarized FSS bandwidth from 900 to 1500 MHz and from 200 and 100 to 500 MHz has been achieved. Simulation results obtained by the WCIP method were compared with the simulation results obtained by the COMSOL multiphysics software 4.3b and with the measurements. A good agreement of the results was observed.

Characterization of dual band and double polarized notched metallic ring FSS and their equivalent parallel metallic strip structures

ABSTRACT In this work three rejecting band filters for multi band and dual polarization applications are proposed. The first proposed structure is an open quasi square FSS with a centered notch. The variation of the notch position to the left leads to the tenability of frequencies in both directions of polarization. The addition of a second notch has resulted in a third frequency in the y direction maintaining two resonant frequencies in the x direction. The structures are simulated by the Wave concept Iterative Method and the Comsol Multiphysics software 4.3b. In the second part of this paper a new approach is proposed to obtain an equivalent FSS structures based on non-coupled parallel metallic strips. The new equivalent FSS structures allow the frequency adjustment by the variation of the corresponding strip lengths. The results obtained by the WCIP method and measurements are compared and a good agreement is obtained.

Analysis of double layered frequency selective surface based on WCIP-SM technique

In this paper a technique combining the wave concept iterative method WCIP and the scattering matrix SM method is used to analyze a double screen rectangular conducting patches FSS structure, the WCIP method is used to obtain the scattering characteristics of the two FSS then the scattering matrix technique is applied to obtain the total scattering characteristics of the two level FSS structure. The WCIP-SM results are successfully compared with numerical and experimental results presented in literature.