The WCIP Method: Theory and Applications (pp. 143-176)
Authors: (M. Titaouine, N. Raveu, A. Gomes Neto, H. Baudrand, Faculty of Technology,University of Batna. LMSE Laboratory, University Center of Bordj Bou-Arréridj, Algéria, and others)
Abstract: The theory of the Wave Concept Iterative Procedure (WCIP) is presented. Based on
bounded operators, the convergence of the WCIP method is insured independently of the
planar circuit. Moreover, the coupling between the elements of the same circuit is
inherently taken into account by the WCIP method since the scattering operator deals
with the interface as an entire entity. The WCIP method consists of two main steps: the
scattering of the incident waves at the interface and the reflection of the scattered waves
at the closing ends of the box enclosing the planar structure. Since the reflection
coefficient is known to be diagonal in the modal domain, the reflected waves are
projected on the box modes (TEM, TEmn, TMmn) in order to determine the modes
amplitudes. The Fast Modal Transform pair FMT/FMT-1 is used to pass from the spatial
domain to the modal domain in order to calculate the modes amplitudes of the scattered
waves and from the modal domain to the spatial domain to recover the incident waves.
Being based on the two dimensional Fast Fourier Transform, the FMT/FMT-1 transform
results in a reduction of running time and space memory.
The WCIP method has been applied to many structures such as antennas, integrated
circuits ICs, Radio Frequency Integrated Circuits RFICs, Frequency Selective Surfaces
When printed antennas characterization is considered, the box influence on the
WCIP final results is avoided by the superposition of the odd and even solutions,
determined by enclosing the planar structure respectively in an electric and magnetic box
the final solution is obtained.
The multilayer structures encountered in stacked topologies of IC‘s and RFICs are
seen by the WCIP method as a two layers structures once the interlayer operators are determined. FSSs finding their applications as spatial filters for antenna and infrared
applications…are analysed once the unit cell is hypothetically limited by periodic walls.
Active elements can be added to the planar structures to end with an electronically
controlled electromagnetic behaviour of the structure. Active elements and passive
elements are inserted as surface impedances and a load operator is determined to be
added to the iterative procedure. Anisotropy of dielectric layers, resulting in less loss, are
taken into account by the WCIP method once the equivalent dielectric layer is
determined. The use of anisotropic layers loaded structures allow flexibility in controlling
the scattering characteristics.
The macropixel approach is employed in conjunction with the WCIP method to
study the coupling of circuits elements enclosed in the same box, using a diakoptics
WCIP results for various applications are compared with measured results and
simulation results of literature and good agreements are obtained.