T. Ozdemir et Jl. Volakis, TRIANGULAR PRISMS FOR EDGE-BASED VECTOR FINITE-ELEMENT ANALYSIS OF CONFORMAL ANTENNAS, IEEE transactions on antennas and propagation, 45(5), 1997, pp. 788-797
This paper deals with the derivation of the edge-based shape functions
for the distorted triangular prism and their applications for the ana
lysis of doubly curved conformal antennas in the context of the finite
element method (FEM). Although the tetrahedron is often the element o
f choice for volume tessellation, mesh generation using tetrahedra is
cumbersome and central processing unit (CPU) intensive. On the other h
and, the distorted triangular prism allows for meshes which are unstru
ctured in two dimensions and structured in the third dimension. This l
eads to substantial simplifications in the meshing algorithm, and many
conformal printed antenna and microwave circuit geometries can be eas
ily tessellated using such a mesh. The new edge-based shape functions
are first validated by computing the eigenvalues of three different ca
vities (rectangular, cylindrical, and pie-shell). We then proceed,vith
their application to computing the input impedance of conformal patch
antennas on planar, spherical, conical, and other doubly curved (ogiv
al) platforms, where the FEM mesh is terminated using an artifical abs
orber applied conformal to the platform. Use of artificial absorbers f
or mesh termination avoids introduction of Green's functions and, in c
ontrast to absorbing boundary conditions, a knowledge of the principal
radii of curvature of the closure's boundary is not required.