Optimized Iterative Physical Optics for EM Scattering from Large Structures
Résumé
The modelization of electromagnetic interactions
between antennas and structures is an important challenge for
systems carrying antennas such as aircrafts, satellites, frigates.
This problem deals with electromagnetic scattering from large
structures with shadowing effect and multiple scattering. A
similar problem is the Radar Cross Section computation of
large cavities. For both cases, several methods can be used, and
Iterative Physical Optics (IPO) is an asymptotic method based
on Physical Optics (PO), which has shown good results for such
kind of problems. In IPO, several techniques can be used to
take into account shadowing effects. The geometrical shadowing,
based on ray tracing, is classically used. But a recent method has
been proposed and is based on a physical approach: the shadow
radiation (around forward direction) with PO approximation.
Moreover, the IPO method can be optimized by applying an
algebraic compression, the Adaptive Cross Approximation, of the
interaction matrices of IPO between coupled surfaces. Results
show that IPO matrices can be highly compressed, without
degrading the accuracy.