《Modeling Antenna Feeds by Electric and Magnetic》.pdf

Modeling Antenna Feeds by Electric and Magnetic Current Sheets in Conjunction with the Method of Moments 1 2 Dietmar Leugner , Heinz-D. Br¨uns 1Rohde Schwarz GmbH Co. KG , dietmar.leugner@ 2Hamburg University of Technology , bruens@tu-harburg.de Abstract— The Method of Moment (MoM) approach is often Equation (1) describes the dependency of amplitude Al due employed when regarding free space antenna problems. However to an exciting current J . there are limitations concerning modeling certain antenna feeds. Dealing with semi-infinite structures (e.g. waveguide excitation) +) − ( ( ) − + methods like FEM or FDTD are favorable due to the use of Al ∼ Zl El · J dV (1) absorbing boundary conditions (ABC) or Perfectly Matched V Layers (PML). In this paper a surface current excitations in The characteristic impedance and the electric field configu- connection with a MoM approach is introduced. A horn antenna ration of the l’