Abstract: A method and an arrangement for modeling antenna emission characteristics are disclosed. A slotted microwave waveguide is implemented by separate mechanical modules having slot groups respectively implemented therein. For this purpose, the modules are arranged along at least one first spatial direction, so that the modules sectionally form a part of the delimitation of the waveguide. The waveguide formed can be fed by exciting a waveguide mode and the mode propagates through the interior of the module in the waveguide formed. Screens are arranged in front of the modules, to partially cover the slot groups. Arbitrary emission characteristics can be simulated, wherein no separate feed network is necessary due to the use of a modular waveguide.