Abstract
The method of ‘Double Grill System’1 used to focus electromagnetic radiation from an E-plane sectoral electromagnetic horn is proved to be equally useful in improving the impedance matching between the horn and the waveguide feeding system. Even a single grill arranged at the optimum position of the horn decreases the backward reflection and thereby improves the matching. The effect of two grills is proved to be simply the sum of the individual effects produced by each grill separately.