Control of Antenna Beam Width

Several methods controlling antenna beam- widths are briefly proposed for aperture widths approximately equal to one wavelength, which can be used as primary feeds to create the fan beams of radar antennas. The mouth modifications can improve the radiation patterns and input impedance matching. It is possible to narrow radiation pattern, and therefore to increase the gain. On the other hand, similar modifications are advantageous for dual orthogonal polarization or octave frequency bandwidth operations of aperture antennas such as horns. The proposed modifications have been performed for hoghorn. The measurements of conventional and modified hoghorn designs are compared in detail.