Structural slotted waveguide antennas for multirotor UAV radio altimeter

Z-slots are presumed to offer a structural advantage over conventional inclined slots for narrow wall slotted waveguide antennas, in that the corners of the rectangular waveguide are not cut and consequently will not weaken a structural tube as much. Initial structural simulations are shown to confirm this assumption. This slot configuration was also further investigated as radiating slots in standing wave type slotted waveguide antennas. Fan-beam antennas having 10 to 30 slots were successfully designed for 10GHz using a commercially available antenna simulator, having directivities from 16 to 21dBi and aperture efficiency of 60%.