Conformal Slot Antenna Array Fed by Metal Gap Waveguide/Cavity for Multi-Beam Radiation

A two-dimensional circularly cylindrical phased array of waveguide slot antennas is presented for beam steering applications. Each column waveguide (WG) slot array is equally spaced to radiate linearly polarized electromagnetic fields, which are horizontally conformal to a circular boundary for circular beam steering. The beamforming network (BFN) is designed interior to the circular boundary, which is formed by metal gap WGs and cavities for high-efficiency array excitations. Due to the noncontact nature of the gap WG BFN to the WG slot antennas, the WG BFN can be rotated by a motor to switch the beam directions, extending the coverage range. This antenna array is realized at Ku-band for microwave links with low radiation losses. Full-wave simulation results are shown to demonstrate the radiation characteristics and validate the feasibility.