Waveguide Based Butler Matrix with Dual Beam Slotted Antenna at 28 GHz

This paper presents a fully waveguide Butler Matrix beamforming with dual beam waveguide slotted antenna. The Butler Matrix is designed using a low loss waveguide with coupling control method on each coupler and crossover. A 4x4 matrix is designed and the outputs are connected to four elements of slotted waveguide antennas. Slots are positioned on both broadwalls, enabling dual-beam functionality. The beam is directed at ±13.45° and ±49.7° for different input port.