A Beamforming-Network-Based Four-Squint-Beam Array Antenna for Ceiling-Mount Access Point

A novel beamforming network (BFN) applicable to a 2 × 2 array antenna is proposed in this letter. It provides four coexisting squint beams tilted away from the array's boresight and is particularly suitable for ceiling-mount access points. The principle novelty lies in the BFN, which comprises four rat-race couplers and two 90° delay lines. With this circuit, four phase offsets, which are -90°, 0°, 0°, and 90°, can be assigned to the four antennas from the four beam ports in a rotating order. To demonstrate its applicability to ceiling-mount antennas, a 2 × 2 clover-leaf array was devised. Simulations and measurements were conducted to verify the tilting beam feature. A comprehensive coverage with elevated gains can be achieved by merging receptions from the four beams, which are applicable to up-to-date multitransceiver devices.