Design of an adaptive subarray antenna for multibeams wireless small cell backhaul in mmWave

This paper presents the design of an adaptive subarray antenna for multi-beams wireless small cell array backhaul in mmWave (above 6GHz).This structure consists of 2x2 dual polarized driven cross patch each has surrounded by four parasitic elements that can be connected if necessary to the ground plane by a pin to act as directors/reflectors to the ground plane to act as directors/reflectors. The proposed structure excited by 4 Wilkinson dividers power feeding system can generate three high gain beam patterns with 3dB total beam-width of 153° with a maximum total gain around 10dBi at frequency 10.4GHz in each orthogonal plane, following a combination of the ports to be excited and the location of the short-circuit on the parasitic elements surrounding the radiating elements. To validate the concept, a prototype is fabricated and an excellent agreement is obtained between the simulation and experimental results in terms of the return loss, isolation and the radiation pattern of the planar subarray antennas.