Wideband design of sub-arrays in a Q-band partially-corporate fed waveguide slot array

A mesh network composed of the 40 GHz-band Fixed Wireless Access system is very essential to realize outdoor backhauls as well as fronthauls for 5G network. A 20×20-element antenna has been successfully developed in the Q-band. The partially-corporate feeding structure is adopted to divide the whole antenna into 2×2 sub-arrays for wideband operation. To further enhance the bandwidth of input matching, standing-wave fed sub-arrays of both radiating and coupling slots are investigated. By introducing the overloading technique, the bandwidth is improved from 3.1% to 7.7% especially for the sub-array of radiating slots. It is very promising to realize a broadband 20×20-element waveguide slot array by combining those redesigned sub-arrays.