Wideband Array Antenna with Hybrid SIGW and RGW Feeding Network

In this paper, a 4 74-element linearly-polarized wideband array antenna with a feeding network made of a combination of substrate integrated gap waveguide (SIGW) and ridge gap waveguide (RGW) technologies is proposed. The bowtie dipoles are employed as the radiation elements for the array antenna, and the bandwidth is broadened by using the concept of the tightly coupled array. By employing the hybrid feeding network combining the SIGW with the RGW, a high efficiency can be achieved with a low profile. Based on the simulations by using CST Microwave Studio, the proposed 4 74 array antenna exhibits a relative impedance bandwidth of 34% from 22.7 to 32 GHz, with a maximum gain of 18 dBi