Array of waveguide-fed microstrip antennas

A low-cost Ku-band array of microstrip antennas, which is fed by standard waveguide, is presented in this paper. The 72 corner-fed square patches of the array are arranged in a 6-by-12 configuration. A novel waveguide to microstrip line transition with power divider is employed as a centre fed for the array in order to reduce the loss of the microstrip feed line. The resonant frequency of the array is 12.5 GHz and the gain was measured to be 24.3 dBi. The measurement results show good agreements with full-wave simulation. This array of waveguide-fed microstrip antennas can be used in many modern communication systems, such as a mobile radar sensor, in which the transition can be fixed as a connection between the module with a front-end waveguide and the antennas.