Microstrip slot array with shorting via wall

In this paper, a novel type of microstrip slot antenna is proposed for mm-wave applications. Shorting vias are introduced around the radiation slots to suppress the excitation of surface waves. As an example, a single element and a 2x2 array of microstrip slot antenna are designed at 30 GHz. Simulations show the designed single element and 2x2 array can achieve a gain of 8.1 dBi and 11.3 dBi, respectively. The simulated -10 dB bandwidth is about 2.7 GHz, or 9% relative bandwidth.