Slot Antenna Array with Compact Feed based on a Substrate Integrated Fabry-Perot Cavity

This work presents a new technique for designing the feeding circuit of a slot antenna array. The radiating slots are arrayed on one side of a single layer printed circuit board. The array is excited via a compact substrate integrated Fabry-Perot cavity (FPC). At the resonance of the cavity, the outgoing field is quasi-uniform and permits a transverse electromagnetic traveling-wave mode through the array at 8 GHz frequency. The FPC is fed by a microstrip line using a transition made of a metallic via and a coplanar-waveguide (CPW) line. Based on this design principle, the array is optimized. This design offers a simplified and smaller feeding circuit than conventional antennas that use multiple dividers or combiners. Simulated results validate the proposed approach. These results illustrate acceptable impedance matching, and an 18 dB gain. This technique demonstrates a feasibility step in antenna engineering.