Low Profile C-Band Short Backfire Antenna with a Pi-Slot Microstrip Patch Feed

This paper presents a short backfire (SBF) antenna design and simulation with a Pi-Slot microstrip patch feed. The patch-fed SBF is a more compact and lower profile design when compared to a waveguide-fed SBF. The design process is split into two steps: 1) the patch antenna was designed in isolation and 2) optimized for performance within the SBF cavity. A prototype was constructed and with this microstrip patch feed design, a measured bandwidth of 440 MHz and a gain of 13.81 dBi, which had excellent agreement with simulation.