Frequency and Band Reconfigurable Circularly Polarized Square Ring Slot Monopole Antenna

In this paper, a frequency and band reconfigurable grounded square ring slot monopole antenna is presented for the circular polarization. A coplanar waveguide fed monopole excites the grounded slot. Two inverted L-shaped stubs are placed in the opposite corners of the grounded slot, resulting in the generation of circular polarization. Embedding an RF switch within one of the L-strips, it is possible to achieve a frequency reconfigurability. Additionally, by introducing a switchable vertical stub, the band reconfigurability can also be achieved. The proposed design concepts are validated using full wave EM simulation and measurement on a fabricated prototype.