Single-feed triangular microstrip antenna with compact circular polarization

The single-feed CP designs of compact triangular microstrip antennas with a triangular slot have been demonstrated. Simply by inserting a narrow slit of proper length at the bottom edge or at the tip of the embedded triangular slot, CP radiation can easily be achieved by using a single probe feed. Results indicate that, at a fixed operating frequency, the proposed designs can have good CP radiation characteristics with a reduced antenna size of about 30% compared to the regular-size CP design using a simple triangular patch.