Broadband Circularly Polarized Printed Slot-Monopole Antenna

A slot and a monopole antenna fabricated on a single substrate can generate circularly polarized radiation over a broad band of frequencies. Appropriate power division network is used to feed the elements from a microstrip transmission line. Radiation pattern of antenna is circularly polarized in the broadside direction. Measured 3-dB axial-ratio (AR) bandwidth is 30%, and the 10-dB S11 bandwidth is 51%.