In this paper, a compact geometry of a circularly polarized (CP) antenna with a simple feeding technique for exciting orthogonal components is presented. In the proposed technique, a broadband CP is achieved by using a parasitic strip of an inverted bracket shape and placing it capacitive to the straight microstrip line. The initial horizontal and vertical components of the circular polarization generated by the parasitic strip are further tuned by using an asymmetrical configuration of the coplanar waveguide (CPW). To obtain the best performance in terms of the antenna size reduction, impedance matching, and axial ratio bandwidth (ARBW), all geometrical parameters of the antenna are adjusted through rigorous EM-driven optimization. The total size of the proposed antenna after optimization is only 27 mm × 28.8 mm. A wide impedance bandwidth up to as 65% (3.6 GHz-7.1 GHz) along with 49 % (3.6 GHz to 6.0 GHz) axial ratio bandwidth (ARBW) is achieved. The average realized gain the proposed antenna within the CP operating band of is 3.3 dB. A bidirectional radiation pattern is achieved with the opposite sense of polarization in the ±z-direction.
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