Design of broadband circularly polarized microstrip patch antenna which is coupled by two H-shaped apertures is presented in this paper. Based upon the proximity coupling feed by the Wilkinson power divider, the proposed antenna can have a standing wave bandwidth of about 47.5% and the axial-ratio value within 3dB is about 50%. The front-to-back ratio of the antenna radiation pattern is better than #61485;21dB, which indicate the realization of the good circularly polarized and low backward radiation level characteristics.
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