A compact circularly polarized antenna using a wide L-shaped slot and a microstrip feedline is proposed. The measured results demonstrate that the antenna has an axial ratio (AR) < 3 dB bandwidth ranging from 5-8.5 GHz and an S11 < -10 dB bandwidth ranging from 4-8.6 GHz. The antenna is very simple, composed of an L-slot and a microstrip feedline placed beneath and to the edge of the L-slot. The size of the antenna is 20 x 20 mm2 which is attractive for compact wireless devices that operate in C-band. The antenna has very low cost and does not require: a large size, truncated corners, reflecting surfaces, complex feeding structure, and via connections, which increase fabrication cost and design complexity.
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