This paper describes the design and experimental characterization of a circular polarized printed antenna for dual-band WiFi operation at 2.45 GHz and 5.10 GHz. The patch design is based on a combination of slits loading and gap-coupling applied to a disc patch in order to enhance the radiation performances in terms of polarization purity and bandwidth at the two operation frequencies. Experimental validations confirm a maximum gain around 6.0 dB for both 2.45 and 5.10 GHz, as well as an axial ratio as low as 0.5 dB and a return loss exceeding 15 dB on the operating frequencies. These characteristics are suitable for operationing in IEEE802.11x networks.
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