A triple-band circularly-polarized antenna with tuning fork shape strips

A new design of triple-band circular polarized antenna is presented. The proposed antenna is achieved using microstrip-fed with one L shape strip line, two circular strips and two circular patches. One circular strip radiates lower band, the other one covers higher band. By adding the circular patches and L shape microstrip the axial-ratio of this proposed antenna has been improved. This antenna operates in three bands which are 2.5GHz, 3.5GHz and 5.2GHz. These three operating bands can be applied for the WiMax and WLAN application. Experimental results show the proposed antenna has good return loss and circular polarization characteristics. The 10dB return loss impedance bandwidths for the band 2.5GHz, band 3.5GHz and 5.2GHz are 33%, 25% and 9.79%, respectively. The 3dB axial-ratio bandwidth are 11.4%, 6.2% and 11.8% with respect to 2.5GHz, 3.5GHz and 5.2GHz, respectively.