Design of An Axial Mode Helical Antenna Using Ferrite and Dielectric Loading

An axial mode helical antenna loaded with magneto-dielectric ferrite and dielectric polyethylene terephthalate (PET) is presented. The helical antenna radiation is circular polarization over a wide frequency range and the volume reduction of helical antenna is 37.5% in contrast with air-core antenna. Moreover, by adjusting the proportion between ferrite and PET, the helical antenna obtains impedance bandwidth of 86.8% from 1.76 to 4 GHz, 3 dB axial ratio bandwidth of 50% from 2.4 to 4 GHz, and a maximum realized gain of about 8.8 dBi.