An antenna is fabricated using an M-type hexaferrite, such as a tin (Sn) and zinc (Zn) substituted M-type strontium hexaferrite (Sn/Zn-substituted SrM: SrFe12−2xZnxSnxO19), thereby enabling antenna miniaturization, broad bandwidth, and high gain. In one embodiment, an antenna system has a substrate and a chip antenna formed on the substrate. The system also has a conductive radiator contacting the chip antenna, and the chip antenna comprises an M-type strontium hexaferrite for which Fe cations are substituted with tin (Sn) and zinc (Zn) to achieve soft magnetic properties for the antenna. Thus, the coercivity and permeability are lower and higher, respectively, than those of pure SrM. Such fabricated hexaferrite chip antennas have broadband characteristics and show good radiation performance at various frequencies, including in the GHz frequency range.