Magnetodielectric Material for VHF Antenna Devices Tunable by a Low DC Magnetic Field

This study presents the performance of a magneto-dielectric material (MDM) specially developed to enable the tunability of antenna devices operating in the VHF band. The magnetic susceptibility variation of the MDM material is controlled by a current flowing through the sample which creates a DC magnetic field inside the sample with the same symmetry as the magnetic domains. By changing the magnetization state of the MDM with a low DC magnetic field of 740 A/m, a tunability of 40% can be observed. The MDM tunability at VHF frequencies is also verified by microwave measurements for different magnetization states.