Miniature antenna based on magnetoelectric composites

The design and characterisation of a miniaturised 100 MHz antenna based on magnetoelectric (ME) composites are discussed. Ferrite - ferroelectric composites with high and equal permeability mu_r and permittivity epsiv_r have been synthesised and used as the substrate for a microstrip antenna. The composite also facilitates impedance matching to free space. A sample of nickel zinc ferrite and bismuth strontium titanate prepared by ceramic processing and with mu_r = epsiv_r has been used. Scattering parameter data indicates an antenna miniaturisation factor of 7-10 at 100 MHz, in agreement with theory.