Miniature antenna based on magnetoelectric composites

The design and characterisation of a miniaturised 100 MHz antenna based on magnetoclectric (ME) composites are discussed. Ferrite-ferroetectric composites with high and equal permeability mu(r) nd permittivity epsilon(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) = epsilon(r) has been used. Scattering parameter data indicates an antenna miniaturisation factor of 7-10 at 100 MHz, in agreement with theory.