Monopole Antenna Miniaturization with Magneto-Dielectric Material Loading Combined with Metal Parasitic Element

Abstract

In this paper is shown a new way to use Magneto-Dielectric Materials (MDM) in order to miniaturize monopole antennas. It is proposed to load an antenna with MDM to use the relative permeability to achieve the first 17% miniaturization rate. Then, in order to achieve better miniaturization, it is proposed to add metal parasitic plates on both sides of the material to use the relative permittivity to ensure capacitance useful to shift the antenna’s resonant frequency. By combining material loading, metallic plates’ capacitances and matching circuit designed with the real frequency technic, an antenna’s frequency shift from 350 MHz to 200 MHz is achieved corresponding to 43% of height reduction. A matching circuit has been designed to match the antenna at −5 dB. The obtained frequency bandwidth is 15% (185–215 MHz) with a realized gain of over −2.5 dBi.