A small meander VHF & UHF antenna by magneto-dielectric materials

Nowadays, new digital multimedia broadcasting services like DAB (digital audio broadcasting) and T-DMB (terrestrial digital multimedia broadcasting) have been realized through VHF band and will provide large opportunities for mobile business. The antenna size for DAB/T-DMB must be too large to be assembled in mobile equipments because a quarter wavelength of VHF band in vacuum (/spl mu/r=1, /spl epsiv/r=1) is about 40cm. To solve this problem, we have developed new small antennas consist of meander conductive metal pattern and magneto-dielectric (/spl mu/r=1, /spl epsiv/r=1) layers. The ferrite resin composite material and ferrite film have been used for magneto-dielectric layers. The results of electromagnetic field simulation showed that resonant length of an antenna must be 1/(/spl mu/r /spl times/ /spl epsiv/r)/sup 0.5/, and the resonance frequency of a magneto-dielectric antenna was about 30% of an antenna by dielectric materials.