A method for the design of miniaturized suspended plate multiband antennas

This paper presents a method to design suspended plate multiband antennas with reduced size and enhanced performance. A periodic folding algorithm is applied over a thin conducting plate and the resultant antenna is fed by a coax probe through a thin dielectric substrate of low permittivity. The effectiveness of the method is demonstrated with the design of a compact periodic suspended plate multiband antenna on 1-mm thick FR-4 substrate. The antenna comprises an additional vertical substrate etched to a non-radiating edge of the plate and two asymmetric shorting pins. Numerical results predict a 6-band resonance below -10 dB of reflection coefficient with all resonant frequencies spanned within the 1-6 GHz spectrum range. Numerical results also show that the sizes of the ground plane and the dielectric substrates have little effect on the performance of the antenna.