Title :
Design, Fabrication, and Measurement of a One-Dimensional Periodically Structured Surface Antenna
Author :
Stuart, Howard R.
Author_Institution :
LGS, Bell Labs. Innovations, Florham Park, NJ, USA
Abstract :
A radiating periodically structured surface resonator is studied from the point of view of minimizing the radiation Q-factor of the fundamental mode of the resonator. Structures with a one-dimensional array of gaps are considered, where the resonant mode is formed by the capacitance of the gaps resonating with the inductance of the conducting pathways. An eigenmode study of a range of designs of identical size demonstrates that increasing the number of gaps does not lower the Q . The results show that this family of resonators has a radiation Q that is typically ~ 2 × lower than a simple patch antenna occupying the same electrical volume. The improvement in Q is accompanied by a corresponding reduction in the directivity gain of the broadside radiation, confirming the inherent bandwidth/directivity trade-off in radiators of identical size and shape. A three-period resonator is made into an antenna by driving it from underneath the surface. The fabricated antenna has dimensions of 0.40 λ × 0.26 λ, a thickness of λ/34, and a measured 10 dB return loss bandwidth of 12.4%, ~ 4.5 × wider than a simple patch antenna of the same size. These antennas can replace patch antennas in applications demanding the widest possible impedance bandwidth from a thin antenna.
Keywords :
Q-factor; antenna radiation patterns; eigenvalues and eigenfunctions; microstrip antennas; resonators; broadside radiation directivity gain; eigenmode study; loss 10 dB; one-dimensional array; one-dimensional periodically structured surface antenna design; patch antenna; radiating periodically structured surface resonator; radiation Q-factor; return loss; three-period resonator; Antenna measurements; Bandwidth; Capacitance; Fabrication; Inductance; Loss measurement; Patch antennas; Resonance; Shape; Thickness measurement; $Q$-factor; Periodic structures; resonant antennas;
Journal_Title :
Antennas and Propagation, IEEE Transactions on
DOI :
10.1109/TAP.2010.2052541