A novel reduced size CPW-coupled patch antenna topology for millimeter waves applications

A novel reduced size patch antenna on a single layer substrate is investigated. The antenna structure developed combines the advantages of a CPW (coplanar waveguide) with the advantages of an aperture-coupled microstrip antenna, and simplifies the structure of the antenna by reducing the number of metallization levels from 3 to 2, thereby making the integration of active devices easier. Insetting high dielectric constant slits into the patch reduces the size of the coplanar waveguide fed patch antenna. The slits play a role not only in lowering the center frequency, but also in fine-tuning the proposed antenna together with the length of the aperture (slot). The proposed antenna with slits has a lower center frequency than the conventional structure, suggesting that the antenna size can be reduced as much as 14.3%. The structure simulations of the proposed antennas have been performed to obtain impedance matching and to investigate the effects of the slits.