Achieving tetra band performance in simple dielectric and in metamaterial filled patch antennas

In this contribution, we have proposed a robust technique to achieve tetra-band performance in both conventional dielectric (elliptical shape) and also metamaterial loaded (rectangular shape) patch antennas. Incorporation of symmetric slots over the patch in both type of antennas have been shown here by using the concept of additional modified modes and perturbation approach. At first, we have shown that if and only if, elliptical shape patch antenna is properly optimized along with symmetrical slots over metallic patch, it is possible to achieve satisfactory four- band performance without the aid of any complex procedure currently present in literature. Later, we have reported a compact metamaterial loaded tetra band rectangular patch antenna to achieve extremely high gain and directivity performances for all the four bands, which may not be possible with conventional dielectric antennas.