Performance Evaluation of Triple-band Microstrip Antenna using Hybrid-SRRs on Truncated Ground Plane

A single-band monopole antenna, transformed into a triple-band antenna for S-band and C-band applications is reported in this paper. This transformation is done with the help of two different hybrid SRR unit cells, which are embedded on the truncated ground plane of the antenna. These hybrid SRR unit cells are created by combining square split ring and circular split ring into two different configurations. Simulated results are in coherence with the measured results and analysis is provided to evaluate the efficacy of the design. This analysis can be used to estimate the usefulness of metamaterial unit cells in generating multiple frequency bands. The operating frequency bands measured are 2.72-2.83GHz, 3.54-4.35 GHz, and 4.72-5 GHz respectively. These bands are being used in the mid-band frequency range of 5G communication in many countries. The developed antenna is miniaturized to the size of 0.19 lambda(0)x0.25 lambda(0) (lambda(0) is the free space wavelength at 2.72 GHz). Two objectives i.e., miniaturization and multi-banding are fulfilled in a single design. The introduction of different hybrid SRR unit cells at defective ground plane causes multi-banding and resonance of a unit cell at a lower frequency leads to an increase in the effective electrical length of the antenna without increasing its physical size. The metamaterial characteristic of the unit cells is also verified in the article.