Microstrip antenna with metamaterial hybrid structure for 2.4 GHz

Abstract

The design and implementation of a microstrip antenna with an insertion in the feed line of a metamaterial
structure, which from a hybrid perspective combines split ring resonators (SRR) and complementary split
ring resonators (CSRR), for the band of 2.4 GHz is presented in this paper. The geometrical parameters
of the structure are varied in order to evaluate the response of resonance frequency and the radiation
pattern of the proposed antenna. The metamaterial structure adjacent to the power line produces a
considerable increase in the bandwidth concerning to that of the conventional antenna, caused by the
overlapping of the frequency bands produced by the radiant patch and the left-handed structure. The
bandwidth of the antenna with metamaterial inclusion is increased to twice the expected in the original
patch antenna, from 2.74% to values ranging from 4.55% to 6%, at expenses of gain degradation, but
without significantly affecting the coupling, and maintaining a suitable directivity. Simulation and
measured results are presented and show that the proposed metamaterial structure associated with the
transmission line of microstrip antennas is a novel way of using SRR and CSRR, which allows suppressing
the narrow bandwidth constraint.