In this paper, a CPW-fed compact metamaterial-inspired monopole antenna is proposed for Industrial, Scientific and Medical radio band (ISM, 2.4-2.483 GHz). The proposed antenna consists of a T-shaped patch and a set of split ring resonators (SRRs). The miniaturization is attained after loading SRRs in proximity to the T-shaped radiator, which makes the antenna structure electrically small. The measured fractional bandwidth of the antenna is 4% (2.42-2.52 GHz), and its size is 0.22λo× 0.098λo×0.013λo. In addition, the electrically equivalent circuit of the proposed antenna is modeled, and the resonant frequency is calculated by using an analytical approach. Also, the permeability plot of SRRs is extracted using Nicolson Ross weir method. The measured peak gain and radiation efficiency of the antenna are obtained as 1.76 dBi and 78.5%. The simulated results and measured results are found in a good agreement.
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