Electrically Small Quasi-Isotropic Planar Antenna Loaded with Split-Ring Resonator

This paper presents an electrically small quasi-isotropic dipole antenna loaded with Split Ring Resonator (SRR) for applications in the 2.4GHz band. In this work, a near field parasitic element (NFPE) i.e., SRR is loaded beneath the electric dipole to generate quasi-isotropic radiation characteristics. The electric dipole (i.e., curved dipole) and NFPE are arranged to achieve a uniform radiation pattern in spatial coverage. Here, the SRR exhibits patterns like magnetic dipole which is orthogonal to the radiation pattern of an electric dipole. The overall dimension of the antenna is 0.13λX0.13λ mm2. The fabricated prototype of the proposed electrically small antenna(ESA) is measured to validate its performance. The measured S11 response shows good agreement with the simulated one. The fabricated prototype offers 48MHz bandwidth centered at 2.43GHz. The proposed antenna offers a quasi-isotropic pattern with 90% radiation efficiency over the operating band, ranging from 2.41 to 2.458GHz.