Flexible isotropic antenna using a split ring resonator on a thin film substrate

Isotropic antennas on thin Kapton films have been designed using a small dipole antenna and a split ring resonator (SRR) for 2.4 GHz applications. The size of the designed antenna is 0.24λ × 0.24λ and the electrical size (ka) is 0.75. The antenna has an isotropic radiation pattern and the maximum gain is 1.83dB. If the antenna is attached on a curved surface, the operating frequency increases as the radius of the surface decreases since the electrical length of the antenna decreases. When the radius of the surface is 0.04λ, the volume of the cylindrical antenna is 0.24λ × 0.08λ × 0.08λ and the radiation pattern is still isotropic.