Three‐dimensional modified dipole structure with reduced resonant frequency

Abstract

A highly frequency reduction technique for three-dimensional dipole antennas has been presented using linear spiral, modified linear spiral wire-based structure and wheel on either end of dipole arm. The dipole with wheel on either end of dipole arm reduced the resonant frequency by 65.53% compared with the reference frequency at 3.83 GHz. The electrical properties of ka esteem is 0.59, which are less than the electrically small antenna limit 1. The bandwidth (-10 dB) enhanced from 11.48 for reference dipole to 17.88% without alleviating the antenna efficiency. The radiation pattern is also seen to be unaffected by the presence of those structures. To verify the simulated theory, prototypes were fabricated and complied with measured results and attained excellent agreement between them.