Research on the influence of cylindrical dielectric capsulation on dipole antenna

The influence of cylindrical dielectric capsulation on the input and output performance of a 2.5 GHz half-wavelength dipole antenna has been researched. A model of the capsulated antenna is given and simulations are conducted according to different numerical values of parameters involving the capsulation dimensions and dielectric constant. The antenna gain, directivity and reflection coefficient are calculated via the finite element method in HFSS. Spline interpolation and polynomial curve fitting are applied to construct diagrams illustrating the capsulation characteristics. It is shown that the input and output performance of the half-wavelength dipole antenna is, in general, sensitive to variations of the capsulation. The analysis and simulation facilitate further research on the structural design and optimization of a capsulated antenna.