Radiation pattern of an electrically long, sleeve choke-loaded monopole using magnetic and dielectric beads

The radiation pattern of a sleeve choke-loaded monopole can be modified to resemble a quarter-wavelength monopole with small radii chokes with the addition of magnetic and dielectric beads. An electrically long monopole loaded with a sleeve choke and magnetic and dielectric beads is given. Magnetic and dielectric beads are placed adjacent to the sleeve choke. The return loss and radiation pattern for this structure were computed using Ansoft's finite element package, HFSS.