Optimization of radiosonde antenna radiation pattern

The vertical dipole antenna for atmospheric radiosonde with vertically tilted and horizontally isotropic radiation pattern is developed. The problem is solved by insertion of metal disc into antenna design. The model of the developed antenna for frequency band around 403 MHz is researched by means of computer analysis. The influence of the perforation of antenna disc on its characteristics is considered. The possibility of tilting the radiation pattern by 30 degrees without affecting the antenna input parameters is shown.