Broadband rod antenna of limited counter balance wt. - effected by including RL circuit in upper end of rod

摘要

The broadband rod antenna is designed so that its radiation pattern is not affected by the counter balance weight. This is achieved by damping the upper part of the rod by inserting a parallel circuit consisting of a resistor and inductor. The antenna's supply point is connected to the supply via a matching transformer with stepped wave impedance. The resistor is divided into two or more parts to ensure adequate cooling. The two or more resistance elements are connected to coaxial lines of suitable wave impedances such that a freq-independent real impedance appears in the branch parallel of the inductor.