Tunable high-frequency antenna

Abstract

Tunable high-frequency antenna which has, over its length dimension, a number of built-in switches by means of which antenna sections are defined and frequency tuning takes place through antenna length matching by disconnecting and connecting said antenna sections. The antenna comprises a pair of parallel wire conductors, incorporated in series with the switches, which form a dipole antenna and which are used both for the high-frequency antenna current conduction and for feeding the switches. The antenna is provided at its central feed point with a control circuit for the frequency tuning. Each switch is formed by a bistable relay with an associated drive circuit which no longer requires power after switching, the disconnected antenna sections with the switches associated thereto being electrically isolated from the remaining part of the antenna after completion of the length matching. The control circuit is so desinged that, in each frequency interval corresponding to a particular antenna length, an impedance matching at a freely selectable number of tuning frequencies is achieved with the aid of a circuit containing reactances.

Dependencies are inferred from the claim text.