Abstract: The invention relates to a particular structure of high-frequency antenna, which comprises a support element (1) provided with a cylindrical coil conductor which forms a helix (2). On the support element (1) there is formed, for example by means of a conductive coating, the electrical parts of the antenna, such as the attachment points (3b) for the helix and for other parts, such as feeder lines (4), radiators (5) or impedance matching devices. By varying the number and size of the helices (2), the number and form of the feeder lines (4) and radiators (5) and the quality of any impedance matching devices, it is possible without difficulty to obtain a very wide choice of different antenna structures. The feeder lines and radiators extend, at least in part, within the helix.

Abstract: The invention relates to a double-action, two-piece antenna structure whose first antenna part, preferably a helix antenna (1), is fixedly connected to the antenna port of a radio communications set, and the second antenna port, preferably a rod antenna (2), is movable with respect to the first antenna part. In an active position, the second antenna part (2) is coupled to the first antenna part (1), forming a serial connection whose electrical length is as great as or greater than the electrical length of the first antenna part alone.