Abstract: An antenna system enabling a link between an airborne object sending out a signal E with any polarization and a moving body equipped with a dual-polarization antenna comprises at least one device to determine the position of the moving body and of the airborne object, and an assembly for positioning the antenna. The system comprises at least one polarization combiner receiving two signals H and V coming from the dual-polarization antenna, the signals H and V resulting from the signal coming from the airborne object; the combiner being adapted to recombining the signals H and V in order to obtain a signal E optimizing the link balance between the moving body and the airborne object.

Abstract: An antenna comprises one or more radiating strands where at least one radiating strand has both its ends connected by means of one or more conductive wires, the radiating strands forming part of the upper pole of the antenna. Application to monopole or dipole type antennas working in the frequency ranges corresponding to the HF, VHF or UHV bands.

Abstract: An antenna comprises one or more radiating strands where at least one radiating strand has both its ends connected by means of one or more conductive wires, the radiating strands forming part of the upper pole of the antenna. Application to monopole or dipole type antennas working in the frequency ranges corresponding to the HF, VHF or UHV bands.

Abstract: The power loads in certain applications such as dummy antennas must have a substantially constant impedance in a wide band of frequencies. The power load is air-cooled and its resistive element is constituted by the series-connection of resistor modules made of expanded metal. Capacitors are positioned in a branching connection on the resistive element. The positioning of the capacitors along the resistive element and their value are determined to ensure frequency compensation.

Abstract: Switchable inductors for strong currents are used especially in antenna tuning circuits. The value of the inductance between the terminals of the primary winding of an air-core static transformer is different depending on whether the secondary winding of the transformer is placed in an open circuit or in a short circuit by switching means formed by power semiconductor elements. Application in particular to antenna coupling circuits for VLF stations working by frequency hop transmission with highly selective antennas.