Centre National Detudes Spatiales

Centre National De La Recherche Scientifique

Alcatel Thomson Espace

Hubert Diez

Hervé Aubert

Alexandru Takacs

Daniel Renaud

Daniel Belot

Gilles Duret

Julia Lemaitre

Philippe Raizonville

The invention concerns a helical antenna comprising a shape of revolution and a plurality of radiating strands helically wound around the shape of revolution, characterized in that each radiating strand is defined by a repetition of a fractal pattern comprising segments formed by a sinusoidal curve.

Compact helical antenna with a sinusoidal profile modulating a fractal pattern

The invention discloses a transmission device comprising an antenna having a plurality of aerial wires uniformly distributed regularly in a helix about a cylindrical generatrix, and means for feeding the aerial wires with a radio frequency signal. The invention is characterized in that the means for feeding produces an equi-phase and equi-amplitude signal which directly feeds the plurality of aerial wires.

Transmission device with omnidirectional antenna

An orbiting satellite system with an antenna for re-transmitting to the ground images collected by image capture instruments of the satellite, the antennas having more than one elementary radiating antenna each of which has more than one cord regularly distributed in a helix about a generatrix of revolution and equi-amplitude power supply for the various cords where the axis of the various elementary antenna are parallel and aligned in one and the same plane in which they are spaced regularly apart in that plane. The plane of the antennas is intended to align with, when the satellite is in orbit, the direction perpendicular to the direction of the speed vector of the satellite. The antenna also has a phase shifting power supply which enables the antenna array to carry out electronic steering of the elongate beam generated by the elementary array.

Antenna for orbiting satellite

The antenna comprises a parabolic reflector (1) and a primary source (2). The reflector (1) comprises a first grating of conductor wires (7) and a second grating of conductor wires (8) which are orthogonal to the wires of the first grating, and with both gratings constituting elliptical reflective surfaces. The sizes of the major and minor axes of the ellipses are determined in such a manner that both operating frequencies of the antenna have identical coverge zones on the surface of the globe.

Growing community of inventors

Leguevin, France

Hubert Diez