Abstract: The invention relates to a method comprising: ° milling of a first waveguide substrate element (1a) to provide two waveguide cavities (3, 5a) with respectively a first and a second port (3re, 5re) on a common side of the first substrate element (1a), ° milling of a recess (5b) on a side of a second waveguide substrate element (1b), ° assembling the first and second substrate elements (1a, 1b) so that the waveguide cavities (3, 5a) and the recess (5b) form a continuous waveguide.

Abstract: The aim of the present invention is a sub-reflector of a dual-reflector antenna comprising: a first end having a junction of a first diameter, adapted for coupling to the end of a waveguide, a second end, having a second diameter greater than the first diameter, a convex reflective internal surface placed at the second end having an axis of revolution, an external surface of the same axis, joining the two ends, a dielectric material extending between the first and the second ends and limited by the internal surface and the external surface, In accordance with the invention, the external surface has a convex profile described by a polynomial equation of the sixth degree of the formula: y=ax6+bx5+cx4+dx3+ex2+fx+g where a is not zero.

Abstract: The object of the present invention is a rigid radome for a broadband parabolic antenna. The radome has a roughly circular shape, and is bent along a diameter towards the interior of the antenna, thereby forming two half-disks. The two half-disks form an angle less than or equal to 12° with the plane perpendicular to the antenna's axis. The radome is made up of a sandwich-style multilayer material, comprising two outer layers surrounding at least one central pitted layer, whose pits have a roughly conical shape.

Abstract: The present invention provides an antenna comprising at least two arrays comprising respective pluralities of radiating elements in alignment, disposed in parallel planes, and metal screens interposed between the arrays, the antenna being characterized in that each metal screen comprises a bottom portion facing non-radiating portions of the radiating elements and comprising respective plane sheets disposed in planes parallel to the planes of the arrays, and top portions facing the radiating portions of the radiating elements and comprising panels, each forming an angle with the planes of the bottom portions. Preferably, each panel is oriented in alternation in one direction and in another direction on either side of the plane of the bottom portion. Advantageously, each panel comprises two wings connected to a central zone attached to the bottom portion of the screen.

Abstract: The present invention relates to a method of assembling a radiocommunication antenna comprising a reflector connected to a subreflector via a circular section waveguide extending along a longitudinal axis. According to the invention, such a method comprises the following steps: the step of pivoting the waveguide about its longitudinal axis to determine a position such that an offset of the plane of propagation of a polarized electromagnetic field transmitted by this guide is limited, the step of marking this position on the waveguide, and the step of fitting the waveguide to the reflector as a function of this mark.

Abstract: The present invention consists in an antenna including at least two arrays of radiating elements disposed linearly and parallel, plane metal screens being interleaved between the arrays. According to the invention screening means, added above the radiating elements, comprise criss-cross metal filaments forming a grid and adapted always to be placed between two radiating elements.

Abstract: The aim of the present invention is a sub-reflector of a dual-reflector antenna comprising: a first end having a junction of a first diameter, adapted for coupling to the end of a waveguide, a second end, having a second diameter greater than the first diameter, a convex reflective internal surface placed at the second end having an axis of revolution, an external surface of the same axis, joining the two ends, a dielectric material extending between the first and the second ends and limited by the internal surface and the external surface, In accordance with the invention, the external surface has a convex profile described by a polynomial equation of the sixth degree of the formula: y=ax6+bx5+cx4+dx3+ex2+fx+g where a is not zero.

Abstract: The antenna feed device (4) of the invention comprises a reflector (2) into which a circular or rectangular section waveguide (8) opens out, the waveguide including a cylindrical or conical radiating aperture (10, 9) at its end. A lens (22) of dielectric material is inserted in part into the inside of the aperture, the portion (23) of the lens (22) projecting out from the waveguide (8) being substantially in the form of a truncated cone and having its smaller diameter end (24) facing outwards. The end (24) includes a central cavity (25) of shape that is given by the solution to a polynomial equation of the “b+ax+cx2+dx3” type, or to a logarithmic equation.

Abstract: The present invention provides an antenna comprising at least two arrays comprising respective pluralities of radiating elements in alignment, disposed in parallel planes, and metal screens interposed between the arrays, the antenna being characterized in that each metal screen comprises a bottom portion facing non-radiating portions of the radiating elements and comprising respective plane sheets disposed in planes parallel to the planes of the arrays, and top portions facing the radiating portions of the radiating elements and comprising panels, each forming an angle with the planes of the bottom portions. Preferably, each panel is oriented in alternation in one direction and in another direction on either side of the plane of the bottom portion. Advantageously, each panel comprises two wings connected to a central zone attached to the bottom portion of the screen.

Abstract: The present invention consists in an antenna including at least two arrays of radiating elements disposed linearly and parallel, plane metal screens being interleaved between the arrays. According to the invention screening means, added above the radiating elements, comprise crisscross metal filaments forming a grid and adapted always to be placed between two radiating elements.

Abstract: The present invention relates to a method of assembling a radiocommunication antenna comprising a reflector connected to a subreflector via a circular section waveguide extending along a longitudinal axis. According to the invention, such a method comprises the following steps: the step of pivoting the waveguide about its longitudinal axis to determine a position such that an offset of the plane of propagation of a polarized electromagnetic field transmitted by this guide is limited, the step of marking this position on the waveguide, and the step of fitting the waveguide to the reflector as a function of this mark.

Abstract: An antenna feed comprises, aligned and centered on an axis OO?, a waveguide having an inside diameter, a first end and a second end, a dielectric body having a portion inside the waveguide and a portion outside the waveguide, the outside portion comprising a section of frustoconical shape having an outside lateral surface of frustoconical shape with two ends, namely a large diameter end and a small diameter end, and a subreflector at the large diameter end of the frustoconical shape. The outside portion comprises, in addition to the frustoconical portion, a cylindrical portion whose diameter is greater than the inside diameter of the waveguide. The cylindrical portion is connected to the frustoconical portion at its small diameter end and the frustoconical outside lateral surface of the dielectric body is smooth.

Abstract: The invention concerns the secondary reflectors of SHF antennae of the Cassegrain type. It consists of providing the secondary basic reflector (103) of this antenna with a first circular ring (104) in the shape of a cylinder directed toward the main reflector, and a second ring (105) in the shape of a circular crown fixed to the end of the cylinder, and projecting outward from the latter. These rings are made from a conducting material. The length of the cylinder and the width of the crown are of the range of one quarter of the average wavelength for which the antenna is dimensioned. This enables the “overspill radiation” of the secondary reflector to be reduced considerably, and therefore allows the dimensions of the antenna to be reduced significantly for equivalent performance.

Abstract: The invention concerns the secondary reflectors of SHF antennae of the Cassegrain type.

Abstract: The invention concerns a vertical polarisation antenna comprising dipoles at different levels of an elongated vertical support structure. The invention is characterised in that it comprises only one of said dipoles (1, 2) per level of said structure (3) and said dipoles are coplanar and substantially collinear on said structure, but inverted with respect to one another.