Abstract: A process for manufacturing an optical element comprising a first step of spinning a circular sheet of a first metallic material for it to adhere to a rotating matrix and form a shell; a second step of assembling the shell on a temporary support; and at least a third step of diamond turning the shell by means of a diamond tool to obtain an optical surface.

Abstract: A beamforming network for use with a plurality of antenna elements arranged in a planar array of linear sub-arrays includes first and second sets of beamforming sub-networks. Each beamforming sub-network in the first set of beamforming sub-networks is associated with a respective one of the linear sub-arrays and is adapted to generate, via the associated linear sub-array, fan beams along respective beam directions in a first set of beam directions. Each beamforming sub-network in the second set of beamforming sub-networks is associated with a respective one of the beam directions in the first set of beam directions. For each beamforming sub-network in the second set of beamforming sub-networks, each of the output port is coupled to an input port of a respective beamforming sub-network in the first set of beamforming sub-networks that corresponds to the associated beam direction. The application further relates to a multibeam antenna comprising such beamforming network.

Abstract: A beamforming network for use with a plurality of antenna elements arranged in a planar array of linear sub-arrays includes first and second sets of beamforming sub-networks. Each beamforming sub-network in the first set of beamforming sub-networks is associated with a respective one of the linear sub-arrays and is adapted to generate, via the associated linear sub-array, fan beams along respective beam directions in a first set of beam directions. Each beamforming sub-network in the second set of beamforming sub-networks is associated with a respective one of the beam directions in the first set of beam directions. For each beamforming sub-network in the second set of beamforming sub-networks, each of the output port is coupled to an input port of a respective beamforming sub-network in the first set of beamforming sub-networks that corresponds to the associated beam direction. The application further relates to a multibeam antenna comprising such beamforming network.

Abstract: A directional waveguide coupler (20) has four input ports and four output ports. Each input port is coupled to each of the output ports. The directional coupler (20) includes a first coupler having two waveguides (W1, W2) coupled to each other by a first slot array (S1), defined in a first wall (21) common to the two waveguides (W1, W2) of the first coupler. A second coupler has two waveguides (W3, W4), coupled to each other by a second slot array (S2), defined in a second wall (22) common to the two waveguides (W3, W4) of the second coupler. The first and second slot arrays (S1, S2) lie on a first common plane. The first and second couplers are coupled to each other by a third slot array (S3) and a fourth slot array (S4), which lie on a second common plane perpendicular to the first common plane.

Abstract: A directional waveguide coupler (20) has four input ports and four output ports. Each input port is coupled to each of the output ports. The directional coupler (20) includes a first coupler having two waveguides (W1, W2) coupled to each other by a first slot array (S1), defined in a first wall (21) common to the two waveguides (W1, W2) of the first coupler. A second coupler has two waveguides (W3, W4), coupled to each other by a second slot array (S2), defined in a second wall (22) common to the two waveguides (W3, W4) of the second coupler. The first and second slot arrays (S1, S2) lie on a first common plane. The first and second couplers are coupled to each other by a third slot array (S3) and a fourth slot array (S4), which lie on a second common plane perpendicular to the first common plane.

Abstract: A method of manufacturing an array antenna comprising: a design phase wherein an array layout of said array antenna is synthesized and radiating elements are designed to be arranged according to said array layout; and a phase of physically making said array antenna wherein the radiating elements are arranged according to said array layout.

Abstract: A method for manufacturing an array antenna having a design phase, including synthesizing an array layout of the array antenna and choosing or designing radiating elements to be arranged according to the array layout; and a phase of physically making the array antenna, including arranging the radiating elements according to the array layout; the design phase having the steps of: a) synthesizing an array layout complying with a required minimum beamwidth, a required field of view, a required side lobe level and a target angular dependence of the maximum directivity of the array antenna over the required field of view; b) determining shaped radiation patterns of the radiating elements in order to approximate said target angular dependence of the maximum directivity of the array antenna over the required field of view; and c) choosing or designing radiating elements having the shaped radiation patterns determined at step b).

Abstract: An array antenna has rectangular conductor sections, located successively side by side in a first plane, mutually separated by slots of constant width. A backing reflector is transverse to the first plane. Feed structures extend through the backing reflector, the feed structures comprising pairs of parallel feed conductors, each pair comprising conductors coupled to the rectangular conductor sections on opposite sides of a respective one of the slots.

Abstract: The application discloses a one or two dimensional array of electromagnetic scatterers n scatterers (ED), whereby the aforementioned scatterers (ED) are arranged aperiodically on a curved line or surface (S). Further, the application describes a reflectarray antenna comprising at least one such array of electromagnetic scatters (ED) and at least one receiving and/or transmitting feed (F), cooperating with said array to generate an antenna beam A method for designing and manufacturing sais array and said antenna is explained. The method optimizes in a several stages all degrees of freedom in order improve the performance of reflectarrays, increase the flexibility thereof and/or the conformity thereof with design specifications (radio pattern) and/or allowing said specifications to be satisfied with a smaller number of scatters.

Abstract: A wideband reflectarray antenna for dual polarizations application is formed by an array of phasing cells, where each cell contains two orthogonal or quasi-orthogonal sets of parallel conductive dipoles printed on two levels of a multilayered grounded substrate. The dipoles for each polarization are coupled in both horizontal and vertical directions, providing a large broadband operation and low cross-polarization with only two levels of metallizations. The antenna is designed by adjusting the lengths of the dipoles to produce the phase-shift required to collimate or shape the radiated beam in dual-polarization when illuminated by a feed, either in broadband or dual-frequency operation. The invention also relates to a design and manufacturing method for producing the reflectarray antenna, based on the optimization of the dipole lengths for each phasing cell.

Abstract: An offset imaging antenna system with compensated optical aberrations comprises a main a paraboloid reflector, a first paraboloid sub reflector, and a first feeding array as an arrangement of first feed array elements to illuminate or to be illuminated by the first sub reflector. The main reflector and the first sub reflector are confocal by sharing a common focal point. The first feeding array has a curved shape that corresponds to a first equivalent array of magnified image feed elements lying on a plane crossing the main optical centre and perpendicular to the main bore-sight axis, all the first feed array elements being positioned as to provide a planar distribution of the positions of the image feed elements onto the first equivalent array after a second reflection by the main reflector with a central image point coinciding with the main reflector optical centre under a maximum illumination condition.

Abstract: A beam-forming network for an emitting array antenna having at least NB input ports connected to respective beam ports of the beam-forming network and at least NOSA>1 output ports, for associating to each output port a linear combination of input signals from respective input ports; a set of at least NOSA lossless single-mode networks, each having an input port connected to a respective output port of multi-beam network and at least NNOSAOSA>1 output ports, for associating to each output port a signal obtained by weighting an input signal from the input port; and a set of at least NNOSA?NNOSAOSA lossless multi-mode networks, each having at least NNOSAOSA NOSANOSA input ports, each one connected to an output port of a respective single-mode network, and at least NENOSA>1 output ports connected to respective antenna ports of the beam-forming network, for associating to each output port a linear combination of input signals from respective input ports.

Abstract: A beam-forming network for an emitting array antenna having at least NB input ports connected to respective beam ports of the beam-forming network and at least NOSA>1 output ports, for associating to each output port a linear combination of input signals from respective input ports; a set of at least NOSA lossless single-mode networks, each having an input port connected to a respective output port of multi-beam network and at least NNOSAOSA>1 output ports, for associating to each output port a signal obtained by weighting an input signal from the input port; and a set of at least NNOSA?NNOSAOSA lossless multi-mode networks, each having at least NNOSAOSA NOSANOSA input ports, each one connected to an output port of a respective single-mode network, and at least NENOSA>1 output ports connected to respective antenna ports of the beam-forming network, for associating to each output port a linear combination of input signals from respective input ports.

Abstract: A method of manufacturing an array antenna comprising: a design phase wherein an array layout of said array antenna is synthesized and radiating elements are designed to be arranged according to said array layout; and a phase of physically making said array antenna wherein the radiating elements are arranged according to said array layout.

Abstract: A method for manufacturing an array antenna having a design phase, including synthesizing an array layout of the array antenna and choosing or designing radiating elements to be arranged according to the array layout; and a phase of physically making the array antenna, including arranging the radiating elements according to the array layout; the design phase having the steps of: a) synthesizing an array layout complying with a required minimum beamwidth, a required field of view, a required side lobe level and a target angular dependence of the maximum directivity of the array antenna over the required field of view; b) determining shaped radiation patterns of the radiating elements in order to approximate said target angular dependence of the maximum directivity of the array antenna over the required field of view; and c) choosing or designing radiating elements having the shaped radiation patterns determined at step b).

Abstract: A multibeam antenna comprising: a plurality of primary radiating elements, each associated to a respective beam; and an active radiating structure comprising a first planar array of radiating elements, a second planar array composed by a same number of radiating elements, a set of connections between each radiating element of the first planar array and one corresponding element of the second planar array, and a set of power amplifiers for amplifying signals transmitted through said connections; wherein: the relative positions of the radiating elements of the first and second planar arrays and phase delays introduced by said connections are such that the radiating structure forms an active discrete converging lens; and said primary radiating elements are clustered on a focal surface of said lens, facing the first planar array; characterized in that said first and second planar arrays are both aperiodic. A method of manufacturing such an antenna.

Abstract: The application discloses a one or two dimensional array of electromagnetic scatterers n scatterers (ED), whereby the aforementioned scatterers (ED) are arranged aperiodically on a curved line or surface (S). Further, the application describes a reflectarray antenna comprising at least one such array of electromagnetic scatters (ED) and at least one receiving and/or transmitting feed (F), cooperating with said array to generate an antenna beam A method for designing and manufacturing said array and said antenna is explained. The method optimizes in a several stages all degrees of freedom in order improve the performance of reflectarrays, increase the flexibility thereof and/or the conformity thereof with design specifications (radio pattern) and/or allowing said specifications to be satisfied with a smaller number of scatters.

Abstract: An array antenna with high suppression of cross-polarization has rectangular conductor sections, located successively side by side in a first plane, mutually separated by slots of constant width. A backing reflector transverse to said first plane. Feed structures extend through the backing reflector, the feed structures comprising pairs of parallel feed conductors, each pair comprising conductors coupled to the rectangular conductor sections on opposite sides of a respective one of the slots.

Abstract: A method of manufacturing an array antenna including a designing step which comprises: determining a one-dimensional reference radiation pattern and an associated reference aperture; computing the cumulative phasorial summation of the field distribution of said reference aperture in a reference direction and representing it as a reference curve in the complex plane; determining a polygonal curve optimally approximating said reference curve, subject to predetermined constraints; and determining, from said polygonal curve, an antenna array pattern, each side of said polygonal curve being associated to a particular antenna element of the array.

Abstract: A multibeam antenna comprising: a plurality of primary radiating elements, each associated to a respective beam; and an active radiating structure comprising a first planar array of radiating elements, a second planar array composed by a same number of radiating elements, a set of connections between each radiating element of the first planar array and one corresponding element of the second planar array, and a set of power amplifiers for amplifying signals transmitted through said connections; wherein: the relative positions of the radiating elements of the first and second planar arrays and phase delays introduced by said connections are such that the radiating structure forms an active discrete converging lens; and said primary radiating elements are clustered on a focal surface of said lens, facing the first planar array; characterized in that said first and second planar arrays are both aperiodic. A method of manufacturing such an antenna.