EP3726642A1 - Polarising screen with wideband polarising radiofrequency cell(s) - Google Patents

Abstract

A polarizing screen comprises an arrangement of at least one polarizing cell (s) (112), electrically conductive (s), selective in frequency and polarization, to transform the polarization of the electrical component E of the TEM electromagnetic wave, received in linear polarization into an electromagnetic wave of circular polarization. The four side walls (124, 125, 126, 127) of each waveguide section (120) forming a polarizing cell (112) are each open along their entire length by a continuous middle slit (134, 135, 136, 137), parallel to the direction of propagation of the incident electromagnetic wave, so as to form four folded electrically conductive plates.Each polarizing cell (112) includes electrically conductive interconnection rods which interconnect the side walls and the four folded plates to make them partially or totally integral and which form one or more electrical discontinuities (152), which are arranged at the ends or inside the waveguide section forming the polarizing cell and carry one or more capacitive (s), inductive (s), or one or more resonators (s) equivalent (s) (L, C) to an inductor and a capacitor connected in parallel or in series The longitudinal open slits of the side walls and the elementary electrical discontinuities of each polarizing cell have geometric shapes and dimensions that achieve a total transmission of the incident wave, associated with a phase anisotropy of + 90 ° or -90 ° depending on the components EV and EH.

Description

The present invention relates to a radiofrequency polarizer screen with high radioelectric performance, produced from an arrangement of one or more polarizing cell (s), made of an electrically conductive material and frequency selective. and in polarization, which makes it possible to transform an incident RF radiofrequency signal, received in linear polarization, into an output RF radiofrequency signal in circular polarization.

The invention also relates to a method of manufacturing a polarizer screen according to the invention.

Each polarizing cell of the polarizing screen according to the invention is produced by a waveguide section, configured to receive as input the incident electric field E of the injected RF signal, which can be broken down into two electric field signals E _V , E _H the polarizations of which are linear and mutually orthogonal along a first direction, denoted V and called by convention “vertical”, and a second direction, orthogonal to the first direction, denoted H and called by convention “horizontal”.

The transformation carried out by each polarizing cell consists in applying a phase shift of + 90 ° or -90 ° between the two components E _V and E _H of the input linear polarization signal E.

The polarizer screen according to the invention is assumed to operate on a single RF frequency band, preferably over a wide bandwidth.

Since the structure of the polarizer screen according to the invention can be entirely metallic, this structure is particularly suitable for new additive manufacturing processes.

The polarizer screen according to the invention is applicable to any thin multi-beam antenna and more particularly to the field of space telecommunications, in particular to antennas intended to be mounted on board aircraft. satellites, or antennas intended for use on the ground on fixed or mobile terminals.

It should be noted that a polarizing screen according to the invention can be used for antennas which do not allow circular polarization signals to be synthesized simply, such as for example the antenna described in the patent. FR 3038457 B1 forming a first document, said antenna radiating from a continuous and elongated opening, using a waveguide beam former with parallel plates, make it possible to form several beams over a wide angular sector.

It is known to produce polarizing screens or 3-D surfaces, selective in frequency and polarization, from polarizing cells formed by waveguide sections, in order to overcome the limitations of RF performance and size of the screens. Multilayer polarizers, selective in frequency and polarization and which use quarter wave multilayer surfaces with dielectric substrates.

A first type of known polarizing screen with waveguide sections is a metallic polarizing screen of the OMT (Orthogonal Mode Transducer) type polarization duplexer, consisting of an array of iris or waveguide waveguides. septum, and described for example in the article by M. Chen and G. Tsandoulas, titled "A wide-band square-wave guide array polarizer", published in IEEE TAP, Vol. 21, No. 3, pp. 389-391, May 1973 , and forming a first document. The OMT septum polarization duplexer described in this first document is a device frequently used in antennas for satellite telecommunications. It usually converts two linear polarized signals, injected into accesses with superimposed waveguides, into two signals with orthogonal circular polarizations thanks to a septum plate whose profile is optimized.

A second type of polarizing screen with waveguide sections is a metallic dichroic polarizing screen, consisting of an array of waveguides with slit resonators.

The article of T. Wang, J. Zhu, C. Wang, J. Ge and Z. Yu, titled “Wave 3-D FSSs by 3-D printing technique”, published in International Conférence on Electromagnetics in Advance Applications (ICEAA) 2016, Caims (Australia), November 2016 and forming a second document, describes a first embodiment of the second type of polarizer screen as a periodic arrangement of polarizing cells, formed of guided sections under cut-off, ie allowing propagation of a guided mode only beyond the cut-off frequency which is lower than the desired operating frequency, and on the vertical and horizontal walls of which folded resonant slots without loops have been inserted. At the resonant frequency of the slits, the guided sections transmit the radio signal. The parameters of the slits of each polarizing cell are adjusted so as to obtain a total transmission on the two components (E _V , E _H ) of the incident electrical signal E in linear polarization E, as well as a phase shift of between the two components E _V and E _H.

The article of C. Molero, T. Debogovic and M. Garcia-Vigueras, titled “Design of full-metal polarizing screen based on circuit modeling”, published in International Microwave Symposium (IMS), Philadelphia, USA, 2018 and forming a third document, describes a second embodiment of the second type of polarizing screen as a periodic arrangement of polarizing cells, formed of guided sections under cut-off, ie allowing propagation of a guided mode only beyond the cut-off frequency which is lower than the desired operating frequency, and of metal plates, placed at the input and at the outputs of the guided sections, and on which two pairs of folded resonant slots without loops have been inserted. Each pair of slots resonates according to an Ex or Ey polarization. This results in transmission in a frequency band, and it is possible to adjust the anisotropy of the polarizing cells through the design of the slit resonators in terms of shapes and dimensions, so that a phase shift of + 90 ° or -90 ° is obtained between the two coefficients in transmission acting on the two components (Ex, Ey) of the incident signal in linear polarization E.

According to a third embodiment of the second type of polarizer screen, it is also possible to combine the two techniques, used for the first and second embodiments of the second type of screen, and described above.

All first type or second type waveguide section polarizer screen structures are metallic and easier to manufacture.

However, these structures have a narrow pass band, and if resonators are added to the walls of the guided sections to widen the band, the polarizing cells obtained then have a significant thickness compared to the wavelength of the electromagnetic signal, which confers at the polarizer screen, a high and unwanted sensitivity to the angle of incidence of the signal injected at the input.

The technical problem is to increase the bandwidth of a polarizer screen whose polarizing cell (s) are waveguide sections, each having two pairs of side walls parallel to each other electrically conductive, without widening the thickness. of said side walls.

To this end, the invention relates to a polarizer screen, comprising an arrangement of at least one polarizing cell (s), made of an electrically conductive material, selective in frequency and polarization. , to transform the linear polarization of the electric field E of an incident electromagnetic wave TEM, received at the input and decomposable into two electric field signals E _V , E _H whose vertical and horizontal polarizations are linear and orthogonal, into a circular polarization d 'an output electric field, and in which each polarizing cell has a waveguide section having two orthogonal, vertical and horizontal pairs of side walls parallel to each other and extended longitudinally along a direction of propagation of a incident EMT electromagnetic wave.

The polarizer screen is characterized in that the four side walls of each polarizing cell are each open over their entire length by a continuous median slot, parallel to the direction of propagation of the incident electromagnetic wave, so as to form four folded plates electrically conductive; and each polarizing cell includes electrically conductive rods which interconnect the side walls and the four folded plates to make them partially or completely integral and which form one or more successive elementary electrical discontinuities, which are arranged at the end or inside the guide section wave forming the polarizing cell and produce one or more capacitive (s), inductive (s), or one or more resonator (s) equivalent (L, C) to an inductor and a connected capacitor in parallel or in series; and the longitudinally open slits of the side walls and the elementary electrical discontinuities of each polarizing cell comprise geometric shapes and dimensions which achieve total transmission of the incident wave, associated with a phase anisotropy of + 90 ° or -90 ° depending on the components E _V and E _H.

• les sections de guide d'onde et les tiges d'interconnexion, formant chaque cellule polarisante, électriquement conductrices sont constituées par un unique matériau homogène électriquement conducteur, ou un premier matériau recouvert par un deuxième matériau électriquement conducteur ;
• l'unique matériau homogène électriquement conducteur est un métal, ou le deuxième matériau électriquement conducteur est un métal ;
• les fentes continues médianes des quatre murs latéraux de chaque section de guide d'onde formant une cellule polarisante, sont échancrées en entrée et en sortie de la section du guide d'onde ; ou les fentes continues médianes d'une seule paire de murs latéraux parallèles de chaque section de guide d'onde formant une cellule polarisante, sont échancrées en entrée et en sortie de la section du guide d'onde ; ou les fentes continues médianes des quatre murs latéraux de chaque section de guide d'onde formant une cellule polarisante, sont dépourvues d'échancrure en entrée et en sortie de la section du guide d'onde ;
• les cellules polarisantes sont dimensionnées pour fonctionner dans une bande de fréquence comprise dans l'une des bandes L, S, C, Ku et Ka ;
• chaque cellule polarisante inclut des tiges pleines en matériau électriquement conducteur, d'interconnexion des murs latéraux en une interconnexion en forme de H, réalisant une unique discontinuité électrique élémentaire ; et l'interconnexion en forme de H formant la discontinuité électrique élémentaire, disposée à l'intérieur de section de guide d'onde et sensiblement au milieu de la longueur de la cellule polarisante, est constituée de deux premières tiges verticales de même longueur et d'une deuxième tige horizontale reliant sensiblement en leur milieu lesdites deux tiges verticales, les deux premières tiges verticales connectant une paire de murs latéraux horizontaux, inférieur et supérieur, de sorte à réaliser un premier circuit résonateur L_V, C_V parallèle pour une première polarisation verticale, et un deuxième circuit résonateur L_H, C_H parallèle pour une deuxième polarisation horizontale, orthogonale à la première polarisation verticale ;
• chaque cellule polarisante inclut des tiges en matériau électriquement conducteur, d'interconnexion en forme de X des murs latéraux réalisant une unique discontinuité électrique élémentaire ; et l'interconnexion en forme de X réalisant l'unique discontinuité électrique élémentaire, disposée à l'intérieur de section de guide d'onde sensiblement au milieu de la longueur de la cellule polarisante et symétriquement par rapport à un plan médian longitudinal traversant la section de guide d'onde, est constituée de deux tiges de même longueur, inclinées par rapport à une direction verticale en sens opposé, qui se croisent sensiblement en leur milieu respectif en étant reliées ou faiblement distante au niveau de leur milieu, et qui connectent une paire de murs latéraux horizontaux, inférieur et supérieur, de sorte à réaliser un premier circuit résonateur L_V, C_V parallèle pour une première polarisation verticale, et un deuxième circuit résonateur L_H, C_H parallèle pour une deuxième polarisation horizontale, orthogonale à la première polarisation verticale ;
• chaque cellule polarisante inclut des tiges en matériau électriquement conducteur, d'interconnexion des murs latéraux, en deux interconnexions, formées chacune par deux tiges verticales ou poteaux verticaux sans connexion centrale entre eux, et réalisant chacune une interconnexion électrique élémentaire ; et les deux interconnexions, première et deuxième, réalisant les deux discontinuités électriques élémentaires, disposées à l'intérieur de la section de guide d'onde formant la cellule polarisante et en retrait des extrémités respectives d'entrée et de sortie de ladite section de guide d'onde, connectent les deux murs latéraux horizontaux, inférieur et supérieur, de sorte à réaliser une charge inductive pour la première polarisation verticale, parallèle à la direction des tiges verticales, et une charge capacitive pour la deuxième polarisation horizontale, orthogonale à la première polarisation verticale ;
• chaque cellule polarisante inclut des tiges en un matériau électriquement conducteur, d'interconnexion des murs latéraux suivant deux interconnexions successives en forme de H, réalisant deux discontinuités électriques élémentaires ; et les deux interconnexions successives, première et deuxième, réalisant les deux discontinuités élémentaires, disposées à l'intérieur de la section de guide d'onde formant la cellule polarisante et en retrait des extrémités respectives d'entrée et de sortie de ladite section de guide d'onde, sont constituées chacune de deux premières tiges verticales de même longueur et d'une deuxième tige horizontale reliant sensiblement en leur milieu lesdites deux tiges verticales, les deux premières tiges verticales connectant les murs latéraux horizontaux, inférieur et supérieur, de sorte à réaliser chacun un premier circuit résonateur L_V, C_V parallèle pour la première polarisation verticale, et un deuxième circuit résonateur L_H, C_H parallèle pour la deuxième polarisation horizontale, orthogonale à la première polarisation verticale ;
• chaque cellule polarisante inclut des tiges en matériau électriquement conducteur, d'interconnexion des murs latéraux suivant deux interconnexion en forme de X, réalisant deux discontinuités électriques élémentaires ; et les deux interconnexions successives, première et deuxième, réalisant les deux discontinuités élémentaires, disposées à l'intérieur de la section de guide d'onde formant la cellule polarisante et en retrait des extrémités respectives d'entrée et de sortie de ladite section de guide d'onde et symétriquement par rapport à un plan médian vertical traversant longitudinalement la section de guide d'onde, sont constituées chacune de deux tiges de même longueur, inclinées par rapport à une direction verticale en sens opposé, qui se croisent sensiblement en leur milieu respectif en étant reliées ou faiblement distantes au niveau de leur milieu, et qui connectent les deux murs latéraux horizontaux, inférieur et supérieur, de sorte à réaliser chacune un premier circuit résonateur L_V, C_V parallèle pour la première polarisation verticale, et un deuxième circuit résonateur L_H, C_H parallèle pour la deuxième polarisation horizontale, orthogonale à la première polarisation verticale ;
• chaque cellule polarisante inclut des tiges en matériau électriquement conducteur, d'interconnexion des murs latéraux suivant deux interconnexions, première et deuxième, en forme de H d'un premier type, réalisant deux discontinuités électriques élémentaires d'un premier type et suivant une interconnexion, troisième, en forme de H d'un deuxième type, réalisant une discontinuité électrique élémentaire d'un deuxième type ; et les deux interconnexions en forme de H de premier type, première et deuxième, disposées à l'intérieur de la section de guide d'onde formant la cellule polarisante et en retrait des extrémités respectives d'entrée et de sortie de ladite section de guide d'onde, sont constituées chacune de deux premières tiges verticales de même longueur et d'une deuxième tige horizontale reliant sensiblement en leur milieu lesdites deux tiges verticales, les deux premières tiges verticales connectant les deux murs latéraux horizontaux, inférieur et supérieur, de sorte à réaliser chacune un premier circuit résonateur L_V1, C_V1 parallèle de premier type pour une première polarisation verticale, et un deuxième circuit résonateur L_H1, C_H1 parallèle pour une deuxième polarisation horizontale, orthogonale à la première polarisation verticale ; et l'interconnexion en forme de H de deuxième type, troisième, disposée à l'intérieur de section de guide d'onde et sensiblement au milieu de la longueur de la cellule polarisante, est constituée de deux troisièmes tiges horizontales de même longueur et d'une quatrième tige verticale reliant sensiblement en leur milieu lesdites deux troisièmes tiges horizontales, les deux troisièmes tiges horizontales connectant les murs latéraux verticaux, gauche et droit, de sorte à réaliser un premier circuit résonateur L_V2, C_V2 parallèle de deuxième type pour la première polarisation verticale, et un deuxième circuit résonateur L_H2, C_H2 parallèle de deuxième type pour la deuxième polarisation horizontale ;
• l'écran polariseur comporte une structure de support latéral qui enveloppe latéralement l'agencement les cellules polarisantes et sur laquelle sont fixées des extrémités de tiges rendant solidaires partiellement ou en totalité chaque cellule polarisante ; ou deux plaques parallèles de guidage et d'injection (706) du signal électrique incident, polarisées linéairement, fixées en bout de murs de cellules polarisant de sorte à rendre solidaires les cellules polarisantes de l'écran polariseur en coopération avec des tiges d'interconnexion solidarisant des groupes de cellules polarisantes ;
• l'agencement des cellules polarisantes est un agencement bidimensionnel continu d'au moins trois cellules polarisantes (512) ajustées sur une surface régulière.

According to particular embodiments, the polarizer screen comprises one or more of the following characteristics, taken individually or in combination:

• the waveguide sections and the interconnection rods, forming each polarizing cell, electrically conductive, consist of a single homogeneous electrically conductive material, or a first material covered by a second electrically conductive material;
• the only homogeneous electrically conductive material is a metal, or the second electrically conductive material is a metal;
• the median continuous slits of the four side walls of each waveguide section forming a polarizing cell, are notched at the input and at the output of the waveguide section; or the median continuous slits of a single pair of parallel side walls of each waveguide section forming a polarizing cell, are notched at the entry and exit of the waveguide section; or the median continuous slits of the four side walls of each waveguide section forming a polarizing cell, are devoid of notches at the entry and exit of the waveguide section;
• the polarizing cells are sized to operate in a frequency band included in one of the bands L, S, C, Ku and Ka;
• each polarizing cell includes solid rods of electrically conductive material, interconnecting the side walls in an H-shaped interconnection, achieving a single elementary electrical discontinuity; and the H-shaped interconnection forming the elementary electrical discontinuity, disposed within the waveguide section and substantially in the middle of the length of the polarizing cell, consists of two first rods verticals of the same length and a second horizontal rod connecting substantially in their middle said two vertical rods, the first two vertical rods connecting a pair of horizontal, lower and upper side walls, so as to produce a first resonator circuit L _V , C _V parallel for a first vertical polarization, and a second resonator circuit L _H , C _H parallel for a second horizontal polarization, orthogonal to the first vertical polarization;
• each polarizing cell includes rods of electrically conductive material, X-shaped interconnection of the side walls forming a single elementary electrical discontinuity; and the X-shaped interconnection providing the single elementary electrical discontinuity, disposed inside the waveguide section substantially in the middle of the length of the polarizing cell and symmetrically with respect to a longitudinal midplane crossing the section waveguide, consists of two rods of the same length, inclined relative to a vertical direction in the opposite direction, which intersect substantially in their respective middle while being connected or slightly distant at their middle, and which connect a pair of horizontal side walls, lower and upper, so as to produce a first resonator circuit L _V , C _V parallel for a first vertical polarization, and a second resonator circuit L _H , C _H parallel for a second horizontal polarization, orthogonal to the first vertical polarization;
• each polarizing cell includes rods of electrically conductive material, interconnecting the side walls, in two interconnections, each formed by two vertical rods or vertical posts without central connection between them, and each making an elementary electrical interconnection; and the two interconnections, first and second, making the two elementary electrical discontinuities, arranged inside the waveguide section forming the polarizing cell and set back from the respective inlet and outlet ends of said guide section wave, connect the two horizontal side walls, lower and upper, so as to realize an inductive load for the first vertical polarization, parallel to the direction of the vertical rods, and a capacitive load for the second horizontal polarization, orthogonal to the first vertical polarization;
• each polarizing cell includes rods made of an electrically conductive material, interconnecting the side walls along two successive H-shaped interconnections, making two elementary electrical discontinuities; and the two successive interconnections, first and second, making the two elementary discontinuities, arranged inside the waveguide section forming the polarizing cell and set back from the respective inlet and outlet ends of said guide section wave, each consist of two first vertical rods of the same length and a second horizontal rod connecting substantially in their middle said two vertical rods, the first two vertical rods connecting the horizontal side walls, lower and upper, so as to each perform a first resonator circuit L _V , C _V parallel for the first vertical polarization, and a second resonator circuit L _H , C _H parallel for the second horizontal polarization, orthogonal to the first vertical polarization;
• each polarizing cell includes rods of electrically conductive material, interconnecting the side walls along two X-shaped interconnections, making two elementary electrical discontinuities; and the two successive interconnections, first and second, making the two elementary discontinuities, arranged inside the waveguide section forming the polarizing cell and set back from the respective inlet and outlet ends of said guide section wave and symmetrically with respect to a vertical median plane longitudinally crossing the waveguide section, each consist of two rods of the same length, inclined with respect to a vertical direction in the opposite direction, which intersect substantially in their middle respective by being connected or slightly distant at the level of their middle, and which connect the two horizontal side walls, lower and upper, so as to each produce a first resonator circuit L _V , C _V parallel for the first vertical polarization, and a second parallel resonator circuit L _H , C _H for the second horizontal polarization, orthogonal to the first vertical polarization;
• each polarizing cell includes rods of electrically conductive material, interconnecting the side walls along two interconnections, first and second, in the shape of an H of a first type, making two elementary electrical discontinuities of a first type and following a third H-shaped interconnection of a second type, forming an elementary electrical discontinuity of a second type; and the two H-shaped interconnects of the first type, first and second, disposed inside the waveguide section forming the polarizing cell and recessed from the respective inlet and outlet ends of said guide section wave, each consist of two first vertical rods of the same length and of a second horizontal rod connecting substantially in their middle said two vertical rods, the first two vertical rods connecting the two horizontal side walls, lower and upper, so in each making a first parallel resonator circuit L _V1 , C _V1 of the first type for a first vertical polarization, and a second resonator circuit L _H1 , C _H1 parallel for a second horizontal polarization, orthogonal to the first vertical polarization; and the second, third type H-shaped interconnection disposed within the waveguide section and substantially in the middle of the length of the polarizing cell, consists of two third horizontal rods of the same length and d 'a fourth vertical rod connecting substantially in their middle said two third horizontal rods, the two third horizontal rods connecting the vertical side walls, left and right, so as to produce a first parallel resonator circuit L _V2 , C _V2 of the second type for the first vertical polarization, and a second parallel resonator circuit L _H2 , C _H2 of the second type for the second horizontal polarization;
• the polarizer screen comprises a lateral support structure which laterally surrounds the arrangement of the polarizing cells and on which are fixed the ends of rods making each polarizing cell partially or totally integral; or two parallel plates for guiding and injecting (706) the incident electrical signal, linearly polarized, fixed at the end of polarizing cell walls so as to make the polarizing cells of the polarizing screen integral with cooperation with interconnection rods uniting groups of polarizing cells;
• the polarizing cell arrangement is a continuous two-dimensional arrangement of at least three polarizing cells (512) fitted to a regular surface.

A subject of the invention is also a method of manufacturing a polarizing screen as defined above and the manufacturing method is characterized in that the polarizing screen is entirely metallic, and the manufacturing method uses a technique of 3d printing.

• [Fig. 1A] et [Fig. 1B] représentent respectivement une vue générale de la section de guide d'onde utilisée dans une cellule polarisante d'un écran polariseur selon l'invention et de sa représentation électrique par un ligne de transmission d'impédance caractéristique variable ;
• [Fig. 2A] et [Fig. 2C] représentent les vues, sous deux angles de vue d'orientations différentes, correspondant respectivement à une polarisation verticale V et une polarisation horizontale H d'une onde électromagnétique incidente de polarisation linéaire, d'un même premier mode de réalisation d'une cellule polarisante d'un écran polariseur selon l'invention comportant une section de guide d'onde dont les quatre murs latéraux sont ouverts chacun longitudinalement sur toute la longueur de la section par une fente continue médiane et une unique discontinuité électrique, réalisée par une interconnexion en forme de H de tiges, électriquement conductrices et interconnectant les murs latéraux, et les
• [Fig. 2B] et [Fig. 2D] représentent les vues des représentations électriques de la cellule polarisante par une première ligne de transmission pour la polarisation verticale V et par une deuxième ligne de transmission pour la polarisation horizontale H ;
• [Fig. 3] représente une vue d'un deuxième mode de réalisation d'une cellule polarisante d'un écran polariseur selon l'invention comportant une section de guide d'onde dont les quatre murs latéraux sont ouverts chacun longitudinalement sur toute la longueur de la section par une fente continue médiane et une unique discontinuité électrique, réalisée par une interconnexion en forme de X de tiges électriquement conductrices ;
• [Fig. 4A] représente une vue d'un troisième mode de réalisation d'une cellule polarisante d'un écran polariseur selon l'invention comportant une section de guide d'onde dont les quatre murs latéraux sont ouverts chacun longitudinalement sur toute la longueur de la section par une fente continue médiane et deux discontinuités électriques, réalisées chacune par une interconnexion de deux tiges verticales, non reliée entre elles, étendues dans la direction de la polarisation verticale et interconnectant les deux murs latéraux horizontales, et les
• [Fig. 4B] et [Fig. 4C] représentent les vues des représentations électriques de la cellule polarisante, correspondantes à la polarisation verticale V et à la polarisation horizontale H, respectivement par une première ligne de transmission et par une deuxième ligne de transmission ;
• [Fig. 5A] représente une vue d'un quatrième mode de réalisation d'une cellule polarisante d'un écran polariseur selon l'invention comportant une section de guide d'onde dont les quatre murs latéraux sont ouverts chacun longitudinalement sur toute la longueur de la section par une fente continue médiane et deux discontinuités électriques, réalisées chacune par une interconnexion en forme de H de tiges interconnectant les murs latéraux, et les
• [Fig. 5B] et [Fig. 5C] représentent les vues des représentations électriques de la cellule polarisante, correspondantes à la polarisation verticale et à la polarisation horizontale, respectivement par une première ligne de transmission et par une deuxième ligne de transmission ;
• [Fig. 6] représente une vue d'un cinquième mode de réalisation d'une cellule polarisante d'un écran polariseur selon l'invention comportant une section de guide d'onde dont les quatre murs latéraux sont ouverts chacun longitudinalement sur toute la longueur de la section par une fente continue médiane et deux discontinuités électriques successives, réalisées chacune par une interconnexion en forme de X de tiges interconnectant les murs latéraux ;
• [Fig. 7A] représente une vue d'un sixième mode de réalisation d'une cellule polarisante d'un écran polariseur selon l'invention comportant une section de guide d'onde dont les quatre murs latéraux sont ouverts chacun longitudinalement sur toute la longueur de la section par une fente continue médiane, deux discontinuités électriques de premier type, réalisées par deux interconnexions successives en forme de H vertical de tiges interconnectant les murs latéraux, et une discontinuité électrique de deuxième type, réalisée par une interconnexion en forme de H horizontal de tiges interconnectant les murs latéraux, et les
• [Fig. 7B] et [Fig. 7C] représentent les vues des représentations électriques de la cellule polarisante, correspondantes à la polarisation verticale V et à la polarisation horizontale H, respectivement par une première ligne de transmission et par une deuxième ligne de transmission ;
• [Fig. 8] représente une vue d'un deuxième mode de réalisation, bidimensionnel, d'un écran polariseur réalisé par un agencement bidimensionnel continu et périodique, de cellules polarisantes, ajustées sur un plan et dont la structure est identique à celle de la cellule polarisante de la Figure 7A;
• [Fig. 9A], [Fig. 9B] et [Fig. 9C] représentent des vues des performances radioélectriques d'un écran polariseur bidimensionnel plan ayant des cellules polarisantes identiques à celle de la Figure 4A, respectivement les courbes d'évolution des paramètres S₁₁, S₂₁ en fonction de la fréquence qui mettent en évidence l'adaptation pour une large bande de fréquence Ka pour les deux composantes électriques E_V et E_H de l'onde électromagnétique incidente, la différence de phase entre les deux coefficients de transmissions S₂₁ pour les deux composantes électriques E_V et E_H de l'onde électromagnétique incidente, et l'évolution du taux d'ellipticité en fonction de la fréquence sur une large bande de bande Ka ;
• [Fig. 10A] et [Fig. 10B] représentent respectivement une vue latérale et une vue en perspective d'un troisième mode de réalisation, bidimensionnel, d'un écran polariseur plan, connecté en entrée à une section de guide d'onde d'injection de l'onde électromagnétique incidence, dans lequel chaque cellule polarisante a la même structure que celle de la cellule de polarisation de la Figure 4A, et comportant une structure de support latéral qui enveloppe l'agencement des cellules polarisantes et fixe les positions de tiges de discontinuités électriques en rendant complètement solidaires les cellules polarisantes ;
• [Fig. 11] représente une vue en en perspective d'un quatrième mode de réalisation, bidimensionnel, d'un écran polariseur plan, connecté en entrée, dépourvu de structure de support latéral, dans lequel chaque cellule polarisante a la même structure que celle de la cellule polarisante de la Figure 4A, et comportant deux plaques parallèles de guidage et d'injection du signal RF d'entrée, connecté en entrée et en bout à des murs latéraux de cellules polarisantes ;
• [Fig. 12A] représente une vue en perspective d'une antenne multifaisceaux dans laquelle est intégré en sortie un écran polariseur à plusieurs cellules polarisantes, similaire à celui décrit dans les Figures 10A-10B, et la
• [Fig. 12B] représente une vue agrandie de la section longitudinale de l'écran polariseur, connecté en sortie de l'antenne multifaisceaux à une section de guide d'onde d'injection du signal électrique incident polarisé linéairement.

The invention will be better understood on reading the description of several embodiments which follows, given solely by way of example and made with reference to the drawings in which:

• [ Fig. 1A] and [Fig. 1B ] respectively represent a general view of the waveguide section used in a polarizing cell of a polarizer screen according to the invention and of its electrical representation by a transmission line of variable characteristic impedance;
• [ Fig. 2A ] and [ Fig. 2C ] represent the views, from two viewing angles of different orientations, corresponding respectively to a vertical polarization V and a horizontal polarization H of an incident electromagnetic wave of linear polarization, of the same first embodiment of a polarizing cell of a polarizer screen according to the invention comprising a waveguide section, the four side walls of which are each open longitudinally over the entire length of the section by a median continuous slot and a single electrical discontinuity, produced by a shaped interconnection of H of rods, electrically conductive and interconnecting the side walls, and the
• [ Fig. 2B ] and [ Fig. 2D ] represent the views of the electrical representations of the polarizing cell by a first transmission line for the vertical polarization V and by a second transmission line for the horizontal polarization H;
• [ Fig. 3 ] shows a view of a second embodiment of a polarizing cell of a polarizing screen according to the invention comprising a waveguide section, the four side walls of which are each open longitudinally over the entire length of the section by a continuous lunge median and a single electrical discontinuity, produced by an X-shaped interconnection of electrically conductive rods;
• [ Fig. 4A ] shows a view of a third embodiment of a polarizing cell of a polarizing screen according to the invention comprising a waveguide section, the four side walls of which are each open longitudinally over the entire length of the section by a central continuous slot and two electrical discontinuities, each made by an interconnection of two vertical rods, not connected to each other, extended in the direction of vertical polarization and interconnecting the two horizontal side walls, and the
• [ Fig. 4B] and [Fig. 4C ] represent the views of the electrical representations of the polarizing cell, corresponding to the vertical polarization V and to the horizontal polarization H, respectively by a first transmission line and by a second transmission line;
• [ Fig. 5A ] shows a view of a fourth embodiment of a polarizing cell of a polarizing screen according to the invention comprising a waveguide section, the four side walls of which are each open longitudinally over the entire length of the section by a continuous middle slot and two electrical discontinuities, each made by an H-shaped interconnection of rods interconnecting the side walls, and the
• [ Fig. 5B] and [Fig. 5C ] represent the views of the electrical representations of the polarizing cell, corresponding to the vertical polarization and to the horizontal polarization, respectively by a first transmission line and by a second transmission line;
• [ Fig. 6 ] shows a view of a fifth embodiment of a polarizing cell of a polarizing screen according to the invention comprising a waveguide section, the four side walls of which are each open longitudinally over the entire length of the section by a central continuous slot and two successive electrical discontinuities, each made by an X-shaped interconnection of rods interconnecting the side walls;
• [ Fig. 7A ] shows a view of a sixth embodiment of a polarizing cell of a polarizing screen according to the invention comprising a section of waveguide whose four side walls are each open longitudinally over the entire length of the section by a continuous median slot, two electrical discontinuities of the first type, produced by two successive vertical H-shaped interconnections of rods interconnecting the side walls, and a second type electrical discontinuity, achieved by a horizontal H-shaped interconnection of rods interconnecting the side walls, and the
• [ Fig. 7B] and [Fig. 7C ] represent the views of the electrical representations of the polarizing cell, corresponding to the vertical polarization V and to the horizontal polarization H, respectively by a first transmission line and by a second transmission line;
• [ Fig. 8 ] represents a view of a second, two-dimensional embodiment of a polarizing screen produced by a continuous and periodic two-dimensional arrangement of polarizing cells, adjusted on a plane and whose structure is identical to that of the polarizing cell of the Figure 7A ;
• [ Fig. 9A ], [ Fig. 9B] and [Fig. 9C ] represent views of the radio performance of a two-dimensional plane polarizer screen having polarizing cells identical to that of the Figure 4A , respectively the evolution curves of the parameters S ₁₁ , S ₂₁ as a function of the frequency which show the adaptation for a wide frequency band Ka for the two electrical components E _V and E _H of the incident electromagnetic wave, the phase difference between the two transmission coefficients S ₂₁ for the two electrical components E _V and E _H of the incident electromagnetic wave, and the evolution of the ellipticity rate as a function of the frequency over a wide band of Ka band ;
• [ Fig. 10A ] and [ Fig. 10B ] respectively show a side view and a perspective view of a third, two-dimensional embodiment of a plane polarizer screen, connected at the input to a waveguide section for injecting the incidence electromagnetic wave, in which each polarizing cell has the same structure as that of the polarizing cell of the Figure 4A , and comprising a lateral support structure which envelops the arrangement of polarizing cells and fixes the positions of electrical discontinuities by making the polarizing cells completely united;
• [ Fig. 11 ] shows a perspective view of a fourth, two-dimensional embodiment of a plane polarizer screen, connected at the input, without a lateral support structure, in which each polarizing cell has the same structure as that of the polarizing cell of the Figure 4A , and comprising two parallel plates for guiding and injecting the input RF signal, connected at the input and at the end to side walls of polarizing cells;
• [ Fig. 12A ] represents a perspective view of a multibeam antenna in which is integrated at the output a polarizing screen with several polarizing cells, similar to that described in the Figures 10A-10B , and the
• [ Fig. 12B ] shows an enlarged view of the longitudinal section of the polarizer screen, connected at the output of the multibeam antenna to a waveguide section for injecting the incident linearly polarized electrical signal.

In general, a polarizing screen according to the invention comprises an arrangement of at least one polarizing cell (s) made of an electrically conductive material, selective in frequency and in polarization, to transform the linear polarization of the electric field E of the incident electromagnetic wave TEM, received as an input and which can be broken down into two electric field signals E _V , E _H whose polarizations are linear and orthogonal, into an electromagnetic output wave of circular polarization.

Each polarizing cell has a waveguide section having two orthogonal pairs of side walls parallel to each other and extended longitudinally along an incident EM wave propagation direction.

According to a first characteristic of the invention, the four side walls of each polarizing cell are each open over their entire length by a continuous median slot, parallel to the direction of propagation of the incident electromagnetic wave, so as to form four folded plates electrically conductive.

According to a second additional characteristic, combined with the first, each polarizing cell includes electrically conductive rods which interconnect the side walls and the four folded plates to make them partially or entirely integral and which form one or more elementary electrical discontinuities, which are arranged at the ends or inside the waveguide section forming the polarizing cell and carry one or more capacitive (s), inductive (s), or equivalent resonator (s) (L, C) to an inductor and a capacitor connected in parallel or in series.

The longitudinal open slits of the side walls and the elementary electrical discontinuities of each polarizing cell have geometric shapes and dimensions which are adjusted so as to achieve a total transmission of the incident electromagnetic wave, associated with a phase anisotropy of + 90 ° or -90 ° depending on the components E _V and E _H.

Following the Figure 1A and a general perspective view of a section of a typical waveguide 10, used in a polarizing cell 12 of a polarizer screen 2 according to the invention, the waveguide section 10 comprises two orthogonal pairs of side walls 24, 25, 26, 27 parallel to each other and extended longitudinally along a direction 32 of propagation of an incident electromagnetic wave TEM (not shown).

According to the first characteristic of the invention, the four side walls 24, 25, 26, 27 of the polarizing cell are each open over their entire length by a median continuous slot 34, 35, 36, 37, parallel to the direction 32 of propagation of the incident electromagnetic wave, so as to form four folded plates 42, 44, 46, 48 electrically conductive.

Following the Figure 1B , the waveguide section 10 with folded parallel plates of the polarizing cell 12 can be represented for a given direction of polarization, parallel to a direction of a pair of corresponding side walls, by a transmission line 52 whose impedance characteristic, denoted Z1, depends on the dimensions of the guided section 10, in particular on the distance between the walls parallel to the considered polarization of the wave, as well as on the opening w of the two longitudinal slits of the side walls of guidance. The transmission line 52 of characteristic impedance Z1 is interposed between input transmission lines 54 and output 56, of characteristic impedance Z0 corresponding to the propagation in a vacuum.

Here, the direction of polarization of the electromagnetic wave considered is the vertical direction V on the Figure 1A , corresponding to the component E _V of the electric field E of the electromagnetic wave in TEM mode (in English “Transversal Electro-Magnetic”) and represented by the vertical arrow 56.

By way of example, the variation of the characteristic impedance is deduced from a characterization of this waveguide structure. The identification of this simplified model with “full wave” simulations makes it possible to identify the characteristic impedance Z1 as a function of w.

In general, the design of a polarizing cell of a polarizing screen according to the invention involves identifying the equivalent circuits associated with the folded-plate waveguide section and with the electrically conductive interconnections between plates or side walls forming one or more successive electrical discontinuities.

Once characterized for each polarization, vertical and horizontal, the electromagnetic circuit (s) equivalent (s) to a guide section, as described in the example of Figures 1A-1B , it is then possible to characterize for each polarization the equivalent circuit (s) of one or more given electrical discontinuity (s), arranged inside the guided section, and each formed electrically conductive interconnection (s) between folded plates or side walls, and thus to model for each polarization the electromagnetic response of a polarizing cell according to the invention having a given configuration in terms of the geometry of the side walls of guiding and longitudinal openings, and the geometry of the interconnections between plates, forming the elementary electrical discontinuities.

Following the Figures 2A and 2C and a same first embodiment, a polarizing cell 112 of a polarizing screen 102 according to the invention is illustrated with a first vertical polarization E _V of the incident electric field E, represented on the figure. Figure 2A by a first vertical arrow 106, and with a second horizontal polarization E _H of the incident electric field E, shown on the Figure 2C by a second horizontal arrow 108, it being assumed that the polarizing cell 112 of the Figure 2A has rotated clockwise by an angle of + 90 ° around the axis 32 of propagation of the TEM wave in the Figure 2A .

The polarizing cell 112 has a waveguide section 120, the four side walls 124, 125, 126, 127 of which are each open longitudinally over the entire length of the guided section 120 by a median continuous slot 134, 135, 136, 137 and a single electrical discontinuity 142, having a vertical component 142 _V and a horizontal component 142 _H , and produced by an H-shaped interconnection 152 of electrically conductive rods.

The H-shaped interconnection 152 realizing the single elementary H-shaped electrical discontinuity 142, arranged inside the waveguide section 120 and substantially in the middle of the length of the polarizing cell 112, consists of two first vertical rods 154, 156 of the same length and of a second horizontal rod 158 connecting substantially in their middle said two vertical rods 154, 156, the first two vertical rods 154, 156 connecting the horizontal pair of parallel side walls, lower 124 and upper 125, so as to produce a first resonator circuit L _V , C _V parallel 142 _V for the first vertical polarization, and a second resonator circuit L _H , C _H parallel 142 _H for the second horizontal polarization, orthogonal to the first vertical polarization .

Following the Figures 2B and 2D corresponding to Figures 2A and 2C in terms of the polarization component, the electrical representation of the polarizing cell 112 for the first vertical polarization is a first transmission line 158 of characteristic impedance Z1 _V , and the electrical representation of the polarizing cell 112 for the horizontal polarization is a second transmission line 160 of characteristic impedance Z1 _H , the first and second transmission lines 158, 160 each being interrupted by the electrical discontinuity 142 along the vertical component 142 _V and the horizontal component 142 _H.

The first and second transmission lines 158, 160, with respective characteristic impedance Z1 _V , Z1 _H , are each interposed between input transmission lines 164 and output 166, characteristic impedance Z0 corresponding to the propagation in the empty.

In general, for an elementary discontinuity corresponding to an interconnection of rods having the shape of an H, a parallel circuit L, C is obtained, the values of which vary according to the dimensions of the H-shaped structure, the values L and C being specific to each polarization.

Following the Figure 3 , and a second embodiment, a polarizing cell 172 of a polarizing screen 162 according to the invention comprises a waveguide section 180 whose four side walls 184, 185, 186, 187 are each open longitudinally over the entire length. length of the guided section 180 by a central continuous slot 194, 195, 196, 197 and a single electrical discontinuity 202, produced by an X-shaped interconnection 204 of rods, electrically conductive and interconnecting the side walls.

The X-shaped interconnection 204 realizing the elementary electrical discontinuity 202, disposed within the waveguide section 180 substantially in the middle of the length of the polarizing cell 172 and symmetrically with respect to a longitudinal median plane 212 traversing the waveguide section 180, consists of two rods 214, 216 of the same length, inclined relative to a vertical direction in the opposite direction, which substantially intersect in their respective middle 224, 226 while being slightly spaced at the level of their middle, and which connect the horizontal pair of parallel side walls, lower 184 and upper 185, whose respective normal is vertical, so as to achieve a first resonator circuit L _V , C _V parallel for a first vertical polarization, and a second parallel resonator circuit L _H , C _H for a second horizontal polarization, orthogonal to the first vertical polarization.

As a variant, the two inclined rods of the X-shaped interconnection substantially cross each other in their respective middle while being connected at their midpoints.

Following the Figure 4A and a third embodiment, a polarizing cell 262 of a polarizing screen 252 according to the invention is illustrated with a first vertical polarization of the incident electric field, represented by a first vertical arrow 256 on the Figure 4A , and a second horizontal polarization of the incident electric field, represented by a second horizontal arrow 258.

The polarizing cell 262 has a waveguide section 270 whose four side walls 274, 275, 276, 277 are each open longitudinally over the entire length of the guided section 270 by a continuous middle slot 284, 285, 286, 287 and two elementary electrical discontinuities 292, 294 each constituted by an interconnection 289, 290 of two parallel poles, 295, 296; 297, 298, not interconnected and electrically conductive.

The two interconnections 289, 290, respectively forming the elementary electrical discontinuities, first 292 and second 294, arranged inside the waveguide section 270 and set back from the respective inlet and outlet ends of said waveguide section. waveguide 270, connect the pair of parallel side walls, lower 274 and upper 275, so as to each achieve an inductive load L _V 299, 300 for a first vertical polarization, parallel to the direction of the vertical rods 295, 296, 297, 298, and a capacitive load C _H 301, 302 for a second horizontal polarization, orthogonal to the first vertical polarization.

Furthermore, it should be noted that the two continuous horizontal median slots 284, 285 of the pair of horizontal side walls, lower 274 and upper 275, of the waveguide section 270 are notched at the entry and exit of the section. of the waveguide 270. The two horizontal slots 284, 286 each pass through two horizontal guide sections and end at the inlet 303 and outlet 304 of the guided section with a first horizontal width W1 _H , and passes through an intermediate guide section horizontal 306 with a second horizontal width W2 _H , less than the first horizontal width W1 _H.

The first electrical discontinuity 292 delimits the horizontal guide section located at the inlet 303 of the guided section in two line portions of transmission of second horizontal polarization having the same first horizontal characteristic impedance Z1 _H and respective lengths d1 and d2 going towards the output of the guided section which has a length denoted d.

The second electrical discontinuity 294 delimits the horizontal guide section located at outlet 304 in two transmission line portions of second horizontal polarization having the same first horizontal characteristic impedance Z1 _H and of respective lengths d2 and d1 going towards the outlet of the section. guided which has a noted length d.

The length of the intermediate guide section 306 is denoted d3 and defines a portion of the transmission line of second horizontal polarization having a second characteristic horizontal impedance Z2 _H.

The two vertical mid-continuous slots of the pair of vertical side walls, left and right, of the waveguide section are devoid of indentations. The two vertical slots each pass through the same vertical guide section over the entire length with the same vertical width W1 _V and a characteristic vertical impedance Z1 _V.

Following the Figure 4B , the electrical representation of the polarizing cell 262 for the first vertical polarization is a first transmission line 309 interrupted by the first inductive load L _V 299 corresponding to the first electrical discontinuity 292 and the first vertical polarization, and the second inductive load 300 of same value L _V , corresponding to the second electrical discontinuity 294, the first and second inductive loads L _V 299, 300 being respectively connected at the input and at the output of the characteristic impedance line portion Z1 _V of length d1.

Following the Figure 4C , the electrical representation of the polarizing cell 262 for the second horizontal polarization is a second transmission line 310 in which the first capacitive load C _H 303, corresponding to the first electrical discontinuity 292 and the second horizontal polarization, is connected to the input of the portion of characteristic impedance line Z1 _H , located downstream of the first discontinuity 292 and of length d2 and the second capacitive load of the same value C _H , corresponding to the second electrical discontinuity and the second horizontal polarization is connected at the output of the portion of characteristic impedance line Z1 _H , located upstream of the second discontinuity and of length d2.

Thus, an interconnection consisting of two vertical metal wires produces an inductive load for the polarization parallel to the wires, and a capacitive load for the polarization orthogonal to the wires.

The first and second transmission lines 309, 310, are each interposed between input transmission lines 311 ₁ and output 311 ₂ , of characteristic impedance Z0 corresponding to the propagation in a vacuum.

Following the Figure 5A , and a fourth embodiment, a polarizing cell 322 of a polarizing screen 312 according to the invention is illustrated with a first vertical polarization of the incident electric field, represented by a first vertical arrow 316 on the Figure 5A , and a second horizontal polarization of the incident electric field, represented by a second horizontal arrow 318.

The polarizing cell 322 has a waveguide section 320 whose four side walls 324, 325, 326, 327 are each open longitudinally over the entire length of the guided section 320 by a continuous middle slot 334, 335, 336, 337 and two elementary electrical discontinuities 342, 344 successive, each constituted by an interconnection 346, 348 in the form of an H and electrically conductive.

The two interconnections 346, 348, forming the two elementary electrical discontinuities 342, 344 and arranged inside the waveguide section 320 and set back from the respective inlet and outlet ends of said waveguide section wave 320, each consist of two first vertical rods 352 ₁ , 352 ₂ ; 354 ₁ , 354 ₂ of the same length and of a second horizontal rod 356, 358 connecting substantially in their middle said two first vertical rods 352 ₁ , 352 ₂ ; 354 ₁ , 354 ₂ the first two vertical rods 352 ₁ , 352 ₂ ; 354 ₁ , 354 ₂ connecting the two vertical parallel side walls, lower 324 and upper 325, so as to each produce a first resonator circuit L1 _V , C1 _V parallel for the first vertical polarization, parallel to the direction of the first interconnection rods , and a second resonator circuit L2 _H , C2 _H parallel for a second horizontal polarization, orthogonal to the first vertical polarization.

Furthermore, it should be noted that the four continuous median slots 334, 335, 336, 337 of the four side walls 324, 325, 326, 327 of the section of the waveguide 320 are here notched at the entry and exit of the section. waveguide.

The two horizontal slots 334, 335 each pass through two horizontal and end guide sections at the inlet and outlet of the guided section with a first horizontal width W1 _H , and through an intermediate horizontal guide section with a second horizontal width W2 _H , less than the first horizontal width W1 _H.

The two entry and exit end sections and horizontal guide each have the same length d1 and each define a portion, first and fifth, of transmission line for the second horizontal polarization having a first horizontal characteristic impedance Z1 _H.

The first electrical discontinuity 342 and the second electrical discontinuity 344 share the intermediate horizontal guide section into three portions, second, third and fourth, of transmission line for the second horizontal polarization, each having the same second horizontal characteristic impedance Z2 _H and respective lengths d2, d3 and d2. The first electrical discontinuity, connected between the second portion and the third portion of the transmission line of the second horizontal polarization, and the second electrical discontinuity, connected between the third and fourth portion of the transmission line of the second horizontal polarization, are separated by the distance d3. The lengths d1, d2, d3, and d here verify the following equality: d = 2 ^∗ d1 + 2 ^∗ d2 + d3, the symbol “ ^∗ ” designating the multiplication operator.

The two vertical slots 336, 337 each pass through two horizontal and end guide sections at the inlet and outlet of the guided section with a first vertical width W1 _V , and pass through an intermediate vertical guide section with a second vertical width W2 _V , less than the first vertical width W1 _V.

The two inlet and outlet and vertical guide end sections each have the same length d1 and each define a portion, first and fifth, of transmission line for the first vertical polarization having a first vertical characteristic impedance Z1 _H.

The first electrical discontinuity 342 and the second electrical discontinuity 344 share the intermediate vertical guide section into three portions, second, third and fourth, of transmission line for the first vertical polarization, each having the same second horizontal characteristic impedance Z2 _H and respective lengths d2, d3 and d2. The first electrical discontinuity, connected between the second portion and the third portion of the transmission line of the first horizontal polarization, and the second electrical discontinuity, connected between the third and fourth portion of the transmission line of the first vertical polarization, are separated by the distance d3. The lengths d1, d2, d3, and d here verify the following equality: d = 2 ^∗ d1 + 2 ^∗ d2 + d3, the symbol “ ^∗ ” designating the multiplication operator.

Following the Figure 5B , the electrical representation of the polarizing cell 322 for the first vertical polarization is a first transmission line 362 in which a first parallel first resonator L1 _V , C1 _V parallel corresponding to the first electrical discontinuity and the first vertical polarization, and a second first parallel resonator L1 _V , parallel C1 _V corresponding to the second electrical discontinuity and the first vertical polarization, are respectively connected at the input of the third portion and at the output of the third portion of the line portion of the intermediate section of second vertical characteristic impedance Z2 _V .

Following the Figure 5C , the electrical representation of the polarizing cell 322 for the second horizontal polarization is a second transmission line 363 in which a first second parallel resonator L2 _H , C2 _H parallel corresponding to the first electrical discontinuity and the second horizontal polarization and a second second resonator parallel L2 _H , parallel C1 _H , corresponding to the second electrical discontinuity and the second horizontal polarization, are respectively connected at the input of the third portion and at the output of the third portion of the line portion of the intermediate section having as characteristic impedance the second horizontal characteristic impedance Z2 _H.

As a variant, the positions of the notches along the horizontal slits and of the vertical slits can differ from one another and / or the positions of the elementary electrical discontinuities with respect to the notches can vary.

Following the Figure 6 , and a fifth embodiment, a polarizing cell 372 of a polarizing screen 364 according to the invention is illustrated with a first vertical polarization of the incident electric field, represented by a first vertical arrow 366 on the Figure 6 , and a second horizontal polarization of the incident electric field, represented by a second horizontal arrow 368.

The polarizing cell 372 has a waveguide section 370 whose four side walls 374, 375, 376, 377 are each open longitudinally over the entire length of the guided section 370 by a continuous middle slot 384, 385, 386, 387 , and two elementary electrical discontinuities 392, 394 each consisting of an interconnection 388, 390, X-shaped rods, electrically conductive and interconnecting the side walls.

The two interconnections 388, 390, respectively forming the two elementary electrical discontinuities, first 392 and second 394, arranged inside the waveguide section 370 forming the polarizing cell 372 and set back from the respective input ends and outlet of said waveguide section 370, and symmetrically with respect to a vertical mid-plane longitudinally crossing the waveguide section, each consist of two rods 392 ₁ , 392 ₂ ; 394 ₁ , 394 ₂ of the same length, inclined with respect to the vertical direction in the opposite direction, which intersect substantially in their respective middle while being connected and which interconnect the horizontal parallel side walls, lower 374 and upper 375, so as to achieve each a first resonator circuit L1 _V , C1 _V parallel for the first vertical polarization, and a second resonator circuit L2 _H , C2 _H parallel for the second horizontal polarization, orthogonal to the first vertical polarization.

Here, like the polarizing cell of the Figure 4A , the two continuous horizontal median slots 384, 385 of the pair of horizontal side walls, lower 374 and upper 375, are notched at the entry and exit of the section of the waveguide 370. The two horizontal slots 384, 385 each pass through two horizontal guide sections and end at the inlet and outlet of the guided section 370 with a first horizontal width W1 _H , and crosses an intermediate horizontal guide section with a second horizontal width W2 _H , less than the first horizontal width W1 _H .

Following the Figure 7A and a sixth embodiment, a polarizing cell 412 of a polarizing screen 402 according to the invention is illustrated with a first vertical polarization of the incident electric field, represented by a first vertical arrow 406 on the Figure 7A , and a second horizontal polarization of the incident electric field, represented by a second horizontal arrow 408.

The polarizing cell 412 includes a waveguide section 410 whose four side walls 414, 415, 416, 417 are each open longitudinally over the entire length of the guided section 410 by a continuous middle slot 424, 425, 426, 427 , two elementary electrical discontinuities, first 432 and second 434, of input and output ends, each formed by an H-shaped interconnection 442, 444 of a first type, and an intermediate electrical discontinuity 436, third, arranged between the first and second elementary end discontinuities 432, 434, and formed by an H-shaped interconnection 446 of a second type.

The two interconnections 442, 444, H-shaped of the first type, first and second, forming the first and second elementary electrical discontinuities 432, 434, arranged inside the waveguide section 410 and set back from the ends respective input and output of said waveguide section 410, each consist of two first vertical rods 452 ₁ , 452 ₂ ; 454 ₁ , 454 ₂ , of the same length and of a second horizontal rod 452 ₃ ; 454 ₃ connecting substantially in their middle said two vertical rods, the two first vertical rods 452 ₁ , 452 ₂ ; 454 ₁ , 454 ₂ connecting a pair of parallel horizontal side walls, lower 414 and upper 415, so as to each produce a first vertical resonator circuit L1 _V , C1 _V parallel to first type for the first vertical polarization, and a first horizontal resonator circuit L1 _H , C1 _H parallel for a second horizontal polarization, orthogonal to the first vertical polarization.

The second, third type H-shaped interconnection 446 forming the third elementary discontinuity 436, disposed within the waveguide section 410 and substantially in the middle of the length of the polarizing cell 412, between the first and second elementary electrical discontinuities 432, 434, consists of two horizontal rods 456 ₁ , 456 ₂ of the same length and of a vertical rod 456 ₃ substantially connecting in their middle said two horizontal rods 456 ₁ , 456 ₂ , the first two rods horizontal 456 ₁ , 456 ₂ connecting the vertical parallel side walls, left 416 and right 417, the normal of which is horizontal, so as to produce a second vertical resonator circuit L2 _V , C2 _V parallel of the second type for the first vertical polarization, and a second parallel horizontal resonator circuit L2 _H , C2 _H of the second type for the second horizontal polarization.

Here, the mid-continuous slits 424, 425, 426, 427 of the four side walls 414, 415, 416, 417 of the waveguide section are devoid of a notch at the entrance and exit of the guide section. wave 410.

The two vertical slots 426, 427 each pass, from the inlet to the outlet, through four vertical guide sections of the guided section with the same vertical width W1 _V. which successively define a portion, first, second, third, fourth, of the transmission line for the first vertical polarization V having the same vertical characteristic impedance Z1 _V.

For the first vertical polarization V, the first portion of the vertical impedance line lying between the entry of the guided section and the first vertical elementary electrical discontinuity of the first type, the second portion of the vertical impedance line lying between the first electrical discontinuity vertical elementary first type and the third vertical elementary electrical discontinuity of the second type, the third portion of vertical impedance line between the third vertical elementary electrical discontinuity of the second type and the second electrical discontinuity vertical elementary first type, and the fourth vertical impedance line portion between the second vertical elementary electrical discontinuity of the first type and the guide section output have respectively first, second, third, fourth length d1, d2, d2, d1 verifying equality: 2 ^∗ (d1 + d2) = d, d denoting the length of the guided section.

The two horizontal slots 424, 425 each pass, from the inlet to the outlet, through four horizontal guide sections of the guided section with the same horizontal width W1 _H. which successively define a portion, first, second, third, fourth, of the transmission line for the second horizontal polarization H having the same horizontal characteristic impedance Z1 _H.

For the second horizontal polarization H, the first horizontal impedance line portion lying between the entry of the guided section and the first horizontal elementary electrical discontinuity of the first type, the second horizontal impedance line portion lying between the first electrical discontinuity horizontal elementary first type and the third horizontal elementary electrical discontinuity of the second type, the third portion of a horizontal impedance line between the third horizontal elementary electrical discontinuity of the second type and the second horizontal elementary electrical discontinuity of the first type, and the fourth portion of horizontal impedance line between the second horizontal elementary electrical discontinuity of the first type and the guide section output respectively have first, second, third, fourth lengths d1, d2, d2, d1 verifying equality: 2 ^∗ ( d1 + d2) = d, d denoting the l length of the guided section.

Following the Figure 7B , the electrical representation of the polarizing cell 412 for the first vertical polarization is a first transmission line 462 in which a first parallel resonator L1 _V , C1 _V parallel corresponding to the first electrical discontinuity of the first type and the first vertical polarization, a second first parallel resonator L1 _V , C1 _V parallel corresponding to the second electrical discontinuity of the first type and the first vertical polarization, and a single second resonator L2 _V , C2 _V parallel corresponding to the third electrical discontinuity of the second type and the first vertical polarization are respectively connected at the input of the second portion, at the output of the third portion and at the input of the third portion of the first transmission line 452.

Following the Figure 7C , the electrical representation of the polarizing cell 412 for the second horizontal polarization is a second transmission line 464 in which a first parallel resonator L1 _H , C1 _H parallel corresponding to the first electrical discontinuity of the first type and the second horizontal polarization, a second first resonator L1 _H , C1 _H parallel corresponding to the second electrical discontinuity of the first type and the second vertical polarization, and a single second resonator L2 _H , C2 _H parallel corresponding to the third electrical discontinuity of the second type and the second horizontal polarization are respectively connected at the input of the second portion, at the output of the third portion and at the input of the third portion of the second transmission line 454.

In general, the polarizing cell includes an elementary electrical discontinuity or a succession of elementary electrical discontinuities forming capacitive or inductive loads, or L, C, parallel or series circuits which make it possible to model the polarizing cell as a band-pass circuit for each of the vertical and horizontal polarizations.

Generally, the waveguide sections and the interconnection rods forming each polarizing cell are electrically conductive.

According to a first embodiment, the waveguide sections and the interconnection rods forming each polarizing cell consist of a single homogeneous electrically conductive material.

According to a second embodiment, the waveguide sections and the interconnection rods forming each polarizing cell consist of a single homogeneous electrically conductive material.

In particular, the only homogeneous electrically conductive material is a metal, or the second electrically conductive material is a metal.

When the structure of the polarizing cell (s) of the polarizing screen is entirely metallic, the polarizing screen exhibits low transmission losses regardless of the transmission or reception mode of the application used, and is compatible with high power applications.

An entirely metallic structure of the polarizing cells makes it possible to produce the polarizing screen according to the invention by additive manufacturing using a 3-D printing process.

The polarizing cells of the polarizing screen according to the invention have a very wide passband and lateral guiding walls that are thin with respect to the transmission wavelength. The use of guided sections based on folded parallel plates makes it possible not to introduce frequency dispersion in the waveguide sections and to obtain very wide band responses. The small thickness of the side walls of the guided sections, typically less than the transmission wavelength, gives the polarizing screen stability in incidence of the injected electromagnetic wave.

Following the Figure 8 and a first embodiment, a polarizer screen 502 is a continuous and periodic two-dimensional arrangement of polarizing cells 512, fitted on a planar surface and having a structure identical to that of the polarizing cell of the Figure 7A .

The polarizing cells 512 are here formed by metal guided sections 510 open at the sides by longitudinal openings. Thanks to the longitudinal openings, the guides can propagate a TEM mode, which is not subject to a cutoff frequency.

The guided sections 510 are loaded in several places by metallic patterns of various shapes, joining the walls of the guides, here three H-shaped metallic patterns. These patterns make it possible to join together the different parts of the structure of each polarizing cell and achieve generally inductive or capacitive type electrical charges, or parallel or (L, C) series (L, C) resonators.

Here, the metal patterns having the shape of H and connecting the four folds of each guided section, produce resonators (L, C) parallel according to the two polarizations whose values L and C for each polarization are determined. by the geometry of said patterns. The width of the guided section and the width of the longitudinal openings, here four slots of the same width will determine the characteristic impedance of the guided section.

Thanks to the absence of a cut-off frequency, the periodic arrangement of the guided sections can be small with respect to the wavelength (typically λ / 3). Very wide passbands can be obtained, for example making it possible to cover the Rx and Tx subbands of the Ka band. The frequency response of the screen according to each polarization is mainly determined by the capacitive and inductive loads carried out by the metal connections, and the characteristic impedances determined by the characteristics of the frame, acting as a waveguide with parallel plates.

Following the Figures 9A to 9C , the radio performance of a two-dimensional plane polarizer screen, having polarizing cells identical to those of the Figure 4A , are illustrated.

Following the Figure 9A , the curves 552, 554, 556, 558 of the evolution of the parameters S (transmission gain S ₂₁ and return loss S ₁₁ ) as a function of the frequency show the adaptation for a wide frequency band Ka for the two electrical components E _V and E _H of the incident electromagnetic wave, corresponding respectively to the first vertical polarization and to the second horizontal polarization.

Following the Figure 9B , the evolution of the phase difference between the two transmission coefficients for the two electrical components E _V and E _H of the incident electromagnetic wave as a function of the frequency is illustrated.

Curve 662 describes the change in the transmission coefficient for the vertical component E _V of the incident electromagnetic wave, ie the first vertical polarization as a function of frequency.

Curve 664 describes the change in the transmission coefficient for the horizontal component E _H of the incident electromagnetic wave, ie the second polarization as a function of frequency.

A 90 ° anisotropy between the two curves 662 and 664 is visible on the 660 frequency band between 20 GHz and 28 GHz.

Following the Figure 9C , the evolution of the ellipticity rate AR (in English "Axial Ratio") as a function of a frequency shows an ellipticity rate close to 0 (less than 1dB) on the frequency band.

Following the Figures 10A and 10B and a second embodiment, a planar two-dimensional polarizer screen 702 according to the invention is connected as input to a waveguide section 706 for injecting an incident electromagnetic wave polarized linearly.

The polarizer screen 702 is here a continuous and periodic two-dimensional planar arrangement of polarizing cells 712 each having the same structure as that described in Figure 4A .

The waveguide section 706 for injecting a linearly polarized incident electromagnetic wave here comprises a flare 714, configured to modify the impedance of the parallel plate guide 716 which precedes it upstream by matching it to the impedance input of the polarizer screen. The larger the flare, the closer the characteristic impedance will be to that of a vacuum. In this case the electrical diagrams of the polarizer screen 702 for the two orthogonal polarizations are similar to those of the Figures 4A and 4B in which the characteristic input impedance Z0 of the screen corresponding to a propagation in vacuum has been replaced by an impedance Zpp corresponding to the characteristic output impedance of the flare.

The polarizer screen 702 further comprises a lateral support structure 720 which laterally envelops the polarizing cells 712 arranged between them, and on which are fixed the ends of rods 724 making the polarizing cells partially integral with each other.

Here, the polarizing cells 712 are made integral with each other in their entirety by the joint action, on the one hand of the rods 720 passing through the walls of guide sections of polarizing cells 712 in the same lateral direction, here the vertical direction of each cell polarizing, parallel to the first direction of vertical polarization which corresponds to the direction of the incident E _V field inclined by 45 ° with respect to the vertical direction of the Figure 10B , and on the other hand the support structure 720 which fixes the position of the connecting rods 724.

The polarizer screen 702 is attached to the input waveguide section 706 by two sets of polarizing cell waveguide section wall input end fasteners 712, configured to be rigidly connected to walls. sides of the waveguide 706.

As a variant, the input waveguide is replaced by an injection horn output of the incident electromagnetic wave.

Following the Figure 11 and a third embodiment, a plane polarizer screen 802 according to the invention is, like the two-dimensional plane polarizer screen 702 of the Figures 10A-10B , a two-dimensional planar, continuous and periodic arrangement of polarizing cells 812 each having the same structure as that described in Figure 4A .

Unlike the polarizer screen 702 of the Figures 10A-10B , the polarizer screen 802 has no lateral support structure but comprises two plates 806 ₁ , 806 ₂ for guiding and injecting the input signal connected at the input to the assembly of the waveguide sections forming the arrangement of polarizing cells. These parallel plates may include a flare.

Here, the polarizing cells are made integral with each other in their entirety by the joint action, on the one hand of the rods 820 passing through the walls of guide sections of polarizing cells aligned in the same lateral direction, here the vertical direction of each polarizing cell , parallel to the first direction of vertical polarization which corresponds to the direction of the incident field E inclined by 45 ° with respect to the vertical direction of the Figure 11B , and on the other hand the two plates 806 ₁ , 806 ₂ for guiding and injecting the input RF signal which fix the positions of the grouped connection rods of plates folded back through links at the end of at least one plate folded back by groups of folded plates of the waveguide sections.

The polarizing cell arrangement is attached at the input end to the two guiding and injection plates of the input RF signal by two sets of input end fasteners of folded plates of walls of waveguide sections polarizing cells, configured to be rigidly connected to the two guiding and injection plates of the linearly polarized input RF signal.

Alternatively, in the second and third embodiments of Figures 10A-10B and Figure 1 , several parallel plate injection waveguides can be superimposed. These parallel plate injection waveguides can end with several superimposed flares.

Following the Figures 12A-12B and an example of use of a polarizer screen according to the invention, a plane two-dimensional polarizer screen 902, of identical structure to that of the Figures 10A-10B is integrated into a multibeam antenna 904, formed by an array 906 of linearly polarized TEM wave RF sources 908 and a beamformator 910 as described in the patent FR 3038457 B1 . The beamformer 910 is a waveguide having parallel plates for forming several beams over a wide angular sector. The RF sources 908 which feed the beam former 910 are here of the horn type, four of them being represented here.

The multibeam antenna 904 is configured to radiate from a continuous aperture, formed by a waveguide section 912 for injecting a linearly polarized incident electromagnetic wave similar to that described in Figures 10A-10B .

The polarizer screen 902 is a planar, continuous and periodic two-dimensional arrangement of polarizing cells 932 each having the same structure as that described in Figure 4A . The polarizer screen 902 further comprises a lateral support structure 936 which laterally envelops the polarizing cells 932 arranged between them, and on which are fixed the ends of rods making the polarizing cells partially integral with each other.

The polarizer screen 902 is connected to the output of the waveguide section 912 for injecting an incident electromagnetic wave linearly polarized in a manner similar to that described in Figures 10A-10B .

A method of manufacturing a polarizing screen according to the invention as described above can advantageously use a 3D printing technique, when the polarizing cells (guided sections and interconnection rods) are completely metallic.

The polarizing cells according to the invention are dimensioned to operate in a frequency band included in one of the bands L, S, C, Ku and Ka

• des antennes bord multifaisceaux embarquées à bord de satellites de systèmes de télécommunications spatiales, basés sur des constellations de satellites évoluant en orbite basse LEO (en anglais « Low Earth Orbit ») ou moyenne MEO (en anglais « Medium Earth Orbit ») ;
• des antennes de terminaux de communication SATCOM ; ou
• des terminaux utilisateur de systèmes de télécommunications basés sur des constellations de satellites en orbite basse LEO ou moyenne MEO.

Several applications can be covered by a polarizer screen according to the invention as described above, such as for example:

• multibeam on-board antennas on board space telecommunications system satellites, based on constellations of satellites operating in low orbit LEO ("Low Earth Orbit") or medium MEO ("Medium Earth Orbit");
• SATCOM communication terminal antennas; or
• user terminals of telecommunications systems based on constellations of satellites in low orbit LEO or medium MEO.

Claims (14)

Polarizer screen, comprising an arrangement of at least one polarizing cell (s) (112; 172; 262; 312; 372; 412; 512; 932), made of an electrically conductive material, selective (s) ) in frequency and polarization, to transform the linear polarization of the electric field E of an incident electromagnetic wave TEM, received at the input and decomposable into two electric field signals E _V , E _H whose vertical and horizontal polarizations are linear and orthogonal , in circular polarization of an output electric field, and wherein each polarizing cell (112; 172; 262; 312; 372; 412; 512; 932), has a waveguide section having two orthogonal pairs, vertical and horizontal, side walls parallel to each other and extended longitudinally along a direction of propagation of an incident EMT electromagnetic wave,
the polarizer screen being characterized in that
the four side walls (124, 125, 126, 127; 194, 195, 196, 197; 274, 275, 276, 277; 324, 325, 326, 327; 374, 375, 376, 377; 414, 415, 416 , 417) of each polarizing cell (112; 172; 262; 312; 372; 412; 512; 932) are each open over their entire length by a continuous median slot (134, 135, 136, 137; 194, 195, 196 , 197; 284, 285, 286, 287; 324, 325, 326, 327; 384, 385, 386, 387; 424, 425, 426, 427), parallel to the direction of propagation of the incident electromagnetic wave, from so as to form four folded electrically conductive plates, and
each polarizing cell includes electrically conductive rods which interconnect the side walls and the four folded plates to make them partially or entirely integral and which form one or more successive elementary electrical discontinuities, which are arranged at the end or inside the section waveguide forming the polarizing cell and carry one or more capacitive (s), inductive (s), or one or more resonator (s) equivalent (S) (L, C) to an inductor and a capacitor connected in parallel or in series; and
the longitudinally open slots (134, 135, 136, 137; 194, 195, 196, 197; 284, 285, 286, 287; 324, 325, 326, 327; 384, 385, 386, 387; 424, 425, 426, 427), side walls and the elementary electrical discontinuities of each polarizing cell comprise geometric shapes and dimensions which achieve total transmission of the incident wave, associated with a phase anisotropy of + 90 ° or -90 ° depending on the components E _V and E _H. A polarizer screen according to claim 1, wherein the waveguide sections and the interconnection rods, forming each polarizing cell, electrically conductive, consist of: a single homogeneous electrically conductive material, or a first material covered by a second electrically conductive material. A polarizer screen according to claim 2, wherein the single homogeneous electrically conductive material is a metal, or the second electrically conductive material is a metal. Polarizer screen according to one of claims 1 to 3 wherein,
the median continuous slits of the four side walls of each waveguide section forming a polarizing cell, are notched at the input and at the output of the waveguide section; or
the continuous median slots of a single pair of parallel side walls of each waveguide section forming a polarizing cell, are notched at the input and at the output of the waveguide section; or
the median continuous slits of the four side walls of each waveguide section forming a polarizing cell, are devoid of notches at the entry and exit of the waveguide section. Polarizer screen according to one of claims 1 to 4 in which,
The polarizing cells (112; 172; 262; 312; 372; 412; 512; 932) are sized to operate in a frequency band included in one of the L, S, C, Ku and Ka bands. Polarizer screen according to one of claims 1 to 5, in which
each polarizing cell (112) includes rods of electrically conductive material, interconnecting the side walls in an H-shaped interconnection, making a single elementary electrical discontinuity, and the H-shaped interconnection forming the elementary electrical discontinuity, arranged inside the waveguide section and substantially in the middle of the length of the polarizing cell, consists of two first vertical rods of the same length and of a second horizontal rod connecting approximately in their middle said two vertical rods, the first two vertical rods connecting a pair of horizontal, lower and upper side walls, so as to produce a first resonator circuit L _V , C _V parallel for a first vertical polarization, and a second resonator circuit L _H , C _H parallel for a second horizontal polarization, orthogonal to the first vertical polarization. Polarizer screen according to one of claims 1 to 5, in which
each polarizing cell (172), includes rods of electrically conductive material, X-shaped interconnecting side walls providing a single elementary electrical discontinuity, and
the X-shaped interconnection providing the single elementary electrical discontinuity, arranged inside the waveguide section substantially in the middle of the length of the polarizing cell and symmetrically with respect to a longitudinal median plane crossing the section of waveguide, consists of two rods of the same length, inclined with respect to a vertical direction in the opposite direction, which cross each other substantially in their respective middle while being connected or slightly distant at the level of their middle, and which connect a pair horizontal side walls, lower and upper, so as to produce a first resonator circuit L _V , C _V parallel for a first vertical polarization, and a second resonator circuit L _H , C _H parallel for a second horizontal polarization, orthogonal to the first vertical polarization. Polarizer screen according to one of claims 1 to 5, in which
each polarizing cell (262), includes rods of electrically conductive material, interconnecting the side walls, in two interconnections, each formed by two vertical rods or vertical posts without a central connection between them, and each making an elementary electrical interconnection; and
the two interconnections, first and second, making the two elementary electrical discontinuities, arranged inside the waveguide section forming the polarizing cell and set back from the respective inlet and outlet ends of said guide section d 'wave, connect the two horizontal side walls, lower and upper, so as to achieve an inductive load for the first vertical polarization, parallel to the direction of the vertical rods, and a capacitive load for the second horizontal polarization, orthogonal to the first polarization vertical. Polarizer screen according to one of claims 1 to 5, in which
each polarizing cell (312) includes rods made of an electrically conductive material, interconnecting the side walls along two successive H-shaped interconnections, forming two elementary electrical discontinuities; and
the two successive interconnections, first and second, forming the two elementary discontinuities, arranged inside the waveguide section forming the polarizing cell and set back from the respective inlet and outlet ends of said guide section d 'wave, each consist of two first vertical rods of the same length and a second horizontal rod connecting substantially in their middle said two vertical rods, the first two vertical rods connecting the horizontal side walls, lower and upper, so as to achieve each a first resonator circuit L _V , C _V parallel for the first vertical polarization, and a second resonator circuit L _H , C _H parallel for the second horizontal polarization, orthogonal to the first vertical polarization. Polarizer screen according to one of claims 1 to 5, in which
each polarizing cell (372) includes rods of electrically conductive material, interconnecting the side walls along two X-shaped interconnections, making two elementary electrical discontinuities; and
the two successive interconnections, first and second, forming the two elementary discontinuities, arranged inside the waveguide section forming the polarizing cell and set back from the respective inlet and outlet ends of said guide section d 'wave and symmetrically with respect to a vertical median plane longitudinally crossing the waveguide section, each consist of two rods of the same length, inclined with respect to a vertical direction in the opposite direction, which intersect substantially in their respective middle by being connected or slightly distant at the level of their middle, and which connect the two horizontal side walls, lower and upper,
so as to each produce a first resonator circuit L _V , C _V parallel for the first vertical polarization, and a second resonator circuit L _H , C _H parallel for the second horizontal polarization, orthogonal to the first vertical polarization. Polarizer screen according to one of claims 1 to 5, in which
each polarizing cell (412) includes rods made of electrically conductive material, interconnecting the side walls along two interconnections, first and second, in the form of an H of a first type, producing two elementary electrical discontinuities of a first type and following a third H-shaped interconnection of a second type, producing an elementary electrical discontinuity of a second type; and
the two H-shaped interconnects of the first, first and second type, arranged inside the waveguide section forming the polarizing cell and set back from the respective inlet and outlet ends of said guide section d 'wave, each consist of two first vertical rods of the same length and of a second horizontal rod connecting substantially in their middle said two vertical rods, the first two vertical rods connecting the two horizontal side walls, lower and upper, so as to each perform a first parallel resonator circuit L _V1 , C _V1 of the first type for a first vertical polarization, and a second resonator circuit L _H1 , C _H1 parallel for a second horizontal polarization, orthogonal to the first vertical polarization; and
the second, third type H-shaped interconnect, disposed within the waveguide section and substantially in the middle of the length of the polarizing cell, consists of two third horizontal rods of the same length and a fourth vertical rod connecting substantially in their middle said two third horizontal rods, the two third horizontal rods connecting the vertical side walls, left and right, so as to produce a first parallel resonator circuit L _V2 , C _V2 of the second type for the first vertical polarization, and a second parallel resonator circuit L _H2 , C _H2 of the second type for the second horizontal polarization. Polarizer screen according to one of claims 1 to 11, further comprising
a lateral support structure (720) which laterally envelops the arrangement of the polarizing cells and on which are fixed the ends of rods making each polarizing cell partially or totally integral; or
two parallel plates for guiding and injecting (706) the incident electrical signal, linearly polarized, fixed at the end of polarizing cell walls so as to make the polarizing cells of the polarizing screen integral with one another with interconnection rods integral with groups of polarizing cells. A polarizer screen according to one of claims 1 to 12, wherein the arrangement of the polarizing cells is a continuous two-dimensional arrangement of at least three polarizing cells (512) fitted on a regular surface. Method of manufacturing a polarizer screen, as defined by one of claims 1 to 13, characterized in that
the polarizer screen is entirely metallic, and
the manufacturing process uses a 3D printing technique

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