EP4262024A1 - Device for controlling rf electromagnetic beams according to their frequency band and manufacturing method - Google Patents

Abstract

A device (300) for controlling radio frequency beams of given polarization is proposed, the device comprising a set of at least one cell (400), comprising a support frame (420) and at least one interconnection (460) internal to the frame. The frame is inscribed in a prism, having a given Z' axis and faces connected together by edges oriented along the Z' axis. The frame comprises corner elements, each having an edge coinciding with an edge and being arranged such that the frame has, on each face, a slot (440-n) extending along the axis Z'. The interconnection comprises inductive rods (462-n), each comprising two ends of which a first end is connected to an edge, the second ends being connected together at a connection point positioned at the center of the frame in a plane orthogonal to the Z' axis. Each cell is configured to achieve polarization invariant beam transmission and/or reflection.

Description

Technical area

The present invention relates generally to the field of radio frequencies (RF), and in particular to a device for controlling RF electromagnetic beams according to their frequency band, in particular for controlling the reflection and/or transmission of electromagnetic beams, as well as a process for manufacturing such a device. An example of a control device is described in the patent FR 3095303 B1 .

Devices for controlling the reflection and/or transmission of beams coming from RF electromagnetic signal sources, depending on their frequency band, also called "RF dichroic screens", can be made up of frequency selective surfaces or FSS (acronym for “Frequency Selective Surfaces”, according to the corresponding Anglo-Saxon expression). Such surfaces are formed from a stack of two or more periodic surfaces, themselves designed from metallic patterns regularly distributed according to a periodicity vector, engraved or printed on a dielectric substrate.

The metal patterns usually chosen are annular type patterns to constitute resonant elements whose interaction with RF electromagnetic signals is modeled according to a circuit comprising a coil (defined by an inductance L) and a capacitor (defined by a capacitance C) , with a predominant capacitive part. These periodic surfaces are called 'capacitive'. An RF dichroic shield designed from such capacitive surfaces reflects in a high frequency band and transmits in a lower frequency band so it is typically used as a low pass (or notch) filter.

However, when transmitting RF electromagnetic signals from a source, the RF powers of the emitted beams are usually lower in a high frequency band than in a lower frequency band. The reflection phenomenon induces less power losses compared to the transmission phenomenon. Also, to minimize the power dissipated inside of the structure, it is desirable that an RF dichroic screen reflects an RF signal having a low frequency band. The RF signal then penetrates little into the RF dichroic screen, and is less likely to be affected by ohmic losses (ie power losses). For this, it is known to use an RF dichroic screen behaving like a highly reflective metal plate for the low frequency band.

Furthermore, a degraded surface condition of an RF dichroic screen produces more disturbances on the wavefront of a reflected RF beam than on the wavefront of a transmitted RF beam. However, the production of these disturbances is all the more important for a high frequency band than for a lower frequency band. Thus, it is also desirable that the RF dichroic screen behaves like a high-pass filter, therefore operating transparently in a high frequency band.

The dielectric substrates constituting these periodic surfaces also induce ohmic losses on the transmitted RF beam which can be minimized, but cannot be canceled.

On the other hand, increasing the number of periodic capacitive surfaces constituting such a dichroic RF screen used as a notch filter, can allow a widening of the passing frequency band of the transmitted RF beam. However, considering that an RF beam to be transmitted has a non-zero angle of incidence with respect to the normal of the RF dichroic screen, the thicker the structure of the RF dichroic screen (ie, the number of periodic surfaces is important), the more sensitive this structure becomes to this angle of incidence. The thickness of the structure and the spacings between the periodic surfaces evolves inversely proportional to the cosine of the angle of incidence of the RF beam to be transmitted, as described in the article " A Low-Profile Third-Order Bandpass Frequency Selective Surface" by N. Behdad et al. Antennas and Propagation, IEEE Transactions on, 2009, pages. 460-466 .

It is also known to use RF dichroic screens formed from perforated plates. Such RF dichroic screens are frequently used as bandpass filters. These perforated plates are made up of metal sheets perforated at a given frequency, with rectangular or circular holes, as described in the article "Transmission and reflection of metallic mesh in the far infrared" by P. Vogel et al. Infrared Physics, 1964, vol. 4, pp. 257-262 .

The perforations act as waveguides for RF electromagnetic beams of wavelength λ , for which the RF dichroic screen must be transparent. These perforations must be large enough for an electromagnetic mode to be established there. The periodicity associated with these perforations is typically of the order of 0.75 λ . However, grating lobes can be excited there for beams with a large opening angle and/or having a non-zero angle of incidence relative to the normal of the RF dichroic screen. The periodicity of these perforations thus constitutes a first constraint, due to the fact that it limits the angle of incidence for which the RF dichroic screen can be used and/or the opening angle of the RF beam (since it results in significant losses for too large an angular sector, for example greater than 40°).

A second constraint corresponds to the effects of partial reflections in the planes of discontinuities, for beams in transmission in these waveguides. These partial reflections depend on the quantity of metal constituting the perforated plates and are all the more important as the metal walls are thick. Partial reflections at the input and output of the waveguides can be compensated at a given frequency, by adjusting the length of the guided sections. However, around this given frequency and over an angular sector, the recombination of partial reflections produces a ripple in the frequency band, which can reach several tenths of a dB.

Finally, considering that RF sources produce RF electromagnetic waves in TEM mode (in English “Transversal Electro-Magnetic”), a third constraint linked to these perforations is linked to the fact that the reflection and transmission coefficients of such dichroic screens RF depend on the TE or TM polarization of the incident wave.

A classic solution to address the constraints associated with these perforations consists of reducing the periodicity by considering the propagation in dielectric media. However, this results in significant dielectric losses and increased complexity of the manufacturing process.

Polarization invariance of RF dichroic displays is an important need. Indeed, the polarization (in particular circular) of the wave transmitted or reflected by the screen must not or only slightly be disturbed, to avoid inducing significant losses and non-negligible changes depending on the angle of incidence. of the harness, as described in the article " Upgrade to the K-band uplink channel for the ESA Deep Space Antennas: Analysis of the optics and preliminary dichroic mirror design" by M. Marchetti et al. 14th European Conference on Antennas and Propagation (EuCAP), Copenhagen, Denmark, 2020 .

It is also known to improve certain properties of RF dichroic screens by using RF electromagnetic waveguides having a so-called “under-cut” structure, that is to say not allowing propagation of a guided mode that 'beyond the cut-off frequency which is greater than the desired operating frequency.

To manufacture such waveguides, the walls (or walls) of the perforations have slots in order to produce transmission frequency windows at the resonance frequency of the slots, as described in the article " Waveguide 3-D FSSs by 3-D printing technique" by T. Wang et al. International Conference on Electromagnetics in Advance Applications (ICEAA), Cairns, Australia, 2016 .

The waveguides thus created therefore operate with a much lower periodicity, typically of the order of 0.5 λ , in the frequency band λ for which the RF dichroic screen must be transparent. Slots can take multiple shapes, as described in the article " Circuit Modeling of 3-D Cells to Design Versatile Full-Metal Polarizers" by C. Molero et al. IEEE Transactions on Microwave Theory and Techniques, 2019, vol. 67, pp. 1357-1369 .

However, the structure of these waveguides is very resonant, and therefore limits the bandwidth of the transmitted RF beam. To expand the bandwidth, it is then necessary to add resonators to the walls. This results in a structure having a significant thickness compared to the wavelength of the frequency bands. This thickness gives too much sensitivity in relation to the angular sector, that is to say the opening angle of the RF beams and/or the angle of incidence of the beams in relation to the normal of the dichroic screen RF.

Such RF dichroic screens are nevertheless entirely metallic and therefore suitable for applications with high power beams. However, as described previously, the metal RF dichroic screens known to those skilled in the art have responses depending on the polarization of the beams, which are not stable over a wide bandwidth and over a wide angular sector of incidence (in particular limited to a beam of opening angle ±5° around an angle of incidence of 30° for example).

There is thus a need for an improved device making it possible to control beams of RF electromagnetic waves in TEM (“Transversal Electro-Magnetic”) mode according to their frequency band.

Summary of the invention

faces $P_n$

reliées entre elles par

arêtes

orientées selon l'axe du prisme Z', le cadre de support comprenant

éléments de coin, chaque élément de coin ayant un bord coïncidant avec une des arêtes du prisme, les éléments de coins étant agencés de sorte que le cadre de support présente, sur chaque face du prisme, une fente s'étendant selon l'axe du prisme Z'. Chaque interconnexion interne comprend

tiges inductives comprenant chacune deux extrémités, les tiges inductives ayant chacune une première extrémité reliée à un des bords du cadre de support, les deuxièmes extrémités des tiges inductives étant reliées entre elles au niveau d'un point de connexion de tiges, le point de connexion de tiges étant positionné sensiblement au centre du cadre de support dans un plan orthogonal à l'axe du prisme Z'. Chaque cellule est configurée pour réaliser une transmission et/ou une réflexion de faisceaux radiofréquences invariante en polarisation des ondes électromagnétiques TEM.The present invention improves the situation by proposing a radio frequency beam control device comprising a set of at least one cell, the cell comprising a support frame and at least one internal interconnection to the support frame, the radio frequency beams being waves electromagnetic TEM having a given polarization. Advantageously, the support frame is inscribed in a prism, having a given axis Z', the prism comprising

faces $P_{\mathrm{not}}$

linked together by

edges

oriented along the axis of the prism Z', the support frame comprising

corner elements, each corner element having an edge coinciding with one of the edges of the prism, the corner elements being arranged so that the support frame has, on each face of the prism, a slot extending along the axis of the prism Z'. Each internal interconnection includes

inductive rods each comprising two ends, the inductive rods each having a first end connected to one of the edges of the support frame, the second ends of the inductive rods being connected together at a rod connection point, the connection point of rods being positioned substantially in the center of the support frame in a plane orthogonal to the axis of the prism Z'. Each cell is configured to carry out polarization-invariant transmission and/or reflection of radiofrequency beams of TEM electromagnetic waves.

In a particular embodiment, a cell may comprise at least two internal interconnections and in addition at least one capacitive plate internal to the support frame extending in a plane orthogonal to the axis of the prism Z', the at least one capacitive plate being arranged between the two internal interconnections.

According to embodiments, a cell may comprise at least two internal interconnections and in addition at least one central pillar extending along the axis of the prism Z' and being arranged substantially in the center of the support frame, the central pillar comprising a upper end connected to the rod connection point of one of the internal interconnections, and a lower end connected to the rod connection point of another internal interconnection.

Advantageously, the at least one capacitive plate can be connected to the support frame by at least one central pillar extending along the axis of the prism Z' and comprising an upper end and a lower end, the capacitive plate being arranged substantially in the middle of the central pillar.

The at least one capacitive plate can be held inside the support frame by means of a dielectric support.

The radio frequency beam control device may be made of a single electrically conductive material.

peut être égal à 4 tandis que le cadre de support a une forme de parallélépipède carré, ou le nombre

peut être égal à 6 tandis que le cadre de support ayant une forme de prisme hexagonal.In particular the number

can be equal to 4 while the support frame has a square parallelepiped shape, or the number

can be equal to 6 while the support frame having a hexagonal prism shape.

The radio frequency beam control device can be defined in a reference frame (X,Y,Z) and generally extend in a plane (X,Y), and the axis of the prism Z' can be parallel to the axis Z , the support frame having the shape of a right prism.

Alternatively, the radio frequency beam control device can be defined in a reference frame (X,Y,Z) and generally extend in a plane (X,Y), and the axis of the prism Z' can have an inclination β by relative to the Z axis, the support frame having the shape of an oblique prism.

In certain embodiments, the inductive rods and the edges of the support frame can form an angle γ of between 45° and 90°, and/or between 90° and 135°.

The radio frequency beam control device can be defined in a reference frame (X,Y,Z), generally extend in a plane (X,Y), and comprise a set of several cells having geometric shapes and variable dimensions in the plane (X,Y).

The invention also provides an optical system comprising at least a first source of radio frequency signals configured to emit a radio frequency beam of frequency band λ ₁ in a given direction of propagation and an RF beam control device, the beam control device radio frequencies being configured to reflect and/or transmit the radio frequency beam according to the given direction of propagation and the frequency band Al.

In certain embodiments, the optical system may comprise at least two sources of radio frequency signals, the sources comprising a second source configured to emit a radio frequency beam of frequency band λ ₂ in a given propagation direction, the beam control device radio frequencies being defined in a reference frame (X,Y,Z) and generally extending in a plane (X,Y), the control device being configured to reflect the radiofrequency signals of frequency band λ ₁ and transmit the radiofrequency signals of frequency band λ ₂ , the radio frequency beam control device being positioned between the sources, the Z axis having an angle of incidence α _i relative to the sources, for example α _i = 30°.

The radio frequency beam emitted by the first source may be a TEM electromagnetic wave having a given phase, and the radio frequency beam control device may be defined in a reference frame (X,Y,Z) and generally extend in a plane (X ,Y), the control device comprising a set of several cells, the radiofrequency beam control device being configured to modify the phase in the plane (X,Y).

Furthermore, the invention provides a method of manufacturing the radio frequency beam control device, the device being entirely metallic, and the manufacturing method using at least one 3D printing technique.

The radio frequency beam control device comprising two faces defined in the plane (X,Y), the method can comprise a first step of depositing layers of metal stacked in the direction of said inclination β, then a second step of cutting at least one of the two faces of the device.

The embodiments of the invention thus provide a device for controlling RF electromagnetic wave beams in TEM mode, capable of being invariant with respect to polarization, adapted to high power RF signals, and behaving like a Dichroic screen of high-pass filter type, that is to say operating in reflection in a low frequency band and in transparency in a higher frequency band, with very low insertion losses, for large angular sectors incident RF beams.

The device according to the embodiments of the invention makes it possible to control beams of RF electromagnetic waves in TEM mode, according to their frequency band in a manner invariant with respect to the polarization. Such a device can for example be produced in the form of a dichroic screen of the high-pass filter type, operating in reflection in a low frequency band (for example X band) and in transparency in a higher frequency band (for example example Ka band), according to very low insertion losses.

Such a device is particularly suitable for new additive manufacturing processes which improve the performance of reflection and transmission of wide bands, according to a large angular sector of the beams of RF electromagnetic signals at incidence, and of high power.

Description of figures

• [Fig.1] La figure 1 est un schéma représentant un système optique comprenant un dispositif de contrôle de faisceaux radiofréquences, selon des modes de réalisation de l'invention.
• [Fig.2] La figure 2 est un schéma représentant le cadre de support d'une cellule du dispositif de contrôle de faisceaux radiofréquences selon des modes de l'invention.
• [Fig.3] La figure 3 est une vue en perspective d'une cellule du dispositif de contrôle de faisceaux radiofréquences montrant le cadre de support et une interconnexion interne de la cellule, selon des modes de l'invention.
• [Fig.4] La figure 4 est une vue en perspective d'une cellule du dispositif de contrôle de faisceaux radiofréquences montrant le cadre de support et deux interconnexions internes à la cellule, selon des modes de l'invention.
• [Fig.5] La figure 5 représente un circuit équivalent modélisé à partir de cellules du dispositif de contrôle de faisceaux RF, selon deux schémas (a) et (b), dans des modes de l'invention.
• [Fig.6] La figure 6 est une vue en perspective d'une cellule du dispositif de contrôle de faisceaux RF montrant le cadre de support, deux interconnexions internes et un plateau interne à la cellule, selon des modes de l'invention.
• [Fig.7] La figure 7 est un tableau illustrant la construction de successions de charges interne à une cellule du dispositif de contrôle de faisceaux RF, selon des modes de l'invention.
• [Fig.8] La figure 8 est une vue en perspective d'une cellule du dispositif de contrôle de faisceaux radiofréquences montrant le cadre de support, deux interconnexions internes et un pilier central à la cellule, selon des modes de l'invention.
• [Fig.9] La figure 9 est une vue en perspective d'un ensemble de cellules du dispositif de contrôle de faisceaux RF, selon des modes de l'invention.
• [Fig.10] La figure 10 est une vue en coupe (X, Z) d'un ensemble de cellules du dispositif de contrôle de faisceaux RF représenté par les schémas (a) et (b), et d'un système optique représenté par le schéma (c), selon des exemples d'application de l'invention.
• [Fig.11] La figure 11 représente des étapes du procédé de fabrication du dispositif de contrôle de faisceaux RF, selon des modes de réalisation de l'invention.
• [Fig.12] La figure 12 est un graphique illustrant les performances radioélectriques atteintes par un dispositif de contrôle de faisceaux RF 300, selon des exemples de réalisation de l'invention.

Other characteristics, details and advantages of the invention will emerge on reading the description made with reference to the appended drawings given by way of example.

• [ Fig.1 ] There figure 1 is a diagram representing an optical system comprising a radio frequency beam control device, according to embodiments of the invention.
• [ Fig.2 ] There figure 2 is a diagram representing the support frame of a cell of the radio frequency beam control device according to modes of the invention.
• [ Fig.3 ] There Figure 3 is a perspective view of a cell of the radio frequency beam control device showing the support frame and an internal interconnection of the cell, according to embodiments of the invention.
• [ Fig.4 ] There Figure 4 is a perspective view of a cell of the radio frequency beam control device showing the support frame and two interconnections internal to the cell, according to embodiments of the invention.
• [ Fig.5 ] There Figure 5 represents an equivalent circuit modeled from cells of the RF beam control device, according to two diagrams (a) and (b), in modes of the invention.
• [ Fig.6 ] There Figure 6 is a perspective view of a cell of the RF beam control device showing the support frame, two internal interconnections and a tray internal to the cell, according to embodiments of the invention.
• [ Fig.7 ] There Figure 7 is a table illustrating the construction of successions of charges internal to a cell of the RF beam control device, according to modes of the invention.
• [ Fig.8 ] There figure 8 is a perspective view of a cell of the radio frequency beam control device showing the support frame, two internal interconnections and a central pillar to the cell, according to embodiments of the invention.
• [ Fig.9 ] There Figure 9 is a perspective view of a set of cells of the RF beam control device, according to embodiments of the invention.
• [ Fig.10 ] There Figure 10 is a sectional view (X, Z) of a set of cells of the RF beam control device represented by diagrams (a) and (b), and of an optical system represented by diagram (c), according to examples of application of the invention.
• [ Fig.11 ] There Figure 11 represents steps of the method of manufacturing the RF beam control device, according to embodiments of the invention.
• [ Fig.12 ] There Figure 12 is a graph illustrating the radio performance achieved by an RF beam control device 300, according to exemplary embodiments of the invention.

Identical references are used in the figures to designate identical or similar elements. For reasons of clarity, the elements shown are not to scale.

detailed description

There figure 1 represents an optical system 10 comprising a radio frequency (RF) beam control device 300, according to embodiments of the invention.

The radio frequency beam control device 300 can for example be used as a dichroic screen in an optical system 10 implemented in an antenna system (not shown) comprising a large reflector associated with several sources of radio frequency (RF) electromagnetic signals which can have very high power (for example of the order of several tens of kilowatts).

For example and without limitation, such an antenna system can be implemented in the form of an antenna mounted on board a satellite or a ground control station antenna, for space and/or scientific missions.

As used herein, the term "radio frequency beam control" (also called 'radio frequency beam manipulation') refers to various phenomena related to electromagnetic waves that can occur when an RF beam interacts with the material of an object given, such as the device 300. These phenomena include in particular the transmission, reflection, absorption, diffusion, refraction and/or diffraction of the electromagnetic wave.

Furthermore, in a use of the RF beam control device 300 as a dichroic screen, transmission screen and/or reflection screen, in an antenna system, the RF beam control device 300 can be used to transmit and /or reflect beams from distinct RF signal sources each having a distinct frequency band.

An antenna system can include different optical systems forming one or more "optical paths" and making it possible to control (in particular manipulate and/or direct) the RF signals produced by the sources positioned at different locations of the antenna system (depending on the size), towards the reflector.

Classically, these optical systems limit the design of the antenna system because they can induce significant power losses in the RF signals, and constrain the architecture of the antenna system by limiting, for example, the width of the beams (or angular aperture) produced by the RF sources. .

In the embodiment shown on the figure 1 , the optical system 10 is part of an antenna system (not shown) and comprises a first RF source 100, a second RF source 200 and an RF beam control device 300.

The two RF sources 100, 200 are configured to emit beams of electromagnetic waves in TEM mode (acronym for the Anglo-Saxon expression “Transversal Electro-Magnetic” associated with transverse electromagnetic waves) in two distinct RF frequency bands, respectively denoted λ ₁ and λ ₂ , and along two given propagation axes, denoted respectively 102 and 104. An electromagnetic wave of an emitted RF beam is further characterized by a given phase (and an associated wave front). For example, the RF sources 100, 200 can be configured to transmit in specific frequency bands so that λ ₁ corresponds to the so-called “X band”, of low frequencies, typically between 7 GHz and 8.5 GHz, and λ ₂ corresponds to the so-called “Ka band”, of high frequencies, typically between 22.5 GHz and 27 GHz.

The RF beam control device 300 is therefore defined in a reference frame (X,Y,Z). According to the embodiments of the invention, the RF beam control device 300 comprises at least two faces denoted 310 and 320. The two faces 310 and 320 are spaced apart from each other by a distance d representing the ''thickness'' of the RF beam control device 300. For example, and without limitation, the thickness d may be greater than or equal to a value substantially equal to λ ₂ /2. For example and without limitation, the thickness d can be equal to 5.5 mm. This thickness value d being very small compared to the overall size of the optical system 10, the RF beam control device 300 can have a substantially planar structure, defined in the plane (X,Y) associated with reference (X,Y ,Z) and orthogonal to the Z axis. Thus, the RF beam control device 300 generally extends in the plane (X,Y).

• la source RF 100 émet le faisceau RF selon l'axe de propagation 102 se dirigeant vers la face 310 sur laquelle le faisceau est réfléchi, et
• la source RF 200 émet le faisceau RF selon l'axe de propagation 202 se dirigeant vers la face 320. Le faisceau RF de la source RF 100 traverse alors le dispositif de contrôle de faisceaux RF 300 et donc les deux faces 310 et 320.

The RF beam control device 300 can be used as a dichroic screen to superimpose the beams from the RF sources 100, 200 on the same optical path of the antenna system. The dichroic screen 300 makes it possible, on the one hand, to reflect the beam from the low frequency RF source 100 and, on the other hand, to transmit the beam from the high frequency RF source 200. So, in example of the figure 1 , the RF beam control device 300 can be positioned between the two RF sources 100, 200, such that:

• the RF source 100 emits the RF beam along the propagation axis 102 heading towards the face 310 on which the beam is reflected, and
• the RF source 200 emits the RF beam along the propagation axis 202 heading towards the face 320. The RF beam from the RF source 100 then passes through the RF beam control device 300 and therefore the two faces 310 and 320.

As shown on the figure 1 , in certain modes of application, the RF sources 100, 200 can be of the horn type and can be associated respectively with radiation field beams 104, 204, each defined according to an opening angle denoted respectively θ ₁ and θ ₂ . The RF beam control device 300 can also be configured to modify or not the opening angle (ie the associated phase and wavefront) of the transmitted and/or reflected radiation fields noted respectively θ _{1 t} and θ2t _. For example, and in a non-limiting manner, the two RF sources 100, 200 may have a radiation field 104, 204 having the same opening angle denoted θ , before and after interaction with the RF beam control device 300. The angle θ can for example be of the order of 30°. It should be noted that the RF sources 100, 200 can also be associated with a spherical wavefront which will be transformed into a plane wavefront by another optical system for example.

In embodiments of the invention, the RF beam control device 300 can be tilted with respect to the direction of average incidence (i.e. direction of propagation 102 and 202) of the beam at the spherical wavefront of two sources RF 100 and 200, for example so as to form an arrangement of sources which does not generate masking. The average direction of incidence of the beams with the normal axis Z of the device 300 then forms an angle of incidence denoted α _i , for example substantially equal to 30°.

As a result, the projection of the radiation fields 104 and 204 of the RF sources onto the dichroic screen can vary over a very wide angular sector depending on the opening angle θ and the angle of incidence α _i of the RF sources 100 and 200. The dichroic screen is then configured to operate for highly oblique incidences, for example for angular sectors of between 15° and 45°.

In other exemplary embodiments, the optical system 10 may comprise the RF beam control device 300 and one or more RF sources 200 or 100 positioned respectively in transmission or reflection relative to the device 300, at an angle of incidence zero, such that α _i = 0°. In these embodiments, the RF beam controller 300 may be configured to transmit and/or reflect an RF beam, and modify the phase (and associated wavefront) of the electromagnetic wave of the RF beam. Such a configuration is applicable for RF 300 beam control devices used as a transmission screen (or “transmitarray” in English) and/or reflection screen (or “reflectarray” in English) to correct aberrations in multibeam optical systems. In particular, the radio frequency beam control device 300 generally extending in a plane (X,Y), can have geometric shapes and variable dimensions in the plane (X,Y) making it possible to modify the phase of the wave electromagnetic in the plane (X,Y).

For example and in a non-limiting manner, the RF sources 100, 200 may also be associated with a spherical, plane wavefront and/or comprising deformations such as aberrations generated by phase shifts. Thus, the RF beam control device 300 can be configured to transform a given wavefront (e.g. spherical) and another wavefront (e.g. planar) and/or to correct wavefront aberrations by locally modifying the phase of the RF beam in the (X,Y) plane. Furthermore, the RF beam control device 300 can be configured to differently modify the wavefront of a wave intended to be reflected (coming from the source 100) relative to the wavefront of a wave intended to be transmitted (coming from source 200). The resulting optical system 10 may include RF sources positioned manner closer to the device 300 or arranged in a manner more suited to the intended application.

In one embodiment, the two faces 310 and 320 can be parallel to each other. In such an embodiment, the two faces 310 and 320 can be surfaces defined in two dimensions in the plane (X,Y) orthogonal to the normal axis Z. Alternatively, the two faces 310 and 320 can be surfaces defined according to three dimensions in the reference frame (X,Y,Z). In these embodiments, the thickness d between the two parallel faces 310 and 320 is homogeneous along the RF beam control device 300.

Alternatively, the thickness d between the two faces 310 and 320 is inhomogeneous along the RF beam control device 300, such that the thickness d can vary along the X axis and/or along the Y axis. embodiment with variable thickness, at least one of the two faces 310 and 320 can be defined as a surface defined according to three dimensions in the reference frame (X,Y,Z). For example and in a non-limiting manner, the RF beam control device 300 may comprise a center O (not shown in the figures) positioned in the plane (X,Y) such that the thickness d varies increasing or decreasing at from this center O, along the axis X, to form a quasi-optical element, which can be a concave or convex element respectively.

The RF beam control device 300 according to the embodiments of the invention comprises a set of cells 400 arranged in the plane (X,Y), as shown in the figures 2 to 4 , 6 and 8 to 10 .

Each cell 400 of the RF beam control device 300 includes an external cell support frame 420 and one or more internal interconnections 460.

There figure 2 only shows the external support frame 420 of a cell 400, to facilitate understanding of the invention.

The support frame 420 of a cell 400 (also called "cell support frame") is inscribed in a general shape of prism (or faceted cylinder) having a main axis extending along an axis Z'. The Z' axis corresponds to a generating line of the prism and is also called "Z' prism axis". The cell support frame 420 is of length d along the axis Z'. In the example of achievement on the figure 2 (and also on the figures 3 , 4 , 6 , 8 And 9 ), the Z' axis is equivalent to the Z axis. Such a prism is a polyhedron having faces formed by parallelograms, also called “prismatic faces” and two parallel polygonal bases. The prism shape can be, for example and without limitation, a square parallelepiped called a cuboid or a hexagonal prism.

côtés de largeur ℓ, définie dans le plan (X,Y) et s'étend selon l'axe du prisme Z'. Les

faces prismatiques $P_n$

sont reliées entre elles par

arêtes latérales

parallèles entre elles et parallèles à l'axe du prisme Z'.Thus, the cell support frame 420 is inscribed in a general shape of prism which rests on a polygonal base at

sides of width ℓ, defined in the plane (X,Y) and extends along the axis of the prism Z'. THE

prismatic faces $P_{\mathrm{not}}$

are linked together by

side edges

parallel to each other and parallel to the axis of the prism Z'.

. Par exemple, si

est égal à 4, les faces prismatiques comprennent les faces $P_1,P_2,P_3$

et $P_4$

et les arêtes latérales comprennent les arêtes

et

n is an index associated with the different faces of the prism in which the cell support frame 420 is inscribed, with n $\mathrm{not}\in \left[1,\mathrm{NOT}\right]$

. For example, if

is equal to 4, the prismatic faces include the faces $P_{}$${}_1,{\mathrm{<figure-callout\; id="2"\; label="P"\; filenames="imgf0007.png"\; state="\{\{state\}\}">P</figure-callout>}}_2,P_3$

And ${\mathrm{<figure-callout\; id="4"\; label="P"\; filenames="imgf0002.png,imgf0003.png"\; state="\{\{state\}\}">P</figure-callout>}}_4$

and the side edges include the edges

And

Un élément de coin 4200-n est constitué de deux plaques rectangulaires 4200A-n et 4200B-n raccordées au niveau d'un bord 430-n coïncidant avec l'arête latérale

associée au coin du prisme, chaque plaque ayant une longueur égale à la longueur d du prisme selon l'axe d (équivalente à l'axe Z sur les figures 2 à 4, 6, 8 et 9). Chacune des deux plaques 4200A-n et 4200B-n d'un élément de coin 4200-n s'étend partiellement sur une des deux faces prismatiques $P_n$

et $P_{n+1}$

adjacentes reliées par le bord 430-n correspondant à l'arête

associée au coin du prisme. La largeur d'une plaque rectangulaire 4200A-n ou 4200B-n dans le plan (X, Y) de l'élément de coin est inférieure à la largeur ℓ d'une face prismatique.As shown on the figure 2 , the cell support frame 420 comprises, at each side edge of the prism, a corner element 4200- n arranged in the corner of the prism corresponding to the side edge

A corner element 4200- n consists of two rectangular plates 4200A- n and 4200B- n connected at an edge 430- n coinciding with the side edge

associated with the corner of the prism, each plate having a length equal to the length d of the prism along the axis d (equivalent to the Z axis on the figures 2 to 4 , 6, 8 and 9 ). Each of the two plates 4200A- n and 4200B- n of a corner element 4200- n extends partially over one of the two prismatic faces $P_{\mathrm{not}}$

And $P_{\mathrm{not}+1}$

adjacent connected by the edge 430- n corresponding to the edge

associated with the corner of the prism. The width of a rectangular plate 4200A- n or 4200B- n in the plane (X, Y) of the corner element is less than the width ℓ of a prismatic face.

« murs » 420-n coïncidant avec l'une des

faces prismatiques $P_n$

du prisme du cadre de support de cellule 420, chaque mur 420-n comprenant une discontinuité définie par une fente 440-n, s'étendant selon l'axe du prisme Z' (équivalente à l'axe Z sur les figures 2 à 4, 6, 8 et 9). Un mur 420-n comprend ainsi deux plaques rectangulaires, séparée l'une de l'autre par la fente 440-n, chacune des deux plaques appartenant à deux éléments de coin adjacents 4200-n et 4200-(n + 1) par exemple. Un mur 420- n du cadre de support de cellule 420 comprend ainsi les deux plaques rectangulaires adjacentes 4200A-n et 4200B-n qui s'étendent sur une même face prismatique $P_n$

et sont séparées de la fente 440-n.Thus, the cell support frame 420 is inscribed in the prism and includes

“walls” 420- n coinciding with one of the

prismatic faces $P_{\mathrm{not}}$

of the prism of the cell support frame 420, each wall 420- n comprising a discontinuity defined by a slot 440- n , extending along the axis of the prism Z' (equivalent to the axis Z on the figures 2 to 4 , 6 , 8 And 9 ). A wall 420- n thus comprises two rectangular plates, separated from one another by the slot 440- n , each of the two plates belonging to two adjacent corner elements 4200- n and 4200-( n + 1) for example. A wall 420- n of the cell support frame 420 thus comprises the two adjacent rectangular plates 4200A- n and 4200B- n which extend on the same prismatic face $P_{\mathrm{not}}$

and are separated from slot 440- n .

« murs » 420-n du cadre de support de cellule 420 ont une épaisseur de mur notée m. Il est à noter que, dans un dispositif de contrôle de faisceaux RF 300 comprenant deux ou plusieurs cellules 400, l'épaisseur de murs entre deux cellules 400 peut être définie comme étant égale à une valeur 2 × m. En outre, chacune des

fentes de mur 440-n a une largeur

correspondant à la distance entre les deux plaques rectangulaires 4200A-n et 4200B-n du mur qui appartiennent aux deux éléments de coin adjacents. Les

fentes 440-n continues peuvent être médianes par rapport aux murs 420-n, c'est-à-dire positionnées sensiblement au milieu du mur correspondant 420-n.THE

“walls” 420- n of the cell support frame 420 have a wall thickness denoted m. It should be noted that, in an RF beam control device 300 comprising two or more cells 400, the thickness of walls between two cells 400 can be defined as being equal to a value 2 × m . In addition, each of the

wall slots 440- n has a width

corresponding to the distance between the two rectangular plates 4200A- n and 4200B- n of the wall which belong to the two adjacent corner elements. THE

Continuous slots 440- n can be median in relation to the walls 420- n , that is to say positioned substantially in the middle of the corresponding wall 420- n .

de côtés de la base polygonale.The angle between the two plates 4200A- n and 4200B- n of a corner element 4200- n depends on the shape of the prism and in particular on the number

sides of the polygonal base.

avec le plan (X,Y) du dispositif de contrôle de faisceaux RF 300 est droit.In the example of the figure 2 , the axis of the prism Z' is parallel to the axis Z is such that the cell support frame 420 has the shape of a right prism. Thus the angle of the edges 430- n corresponding to the edges

with the plane (X,Y) of the RF 300 beam control device is straight.

Alternatively, the axis of the prism Z' can have an inclination β relative to the axis Z such that the frame 420 has the shape of an oblique prism.

murs 420-n électriquement conducteurs. Le cadre de support de cellule 420, selon les modes de réalisation de l'invention, interrompu par les

fentes sur chacune de ces faces agit comme un guide d'onde à murs parallèles 420-n permettant la propagation du faisceau à transmettre par le dispositif de contrôle de faisceaux RF 300, provenant de la seconde source RF 200.Furthermore, the cell support frame 420 can be entirely or partially metallic so as to form

420- n electrically conductive walls. The cell support frame 420, according to the embodiments of the invention, interrupted by the

slots on each of these faces acts as a waveguide with parallel walls 420- n allowing the propagation of the beam to be transmitted by the RF beam control device 300, coming from the second RF source 200.

Such cell support frames 420 interrupted by slots (or split) can thus function as a transmission screen in all frequency bands of RF signals, and can be used in particular for L, S, C, Ku and Ka bands.

. Il est à noter que la valeur maximale ℓ_max de la largeur ℓ peut être déterminée telle que ${\mathcal{l}}_{\mathit{max}}<\frac{{\lambda }_2}{2}$

.The set of cells 400 forms a periodic arrangement of waveguides whose dimensioning is small compared to the wavelength denoted λ ₂ associated with the frequency band of the beam coming from the RF source to be transmitted. In particular, the width ℓ of the cell support frame 420 can be determined such that $\mathcal{L}<\frac{{\mathrm{<figure-callout\; id="2"\; label="\lambda "\; filenames="imgf0007.png"\; state="\{\{state\}\}">\lambda </figure-callout>}}_2}{3}$

. It should be noted that the maximum value ℓ _max of the width ℓ can be determined as ${\mathcal{L}}_{\mathit{max}}<\frac{{\mathrm{<figure-callout\; id="2"\; label="\lambda "\; filenames="imgf0007.png"\; state="\{\{state\}\}">\lambda </figure-callout>}}_2}{2}$

.

murs 420-n peut être faible et être en outre ajustée, par exemple minimisée, de manière à atténuer les pertes de transmission du faisceau de la source RF 200 aux interfaces entre l'air et le guide d'onde (en entrée, face 310 et/ou en sortie, face 320), ainsi que les pertes de transmission sur une bande de fréquence et un secteur angulaire donnés qui sont proportionnelles au rapport m/ℓ. En effet, la réduction de la bande passante et la réduction du secteur angulaire peuvent être corrélées à la quantité de matière métallique formant le cadre de support de cellule 420. La minimisation l'épaisseur m peut de surcroît entraîner une minimisation de la masse totale du dispositif de contrôle de faisceaux RF 300, tout en garantissant sa rigidité. Avantageusement, l'épaisseur m des murs 420-n est inférieure à la longueur d'onde λ ₂, ce qui permet de conférer une stabilité de transmission du faisceau de la source RF 200 par rapport à la variation de l'angle d'ouverture θ en incidence sur le dispositif de contrôle de faisceaux RF 300. En particulier, l'épaisseur m des

murs 420-n selon les modes de l'invention peut être comprise entre 250µm et 500µm. L'épaisseur m des

murs 420-n peut être en outre définie en fonction des avantages et contraintes associées au processus de fabrication du dispositif de contrôle de faisceaux RF 300. Par exemple et de façon non limitative, lorsque le dispositif est fabriqué en utilisant un processus de fabrication additive (ou technique d'impression 3D), l'épaisseur de murs entre deux cellules 400 d'un dispositif de contrôle de faisceaux RF 300 peut être égale à une valeur 2 × m = 500µm. Lorsque le dispositif est fabriqué en utilisant un processus de fabrication traditionnelle, l'épaisseur de murs entre deux cellules 400 d'un dispositif de contrôle de faisceaux RF 300 peut être égale à une valeur 2 × m = 1mm. In embodiments, the thickness m of the

walls 420- n can be low and also be adjusted, for example minimized, so as to attenuate the transmission losses of the beam from the RF source 200 to the interfaces between the air and the waveguide (at the input, face 310 and/or at the output, face 320), as well as the transmission losses on a given frequency band and angular sector which are proportional to the ratio m /ℓ. Indeed, the reduction in the bandwidth and the reduction in the angular sector can be correlated to the quantity of metallic material forming the cell support frame 420. Minimizing the thickness m can also lead to a minimization of the total mass of the cell. RF 300 beam control device, while guaranteeing its rigidity. Advantageously, the thickness m of the walls 420- n is less than the wavelength λ ₂ , which makes it possible to confer stability of transmission of the beam of the RF source 200 with respect to the variation of the opening angle θ affecting the RF 300 beam control device. In particular, the thickness m of the

walls 420- n according to the modes of the invention can be between 250µm and 500µm. The thickness m of

walls 420- n can be further defined according to the advantages and constraints associated with the manufacturing process of the RF beam control device 300. For example and without limitation, when the device is manufactured using an additive manufacturing process ( or 3D printing technique), the thickness of walls between two cells 400 of an RF beam control device 300 can be equal to a value 2 × m = 500µ m . When the device is manufactured using a traditional manufacturing process, the wall thickness between two cells 400 of an RF beam control device 300 may be equal to a value 2 × m = 1 mm.

fentes 440-n traversant les murs 420-n permet en outre de simuler un matériau diélectrique et d'élargir significativement de la bande de transmission du dispositif de contrôle de faisceaux RF 300.Opening the cell support frames 420 at the level of

slots 440-n passing through the walls 420- n also make it possible to simulate a dielectric material and significantly widen the transmission band of the RF beam control device 300.

des fentes 440-n peut être comprise entre une valeur minimale notée

et une valeur maximale notée

Par exemple et sans limitation, la valeur minimale

et la valeur maximale

de largeur des fentes 440-n peuvent être définies en fonction de la largeur ℓ du cadre de support de cellule 420 et/ou de l'épaisseur m des murs 420-n, selon les équations (1) et (2) suivantes :

In particular, the width

slots 440-n can be between a minimum value noted

and a maximum value noted

For example and without limitation, the minimum value

and the maximum value

width of the slots 440-n can be defined as a function of the width ℓ of the cell support frame 420 and/or the thickness m of the walls 420- n , according to the following equations (1) and (2):

des fentes d'une même cellule 400 et/ou des fentes de l'ensemble des cellules 400 du dispositif de contrôle de faisceaux RF 300 peuvent être identiques ou variables en fonction des modes d'application de l'invention. Par exemple, et de façon non limitative, un dispositif de contrôle de faisceaux RF 300 utilisé pour transmettre et/ou dévier et/ou réfléchir un faisceau RF peut comprendre des largeurs de fentes

qui varient (de quelques micromètres par exemple) par rapport au centre O du dispositif 300 afin de moduler spatialement la phase du faisceau incident. Ainsi, le dispositif de contrôle de faisceaux radiofréquences 300 s'étendant généralement dans un plan (X,Y), peut comprendre un ensemble de plusieurs cellules 400 ayant des formes géométriques et des dimensions variables (par exemple la largeur

) dans le plan (X,Y) permettant de modifier de façon très fine (à l'échelle de la cellule) la phase (et le front d'onde associé) de l'onde électromagnétique dans le plan (X,Y).The widths

slots of the same cell 400 and/or slots of all the cells 400 of the RF beam control device 300 may be identical or variable depending on the modes of application of the invention. For example, and without limitation, an RF beam control device 300 used to transmit and/or deflect and/or reflect an RF beam may include slot widths

which vary (by a few micrometers for example) relative to the center O of the device 300 in order to spatially modulate the phase of the incident beam. Thus, the radio frequency beam control device 300 generally extending in a plane (X,Y), can comprise a set of several cells 400 having geometric shapes and variable dimensions (for example the width

) in the plane (X,Y) making it possible to modify in a very fine manner (at the cell scale) the phase (and the associated wave front) of the electromagnetic wave in the plane (X,Y).

In certain embodiments, a slot 440- n can be indented (that is to say have a variable profile along the axis of the prism Z') at the entrance (face 310) and/or at the exit (face 320) and/or along the waveguide section. These notches (not shown in the figures) and their dimensions, that is to say their length, their depth and their position, may differ depending on the slot 440- n considered in the cell 400 and/or in the plane (X ,Y).

The use of the cell support frame 420 as a waveguide in transmission makes it possible not to introduce frequency dispersion in the sections of the waveguide and to obtain very wide band responses for total transmission of a beam RF incident.

Each cell 400 of the RF beam control device 300 comprises one or more internal interconnections 460 having characteristics chosen to allow, for example, parameterization of the broadening of the frequency band of the beam coming from the first RF source 100 to be reflected and/or or the beam coming from the second RF source 200 to be transmitted.

tiges 462-n.As shown on the Figure 3 , an internal interconnection 460 of a cell 400 comprises

stems 462- n .

tiges 462-n de l'interconnexion interne 460 ont une forme sensiblement cylindrique, la longueur ℓ _t et de diamètre e_t . Par exemple et sans limitation les diamètres e_t des tiges peuvent être compris entre 400µm et 540µm. Les

tiges 462-n comprennent en outre deux extrémités notées 462-n1 et 462-n2 sur la figure 3. Pour chacune des

tiges 462-n, l'une des extrémités 462-n1 de la tige 462-n est reliée à un bord 430-n correspondant à une arête latérale

selon un « point d'attache », tandis que l'autre extrémité 462-n2 de la tige 462-n est reliée à un « point de connexion » des autres des tiges 462-n. En particulier, le point de connexion peut être positionné sensiblement au centre du cadre de support de cellule 420, dans le plan (X,Y), de sorte que l'ensemble des extrémités 462-n2 des tiges 462-n soient connectées entre elles. Les

tiges 462-n peuvent alors avoir la même longueur ℓ_t.THE

rods 462- n of the internal interconnection 460 have a substantially cylindrical shape, length ℓ _t and diameter e _t . For example and without limitation the diameters and _t of the rods can be between 400µm and 540µm. THE

rods 462-n further comprise two ends denoted 462- n 1 and 462- n 2 on the Figure 3 . For each of

rods 462- n , one of the ends 462- n 1 of the rod 462- n is connected to an edge 430- n corresponding to a lateral edge

according to an “attachment point”, while the other end 462- n 2 of the rod 462- n is connected to a “connection point” of the other rods 462- n . In particular, the connection point can be positioned substantially in the center of the cell support frame 420, in the plane (X,Y), so that all of the ends 462-n2 of the rods 462- n are connected together. . THE

rods 462- n can then have the same length ℓ _t .

murs 420-n pour les rendre entièrement solidaires entre elles. L'interconnexion interne 460 forme alors une discontinuité électrique élémentaire qui peut interagir avec les champs électriques incidents des ondes électromagnétiques TEM produites par les sources RF 100 et/ou 200 se propageant dans le cadre de support 420. Cette interaction avec les champs électriques induit la formation de courants électriques dans les tiges 462-k.Furthermore, the rods 462- k can be entirely or partially metallic so as to form an internal electrically conductive interconnection 460 which interconnects the

walls 420- n to make them fully integral with each other. The internal interconnection 460 then forms an elementary electrical discontinuity which can interact with the incident electric fields of the TEM electromagnetic waves produced by the RF sources 100 and/or 200 propagating in the support frame 420. This interaction with the electric fields induces the formation of electric currents in the rods 462- k .

(comme illustré sur la figure 3) est une interconnexion symétrique par rapport au cadre 420. Une cellule 400 comprenant une interconnexion 460 symétrique par rapport au cadre 420, est configuré pour réaliser une transmission et/ou une réflexion des ondes électromagnétiques TEM (produites par les sources RF 100 et 200) qui est invariante en polarisation. C'est-à-dire que la réponse fréquentielle de la cellule 400 permet à la polarisation des champs électriques des ondes électromagnétiques TEM incidents sur un ensemble de cellule 400, de ne pas varier après avoir été transmise ou réfléchie.The embodiment of the interconnection 460 in which the attachment points are located at the edges 430- n corresponding to the side edges

(as shown in the Figure 3 ) is an interconnection symmetrical with respect to the frame 420. A cell 400 comprising an interconnection 460 symmetrical with respect to the frame 420, is configured to carry out transmission and/or reflection of TEM electromagnetic waves (produced by the RF sources 100 and 200) which is polarization invariant. That is to say that the frequency response of the cell 400 allows the polarization of the electric fields of the TEM electromagnetic waves incident on a set of cells 400 not to vary after having been transmitted or reflected.

In embodiments where the RF beam control device 300 includes an internal interconnect 460, as illustrated by Figure 3 , the internal interconnection 460 forms a single elementary electrical discontinuity. The RF beam control device 300 is then qualified as an “order 1 device”.

est égal à 4, comme illustré par exemple sur la figure 3, une interconnexion interne 460 comprend 4 tiges pouvant être connectées au cadre de support de cellule 420 en 4 points d'attache ayant (ou non) une même distance d₁ de l'entrée de la cellule 400 (correspondant par exemple à la face 320). En particulier, la distance d ₁ peut être définie à partir de la longueur d du cadre de support de cellule 420 (par exemple d = d ₁ × 2).Furthermore in embodiments where

is equal to 4, as illustrated for example on the Figure 3 , an internal interconnection 460 comprises 4 rods which can be connected to the cell support frame 420 at 4 attachment points having (or not) the same distance d ₁ from the entrance to the cell 400 (corresponding for example to the face 320 ). In particular, the distance d ₁ can be defined from the length d of the cell support frame 420 (for example d = d ₁ × 2).

tiges 462-n forme un angle γ < 90° ou γ > 90° avec le bord 430-n d'élément de coin associé à leur point d'attache, tel que la position du point de connexion est supérieure ou inférieure à la position d ₁ des points d'attache dans le plan perpendiculaire à l'axe du prisme Z'.A rod 462- n and an edge 430- n of a corner element form an angle γ between them at the level of the end 462- n 1 of the rod 462- n (or point of attachment). For example, in certain embodiments, the rods 462- n can be defined in a plane perpendicular to the axis of the prism Z'. Advantageously, the angle γ is then equal to 90° ( γ = 90°) and the position of the connection point is equal to the position d ₁ of the attachment points. In other embodiments, each of the

rods 462- n form an angle γ < 90° or γ > 90° with the edge 430- n of the corner element associated with their point of attachment, such that the position of the connection point is greater or less than the position d ₁ of the points of attachment in the plane perpendicular to the axis of the prism Z'.

The different cells 400 of the device 300 are adjacent and connected to each other by the common cell walls 420- n . Furthermore, the internal interconnection 460 of each cell 400 is connected to the support frame of the cell 420 by the different attachment points. Such an arrangement of the cells 400 is carried out so that the cells 400 of the device 300 are integral with each other, despite the presence of the slots 440- n .

tiges 462-n. Dans les modes de réalisation où le dispositif de contrôle de faisceaux RF 300 comprend deux interconnexions internes 460, formant deux discontinuités électriques élémentaires, le dispositif de contrôle de faisceaux RF 300 est qualifié de « dispositif d'ordre 2 ».As shown on the Figure 4 , a cell 400 may comprise for example and without limitation, two internal interconnections 460, as described in relation to the embodiment of the Figure 3 . Each of these two internal interconnections 460 includes

stems 462- n . In the embodiments where the RF beam control device 300 comprises two internal interconnections 460, forming two elementary electrical discontinuities, the RF beam control device 300 is qualified as an “order 2 device”.

points d'attache situés à une même distance d ₁ par rapport à l'entrée de la cellule 400 (correspondant par exemple à la face 320), tandis qu'une deuxième interconnexion interne 460 peut être connectée au cadre de support de cellule 420 en

points d'attache situés à une même distance d ₃ par rapport la sortie de la cellule 400 (correspondant par exemple à la face 310). La distance d ₂ entre les n points d'attache respectifs des deux interconnexions internes 460 est définie à partir de la longueur d du cadre de support de cellule 420 (par exemple d = d ₁ + d ₂ + d ₃).A first internal interconnect 460 may be connected to the cell support frame 420 by

attachment points located at the same distance d ₁ relative to the entrance of the cell 400 (corresponding for example to the face 320), while a second internal interconnection 460 can be connected to the cell support frame 420 by

attachment points located at the same distance d ₃ from the outlet of cell 400 (corresponding for example to face 310). The distance d ₂ between the n respective attachment points of the two internal interconnections 460 is defined from the length d of the cell support frame 420 (for example d = d ₁ + d ₂ + d ₃ ).

Advantageously, the choice of the attachment positions of the rods 462- n determines the dimensions d ₁ and d ₃ of cells and makes it possible to influence the widening of the frequency band of the beam (particularly in transmission). Furthermore, the different dimensions d ₁ and d ₃ of all the cells 400 of the RF beam control device 300 may be identical or variable depending on the application of the invention. For example, and in a non-limiting manner, an RF beam control device 300 used to transmit and/or deflect and/or reflect an RF beam may include dimensions d ₁ and d ₃ which are variable relative to the center O of the device in order to spatially modulate the phase of the incident beam.

éléments de coin 4200-n, formant

murs 420-n interrompus chacun par une des

fentes 440-n, permettent de modéliser une impédance caractéristique $Z_1$

d'une cellule 400. Avantageusement, l'impédance caractéristique $Z_1$

d'une cellule 400 est déterminée en fonction des paramètres d et

de la cellule 400. Par exemple, une largeur de fentes

plus faible peut induire une impédance caractéristique $Z_1$

plus forte. Dans ce cas, la variation de profil des fentes (par des échancrures) peut être mise en oeuvre dans la phase de conception pour optimiser l'impédance caractéristique $Z_1$

.The RF beam control device 300 according to the invention can be manufactured from a modeling of the cells 400 in an equivalent electrical circuit (design phase). Such modeling advantageously makes it possible to optimize the quasi-optical control properties of the RF beams desired for the device 300 depending on the application of the invention. In particular, the characteristics of the cell support frame 420 consisting of

corner elements 4200- n , forming

walls 420- n each interrupted by one of the

440- n slots, make it possible to model a characteristic impedance $Z_{}$${}_1$

of a cell 400. Advantageously, the characteristic impedance $Z_{}$${}_1$

of a cell 400 is determined according to the parameters d and

of cell 400. For example, a width of slots

lower can induce a characteristic impedance $Z_{}$${}_1$

stronger. In this case, the variation of profile of the slots (by notches) can be implemented in the design phase to optimize the characteristic impedance $Z_{}$${}_1$

.

tiges 462-n), électriquement conductrice, forme une discontinuité électrique dans la cellule 400. En outre, deux interconnexions internes 460 forment un nombre de 2 discontinuités électriques successives dans la cellule 400, correspondant aux deux ensembles de

tiges 462-n. Ainsi, dans les modes de réalisation de cellule 400 représentés sur les figures 3 et 4, les tiges électriquement conductrices 462-n, encore appelées « tiges inductives », forment une succession de charges inductives notées « L » et exprimées en nH (nanoHenry), et positionnées en parallèle dans le circuit équivalent de la cellule 400.An internal interconnection 460 of a cell (the interconnection 460 comprising

rods 462- n ), electrically conductive, forms an electrical discontinuity in the cell 400. In addition, two internal interconnections 460 form a number of 2 successive electrical discontinuities in the cell 400, corresponding to the two sets of

stems 462- n . Thus, in the embodiments of cell 400 shown on the figures 3 And 4 , the electrically conductive rods 462- n , also called “inductive rods”, form a succession of inductive charges denoted “L” and expressed in nH (nanoHenry), and positioned in parallel in the equivalent circuit of cell 400.

Diagram (a) of the Figure 5 represents such an equivalent circuit modeled from cells of the RF beam control device.

The parameters relating to the electrical representation of the cell 400 in equivalent circuit depend on the position of the attachment points 462- n 1 of the rods 462- n according to the dimensions d ₁ and d ₃ .

de longueur respectivement d ₁ et d ₃ (avec par exemple d ₃ = d ₁).Thus, with reference to the example of the figure 4 and to the circuit modeled in diagram (a) of the figure 5 , the first inductive load and the second inductive load are connected respectively at the input and output of the characteristic impedance line portion $Z_{}$${}_1$

of length respectively d ₁ and d ₃ (with for example d ₃ = d ₁ ).

Advantageously, the configuration of the internal interconnections 460 symmetrically with respect to the cell support frame 420, according to attachment points at the edges 430- n , makes it possible to model equivalent electromagnetic circuits of the cell 400 which are identical (or invariant). ) with respect to the characterization according to each TE and TM polarization of the incident electric fields of the TEM waves produced by the RF sources 100 and 200.

tiges 462-n des interconnexions internes 460. En particulier, l'augmentation du diamètre e_t peut induire une diminution de l'inductance. Dans des modes de réalisation de l'invention, une augmentation du diamètre e_t par trois peut entraîner une diminution de l'inductance L d'un facteur trois. À titre d'exemple non limitatif, un diamètre e_t trop grand peut dégrader de façon significative la largeur de la bande de transmission pour les fréquences élevées (de la source 200). Dans ce cas, une étape d'optimisation du ou des diamètres e_t peut être mis en oeuvre dans la phase de conception du dispositif 300 pour optimiser en parallèle la ou les valeurs d'inductances L. Par exemple, il est possible d'obtenir des inductances L jusqu'à une valeur limite L_limit déterminée à partir d'une valeur minimale du diamètre e_t des tiges.The inductances L of the successive inductive loads modeled by the equivalent circuit can also depend on the diameter(s) _and of the

rods 462- n of internal interconnections 460. In particular, increasing the diameter e _t can induce a decrease in inductance. In embodiments of the invention, an increase in diameter e _t by three can result in a decrease in inductance L by a factor of three. As a non-limiting example, a diameter that _is too large can significantly degrade the width of the transmission band for high frequencies (of the source 200). In this case, a step of optimizing the diameter(s) e _t can be implemented in the design phase of the device 300 to optimize in parallel the inductance value(s) L. For example, it is possible to obtain inductances L up to a limit value L _limit determined from a minimum value of the diameter and _t of the rods.

tiges 462-n. En particulier, une forte variation de cet angle d'inclinaison γ par rapport à une valeur de 90° peut induire une augmentation de l'inductance d'une part tandis que la distribution des positions de cette inductance est dissymétrique sur le circuit équivalent. Il peut en résulter des effets sur les propriétés de réflexion et de transmission du dispositif 300. Par exemple, la variation de l'angle γ peut être liée à l'élargissement de la bande de fonctionnement du dispositif 300, avec une dégradation simultanée du niveau de réflexion.The inductances L can also depend on the angle of inclination γ of the

stems 462- n . In particular, a strong variation of this inclination angle γ relative to a value of 90° can induce an increase in the inductance on the one hand while the distribution of the positions of this inductance is asymmetrical on the equivalent circuit. This may result in effects on the reflection and transmission properties of the device 300. For example, the variation of the angle γ may be linked to the widening of the operating band of the device 300, with a simultaneous degradation of the level reflection.

est égal à 4.There Figure 6 represents a perspective view of a cell 400 comprising two internal interconnections 460 and a plate 470 internal to the cell support frame 420, according to modes of the invention where the number

is equal to 4.

The plate 470 internal to the cell support frame 420 can extend in a plane orthogonal to the axis of the prism Z' and be arranged (or positioned) substantially in the middle of the two internal interconnections 460.

côtés du cadre de support 420. Par exemple et sans limitation, la base polygonale du cadre de support de cellule 420 peut avoir une forme carrée ( $N=4$

) de côté de longueur ℓ et le plateau interne 470 peut avoir une forme carrée de côté de longueur ℓ_c, tel que $${\mathcal{l}}_c=\mathcal{l}-\epsilon \mathrm{et}\epsilon \ll \mathcal{l}.$$

An internal plate 470 can be a metal structure having a thickness e _c and a shape adapted to the shape of the polygonal base of

sides of the support frame 420. For example and without limitation, the polygonal base of the cell support frame 420 may have a square shape ( $\mathrm{NOT}=4$

) with a side of length ℓ and the internal plate 470 can have a square shape with a side of length ℓ _c , such that $${\mathcal{L}}_{\mathrm{vs}}=\mathcal{L}-\epsilon \mathrm{And}\epsilon \ll \mathcal{L}.$$

In particular, the internal plate 470 can be designed to approach the cell support frame 420, according to a spacing (or length) ε ≠ 0, but not be metallically connected by the sides of the internal plate 470 to the support frame of cell 420. In some embodiments, the internal plate 470 may be held within the cell support frame 420 by dielectric support means. Alternatively, the internal plate 470 can be held by a dielectric or metallic connection to the two internal interconnections 460. For example, this dielectric or metallic connection to the two internal interconnections can be a central pillar extending along the axis of the prism Z' and comprising an upper end and a lower end connected to the two internal interconnections 460, the capacitive plate then being arranged substantially in the middle of the central pillar between the two internal interconnections 460.

A metallic and electrically conductive internal plate 470 can induce a capacitive charge denoted “C” expressed in fF (femtoFarad), forming an elementary electrical discontinuity in the cell 400. Such an internal plate 470 in the cell support frame 420 corresponding more generally to a tray called a “capacitive tray”.

According to the embodiments where the RF beam control device 300 comprises two internal interconnections 460 (inductive rods) and an internal plate 470 (capacitive plate), forming three elementary electrical discontinuities as described with reference to the example in the Figure 6 , the RF beam control device 300 is then qualified as an “order 3 device”.

The equivalent electrical circuit modeling of cell 400 as represented on the Figure 6 is shown in diagram (b) of the Figure 5 . This equivalent electrical circuit modeling represents a succession of charges: inductive (L), capacitive (C) and inductive (L). Each of the loads (capacitive and inductive) in the modeled equivalent circuit are designed to achieve a frequency response of the RF beam control device 300 of the high-pass filter type. In particular, such a structure of the cells 400 makes it possible to obtain a significant increase in the rejection of the low frequency band. For example, at 8.5 GHz, the X-band rejection can reach 32 dB when the bandwidth is Ka-band.

The capacitance C of the capacitive load, for example modeled in the equivalent circuit in Figure 5(b) , can therefore depend on the different dimensions of the capacitive plate. In particular, increasing the thickness e _c can increase the capacity of the circuit. In embodiments of the invention, an increase in the diameter e _c may imply an increase in the capacitance C. For example, a diameter e _c that is too large can significantly degrade the width of the transmission band for high frequencies (from source 200).

The capacitive plate can have any shape adapted to the shape of the polygonal base of the cell support frame 420.

In embodiments, to achieve the same performance as for a capacitive plate having a shape equivalent to the shape of the polygonal base, the cell 400 may comprise a cell support frame 420 having a thickness m _c of wall 420- n greater locally in the plane of the capacitive plate, compared to the wall thickness m 420- n . A local thickening of the walls of the frame 420 up to a spacing ε of the shape of the capacitive plate makes it possible to obtain performances similar to the previous case, in which there is no local thickening of the walls 420- n . Advantageously, this alternative can be used if large values of C are to be implemented.

Advantageously, depending on the intended application of the invention, the design of the RF beam control device 300 may include a step of determining the order x of the device in order to optimize the parameterization associated with RF beam control ( for example the widening of the frequency band of the beam coming from the first RF source 100 to be reflected and/or of the beam coming from the second RF source 200 to be transmitted). In particular, during the modeling of the cells 400 in an equivalent circuit, the determination of the order x of the device can include the evaluation of the successions of inductive or successions of inductive and capacitive loads, as shown in the table in Figure 7 .

The RF beam control device 300 can be manufactured using different techniques, such as a 3D printing technique, also called additive manufacturing. Advantageously, the use of a 3D printing technique makes it possible to obtain a uniform RF beam control device 300, comprising no dielectric and entirely metallic, using an electrically conductive material such as aluminum or titanium. For example. The electrically conductive material such as titanium can then be covered with another electrically conductive material such as silver for example in order to reduce ohmic losses. Additionally, the 3D manufacturing technique induces Passive Intermodulation Products (or PIPs) generated at lower intensity so that the RF beam control device 300 can withstand higher powers from the RF signal sources.

In some embodiments of the invention, depending on the manufacturing technique used to manufacture the RF beam control device 300, additional internal elements may be added to the cell support frame 420, such as a central pillar for example .

est égal à 4.There figure 8 represents a perspective view of a cell 400 comprising two internal interconnections 460 and a central pillar 480 arranged in the center of the cell support frame 420, according to an exemplary embodiment of the invention in which the number

is equal to 4.

Although not limited to such embodiments, the use of a central pillar 480 is particularly advantageous in embodiments where the manufacturing technique is a 3D printing technique.

murs 420-n. En outre, le pilier central 480 est agencé (ou positionné) sensiblement au centre du cadre de support de cellule 420 (i.e. centre du cadre dans le plan orthogonal à l'axe du prisme Z'). Au moins l'une des deux extrémités 482-1 et 482-2 peut être positionnée à l'extérieur de la cellule 400. Dans le cas où les deux extrémités 482-1 et 482-2 sont positionnées à l'extérieur de la cellule 400, la relation d_z ≤ d est vérifiée. Dans le cas où une seule des deux extrémités 482-1 ou 482-2 est positionnée à l'extérieur de la cellule 400, la relation d_z ≤ d ou d_z > d peut être vérifiée. Alternativement, les deux extrémités 482-1 et 482-2 de l'interconnexion 480 peuvent être positionnées à l'intérieur de la cellule 400 tel que d_z ≤ d. The central pillar 480 may have a substantially cylindrical shape, with a diameter denoted e _p and a length d _p , and comprise two ends denoted 482-1 and 482-2 and called “upper end 482-1” and “lower end 482-2 ". The central pillar 480 extends along the axis of the prism Z' (in the direction of its length) and is thus parallel to the general orientation of the

walls 420- n . In addition, the central pillar 480 is arranged (or positioned) substantially in the center of the cell support frame 420 (ie center of the frame in the plane orthogonal to the axis of the prism Z'). At at least one of the two ends 482-1 and 482-2 can be positioned outside the cell 400. In the case where the two ends 482-1 and 482-2 are positioned outside the cell 400 , the relation d _z ≤ d is verified. In the case where only one of the two ends 482-1 or 482-2 is positioned outside the cell 400, the relationship d _z ≤ d or d _z > d can be verified. Alternatively, the two ends 482-1 and 482-2 of the interconnection 480 can be positioned inside the cell 400 such that d _z ≤ d.

Furthermore, as shown in the figure 8 , each of the two ends 482-1 or 482-2 of the central pillar 480 is connected to one of the two connection points formed by the ends 462- n 2 of the rods 462- n of each of the two internal interconnections 460. For example, the upper end 482-1 can be connected to the rod connection point of one of said internal interconnections 460, and the lower end 482-2 can be connected to the rod connection point of another internal interconnection 460. Both interconnections internal 460 and the central pillar 480 thus form a single interconnection of the cell support frame 420.

This unique integral interconnection allows great mechanical rigidity of the rods 462- n , and more generally of the cells 400. Such rigidity generates in particular mechanical stability of the device 300 over time, and thus of these quasi-optical control properties of beams. RF, in applications of the invention using very high power sources. Furthermore, the central pillar 480 facilitates the manufacture of the internal interconnections 460 and therefore of the cells 400 with split faces, in particular when the RF beam control device 300 is manufactured using a 3D printing technique.

). Par exemple, l'angle γ peut être égal à un angle de 90°±45° (γ = 45° et/ ou 135°), dans les modes de réalisation utilisant une technique d'impression 3D, et la distance d ₂ peut être supérieure à d_p, comme illustré sur la figure 8. L'homme du métier comprendra aisément que ces exemples d'angle γ et de distance d ₂ sont donnés à titre d'exemples non limitatifs et que l'invention couvre toute combinaison d'angle γ et de distance d ₂ qui peut être mise en oeuvre en fonction des propriétés désirées pour le dispositif 300, telle que par exemple les propriétés de contrôle quasi-optique des faisceaux RF, de stabilité et de rigidité, de facilité de fabrication, etc. L'unique interconnexion 460 interconnectant les

murs 420-n pour les rendre solidaires permet d'obtenir une structure du dispositif de contrôle de faisceaux RF 300 ayant des propriétés de solidité très importantes, au moyen notamment du pilier central 480, des points d'attache au niveau des bords 430-n, et de l'angle γ des tiges 462-n.According to certain embodiments, the distance d ₂ between the two sets of attachment points of the rods 462- n formed by the two internal interconnections 460 may be greater, less than or equal to the length d _p of the central pillar 480. In particular , the distance d _p can depend on the angle γ . For example, in certain embodiments, the two sets of rods 462- n can be defined in a plane perpendicular to the axis of the prism Z', as illustrated by the example of internal interconnections 460 of the figure 4 . The angle γ is then equal to 90° ( γ = 90°) and the distance d ₂ is equal to d _p . In other embodiments, each of the rods 462- n form an angle γ < 90° or an angle γ > 90° with the edge 430- n of the corner element associated with their point of attachment (which coincides with a lateral edge

). For example, the angle γ can be equal to an angle of 90°±45° ( γ = 45° and / or 135°), in the embodiments using a 3D printing technique, and the distance d ₂ can be greater than d _p , as illustrated in the figure 8 . Those skilled in the art will easily understand that these examples of angle γ and distance d ₂ are given as non-limiting examples and that the invention covers any combination of angle γ and distance d ₂ which can be implemented. implemented according to the desired properties for the device 300, such as for example the properties of quasi-optical control of the RF beams, stability and rigidity, ease of manufacturing, etc. The unique 460 interconnect interconnecting the

walls 420- n to make them integral makes it possible to obtain a structure of the RF beam control device 300 having very important solidity properties, in particular by means of the central pillar 480, the attachment points at the edges 430- n , and the angle γ of the rods 462- n .

In a non-limiting embodiment, the diameter e _p of the central pillar 480 can be equal to 400 μm. The central pillar 462 has substantially no effect on the quasi-optical control properties of RF beams of the device 300. Indeed, the propagation is orthogonal to the pillar of the incident electric fields of the TEM electromagnetic waves (produced by the RF sources 200 by example) which propagate in the waveguide formed by the cell support frame 420. This orthogonal propagation does not induce the formation of electric current in the central pillar 480, the diameter e _p being negligible compared to the bands of RF frequencies. As a result, the impact of the central pillar 480 in the equivalent circuit modeling is significantly negligible. For example, the unique interconnection of the figure 8 can be substantially modeled by the two internal interconnections 460 represented on the Figure 4 , that is to say as a succession of two inductive charges (L). Diagram (a) of the Figure 5 therefore represents the equivalent circuit modeled from such cells of the RF beam control device 300.

The impact of the central pillar 480 being negligible in equivalent circuit modeling, those skilled in the art will easily understand that such a particular interconnection configuration, comprising one or more central pillars 480, can be adapted to all device designs. 'order x, such that x ≥ 2 according to the determination of the number and nature of the successions of charges (inductive, or inductive and capacitive) represented as an example on the Figure 7 .

Advantageously, depending on the manufacturing technique of the RF beam control device 300, the addition of one or more central pillars 480 can facilitate the manufacturing of one or more plates 470 internal to the cell support frame 420 In particular, a capacitive plate can be formed by a local widening of the diameter e _p over a small portion e _c of the length d _p of a central pillar 480 of a single interconnection. The local enlargement of the diameter e _p can also have a shape equivalent to the shape of the polygonal base along a side length ℓ _c .

est égal à 6.There Figure 9 represents a perspective view of several cells 400 of the RF beam control device 300, in an embodiment where the number

is equal to 6.

est égal à 6, le dispositif de contrôle de faisceaux RF 300 présente des sections hexagonales de guides d'onde en transmission.In such an embodiment where the number

is equal to 6, the RF beam control device 300 has hexagonal sections of waveguides in transmission.

augmente, le dispositif de contrôle de faisceaux RF 300 peut présenter de meilleures propriétés d'invariance en polarisation et de stabilité de transmission par rapport à la variation de l'angle d'ouverture l'onde électromagnétique injecté en incidence. Une telle augmentation induit une plus importante solidité de la structure.Advantageously, if the number

increases, the RF beam control device 300 can exhibit better properties of polarization invariance and transmission stability with respect to the variation of the opening angle of the electromagnetic wave injected into incidence. Such an increase induces greater solidity of the structure.

diminue, le dispositif de contrôle de faisceaux RF 300 peut présenter des avantages de fabrication puisque la structure présente moins de matière.Alternatively, if the number

decreases, the RF beam control device 300 may have manufacturing advantages since the structure has less material.

In the embodiments of the cell support frame 420 shown on the figures 2 to 5 , 8 And 9 , the axis of the prism Z' is parallel to the axis Z. In addition, the axis of the prism Z' can have an inclination β with respect to the axis Z.

There Figure 10 represents views in a plane (X,Z) of several cells 400 of the RF beam control device 300 according to two modes of the invention represented by diagrams (a) and (b), in which the walls 420- n , 440-n slots (and furthermore the central pillars 480) of the cell support frame 420 are oriented at an inclination β relative to the Z axis.

In embodiments of the optical system 10 on the figure 1 , the angle of inclination β of the cells 400 is for example between 0° and α _i relative to the axis Z. Indeed, the axis of the prism Z' of the cells 400 of the RF beam control device 300 , inclined with respect to the direction of average incidence of the beam at the spherical wavefront of two RF sources 100, 200, according to an angle of incidence denoted α _i , can be composed of cells 400 of inclination angle β = α _i as illustrated schematically in diagrams (a), (b) and (c) of the Figure 10 , to increase the robustness of the quasi-optical properties of the structure with respect to the angular sector, that is to say the angle of incidence and the opening angle θ of the beams.

In particular, such a concept of inclination of the cells 400 allows the doubling of this angular sector (±10° around α _i = 30°) compared to the solutions of the state of the art.

It should be noted that this β inclination of the cells 400 has no significant influence on the equivalent electrical circuit modeling. However, this inclination can induce an increase in the thickness of the 420- n walls.

Diagram (a) of the Figure 10 represents a single interconnection (comprising two internal interconnections 460 and a central pillar 480) defining a succession of two inductive loads. In this diagram, the entry face 310 is in the plane (X,Y), while the exit face 320 has a beveled (or stepped) structure perpendicular to the axis of the prism Z' defining the inclination of the frames cell support 420.

des fentes 440-n en induisant un décalage de la largeur de bande d'impédance pour l'incidence des polarisations TE et TM (la différence de largeur relative ne peut donc pas être importante).The geometry of the input 310 and output 320 faces could induce an asymmetry which could deteriorate the phase balance of the beams to be controlled. Such an imbalance can be avoided or compensated for by variations in width

slots 440- n by inducing a shift in the impedance bandwidth for the incidence of the TE and TM polarizations (the difference in relative width cannot therefore be significant).

Advantageously, the inlet 310 and outlet 320 faces can each have a beveled (or stepped) structure perpendicular to the axis of the prism Z' defining the inclination of the cell support frames 420. This face configuration can for example provide better theoretical RF beam transmission performance to the device 300.

Diagram (b) of the Figure 10 corresponds to a single interconnection (comprising two internal interconnections 460 and a central pillar 480 widened in the center to form an internal plate 470) defining a succession of charges: inductive, capacitive and inductive. In this diagram, the input 310 and output 320 faces are parallel to each other and to the plane (X,Y).

Those skilled in the art will easily understand that the input 310 and output 320 faces of the devices 300, represented in diagrams (a) and (b) of the Figure 10 , are non-limiting examples and that the inlet 310 and/or outlet 320 faces of the devices 300 may alternatively comprise a staircase structure, and/or that the inlet 310 and/or outlet 320 faces of the devices 300 can be parallel to the plane (X,Y). In particular, the spectral response of a device 300 comprising at least one face comprising a staircase structure can be optimal compared to the embodiments of the optical system 10 of the figure 1 . Indeed, such staircase structures are adapted to oblique incident waves allowing propagation without discontinuity in the waveguides formed by the cell support frames 420.

des fentes 440-n.However, such staircase structures can induce variations in wall thickness m, as illustrated in diagram (a) of the Figure 10 . Thus a minimum wall thickness m _min can be defined as a function of the manufacturing process (for example m _min = 250µ m ), which can make it possible to double the wall thickness m = 500µ m within a cell 400. This variation in wall thickness between m _min and m can be incremental or progressive. It should be noted that this doubling of wall thickness can induce modifications in the quasi-optical operating properties of the device 300. Such modifications can be compensated for by variations (in particular an increase) in the width

slots 440- n .

des guides d'onde. Notamment, l'impédance caractéristique $Z_1$

peut rester sensiblement stable pour des inclinaisons β faibles, par exemple pour des valeurs de β inférieures ou égales à 30° (β ≤ 30°). Inversement, l'impédance caractéristique $Z_1$

peut être modifiée significativement pour des inclinaisons β fortes, par exemple pour des valeurs de β strictement supérieures à 30° (β > 30°).The equivalent circuit modeling of the devices, shown in diagrams (a) and (b) of the Figure 10 , can take into account the inclination β in the variation of the characteristic impedance $Z_{}$${}_1$

waveguides. Notably, characteristic impedance $Z_{}$${}_1$

can remain substantially stable for low β inclinations, for example for values of β less than or equal to 30° ( β ≤ 30°). Conversely, the characteristic impedance $Z_{}$${}_1$

can be significantly modified for strong β inclinations, for example for values of β strictly greater than 30° ( β > 30°).

Advantageously, the implementation of the inclination β of the cells 400 as well as the modularity of structures (in stairs or parallel to the faces) of the entry faces 310 and/or exit faces 320 of the devices 300 can be facilitated by the use of 3D printing techniques. In particular, the RF 300 beam control device produced by 3D printing has a good surface condition. Thus, the inclination of the cells 400 and the use of additive manufacturing also makes it possible to halve the insertion losses of the beams of the RF source 200 to be transmitted compared to the reference of the state of the art.

It should be noted that diagram (b) of the Figure 10 illustrates cells 400 comprising an internal plate 470 corresponding to a local widening of the diameter e _p , over a portion e _c of the length d _p of a central pillar 480. In this diagram, the internal plates 470 integrate certain manufacturing constraints additives. The internal plates 470 and the central pillar 462 then form a structure comprising two pyramidal shapes (on a slope of 45° for example) which do not modify the performance of the interconnection 460.

There Figure 11 is a flowchart representing two steps of a manufacturing process according to embodiments of the RF beam control device 300 in which the cells 400 have a tilt angle β . There Figure 11 also shows a perspective view of a set of cells of the RF beam control device 300, illustrated by diagrams (a) and (b), during the two stages of the manufacturing process.

In step 1102, a material is deposited by additive manufacturing as a priority, along the axis of the prism Z' having an angle of inclination β with the axis Z, to form stacked metal layers.

In step 1104, the structure formed by the stacked metal layers is cut at the input face 310 of the RF beam control device 300. For example, the face 310 can be defined by a plane parallel to the plane (X,Y) of the RF beam control device 300.

As illustrated by diagram (a) of the Figure 10 , this method can induce a non-symmetrical discontinuity inducing small disturbances in the frequency response of the RF beam control device 300. However, these disturbances can be compensated by a reduction in the inclination of the cells 400 relative to the direction of average incidence (typically β = 20° < α _i = 30°).

There Figure 12 is a graph showing an example of radio performance achieved by the RF beam control device 300 used as a dichroic display.

The graph of the Figure 12 shows the evolution of the transmission gain and the return reflection losses as a function of frequency, according to the two polarizations TE and TM. The graph notably highlights a wide band of Ka and X frequencies of the incident electromagnetic wave, invariant with respect to the polarization.

The invention is not limited to the embodiments described above by way of non-limiting example. It encompasses all the alternative embodiments which could be envisaged by those skilled in the art. In particular, those skilled in the art will understand that the invention is not limited to the cell, frame and interconnection geometries described by way of non-limiting example.

Claims (16)

Radio frequency beam control device (300), comprising a set of at least one cell (400), said cell (400) comprising a support frame (420) and at least one interconnection (460) internal to said support frame ( 420), said radio frequency beams being TEM electromagnetic waves having a given polarization, characterized in that said support frame (420) is inscribed in a prism, having a given axis Z', said prism comprising

faces $P_{\mathrm{not}}$

linked together by

edges

oriented along the axis of the prism Z', said support frame (420) comprising

corner elements (420- n ), each corner element having an edge (430- n ) coinciding with one of said edges of the prism, the corner elements being arranged so that the support frame presents, on each face of the prism, a slot (440- n ) extending along the axis of the prism Z', said support frame (420) being interrupted by said slots (440- n ); And in that each internal interconnection (460) comprises

inductive rods (462- n ) each comprising two ends (462- n 1, 462- n 2), the inductive rods (462- n) each having a first end (462- n 1) connected to one of said edges (430- n ) of the support frame (420), the second ends (462- n 2) of the inductive rods (462- n ) being connected together at a rod connection point, said rod connection point being positioned substantially in the center of said support frame (420) in a plane orthogonal to the axis of the prism Z', each cell (400) being configured to carry out polarization-invariant transmission and/or reflection of radio frequency beams of said TEM electromagnetic waves. Radio frequency beam control device (300) according to claim 1, wherein the cell (400) comprises at least two internal interconnections (460), and wherein the cell (400) further comprises at least one capacitive plate (470 ) internal to said support frame (420) extending in a plane orthogonal to the axis of the prism Z', said at least one capacitive plate (470) being arranged between said two internal interconnections (460). Radio frequency beam control device (300), according to one of the preceding claims, in which a cell (400) comprises at least two internal interconnections (460), and in which the cell (400) further comprises at least one pillar central (480) extending along the axis of the prism Z' and being arranged substantially at the center of said support frame (420), said central pillar (480) comprising an upper end (482-1) connected to the rod connection point of one of said internal interconnections (460), and a lower end (482- 2) connected to the rod connection point of another internal interconnection (460). Radio frequency beam control device (300) according to claim 2, wherein said at least one capacitive plate (470) is connected to the support frame (420) by at least one central pillar (480) extending along the axis of the prism Z' and comprising an upper end and a lower end, the capacitive plate (470) being arranged substantially in the middle of the central pillar (480). Radio frequency beam control device (300) according to claim 2, wherein said at least one capacitive plate (470) is held inside the support frame (420) by means of a dielectric support. Radio frequency beam control device (300), according to one of claims 1 to 4, wherein said support frame (420) and said at least one internal interconnection (460), forming each cell, are electrically conductive and constituted by a single electrically conductive material. Radio frequency beam control device (300), according to one of the preceding claims, in which the number

is equal to 4 and said support frame (420) having the shape of a square parallelepiped, or in which the number

is equal to 6 and said support frame (420) having a hexagonal prism shape. Radio frequency beam control device (300), according to one of the preceding claims, in which the radio frequency beam control device (300) is defined in a reference frame (X,Y,Z), the radio frequency beam control device (300) generally extending in a plane (X,Y), and in which the axis of the prism Z' is parallel to said axis Z, said support frame (420) having the shape of a right prism. Device for controlling radio frequency beams (300), according to one of claims 1 to 7, in which the device for controlling radio frequency beams (300) is defined in a reference frame (X,Y,Z), the device for controlling radio frequency beams (300) generally extending in a plane (X,Y), the axis of the prism Z' having an inclination β with respect to the axis Z, and said support frame (420) having a prism shape oblique. Radio frequency beam control device (300), according to one of the preceding claims, in which the inductive rods (462- n ) and the edges (430-n) of said support frame (420) form an angle γ between 45° and 90°, and/or between 90° and 135°. Radio frequency beam control device (300), according to one of the preceding claims, in which the radio frequency beam control device (300) is defined in a reference frame (X,Y,Z), the radio frequency beam control device (300) generally extending in a plane (X,Y), the device comprising a set of several cells (400) having geometric shapes and variable dimensions in the plane (X,Y). Optical system (10) comprising at least a first source (100) of radio frequency signals configured to emit a radio frequency beam of frequency band λ ₁ in a given direction of propagation (102) and an RF beam control device (300) according to one of claims 1 to 11, said radio frequency beam control device (300) being configured to reflect and/or transmit the radio frequency beam in said given direction of propagation (102) and said frequency band λ ₁ . Optical system (10) according to claim 12, in which the optical system (10) comprises at least two sources of radio frequency signals, said sources comprising a second source (200) configured to emit a radio frequency beam of frequency band λ ₂ according to a given direction of propagation (202), and in which the radio frequency beam control device (300) is defined in a reference frame (X,Y,Z), the radio frequency beam control device (300) generally extending in a plane (X,Y), the control device being configured to reflect the radio frequency signals of frequency band λ ₁ and transmit the radio frequency signals of frequency band λ ₂ , said radio frequency beam control device (300) being positioned between said sources (100, 200), the Z axis having an angle of incidence α _i relative to said sources (100, 200), for example α _i = 30°. Optical system (10) according to claim 12, wherein the radio frequency beam emitted by said first source (100) is a TEM electromagnetic wave having a given phase, and wherein the radio frequency beam control device (300) is defined in a mark (X,Y,Z), the radiofrequency beam control device (300) generally extending in a plane (X,Y), the control device comprising a set of several cells (400), said radio frequency beam control device (300) being configured to modify said phase in the plane (X,Y). Method of manufacturing the radio frequency beam control device (300) according to one of claims 1 to 11, characterized in that the device is entirely metallic, and the manufacturing method uses at least one 3D printing technique. Method of manufacturing the radio frequency beam control device (300), according to claims 9 and 15, said device (300) comprising two faces defined in the plane (X,Y), and in which the method comprises a first step (1102 ) of depositing layers of metal stacked in the direction of said inclination β, then a second step (1104) of cutting at least one of the two faces of the device (300).

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