Membrane for antenna

Abstract

The invention relates to a deployable membrane for an antenna (2) capable of taking a first folded state (32) in which the size of the membrane is reduced and a second deployed state (31) in which the membrane has an optimal geometry for the antenna. According to the invention, the membrane comprises at least one arm secured to the membrane, said arm comprising a shape memory material. Figure for abstract: Fig. 3

Description

Title of the invention: Membrane for antenna Technical field of the invention

[0001] The present invention relates generally to antennas, and in particular to radiofrequency antennas. Technical background

[0002] An antenna is a device for radiating (transmitter) or capturing (receiver) electromagnetic waves. The antenna is a key element in a radio system. It is characterized in particular by its efficiency, gain, and radiation pattern. These parameters directly influence the quality and range performance of the system.

[0003] In microwave frequencies, we know in particular reflector antennas. These antennas can in particular use flat or parabolic reflectors.

[0004] The parabolic antenna is best known for its use in satellite television or for space applications.

[0005] The parabolic antenna conventionally comprises a parabolic reflector which is responsible for concentrating the waves received or emitted towards a source of the antenna. Conventionally the source is placed at the focus of the parabola.

[0006] The source may be a transmitter in the case of an antenna used for transmission or a receiver in the case of an antenna used for reception.

[0007] There are also planar antennas comprising a radiating element in the form of a flat sheet which can take the form of a rectangle, a square or a strip.

[0008] In the space field, the weight and size of the antenna are essential, particularly during the launch of a satellite, a space vehicle or any other object. Thus, deployable antennas have been developed. Some use rigid folding petals that can be deployed to form a parabola or a planar antenna. However, this type of antenna has the disadvantages of being heavy and complex to manufacture and implement (which leads to increased risks of failure). Other deployable antenna technologies use a foldable metal network or a metallized plastic film.

[0009] The disadvantages of these technologies remain the weight and the risk of failure due to the complexity of their operating mode. Summary of the invention

[0010] Based on this problem, the present invention therefore has the task of developing a new technology for producing antennas that are lighter. Another objective of the present invention is to obtain antennas that are less bulky. Another objective of the present invention is to obtain antennas that are less expensive and simpler to implement. Another objective of the present invention is to produce antennas that are more reliable.

[0011] The invention relates in particular to an elastic membrane for an antenna, the membrane comprising an entanglement of one or more non-woven conductive thread(s) secured in a matrix of an elastic material. In the context of the present invention, entanglement means any grouping or tangling or interlacing of at least one thread(s).

[0012] In the context of the present invention, wire is understood to mean an element having a shape extending longitudinally. For example, a ribbon (or a long rectangle) must also be considered as a wire within the meaning of the present invention. A wire can have any diameter, even a large one, such as a rope or a cylinder.

[0013] Advantageously, at least one of the conductive wire(s) of the entanglement is a wire comprising a first strand of an electrically conductive material and a second strand of a deformable thermoformable material, said first and second strands being interlaced. Of course, the thermoformable material may be rigid or even elastic.

[0014] Advantageously, the thermoformable material is a silicone.

[0015] Advantageously, the matrix is ​​obtained from the thermoformable material of the second strand.

[0016] Advantageously, the interlacing of the first and second strands is obtained by wrapping. Of course, the interlacing can be obtained by any other technique for binding strands or threads such as for example weaving, knitting or by melting or at least partial fusion of at least one of the strands. According to an embodiment of the present invention, the membrane is a deployable membrane for an antenna which can take a first folded state (or even folded or even compressed or even crumpled or even with reduced bulk) in which the bulk of the membrane is reduced and a second deployed state (or even unfolded or even decompressed or even uncreased or even with greater bulk) in which the membrane has an optimal geometry for the antenna.

[0017] According to the invention, the membrane may comprise at least one arm secured to the membrane, said arm comprising a shape memory material.

[0018] According to one embodiment of the invention, at least one of the arm(s) comprises a wire comprising a first strand made of a shape memory material and a second strand made of an electrically conductive material, said second strand being wound around the first strand.

[0019] According to at least one embodiment of the invention, at least one of the arm(s) comprises a wire made of an alloy of a shape memory material and an electrically conductive material.

[0020] The invention also relates to a reflector antenna whose reflector comprises a membrane as previously described.

[0021] The invention also relates to a planar antenna comprising a radiating panel which itself comprises a membrane as previously described.

[0022] The invention also relates to a deployable membrane for an antenna which can take a first folded state (or even folded or even compressed or even crumpled or even with reduced bulk) in which the bulk of the membrane is reduced and a second deployed state (or even unfolded or even decompressed or even uncreased or even with greater bulk) in which the membrane has an optimal geometry for the antenna.

[0023] According to the invention, the membrane may comprise at least one arm secured to the membrane, said arm comprising a shape memory material. In the context of the present invention, the term “secured” means a direct or indirect connection (for example connected via another element). In the context of the present invention, the term “shape memory material” means any material which, once deformed, is capable of at least partially returning to a shape, size, geometry or configuration under certain conditions. A shape reversible material or a material in a reversible state is also to be considered as a shape memory material according to the invention.

[0024] Thus, according to one embodiment of the invention, the deployment of the membrane can be activated by an internal action or an external action, for example thermal heating.

[0025] Advantageously, at least one of the arm(s) comprises a wire comprising a first strand made of a shape memory material and a second strand made of an electrically conductive material, said second strand being wound around the first strand.

[0026] According to one embodiment of the invention, at least one arm comprises an assembly of at least two constituents: one constituent based on a material with a reversible shape state and another constituent based on another material which is electrically conductive. For example, if the arm is a wire, this may be the assembly of wires fulfilling these functions.

[0027] Advantageously, at least one of the arm(s) comprises a wire made of an alloy of a shape memory material and an electrically conductive material. According to one embodiment of the invention, the electrically conductive material is such that it allows thermal heating due to its physicochemical properties.

[0028] Advantageously, the deployable membrane has a parabola shape in the deployed state and in that it comprises several arms secured to the internal surface of the parabola and extending from the center of the parabola towards the periphery of the parabola when in the deployed state.

[0029] Advantageously, the deployable membrane has a strip shape in the deployed state and in that it comprises at least one arm secured in a parallel manner to the strip when in the deployed state.

[0030] Advantageously, the membrane is an elastic membrane.

[0031] According to one embodiment of the invention, the membrane comprises an entanglement of one or more non-woven conductive thread(s) secured in a matrix of an elastic material.

[0032] Advantageously, at least one of the conductive wire(s) of the entanglement is a wire comprising a first strand of an electrically conductive material and a second strand of a deformable thermoformable material, said first and second strands being interlaced. Of course, the thermoformable material may be rigid or even elastic.

[0033] Advantageously, the thermoformable material is a silicone.

[0034] Advantageously, the matrix is ​​obtained from the thermoformable material of the second strand.

[0035] Advantageously, the interlacing of the first and second strands is obtained by wrapping. Of course, the interlacing can be obtained by any other technique for binding strands or threads such as for example weaving, knitting or by melting or at least partial fusion of at least one of the strands.

[0036] The invention also relates to a reflector antenna comprising a reflector comprising a membrane as previously described.

[0037] The invention also relates to a planar antenna comprising a radiating panel comprising a membrane as previously described.

[0038] The invention further relates to a method for manufacturing an antenna reflector, in particular a membrane antenna reflector according to the invention as previously described. The invention also relates to a method for manufacturing an antenna comprising such a reflector.

[0039] The invention further relates to a method for manufacturing a radiating panel for a planar antenna, and in particular a radiating panel comprising a membrane according to the invention as previously described. Brief description of the figures

[0040] Other characteristics and advantages of the invention will appear during the reading of the detailed description which follows for the understanding of which reference will be made to the appended drawings in which:

[0041] [Fig-1] shows schematically and in an isometric view, an embodiment example of a membrane according to the invention;

[0042] [Fig.2] schematically shows a reflector antenna according to an exemplary embodiment of the invention;

[0043] [Fig.3] schematically shows a deployable reflector antenna according to an exemplary embodiment of the invention. Detailed description of the invention

[0044] Various aspects of various embodiments of an antenna reflector according to the invention are described in more detail below, with reference to the accompanying drawings.

[0045] From a functional point of view, the main characteristics of an antenna include in particular: the range of frequencies covered, the radiation characteristics including the radiation pattern, the gain, the directivity, and the efficiency (which is linked to the intrinsic losses) and the impedance adaptation. The latter is very often obtained by comparing the energy transmitted to the antenna and the energy reflected on the injection by the antenna.

[0046] It should be noted that it is difficult to obtain antennas having both good performance and small dimensions. Indeed, the wavelengths of the frequency range covered by the antenna generate constraints on the sizing of the antenna. On the other hand, the gain of the antenna is generally also linked to the dimensions of the antenna (for example for a reflector involving the square of the surface).

[0047] It is also noteworthy that the condition of the surface of the reflector also influences the performance of the antenna. Indeed, typically, irregularities or imperfections whose dimensions are greater than one tenth or one twentieth of the operating wavelength of the antenna influence the performance of the antenna.

[0048] Other characteristics are important when using an antenna. For example, the mass and dimensions of the antenna impact its portability or the pointing methods.

[0049] Its mechanical characteristics and in particular its deformation under the effect of wind or any other constraint generally results from a performance / mass compromise.

[0050] Another important characteristic of the antenna, particularly in a spatial context, is its ability to be confined in order to reduce its size. (particularly during the launch of a satellite) when it is not in operation and therefore can also be deployed when it is activated (for example in space).

[0051] In the context of the application in a spatial context, among the important characteristics are the mass, the possibility of confining the antenna and of deploying it as well as its dimensions / bulk.

[0052] A membrane according to the present invention can be applied in any type of reflector antenna whether for a terrestrial application or a space application. It can be applied to a parabolic, convex or planar antenna. It can take any shape and any size.

[0053] The membrane of the present invention can also be applied in any type of planar antenna whether for a terrestrial application or a space application. It can be applied to a planar antenna whose radiating panel has any shape (rectangle, strip, square, polygon, disk, etc.). It can be flat or three-dimensional, for example convex or concave. It can take any shape and any size.

[0054] A membrane according to the present invention can also be applied in any other type of antenna.

[0055] In relation to [Fig.l] an elastic membrane 1 for an antenna according to a first embodiment of the invention is presented.

[0056] In the context of the present invention, the term elastic membrane or elastic material means a membrane or material which has a hardness of less than 95 Shores A measured according to the ASTM D2240-15 standard. In the remainder of the description, when a hardness value in Shores A is mentioned, it means a hardness value in Shores A measured according to the ASTM D2240-15 standard. According to one embodiment, a material is said to be elastic if it has a hardness of less than or equal to 75 Shores A.

[0057] Thus, an elastic membrane according to the invention can be any elastic or plastic membrane, for example, having a structure with variable geometry which retains its shape integrity even when deformed by mechanical action, crumpled or folded and reversibly allowing the return to a shape pre-established by the unfolding device.

[0058] Thus, an elastic membrane according to the present invention may be, for example, a deformable membrane, capable of passing from a state with a reduced surface area to a state with an extended surface area, while maintaining isomorphism between the two structures. Such a membrane may be obtained by all thread bonding techniques and even by melt-bonding techniques.

[0059] In the case of a transition from a crumpled shape to a smoothed shape, this deployed structure can retain its shape integrity even when deformed by a mechanical action. This structure can reversibly allow the return to a crumpled shape by the unfolding device.

[0060] According to the present embodiment of the invention, the membrane 1 comprises an entanglement of one or more non-woven conductive thread(s) secured in a matrix of a flexible material.

[0061] Of course, the entanglement of thread(s) can be made from a single thread or portion of thread or from several threads or portions of threads.

[0062] Thus, the present invention can implement technical wires. For example, wires having high electrical conductivity. For example, the electrical conductivity can be modulated by varying the mixtures of constituents. For example, structural forming materials (carbon structures, thermoformable materials, etc.) and materials for electrical conduction (for example based on metals such as copper, silver, stainless steel, aluminum or any other metal or alloy or any conductive structure) can be combined.

[0063] Thus, for example and as illustrated by [Fig. 1], to obtain the membrane 1, an entanglement 11 is produced in which at least one of the conductive thread(s) of the entanglement is a thread 111 comprising a first strand of an electrically conductive material and a second strand of a deformable thermoformable material. For example, the first and second strands are interlaced. Of course, some of the threads according to the invention may comprise any number of strands (for example, a third textile strand may be added to the first and second strands in the interlacing). Some other threads may comprise only a single strand. According to alternatives of the present embodiment of the invention, some or all of the first and second strands may not be interlaced but only linked or associated or even arranged close to each other. According to other alternatives of the present embodiment of the invention, some or all of the threads comprise a first strand (core) around which the second strand forms a sheath.In the present embodiment, each of the wires used to make the membrane comprises a first copper strand and a second silicone strand.

[0064] Of course, in accordance with the invention, any thermofusible material or any mixture of thermofusible materials incorporating a metallic electrically conductive substrate or any other electrical conductor such as, for example, carbon may also be used.

[0065] Of course, any elastic material compatible with thermoforming could be used within the framework of the present invention such as polymers (for example polypropylene or “PP”), charged polymers, doped polymers, copolymers whose hardness or elasticity can be modulated, resins, ethylene-vinyl acetate (EVA), polystyrene (PS), polyethylene (PE), polypropylene (PP), polycarbonate (PC), acrylonitrile butadiene styrene (ABS), polyvinyl chloride (PVC), polymethyl methacrylate (PMMA), high impact polystyrene (SB),...

[0066] Polymers or resins may be loaded into EVA to modulate the elasticity of the yarn or strand.

[0067] The interlacing of the first and second strands to form a yarn may, for example, result from a wrapping technique. The company Filix, for example, offers such yarns. It may result from any other technique. Alternatively, the strands may, for example, be interlaced (manually or by machine) so as to form one or more braids.

[0068] Thus, the present invention, according to certain variants, makes it possible to benefit from the great flexibility linked to the characteristics of the textile threads (when such threads or strands are implemented). According to certain embodiments of the invention, more or less stiffened and more or less flexible or more or less stretchable threads can be implemented.

[0069] According to one embodiment of the invention, the entanglement of the thread(s) can be obtained manually, for example a user can distribute the thread(s) on a surface or in a mold 122 so that, for example, the entanglement obtained has a certain homogeneity. Alternatively, the entanglement can be obtained using a machine. Of course, the entanglement of the thread(s) can be obtained by any material assembly technique (such as polymers, metals, etc.), whether by melting methods or traditional techniques (for example, fibril bonding, or more complex techniques of assembled threads such as wrapping, are some examples).

[0070] According to variants of the present invention, some of the yarn(s) may be woven or knitted or non-woven over a portion or all of the surface of the membrane.

[0071] According to one embodiment of the invention, the matrix of an elastic material is for example obtained by casting or even by melting an elastic material (for example silicone made liquid or at least malleable) on or within the entanglement. According to another embodiment, the matrix of elastic material can be obtained by applying heat (for example by thermoforming) to the entanglement of wire(s) 11 previously placed in a mold 122 so that the thermoformable material of the second strand(s) of the wire(s) take the shape of the mold which is that of the membrane 1 that it is desired to obtain. Optionally, a mechanical pressure and / or pressure can be added to the entanglement of the wire(s) during thermoforming. Thus, the entanglement of non-woven conductive wires is finally secured in a matrix of an elastic material.

[0072] The membrane may have a two-dimensional shape such as a disk or a three-dimensional shape such as a parabola or any other two- or three-dimensional shape as previously indicated.

[0073] Thus, in accordance with the present invention, the membrane may be shaped, for example, by thermoforming and applying mechanical pressure such as interlocking. Thus, in accordance with the present invention, the membrane may have a three-dimensional shape or structure after thermoforming.

[0074] The structure of the membrane surface can be either solid or meshed in the sense of antenna installers, i.e. openwork while respecting the constraints linked to the working wavelength.

[0075] Such a membrane may be used, for example, as a reflector in a reflector antenna. For example, such a membrane may be used in a parabolic antenna. Such a membrane may be used, for example, as a radiating panel in a panar antenna, for example a radiating strip.

[0076] In relation to [Fig.2], a reflector antenna 2 according to an exemplary embodiment of the invention is presented.

[0077] For example, the antenna 2 is a parabolic antenna comprising a source 21 placed at the focus of the antenna 2.

[0078] For example, the reflector is the membrane 1 previously described which has a conductive and radiating or reflecting surface of the waves due to the entanglement of conductive wire(s).

[0079] Thus, thanks to the invention, it is possible to obtain improved electrical and mechanical properties of the reflector (for example the membrane) thanks to the pooling of materials.

[0080] Thus, the radiating or reflecting conductive surface may be an assembly or entanglement of at least one thermoformed conductive wire(s) (for example, conductor associated with thermoformable). In accordance with the invention, the structure of the membrane may optionally be reinforced by adding at least one complementary reinforcement element(s), for example at least one strand or wire, for example made of thermoformable carbon, inserted into the entanglement.

[0081] It is also possible to optionally provide the membrane locally or over its entire surface with one or more additional heating elements, for example at least one strand or wire, for example made of an electrically conductive material, inserted into the entanglement which makes it possible to provide locally or over the entire surface or volume of the membrane a thermal increase by the effect of Ohm's law or Joule effect.

[0082] The surface quality of the antenna as well as the precision in its structure can be mechanically managed to obtain, for example, very good surface regularity. by using a mold and exerting heat pressure on the wire structure (or tangle) which will take on the shape on which it is pressed.

[0083] The present invention relates, in at least one of its embodiments, to a deployable membrane for an antenna capable of taking a first folded state (or even folded or even crumpled) in which the size of the membrane is reduced and a second deployed state (or even unfolded or even uncreased) in which the membrane has an optimal geometry for the antenna. According to one embodiment of the invention, the membrane comprises at least one arm secured to the membrane, said arm comprising a shape memory material. The membrane may comprise a single arm or several arms.

[0084] The deployable membrane may be an elastic membrane of the type previously described or even any other type of membrane, for example a metal sheet or a metallized sheet. The deployable membrane may also be made from superelastic metal.

[0085] A deployable membrane according to the present invention can be applied in any type of reflector antenna whether for a terrestrial application or a space application. It can be applied to a parabolic, convex or planar antenna. It can take any shape and any size.

[0086] The deployable membrane of the present invention can also be applied in any type of planar antenna whether for a terrestrial application or a space application. It can be applied to a planar antenna whose radiating panel has any shape (rectangle, strip, square, polygon, disk, etc.). It can be flat or three-dimensional, for example convex or concave. It can take any shape and any size.

[0087] A deployable membrane according to the present invention can also be applied in any other type of antenna.

[0088] According to one embodiment, at least one of the arm(s) comprises a wire comprising a first strand made of a shape memory material and a second strand made of an electrically conductive material, said second strand being wound around the first strand.

[0089] According to another embodiment of the invention, each of the arm(s) comprises a wire made of an alloy of a shape memory material (for example allowing the control of the deployment of the antenna) and an electrically conductive material.

[0090] For example, a shape memory material according to the invention is a shape memory material that can be controlled by thermal effect, for example Nitinol (which is an alloy based on nickel and titanium).

[0091] According to a first embodiment of the invention, the membrane has a parabola shape in the deployed state and in that it comprises several arms secured to the inner surface of the dish and extending from the center of the dish towards the periphery of the dish when in the deployed state. The invention according to this first embodiment also relates to a reflector antenna comprising a reflector comprising the membrane.

[0092] Thus, the membrane of the parabola can be folded mechanically by a user or by a machine so that it takes the folded state. Once in the folded state of the membrane, the application of electrical energy to the arm(s) of the membrane will, by Ohm effect in the electrical conductor (for example in the electrically conductive strand of the arm or in the electrically conductive material of the alloy of each arm) of each arm, generate heat which will be applied to the shape memory material (activated by heat) of each arm. Thus, each arm will resume its equilibrium shape by making the membrane pass into its deployed state (corresponding to the parabola). This will therefore allow the deployment of the membrane.

[0093] According to a second embodiment of the invention, the membrane has a strip shape in the deployed state and in that it comprises at least one arm secured in a parallel manner to the strip when in the deployed state. The invention according to this first embodiment also relates to a planar antenna comprising a radiating panel comprising the membrane.

[0094] Thus, the membrane of the headband can be folded mechanically by a user or by a machine so that it takes the folded state. Once in the folded state of the membrane, the application of electrical energy to the arm(s) of the membrane will, by Ohm effect in the electrical conductor (for example in the electrically conductive strand of the arm or in the electrically conductive material of the alloy of each arm) of each arm, generate heat which will be applied to the shape memory material (activated by heat) of each arm. Thus, each arm will resume its equilibrium shape by making the membrane pass into its deployed state (corresponding to the headband). This will therefore allow the deployment of the membrane.

[0095] A deployable reflector antenna according to an exemplary embodiment of the invention is shown in connection with [Fig. 3]. For example, the antenna is the previously described antenna 2 and the reflector comprises a membrane as previously described.

[0096] The wires or other constituents of the reinforcement structure can then be associated (for example by producing a covering with a thermoformable multi-strand carbon wire) with a shape memory alloy wire, thus making it possible to produce a wire structure of variable conductivity and therefore associating electrical conduction.

[0097] The present invention allows the pooling of wires or strands having various functionalities such as shape memory by using, for example, wires of shape memory alloys which can be controlled, for example, by thermal effect.

[0098] Thus, in certain membranes according to the invention, the Ohm's law characteristics make it possible to ensure the control of the deployment of the membrane of the antenna in an electrical manner. Indeed, the control of the electrical energy 311 supplied to the electrically conductive strand or to the electrically conductive material of the alloy of the arm(s) (comprising a shape memory material) makes it possible to locally create a thermal release by Ohm's law and thus activate the deployment of the arm(s) (and therefore of the membrane and therefore of the antenna) from a folded state 32 to a deployed state 31.

[0099] Within the framework of the present invention, an electrical conductivity may be chosen that can be adjusted by acting on the mixtures of constituents and a mix of structural forming materials (carbon structures, thermoformable materials) and conduction materials (for example based on metal such as copper, silver, stainless steel, aluminum or other). Indeed, in certain cases it may be advantageous to reduce the conductivity to increase the Joule effect by greater heat dissipation.

[0100] In the case of a reflector or radiating surface type antenna structure, the unfolding (or folding) sub-functionality can be ensured in particular by the following effects:

[0101] i) the natural tendency to resume the shape initiated during thermoforming and creation by the flexibility and constitution of the structure (for example with carbon reinforcements on a proofreader providing stability to the mechanical structure);

[0102] ii) the distribution of the wire structure described above which exerts, during the rise in temperature by Joule effect and Ohm's law, a controlled and pre-calculated mechanical action to achieve, by the action of the shape memory, the targeted configuration (reflector unfolded, folded, radiating strip rolled up, unrolled or other).

[0103] The present invention thus allows, in at least one of its embodiments, the use of an entanglement of non-woven materials or threads but assembled by thermoforming and mechanical pressure, with a combination of electrical conduction and physicochemical properties mixing several materials or threads forming a membrane with a conductive or radiating surface to produce strip-type antennas or deformable antenna systems with focusing by reflector and source produced with this same approach.

[0104] The present invention thus allows, in at least one of its embodiments, the production of antennas of the unfoldable or folding reflector type using in its structure pooling of shape memory wires and conductive wires, for example with thermal dissipation, thus producing a wire to allow, under the action of an electrical power, a modification of the folded configuration to unfolded or vice versa.

[0105] The present invention thus allows, in at least one of its embodiments, the production of unfoldable or foldable radiating band type antennas using in its structure of mutualizations of shape memory wires and conductive wires, for example, with thermal dissipation thus creating a wire to allow under the action of an electric power a modification of the folded configuration to unfolded or vice versa.

[0106] The present invention thus allows, in at least one of its embodiments, the use of a shape memory material in a deployable antenna reflector to activate the deployment or folding of the reflector.

[0107] The present invention thus allows, in at least one of its embodiments, the use of a shape memory material in a deployable radiating strip type antenna to activate the deployment or folding of the strip.

[0108] The invention also relates to a reflector antenna whose reflector comprises a membrane as previously described.

[0109] The invention also relates to a planar antenna comprising a radiating panel which itself comprises a membrane as previously described.

[0110] The invention further relates to a method for manufacturing an antenna reflector, in particular a membrane antenna reflector according to the invention as previously described. The invention also relates to a method for manufacturing an antenna comprising such a reflector.

[0111] The invention further relates to a method for manufacturing a radiating panel for a planar antenna, and in particular a radiating panel comprising a membrane according to the invention as previously described. List of reference signs

[0112] 1 membrane

[0113] 11 tangle of threads

[0114] 111 thread

[0115] 122 mold

[0116] 2 antenna

[0117] 21 source

[0118] 31 deployed state

[0119] 32 folded state

[0120] 311 electrical energy

Claims

Claims

1. Deployable membrane (1) for an antenna (2) capable of taking a first folded state (32) in which the size of the membrane is reduced and a second deployed state (31), characterized in that it comprises at least one arm secured to the membrane, said arm comprising a shape memory material, and in that it comprises an entanglement (11) of one or more non-woven conductive thread(s) secured in a matrix of an elastic material, at least one of the conductive thread(s) of the entanglement being a thread (111) comprising a first strand of an electrically conductive material and a second strand of a deformable thermoformable material, said first and second strands being intertwined.

2. Deployable membrane (1) according to claim 1, characterized in that at least one of the arm(s) comprises a wire comprising a first strand of a shape memory material and a second strand of an electrically conductive material, said second strand being wound around the first strand.

3. Deployable membrane (1) according to claim 1, characterized in that at least one of the arm(s) comprises a wire made of an alloy of a shape memory material and an electrically conductive material.

4. Deployable membrane (1) according to any one of claims 1 to 3, characterized in that the membrane has a parabola shape in the deployed state and in that it comprises several arms secured to the internal surface of the parabola and extending from the center of the parabola towards the periphery of the parabola when in the deployed state.

5. Deployable membrane (1) according to any one of claims 1 to 3, characterized in that the membrane has a strip shape in the deployed state and in that it comprises at least one arm secured in a parallel manner to the strip when in the deployed state.

6. Membrane (1) according to any one of the preceding claims, characterized in that the matrix is ​​obtained from the thermoformable material of the second strand.

7. Reflector antenna (2) characterized in that it comprises a reflector comprising a membrane (1) according to any one of claims 1 to 4 and 6.

8. Planar antenna characterized in that it comprises a radiating panel comprising a membrane according to any one of claims 1 to 3 and 5 to 6.

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