Reconfigurable antenna

Abstract

Reconfigurable Antenna This description relates to an antenna (100) comprising: – an amplifying array (101) comprising a plurality of first elementary cells (103); and – a transmitting array (105) comprising a plurality of second elementary cells (107), in which the amplifying array (101) is configured to radiate, or to be irradiated, by the transmitting array (105). Figure for the abbreviation: Fig. 1

Description

Title of the invention: Reconfigurable antenna Technical field

[0001] The present description relates generally to electronic devices, more particularly to reconfigurable antennas. Prior art

[0002] Compared to traditional antennas, reconfigurable antennas can have improved gain and provide access to additional functionalities, for example electronic depointing or emission of multiple, pinched or shaped beams. This benefits the development of numerous applications, such as radar systems, detection systems and communication systems from the C band (from approximately 4 to 8 GHz) to the D band (from approximately 110 to 170 GHz). The use of reconfigurable antennas is also envisaged in a frequency band located around 300 GHz.

[0003] Multiple fields of application are likely to benefit from reconfigurable antennas, including: - automotive radars for assistance and / or driving assistance, for example for active safety purposes; - very high resolution imaging and surveillance systems; - very high-speed millimeter wave communication systems, for example for inter- or intra-building communications in a home or building automation environment; - antennas for space applications, for example Ka-band LEO (Low Earth Orbit) ground-satellite telemetry links, reflector antennas dedicated to satellite communications with reconfigurable primary feed, satellite on the move (SOTM) telecommunications systems, Internet access devices or systems, television broadcasting devices or systems, etc.; and - point-to-point and point-to-multipoint communication systems such as metropolitan area networks, fronthaul and backhaul systems for cellular networks, radio access for 5G mobile networks, etc.

[0004] Among the existing high-gain antennas, reflector antennas have in particular been proposed. These antennas are however complex and expensive to produce because the reflectors require, particularly for high-frequency applications, a very precise curvature. In addition, motors are used to direct the beam in the direction desired. Phased array antennas have been proposed to allow electronic beam control. However, these antennas are expensive to develop and produce, particularly since they include amplification modules to compensate for losses induced by phase shift circuits.

[0005] Other reconfigurable antennas with depointing and / or beamforming have also been proposed. Among these antennas, there are in particular transmit array antennas (transmitarray antennas), also called discrete lens antennas. Existing transmit array antennas generally comprise a radiating panel comprising reconfigurable elementary cells, or transmitting cells. Each elementary cell of the radiating panel comprises a first antenna element irradiated by an electromagnetic field emitted by one or more focal sources, a second antenna element transmitting a modified signal to the outside of the antenna, and a coupling element between the first and second antenna elements.The elementary cells are intended to control an electromagnetic field distribution in the vicinity of a radiating aperture of the antenna, thus making it possible to produce one or more beams in a given direction or to synthesize a beam with a defined template. In an ideal case, each elementary cell is capable of compensating for each path difference between the focal source(s) and the radiating aperture. In practice, in order to simplify the antenna, the elementary cells can only compensate for a limited number of phase states, for example 2N phase states, with N a positive integer, in the case of N-bit phase quantization compensation. The same transmitter network can alternate between transmission and reception phases, provided that it is devoid of non-reciprocal elements such as amplifiers or attenuators.Otherwise, the transmitting network can only operate in transmission or reception.

[0006] However, transmitting array antennas suffer from various drawbacks. In particular, existing transmitting array antennas have a relatively large thickness, imposed by a need to distance the focal source(s) from the transmitting array. Summary of the invention

[0007] It would be desirable to overcome all or part of the disadvantages of existing reconfigurable antennas. More particularly, there is a need to have reconfigurable antennas having improved performance, reduced energy consumption and smaller size compared to existing reconfigurable antennas, in order, for example, to meet the needs of applications such as communication satellites (SATCOM).

[0008] For this, one embodiment provides an antenna comprising: - an amplifier network comprising a plurality of first elementary cells; and - a transmitter network comprising a plurality of second elementary cells, in which the amplifier network is configured to radiate, or to be radiated, by the transmitter network.

[0009] According to one embodiment, each first elementary cell comprises a first antenna element located opposite the transmitter network.

[0010] According to one embodiment, each first elementary cell further comprises at least one amplifier connected to the first antenna element.

[0011] According to one embodiment, each first elementary cell comprises: - a first amplifier, preferably a power amplifier, intended to amplify a signal emitted by the antenna; - a second amplifier, preferably a low noise amplifier, intended to amplify a signal received by the antenna; and - a switch configured to activate the first or second amplifier depending on a control signal.

[0012] According to one embodiment, each first elementary cell is connected to a radiofrequency signal transmission / reception circuit.

[0013] According to one embodiment, the antenna further comprises at least one source configured to irradiate, or to be irradiated, by the amplifier network.

[0014] According to one embodiment, said at least one source is connected to a radiofrequency signal transmission / reception circuit.

[0015] According to one embodiment, each first cell further comprises a second antenna element located opposite said at least one source.

[0016] According to one embodiment, said at least one source is a single horn antenna.

[0017] According to one embodiment, the antenna comprises fewer first elementary cells than second elementary cells, preferably four times fewer first elementary cells than second elementary cells.

[0018] According to one embodiment, each second elementary cell comprises third and fourth antenna elements connected by a phase shift circuit.

[0019] According to one embodiment, the amplifier network is devoid of phase shift circuits. Brief description of the drawings

[0020] These and other features and advantages will be set forth in detail in the following description of particular embodiments made without limitation in relation to the attached figures among which:

[0021] [Fig.l] is a schematic and partial side view of a reconfigurable antenna according to one embodiment;

[0022] [Fig.2] is a detail view of a part of the antenna of [Fig.l];

[0023] [Fig.3] is a schematic and partial top view of the antenna of [Fig.l] according to one embodiment;

[0024] [Fig.4] is a schematic and partial side view of a reconfigurable antenna according to one embodiment; and

[0025] [Fig.5] is a detail view of part of the antenna of [Fig.4]. Description of the embodiments

[0026] The same elements have been designated by the same references in the different figures. In particular, the structural and / or functional elements common to the different embodiments may have the same references and may have identical structural, dimensional and material properties.

[0027] For the sake of clarity, only the steps and elements useful for understanding the described embodiments have been shown and are detailed. In particular, the manufacturing methods of the described transmitter networks will not be detailed, the production of the described structures being within the reach of the person skilled in the art from the indications of the present description, for example by implementing standard printed circuit manufacturing techniques.

[0028] Unless otherwise specified, when referring to two elements connected to each other, this means directly connected without intermediate elements other than conductors, and when referring to two elements connected (in English "coupled") to each other, this means that these two elements can be connected or be connected by means of one or more other elements.

[0029] In the following description, when reference is made to absolute position qualifiers, such as the terms "front", "back", "top", "bottom", "left", "right", etc., or relative position qualifiers, such as the terms "above", "below", "upper", "lower", etc., or to orientation qualifiers, such as the terms "horizontal", "vertical", etc., reference is made, unless otherwise specified, to the orientation of the figures.

[0030] Unless otherwise specified, the expressions “about”, “approximately”, “substantially”, and “of the order of” mean to within 10%, preferably to within 5%.

[0031] In the following description, the terms “insulator” and “conductor” mean respectively, unless otherwise specified, electrically insulating and electrically conductive.

[0032] [Fig.l] is a schematic and partial side view of a reconfigurable antenna 100 according to one embodiment.

[0033] According to this embodiment, the reconfigurable antenna 100 comprises an amplifier network 101 comprising a plurality of elementary cells 103, and a transmitter network 105 comprising a plurality of elementary cells 107. According to one embodiment, the amplifier network is configured to irradiate or to be irradiated by the transmitter network 105. The amplifier network 101 is preferably positioned in a near-field region of the transmitter network 105.

[0034] The elementary cells 103 of the amplifier network 101 are for example arranged in a matrix according to rows and columns. Furthermore, the elementary cells 103 are for example substantially located in the same plane, the amplifier network 101 being in this case of the planar type. In the example illustrated, each elementary cell 103 comprises several antenna elements 103b, for example four antenna elements 103b (only two antenna elements 103b of each elementary cell 103 are visible in [Fig.l]), located on the side of a face of the amplifier network 101 arranged opposite the transmitter network 105. By way of example, the amplifier network 101 is produced using planar technology, for example on a printed circuit board.

[0035] Similarly, the elementary cells 107 of the transmitter network 105 are for example arranged in a matrix according to rows and columns. Furthermore, the elementary cells 107 are for example substantially located in the same plane, for example a plane substantially parallel to the plane of the amplifier network 101. By way of example, the amplifier network 101 is separated from the transmitter network 105 by a distance of the order of a central transmission and / or reception wavelength of the antenna 100. Each elementary cell 107 comprises for example a first antenna element 107a, located on the side of a first face of the transmitter network 105 arranged opposite the amplifier network 101, and a second antenna element 107b, located on the side of a second face of the transmitter network 105 opposite the first face. The second face of the transmitter network 105 is for example turned towards a transmission medium, or external medium, of the antenna 100.

[0036] In the example shown, the reconfigurable antenna 100 comprises a number of elementary cells 103 strictly less than the number of elementary cells 107. By way of example, the reconfigurable antenna 100 comprises four times fewer elementary cells 103 than elementary cells 107. This example is however not limiting, the reconfigurable antenna 100 being able, as a variant, to comprise for example nine or sixteen times fewer elementary cells 103 than elementary cells 107.

[0037] In the example illustrated, the amplifier network 101 comprises a number of elements of antenna 103b equal to the number of first antenna elements 107a of the transmitter network 105, each antenna element 103b of the amplifier network 101 being for example located opposite one of the first antenna elements 107a of the transmitter network 105. However, this example is not limiting and the amplifier network 101 may, as a variant, comprise a number of antenna elements 103b strictly less, or strictly greater, than the number of first antenna elements 107a of the transmitter network 105.

[0038] Although only five elementary cells 103 and ten elementary cells 107 have been shown in [Fig.l], the reconfigurable antenna 100 can of course comprise numbers of elementary cells 103 and elementary cells 107 different from those shown, for example several tens, several hundreds or several thousands of elementary cells 103 and elementary cells 107.

[0039] In the example illustrated, the elementary cells 103 of the amplifier network 101 are connected to a circuit 109. The circuit 109 is for example a circuit for transmitting / receiving radiofrequency signals, for example a circuit intended to produce signals to be transmitted by the reconfigurable antenna 100 and / or to process signals received by the reconfigurable antenna 100. This example is however not limiting, the circuit 109 being able to further implement additional functions such as analog-digital conversion, filtering, impedance matching, interference elimination functions, etc. By way of example, the elementary cells 103 are connected to the circuit 109 by conductive tracks and / or conductive vias of the printed circuit board in and on which the amplifier network 101 is produced.

[0040] [Fig.l] illustrates more particularly a case in which the reconfigurable antenna 100 operates in transmission. In this case, each elementary cell 103 of the amplifier network 101 is capable of receiving a signal originating from the circuit 109 and of emitting electromagnetic radiation, corresponding to the received signal, from its antenna elements 103b towards the transmitter network 105. Each elementary cell 107 of the transmitter network 105 is capable of receiving, on its first antenna element 107a, the electromagnetic radiation emitted by the elementary cells 103 of the amplifier network 101 and of re-emitting this radiation from its second antenna element 107b, for example by introducing a known phase shift ¢).

[0041] The characteristics of the near-field or far-field radiation produced by the antenna 100, in particular its shape (or size), its intensity and its maximum emission direction (or pointing direction), depend on the values ​​of the phase shifts respectively introduced by the different elementary cells 107 of the transmitter network 105.

[0042] Although not shown, the reconfigurable antenna 100 may, as alternatively, operate in reception. In this case, each elementary cell 107 of the transmitter network 105 is capable of receiving electromagnetic radiation coming from the external environment on its second antenna element 107b and of re-emitting this radiation from its first antenna element 107a, towards the amplifier network 101, with the phase shift ¢. Each elementary cell 103 of the amplifier network 101 is capable of receiving, on its antenna elements 103b, the electromagnetic radiation emitted by the elementary cells 107 of the transmitter network 105 and of providing, to the circuit 109, a signal corresponding to the received electromagnetic radiation.

[0043] The transmitter network 105 of the antenna 100 is said to be reconfigurable when the elementary cells 107 are electronically controllable, individually, to modify their phase shift value ¢) and / or their amplitude, which makes it possible to dynamically modify the characteristics of the radiation generated by the antenna, and in particular to modify its pointing direction without mechanically moving the antenna or a part of the antenna by means of a motorized element.

[0044] [Fig. 2] is a detailed view of a portion of the reconfigurable antenna 100 of [Fig. 1]. [Fig. 2] illustrates more precisely an elementary cell 103 and two elementary cells 107 located opposite each other.

[0045] In the example shown, the elementary cell 103 comprises an amplification circuit 200 comprising a switch 201, for example a single pole double throw (SPDT) switch. In this example, the switch 201 more precisely comprises an input connected to the circuit 109, a first output connected to an input of a first amplifier 203 (PA) of the amplification circuit 200, and a second output connected to an output of a second amplifier 205 (LNA) of the amplification circuit 200. The switch 201 receives for example a control signal to connect its input to its first output, when the reconfigurable antenna 100 is used in transmission, and to its second output, when the reconfigurable antenna 100 is used in reception.

[0046] The amplifier 203 of the elementary cell 103 is for example intended to amplify a signal emitted by the antenna 100. By way of example, the amplifier 203 is a power amplifier, for example a class A linear amplifier in CMOS (Complementary Metal-Oxide-Semiconductor) SOI (Silicon On Insulator) technology, for example of the type described in the article by A. Hamani, A. Siligaris, B. Blampey and JLG Jimenez entitled “167-GHz and 155-GHz High Gain D-band Power Amplifiers in CMOS SOI 45-nm Technology” from the fifteenth “European Microwave Integrated Circuits Conference (EuMIC)” in Utrecht, the Netherlands in 2021, pages 261 to 264.

[0047] The amplifier 205 of the elementary cell 103 is for example intended to amplify a signal received by the antenna 100. For example, the amplifier 205 is a low noise amplifier (LNA). This makes it possible to optimize a noise factor of the elementary cell 103 when it is used for reception. For example, the amplifier 205 comprises a class “AB” amplifier comprising for example one or two operating stages. The amplifier 205 has for example an electrical power of between 10 and 20 mW.

[0048] In the example shown, the amplifier 203 of the elementary cell 103 comprises an output connected to each antenna element 103b of the cell. Furthermore, in this example, the amplifier 205 comprises an input connected to each antenna element 103b of the cell, for example to a region of each antenna element 103b different from a region to which the output terminal of the amplifier 203 is connected. By way of example, each antenna element 103b is a patch antenna comprising for example a conductive plane of rectangular or square shape in which a U-shaped slot is formed.

[0049] In the illustrated example, each elementary cell 107 comprises a phase shift circuit 207, a first terminal of which is connected to the antenna element 107a located opposite one of the antenna elements 103b of the elementary cell 103, and a second terminal of which is connected to the antenna element 107b facing the external environment. The phase shift circuit 207 is for example configured to apply a phase shift ¢) between the signal received by the antenna element 107a and the signal transmitted by the antenna element 107b, in the case where the reconfigurable antenna 100 operates in transmission, and to apply the phase shift ¢) between the signal received by the antenna element 107b and the signal transmitted by the antenna element 107a, in the case where the reconfigurable antenna 100 operates in reception.

[0050] [Fig. 2] illustrates an example in which each elementary cell 107 is configured to introduce a phase shift ¢) between the signals received or transmitted by the antenna element 107a and the signals transmitted or received by the antenna element 107b. This example is however not limiting, the elementary cell being able, as a variant or as a complement, to implement other functions, for example a polarization state change function making it possible to switch from a signal having a left circular polarization to a signal having a right circular polarization. By way of example, each elementary cell 107 of the reconfigurable transmitter network 105 has a structure identical or analogous to the elementary cell of the transmitter network described in the patent application EP 4117117, the cell then being for example adapted to switch between two polarization states and four phase states.

[0051] [Fig. 2] illustrates an example in which the amplification circuit 200 of the elementary cell 103 comprises the switch 201 making it possible to activate either the amplifier 203, during transmission phases, or the amplifier 205, during reception phases. This example is however not limiting, the amplification circuit 200 of each elementary cell 103 of the amplifier network 101 being able, as a variant, to be devoid of the switch 201 and to comprise only a single amplifier, for example the amplifier 203, in a case where the antenna 100 is intended to be used exclusively in transmission, or the amplifier 205, in a case where the antenna 100 is intended to be used exclusively in reception.

[0052] [Fig. 3] is a schematic and partial top view of the antenna 100 of [Fig. 1] according to one embodiment. [Fig. 3] more precisely illustrates a case in which the amplifier network 101 of the reconfigurable antenna 100 comprises four times fewer amplification circuits 200 than antenna elements 103b.

[0053] In the example shown, each amplification circuit 200 is located substantially directly above the center of a square formed by the four antenna elements 103b of the corresponding elementary cell 103. In the example illustrated, each amplification circuit 200 is connected to the circuit 109 by radiofrequency lines 301, symbolized by strong line segments in [Fig. 3]. Although this has not been detailed in [Fig. 3], power dividers may be provided at the intersections between the radiofrequency lines 301 in order to divide the power of the signal transmitted from the circuit 109 to the circuits 200.

[0054] For the purposes of simplification, the amplification circuits 200 and the antenna elements 103b have been symbolized, in [Fig.3], by squares, it being understood that the amplification circuits 200 and the antenna elements 103b may, in practice, have any shape.

[0055] The reconfigurable antenna 100 previously described in relation to FIGS. 1 to 3 has, for example, a hybrid structure between that of a phased array antenna and that of a transmitting array antenna. In particular, the antenna 100 differs from a phased array antenna in that the amplifier network 101 is devoid of phase shift circuits. This advantageously makes it possible to avoid energy losses and to eliminate tedious steps of synchronization and calibration of radiofrequency lines making it possible to link, or connect, each elementary antenna of the phased array to a control circuit, for example analogous to the circuit 109. In the case of the antenna 100, the phase shifts are applied by the transmitting network 105, for example using radiofrequency switches.

[0056] Furthermore, unlike transmitting array antennas which generally comprise one or more primary sources adapted to produce a beam of generally conical shape irradiating all or part of the transmitting array, each source primary comprising for example a horn antenna, the reconfigurable antenna 100 uses as a source the amplifier network 101 irradiating the transmitter network 105. This advantageously allows the antenna 100 to have a thickness less than that which a comparable transmitter network antenna would have. This also provides the advantage, compared to a transmitter network antenna, of facilitating the production of systems for amplifying the radiofrequency signal transmitted or received.

[0057] [Fig. 4] is a schematic and partial side view of a reconfigurable antenna 400 according to one embodiment. The reconfigurable antenna 400 of [Fig. 4] has elements in common with the reconfigurable antenna 100 of [Fig. 1]. These common elements will not be detailed again below.

[0058] The reconfigurable antenna 400 of [Fig.4] differs from the reconfigurable antenna 100 of [Fig.l] in that the antenna 400 comprises, instead of the amplifier network 101, an amplifier network 401 comprising a plurality of elementary cells 403.

[0059] The elementary cells 403 of the amplifier network 401 are for example arranged in a matrix according to rows and columns. Furthermore, the elementary cells 403 are for example substantially located in the same plane, the network 401 being in this case of the planar type. In the example illustrated, each elementary cell 403 comprises a first antenna element 403a located on the side of a first face of the amplifier network 401 arranged opposite one or more primary sources 451 (a single source 451, in the example shown), and a second antenna element 403b, located on the side of a second face of the network 401 opposite the first face. The antenna element 403b of the elementary cells 403 is for example identical or analogous to one of the antenna elements 103b of the elementary cells 103 described above. For example, the amplifier network 401 is produced using planar technology, for example on a printed circuit board.

[0060] In the illustrated example, the primary source 451 is connected to the circuit 109. The primary source comprises, for example, a horn antenna irradiating the first face of the array 401. By way of example, the central axis of each primary source is substantially orthogonal to the mean plane of the array 401.

[0061] [Fig. 4] illustrates more particularly a case in which the reconfigurable antenna 400 operates in transmission. In this case, each elementary cell 403 of the amplifier network 401 is able to receive, on its first antenna element 403a, electromagnetic radiation coming from the primary source 451, and to emit, from its second antenna element 403b, electromagnetic radiation towards the transmitter network 105. Each elementary cell 107 of the transmitter network 105 is able to receive, on its first antenna element 107a, the electromagnetic radiation emitted by the elementary cells 403 of the amplifier network 401, and to re-emit this radiation from its second antenna element 107b, for example by introducing a known phase shift ¢).

[0062] Although this has not been shown, the reconfigurable antenna 400 can, as a variant, operate in reception mode. In this case, each elementary cell 107 of the transmitter network 105 is capable of receiving, on its second antenna element 107b, electromagnetic radiation coming from the external environment and of re-emitting this radiation, from its first antenna element 107a, towards the amplifier network 401, with the phase shift ¢. Each elementary cell 403 of the amplifier network 401 is capable of receiving, on its second antenna element 403b, the electromagnetic radiation emitted by the elementary cells 107 of the transmitter network 105, and of re-emitting this radiation, from its first antenna element 403a, towards the source 451. The radiation re-emitted by the antenna element 403a is for example focused on the source 451.

[0063] [Fig. 4] illustrates an example in which the amplifier network 401 comprises a number of elementary cells 403 strictly less than the number of elementary cells 107 of the transmitter network 105. By way of example, the reconfigurable antenna 400 comprises four, nine or sixteen times fewer elementary cells 403 than elementary cells 107. This example is however not limiting, the reconfigurable antenna 400 being able, as a variant, to comprise as many elementary cells 403 as elementary cells 107.

[0064] Furthermore, [Fig. 4] illustrates an example in which each elementary cell 403 of the amplifier network 401 comprises a single first antenna element 403a and a single second antenna element 403b. However, this example is not limiting and each elementary cell 403 of the amplifier network 401 may, as a variant, comprise several first antenna elements 403a and several second antenna elements 403b.

[0065] [Fig. 5] is a detailed view of a portion of the antenna 400 of [Fig. 4]. [Fig. 5] illustrates more precisely an elementary cell 403 and two antenna elements 107 located opposite each other.

[0066] The elementary cell 403 differs for example from the elementary cell 103 previously described in that, in the elementary cell 403, the input of the switch 201 is connected to the first antenna element 403a of the elementary cell 403.

[0067] The operation of the reconfigurable antenna 400, in particular the control of the switch 201 of each elementary cell 403 depending on whether the antenna 400 is used for transmission or reception, is analogous to the operation previously described in relation to [Fig.2] for the reconfigurable antenna 100.

[0068] [Fig. 5] illustrates an example in which the elementary cell 403 comprises the switch 201 making it possible to activate either the amplifier 203, during transmission phases, or the amplifier 205, during reception phases. This example is not however not limiting, each elementary cell 403 of the network 401 may, as a variant, be devoid of the switch 201 and comprise only one amplifier, for example the amplifier 203, in a case where the antenna 400 is used exclusively in transmission, or the amplifier 205, in a case where the antenna 400 is used exclusively in reception.

[0069] The reconfigurable antenna 400 has advantages similar to those of the reconfigurable antenna 100.

[0070] Various embodiments and variants have been described. The person skilled in the art will understand that certain features of these various embodiments and variants could be combined, and other variants will appear to the person skilled in the art. In particular, the person skilled in the art is able to adjust the ratio between the number of elementary cells 103, 403 of the amplifier network 101, 401 and the number of elementary cells 107 of the transmitter network 105 depending on the application, for example depending on the heating produced by each elementary cell 103, 403. The person skilled in the art is further able to adjust the number of antenna elements of each elementary cell 103, 403 of the amplifier network 101, 401, in particular depending on the proportion of elementary cells 103, 403 of the amplifier network 101, 401 relative to the elementary cells 107 of the transmitter network 105.

[0071] Finally, the practical implementation of the embodiments and variants described is within the reach of the person skilled in the art from the functional indications given above. In particular, the practical realization of the antenna element(s), the switch and the amplifier(s) of the elementary cells of the amplifier network as well as the practical realization of the elementary cells of the transmitter network are within the reach of the person skilled in the art from the indications of the present description.

[0072] Furthermore, the elementary cells 107 of the transmitter network 105 can be calibrated in order to correct phase errors linked to the structure of the antenna.

Claims

Claims

1. Antenna (100; 400) comprising: - an amplifier network (101; 401) comprising a plurality of first elementary cells (103; 403); and - a transmitter network (105) comprising a plurality of second elementary cells (107), wherein the amplifier network (101; 401) is configured to irradiate, or to be irradiated, by the transmitter network (105).

2. Antenna (100; 400) according to claim 1, in which each first elementary cell (103; 403) comprises a first antenna element (103b; 403b) located opposite the transmitter network (105).

3. Antenna (100; 400) according to claim 2, wherein each first elementary cell (103; 403) further comprises at least one amplifier (203, 205) connected to the first antenna element (103b; 403b).

4. Antenna (100; 400) according to claim 3, wherein each first elementary cell (103; 403) comprises: - a first amplifier (203), preferably a power amplifier, intended to amplify a signal emitted by the antenna; - a second amplifier (205), preferably a low noise amplifier, intended to amplify a signal received by the antenna; and - a switch (201) configured to activate the first or the second amplifier according to a control signal.

5. Antenna (100) according to any one of claims 1 to 4, in which each first elementary cell (103) is connected to a radiofrequency signal transmission / reception circuit (109).

6. An antenna (400) according to any one of claims 1 to 4, further comprising at least one source (451) configured to irradiate, or to be irradiated, by the amplifier network (401).

7. Antenna (400) according to claim 6, wherein said at least one source (451) is connected to a radiofrequency signal transmission / reception circuit (109).

8. Antenna (400) according to claim 6 or 7, wherein each first cell (403) further comprises a second antenna element (403a) located opposite said at least one source (451).

9. An antenna (400) according to claim 6, 7 or 8, wherein said at least one feed (451) is a single horn antenna.

10. Antenna (100; 400) according to any one of claims 1 to 9, comprising fewer first elementary cells (103; 403) than second elementary cells (107), preferably four times fewer first elementary cells than second elementary cells.

11. Antenna (100; 400) according to any one of claims 1 to 10, in which each second elementary cell (107) comprises third and fourth antenna elements (107a, 107b) connected by a phase shift circuit (207).

12. Antenna (100; 400) according to any one of claims 1 to 11, in which the amplifier network (401) is devoid of phase shift circuits.

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