Transmitting array antenna cell

Abstract

Antenna cell with transmitter array The present description relates to a transmitter array cell (105) adapted to implement simultaneous two-way communication, the cell comprising: – a first antenna element (105a) located on a first face of the cell; – a second antenna element (105b) located on a second face of the cell, opposite the first face; – a transmission channel comprising, between the first and second antenna elements, a first phase shift and amplification circuit (203a); and – a reception channel comprising, between the first and second antenna elements, a second phase shift and amplification circuit (203b). Figure for abstract: Fig. 3A

Description

Title of the invention: Antenna cell with transmitting array Technical field

[0001] The present description relates generally to electronic devices and, more particularly, to the field of radio antennas with a transmitting array (“transmitarray antenna” in English). Prior art

[0002] Among the various existing radio communication antenna technologies, radio antennas known as "transmitter array" antennas are known in particular. These antennas generally comprise several elementary cells each comprising a first antenna element irradiated by an electromagnetic field emitted by one or more 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.

[0003] Existing transmitting array antennas, however, suffer from various drawbacks. Summary of the invention

[0004] There is a need to improve existing transceiver array antennas. In particular, it would be desirable to have transceiver array antennas suitable for implementing simultaneous two-way communication.

[0005] For this, one embodiment provides a transmitter network cell adapted to implement simultaneous two-way communication, the cell comprising: - a first antenna element located on a first face of the cell; - a second antenna element located on a second face of the cell, opposite the first face; - a transmission channel comprising, between the first and second antenna elements, a first phase shift and amplification circuit; and - a reception channel comprising, between the first and second antenna elements, a second phase shift and amplification circuit.

[0006] According to one embodiment, the transmission channel is adapted to transmit a first signal having a first polarization state, and the reception channel is adapted to receive a second signal having a second polarization state, different from the first polarization state.

[0007] According to one embodiment, the first and second signals have orthogonal linear polarizations.

[0008] According to one embodiment, the first and second signals have circular and linear polarizations, respectively.

[0009] According to one embodiment, each of the first and second antenna elements comprises a conductive plane of substantially square shape and first and second ports located respectively in the vicinity of first and second adjacent sides of the conductive plane.

[0010] According to one embodiment, the first and second ports of the first antenna element are located respectively directly above the first and second ports of the second antenna element.

[0011] According to one embodiment, the first and second ports of the first antenna element are connected respectively, by the first and second phase shift and amplification circuits, to the first and second ports of the second antenna element.

[0012] According to one embodiment, the first and second ports of the first antenna element are connected respectively, by the first and second phase shift and amplification circuits, to the second and first ports of the second antenna element.

[0013] According to one embodiment, the cell further comprises first and second ground planes interposed between the first antenna element and the second antenna element.

[0014] According to one embodiment, the first and second phase shift and amplification circuits are interposed between the first and second ground planes.

[0015] According to one embodiment, the first and second antenna elements and the first and second ground planes are formed in conductive levels of a printed circuit board.

[0016] According to one embodiment, the transmission and reception channels each comprise a phase shift circuit and an amplification circuit connected in series between the first antenna element and the second antenna element.

[0017] One embodiment provides a transmitter network comprising a plurality of cells as described.

[0018] According to one embodiment, the first antenna element of each cell is electrically isolated from the first antenna element of each of the other cells, and the second antenna element of each cell is electrically isolated from the second antenna element of each of the other cells.

[0019] One embodiment provides an antenna comprising a transmitting array as described and at least one source configured to irradiate one face of the array. 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 given without limitation in relation with the attached figures among which:

[0021] [Fig.l] is a schematic and partial side view of an example of a transmitting array antenna of the type to which, by way of example, the described embodiments apply;

[0022] [Fig.2] is a schematic and partial side view of an example of a transmitting array antenna according to one embodiment;

[0023] [Fig.3A] is a schematic and partial side view of an example of a transmitter network cell according to one embodiment;

[0024] [Fig.3B] is a schematic and partial top view of an example of an antenna element of the cell of [Fig.3A];

[0025] [Fig.3C] is a schematic and partial top view of an example of a ground plan of the cell of [Fig.3A];

[0026] [Fig.4A] is a schematic and partial side view of an example of a transmitter network cell according to one embodiment;

[0027] [Fig.4B] is a schematic and partial top view of an example of a ground plan of the cell of [Fig.4A]; and

[0028] [Fig.4C] is a schematic and partial top view of an example of another ground plane of the cell of [Fig.4A]. Description of the embodiments

[0029] 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.

[0030] For the sake of clarity, only the steps and elements useful for understanding the embodiments described have been shown and are detailed. In particular, embodiments of an elementary cell for a transmitting array antenna are described below. The structure and operation of the primary source(s) of the antenna, intended to irradiate the transmitting array, will not however be detailed, the embodiments described being compatible with all or most of the known primary irradiation sources for transmitting array antennas. By way of example, each primary source is adapted to produce a beam of generally conical shape irradiating all or part of the transmitting array. Each primary source comprises for example a horn antenna. By way of example, the central axis of each primary source is substantially orthogonal to the mean plane of the array.

[0031] Furthermore, 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 putting into use of standard printed circuit manufacturing techniques.

[0032] 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.

[0033] 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.

[0034] Unless otherwise specified, the expressions “about”, “approximately”, “substantially”, and “of the order of” mean to within 10%, preferably to within 5%.

[0035] [Fig.l] is a schematic and partial side view of an example of a transmitarray antenna 100 of the type to which, by way of example, the described embodiments apply.

[0036] The antenna 100 typically comprises one or more primary sources 101 (a single source 101, in the example shown) irradiating a transmitting network 103. The source 101 may have any polarization, for example linear or circular. The network 103 comprises a plurality of elementary cells 105, for example arranged in a matrix according to rows and columns. Each cell 105 typically comprises a first antenna element 105a, located on the side of a first face of the network 103 arranged opposite the primary source 101, and a second antenna element 105b, located on the side of a second face of the network opposite the first face. The second face of the network 103 is for example turned towards a transmission medium, or external medium, of the antenna 100.

[0037] Each cell 105 is capable, in transmission, of receiving electromagnetic radiation on its first antenna element 105a and of re-emitting this radiation from its second antenna element 105b, for example by introducing a known phase shift ¢). In reception, each cell 105 is capable of receiving electromagnetic radiation on its second antenna element 105b and of re-emitting this radiation from its first antenna element 105a, in the direction of the source 101, with the same phase shift ¢. The radiation re-emitted by the first antenna element 105a is for example focused on the source 101.

[0038] 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 cells 105 of the network 103.

[0039] Transmitting array antennas have the advantage, among other things, of being energy efficient and relatively simple, inexpensive and compact. This is due in particular to the fact that the transmitting arrays can be produced using planar technology, generally on a printed circuit.

[0040] The present description relates more particularly to antennas with a reconfigurable transmitter array 103. The transmitter array 103 is said to be reconfigurable when the elementary cells 105 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.

[0041] [Fig. 2] is a schematic and partial side view of an example of an antenna 200 with a transmitting array according to one embodiment. The antenna 200 of [Fig. 2] comprises elements in common with the antenna 100 of [Fig. 1]. These common elements will not be detailed again below.

[0042] In the example shown, each elementary cell 105 of the transmitter network 103 comprises a transmission channel 201a and a reception channel 201b intended respectively to transmit and receive signals, for example simultaneously. Inside each cell 105, each channel 201a, 201b connects the first antenna element 105a to the second antenna element 105b of the cell. In the example illustrated, for each cell 105, the first antenna element 105a connects a first end of the transmission channel 201a to a first end of the reception channel 201b. Similarly, the second antenna element 105b of the cell 105 connects a second end of the transmit channel 201a, opposite the first end of the channel 201a, to a second end of the receive channel 201b, opposite the first end of the channel 201b.Furthermore, the first antenna element 105a of each elementary cell 105 is electrically isolated from the first antenna element 105a of each of the other cells 105, and the second antenna element 105b of each elementary cell 105 is electrically isolated from the second antenna element 105b of each of the other cells 105.

[0043] Each transmission channel 201a comprises a phase shift and amplification circuit 203a, and each reception channel 201b comprises a phase shift and amplification circuit 203b. In the example shown, each phase shift and amplification circuit 203a, 203b comprises, between the first and second antenna elements 105a and 105b, a phase shift circuit 205a, 205b associated in series with an amplification circuit 207a, 207b.

[0044] The phase shift circuit 205a of the transmission channel 201a comprises a connected terminal, preferably connected, to the first antenna element 105a and another terminal connected, preferably connected, to a terminal, for example an input terminal, of the amplification circuit 207a, the amplification circuit 207a further comprising another terminal, for example an output terminal, connected, preferably connected, to the second antenna element 105b. Furthermore, the amplification circuit 270b of the reception channel 201b comprises a terminal, for example an input terminal, connected, preferably connected, to the second antenna element 105b and another terminal, for example an output terminal, connected, preferably connected, to a terminal of the phase shift circuit 205b, the phase shift circuit 205b further comprising another terminal connected, preferably connected, to the first antenna element 105a.

[0045] By way of example, each phase shift circuit 205a, 205b comprises at least one element chosen from a diode, for example a PIN diode, a microelectromechanical system, a varicap or varactor diode, an integrated phase shift circuit, etc. Each phase shift circuit 205a, 205b receives for example a control signal coming from a control circuit (not illustrated in [Fig.2]), for example a microcontroller, adapted to switch the signals transmitted by each circuit 205a, 205b between two distinct phase states.

[0046] The amplification circuit 207a of the transmission channel 201a is for example 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 amplification circuit 207b of the reception channel 201b is for example a low noise amplifier (LNA). This makes it possible to optimize a noise factor of the reception channel 201b. For example, each amplification circuit 207b comprises a class “AB” amplifier comprising for example one or two operating stages. Each amplification circuit 207b has for example an electrical power of between 10 and 20 mW.

[0048] In the example shown, the source 101 of the transmitting array antenna 200 is connected to an interference elimination or cancellation circuit 211. More specifically, in this example, first and second links 213a and 213b, electrically isolated from each other, connect the circuit 211 to the source 101.

[0049] The antenna 200 further comprises a processing circuit 215 connected to the circuit 211. In the example shown, the circuit 215 is connected to the circuit 211 by a transmission channel 217a comprising a digital-to-analog converter 219a associated in series with a mixer 221a (x). The circuit 211 is further connected to the circuit 215 by a reception channel 217b comprising a mixer 221b (x) associated in series with an analog-to-digital converter 219b. Each mixer 221a, 221b is for example connected to an oscillator 223a, 223b (~), for example a voltage-controlled oscillator (VCO) or a phase-locked loop (PLL).

[0050] In the example illustrated, the digital-to-analog converter 219a of the transmission channel 217a comprises input and output terminals connected respectively to the circuit 215 and to a terminal of the mixer 221a, the mixer 221a further comprising another terminal connected to the circuit 211. Furthermore, in this example, the mixer 221b of the reception channel 217b comprises a terminal connected to the circuit 211 and another terminal connected to an analog-to-digital converter input terminal 219b, the analog-to-digital converter 219b further comprising an output terminal connected to the circuit 215.

[0051] By way of example, the circuit 215 is adapted to encode and modulate a signal to be transmitted by the transmission channel 217a, and to demodulate and decode a signal received by the reception channel 217b.

[0052] The antenna 200 is configured to implement simultaneous bidirectional communication (“full-duplex”, in English), that is to say that the antenna 200 can transmit and receive signals simultaneously in the same frequency band (“In-Band Full-Duplex” - IBFD, in English). The antenna 200 is notably different from frequency division multiple access (FDMA) antennas whose transmission and reception channels are separated in frequency. A first signal to be transmitted is for example produced by the circuit 215 then transmitted, via the transmission channel 217a and the first link 213a, to the source 101 irradiating the network 103. The first signal then reaches the first antenna elements 105a of the cells 105 of the network 103 then is transmitted, via the transmission channels 201a, to the second antenna elements 105b to be radiated towards the external environment.At the same time, a second signal to be received from the external environment is for example picked up by the second antenna elements 105b of the cells 105 of the network 103 and is then transmitted, via the reception channels 201b, to the first antenna elements 105a. The second signal is then radiated towards the source 101 and is then transmitted, via the second link 213b and the reception channel 217b, to the circuit 215 to be processed.

[0053] In transmission, the first antenna element 105a receives the signal radiated by the antenna 101. The signal is then phase-shifted and amplified by the transmission channel 201a, more precisely by the phase-shift circuit 205a and by the amplification circuit 207a, respectively, then re-transmitted by the second antenna element 105b to the external medium. In reception, the second antenna element 105b receives the signal from the external medium. The signal is then amplified and then phase-shifted by the reception channel 201b, more precisely by the amplification circuit 207b and by the phase-shift circuit 205b, respectively, then re-transmitted by the first antenna element to the source 101.

[0054] The signals transmitted and received by the antenna 200 respectively have first and second distinct states or directions of polarization. By way of example, the signals transmitted and received respectively have first and second linear polarizations orthogonal to each other, the first polarization being for example a linear polarization called "vertical" and the second polarization a linear polarization called "horizontal".

[0055] As a variant, at least one of the first and second polarizations may be a circular polarization. In this case, the first and second polarizations may be circular polarizations of opposite directions, the first polarization being for example a so-called “left” circular polarization (counterclockwise, from the point of view of the source 101) and the second polarization being for example a so-called “right” circular polarization (clockwise, from the point of view of the source 101), or the first polarization being a circular polarization and the second polarization being a linear polarization. The fact of providing that the signals transmitted and received by the antenna respectively have circular and linear polarizations advantageously makes it possible to obtain a better separation of these signals.

[0056] In [Fig.2], a single source 101 has been illustrated. The source 101 is for example a so-called “bipolarization” source, capable of transmitting and receiving signals having two distinct polarizations respectively. As a variant, the source 101 can be replaced by first and second spatially separated sources, the first source being for example adapted to transmit signals having a first polarization and the second source being adapted to receive signals having a second polarization, different from the first polarization. In this case, the circuit 211 is connected to the first and second sources by the first and second links 213a and 213b, respectively.

[0057] An advantage of the antenna 200 of [Fig.2] is that it makes it possible to achieve superior performance, particularly in terms of interference cancellation, superior to that of existing antennas.

[0058] [Fig.3A] is a schematic and partial side view of the cell 105 of the transmitter network 103 according to one embodiment.

[0059] In the example shown, the cell 105 comprises two disjoint ground planes M1 and M2 substantially parallel to each other and interposed between the first and second antenna elements 105b. The first and second antenna elements 105a and 105b are, in this example, substantially parallel to each other and to the ground planes M1 and M2. In the example illustrated, the circuits 203a and 203b are interposed between the ground planes M1 and M2.

[0060] In the example illustrated in [Fig.3A], the phase shift and amplification circuit 203a is connected, by a conductive via Via, to a first port or conduction terminal PI of the first antenna element 105a. The circuit 203a is further connected, by another conductive via V2a, to a first port or conduction terminal PI of the second antenna element 105b. Similarly, the phase shift and amplification circuit 203b is connected, by a conductive via V2a, to a second port or conduction terminal P2 of the first antenna element 105a. The circuit 203b is further connected, by another conductive via V2b, to a second port or conduction terminal P2 of the second antenna element 105b.

[0061] By way of example, the first and second antenna elements 105a and 105b and the ground planes M1 and M2 are formed in conductive levels or metallization levels of a printed circuit board (PCB), the conductive levels being separated from each other by insulating levels not shown in [Fig. 3A]. The circuits 203a and 203b are for example produced in CMOS or BiCMOS (Bipolar Complementary Metal Oxide Semiconductor) technology. By way of example, the circuits 203a and 203b can be implemented in discrete or integrated components. Furthermore, an integrated circuit connected to several antennas can be provided.

[0062] [Fig.3B] is a schematic and partial top view of the first antenna element 105a of the cell 105 of [Fig.3A].

[0063] In the example shown, the first antenna element 105a is a patch antenna comprising a conductive plane of substantially square shape to which the vias Via and Vlb are connected by the ports PI and P2, respectively. This example is however not limiting, the conductive plane of the first antenna element 105a being able to have any shape, for example rectangular. In the example shown, the port PI is located in the vicinity of a first side of the square formed by the conductive plane and the port P2 is located in the vicinity of a second side of the square adjacent to the first side. In this example, the ports PI and P2 are substantially aligned with respect to the midpoints of the first and second sides, respectively.

[0064] In the example shown, the first antenna element 105a is adapted to transmit, via the port PI, a first signal having a linear polarization (a horizontal polarization, in the orientation of [Fig.3B]). In this example, the first antenna element 105a is further adapted to transmit to the source 101, from the port P2, a second signal having a linear polarization orthogonal to that of the first signal (a vertical polarization, in the orientation of [Fig.3B]).

[0065] Although this has not been illustrated in the figures, the second antenna element 105b is for example similar or identical to the first antenna element 105a. For example, the ports P1 and P2 of the second antenna element 105b are located respectively in line with the ports P1 and P2 of the first antenna element 105a. In this case, the vias V2a and V2b are for example located respectively in line with the vias V1a and V1b.

[0066] [Fig.3C] is a schematic and partial top view of the ground plane M1 of the cell 105 of [Fig.3A].

[0067] In the example shown, the vias Via and Vlb are electrically isolated from the ground plane Ml. Similarly, the vias V2a and V2b are for example electrically isolated from the ground plane M2, the ground plane M2 being for example analogous or identical to the ground plane Ml.

[0068] [Fig.4A] is a schematic and partial side view of the cell 105 according to another embodiment. The embodiment of [Fig.4A] differs from that of [Fig.3A] in that, in the embodiment of [Fig.4A], the first port P1 of the first antenna element 105a is connected to the second port P2 of the second antenna element 105b, and the second port P2 of the first antenna element 105a is connected to the first port P1 of the second antenna element 105b.

[0069] [Fig.4B] is a schematic and partial top view of the ground plane M1 of the cell 105 of [Fig.4A] and [Fig.4C] is a schematic and partial top view of the ground plane M2 of the cell 105 of [Fig.4A].

[0070] In the example shown, cell 105 comprises more precisely: - a via V3a connecting the first port PI of the first antenna element 105a to a first end of a conductive track P1a, the track PIa being for example formed in the same conductive level as the ground plane M1 and electrically isolated from the ground plane M1; - a via V4a connecting a second end of the track Pla, opposite the first end of the track Pla, to the circuit 203a; - a via V5a connecting the circuit 203a to a first end of a conductive track P2a, the track P2a being for example formed in the same conductive level as the ground plane M2 and electrically isolated from the ground plane M2; and - a via V6a connecting a second end of track P2a, opposite the first end of track P2a, to the second port P2 of the second element antenna 105b.

[0071] Although this has not been detailed in the figures so as not to overload the drawing, the cell 105 may further comprise one or more redistribution layers (RDL) of the transmitted and received radiofrequency signals, a ground signal and a power supply signal.

[0072] Similarly, cell 105 further comprises: - a via V3b connecting the second port P2 of the first antenna element 105a to a first end of a conductive track Pib, the track Pib being for example formed in the same conductive level as the ground plane Ml and electrically isolated from the ground plane Ml; - a via V4b connecting a second end of the Pib track, opposite the first end of the Pib track, to the circuit 203b; - a via V5b connecting the circuit 203b to a first end of a conductive track P2b, the track P2b being for example formed in the same conductive level as the ground plane M2 and electrically isolated from the ground plane M2; and - a via V6b connecting a second end of the track P2b, opposite the first end of the track P2b, to the first port PI of the second antenna element 105b.

[0073] In the example shown, the tracks Pla and Pib are substantially parallel to each other, and the tracks P2a and P2b are substantially parallel to each other and orthogonal to the tracks Pla and Pib.

[0074] An advantage of the embodiment of the cell 105 set out above in relation to FIGS. 4A to 4C is that it makes it possible to further reduce or cancel out interference between the signals transmitted and received by the antenna. For example, the isolation of the cell 105 of FIGS. 4A to 4C is improved by a factor of two, in decibels (dB), compared to that of the cell 105 of FIGS. 3A to 3B.

[0075] Various embodiments and variations have been described. Those skilled in the art will understand that certain features of these various embodiments and variations could be combined, and other variations will occur to those skilled in the art. In particular, the embodiment of the cell 105 detailed above in relation to FIGS. 4A to 4C is not limited to the structure described, other structures of cell 105 may be provided by those skilled in the art, based on the indications of the present description, to connect the ports P1 and P2 of the first antenna element 105a to the ports P2 and P1, respectively, of the second antenna element 105b.Furthermore, the person skilled in the art is capable of adapting the structure of the cell 105, in particular of the first and second antenna elements 105a and 105b, in the case where the polarization of the signal to be transmitted and / or of the signal received by the antenna 200 has a polarization different from a linear polarization, for example a polarization. circular.

[0076] 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 implementation of the amplification and phase shift circuits 203a and 203b of the transmission and reception channels 201a and 201b is within the reach of the person skilled in the art from the indications of the present description.

Claims

Claims

1. Cell (105) of a transmitter network (103) adapted to implement simultaneous two-way communication, the cell comprising: - a first antenna element (105a) located on a first face of the cell; - a second antenna element (105b) located on a second face of the cell, opposite the first face; - a transmission channel (201a) comprising, between the first and second antenna elements, a first phase shift and amplification circuit (203a); and - a reception channel (201b) comprising, between the first and second antenna elements, a second phase shift and amplification circuit (203b).

2. Cell according to claim 1, in which the transmission channel (201a) is adapted to transmit a first signal having a first polarization state, and the reception channel (201b) is adapted to receive a second signal having a second polarization state, different from the first polarization state.

3. The cell of claim 2, wherein the first and second signals have orthogonal linear polarizations.

4. The cell of claim 2, wherein the first and second signals have circular and linear polarizations, respectively.

5. A cell according to any one of claims 1 to 3, wherein each of the first and second antenna elements (105a, 105b) comprises a substantially square-shaped conductive plane and first and second ports (PI, P2) located respectively in the vicinity of first and second adjacent sides of the conductive plane.

6. Cell according to claim 5, in which the first and second ports (PI, P2) of the first antenna element (105a) are located respectively in line with the first and second ports (PI, P2) of the second antenna element.

7. Cell according to claim 5 or 6, in which the first and second ports (PI, P2) of the first antenna element (105a) are connected respectively, by the first and second phase shift and amplification circuits (203a, 203b), to the first and second ports (PI, P2) of the second antenna element (105b).

8. Cell according to claim 5 or 6, in which the first and second ports (PI, P2) of the first antenna element (105a) are connected respectively, by the first and second phase shift and amplification circuits (203a, 203b), to the second and first ports (P2, PI) of the second antenna element (105b).

9. A cell according to any one of claims 1 to 8, further comprising first and second ground planes (M1, M2) interposed between the first antenna element (105a) and the second antenna element (105b).

10. Cell according to claim 9, in which the first and second phase shift and amplification circuits (203a, 203b) are interposed between the first and second ground planes (M1, M2).

11. A cell according to claim 9 or 10, wherein the first and second antenna elements (105a, 105b) and the first and second ground planes (M1, M2) are formed in conductive levels of a printed circuit board.

12. A cell according to any one of claims 1 to 11, wherein the transmit (201a) and receive (201b) channels each comprise a phase shift circuit (205a, 205b) and an amplification circuit (207a, 207b) connected in series between the first antenna element (105a) and the second antenna element (105b).

13. A transmitter network (103) comprising a plurality of cells (105) according to any one of claims 1 to 12.

14. The network of claim 13, wherein the first antenna element (105a) of each cell (105) is electrically isolated from the first antenna element (105a) of each of the other cells (105), and the second antenna element (105b) of each cell is electrically isolated from the second antenna element (105b) of each of the other cells (105).

15. An antenna (200) comprising a transmitter array (103) according to claim 13 or 14 and at least one source (101) configured to irradiate a face of the array.

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