EP4000130A1

EP4000130A1 - Aerodyne with antenna and associated arrangement method

Info

Publication number: EP4000130A1
Application number: EP20736744.2A
Authority: EP
Inventors: Thibault MAISONNAT; Eric Peyrucain; Alain Lagarrigue; Valery GINEST
Original assignee: Airbus SAS; Airbus Defence and Space SAS
Current assignee: Airbus SAS; Airbus Defence and Space SAS
Priority date: 2019-07-19
Filing date: 2020-07-10
Publication date: 2022-05-25
Also published as: FR3099001A1; US20220320719A1; WO2021013589A1; WO2021013589A9

Abstract

Disclosed is a method (81) for arranging a set of antennas capable of transmitting or receiving in a radio frequency range in an existing aerodyne implemented either during an initial installation operation, or in a subsequent maintenance or update operation, the method (81) comprising the steps of: removing (811) at least one component of a structural element external to the bearing surface of the existing aerodyne, the component being substantially transparent to the radio frequency range; installing (812) the set of antennas in a zone exposed by the removal in the step (811); fitting (813) an electronic and electrical harness connecting the set of antennas to a radio communications system and to a power supply inside the fuselage; re-forming (814) the external structural element in such a way as to cover the installed set of antennas.

Description

DESCRIPTION

TITLE: AERODYNE WITH ANTENNA AND LAYOUT PROCESS

ASSOCIATE Technical Field

The present invention relates to an aerodyne comprising one or more antennas, as well as an external structural assembly and a method of arrangement thereof. It applies in particular to fixed-wing aerodynes, such as airplanes or gliders.

State of the art

The presence of antennas in aerodynes is necessary or useful for multiple communications functions, including the acquisition of information required for the good progress of the flight and the transmission of data relating to the course flown. Among these functions, aircraft connectivity can also provide an Internet connection, in particular via WiFi (for "Wireless Fidelity"), to passengers and crew.

An important aspect relating to antennas is their positioning. It is in particular known to have radome systems in the upper part of the aerodyne, on the fuselage. However, such arrangements have the drawback of increasing the drag of the aerodyne, and therefore the fuel consumption. In addition, substantial mechanical and aerodynamic tune-ups are required, at the cost of investment in time and budget. Typically, several days are thus required to install an antenna according to these solutions, relying on a highly qualified workforce. In addition, a flight authorization is only acquired under conditions of satisfactory analyzes and tests. The maintenance of the corresponding antennas, frequently made necessary by difficult navigation environments (vibrations, temperature, mechanical constraints, etc.), also requires a long immobilization of the aerodynes, thus increasing the cost price over time. It is also known practice to place a radar in an aerodyne nose cone, acting as a radome, in order to detect objects or weather conditions. Such a system however provides information limited to a front view, and is not suitable for example for communications with satellites or terrestrial relays.

Other proposed embodiments are based on coupling antennas with aircraft wings. Thus, the patent application GB-2169866 A (inventor: RS Fitzpatrick) discloses a radome capsule retractably fixed under an aircraft wing and housing a mode S radar. However, such an embodiment uses mechanisms which require installations requiring time and precision, and relatively frequent maintenance. In addition, in deployed mode, it impacts the aerodynamics of the aircraft. What is more, its positioning makes it especially effective for communications with terrestrial antennas, but not very suitable for satellite communications.

Patent application CN 103887605 (inventors Zhou Jinzhu et al.) Describes an aircraft wing incorporating array antennas (also referred to as antenna arrays, "antenna arrays" in English terminology). More specifically, the wing has a central structure bounded by an upper skin and a lower skin defining its external surfaces, each of these coatings including a central radiofrequency circuit layer framed by thermally insulating honeycomb layers and by top and bottom panels. The core layer includes an array antenna.

This realization of a wing with an integrated antenna makes possible both a reduction in weight and a preservation of the aerodynamic performance of the aircraft which is equipped with it. However, it has the drawbacks of restrictive antenna positioning requirements, closely linked to the configuration of the wing, and high exposure to external stresses.

summary The object of the present description is in particular to overcome the difficulties and drawbacks mentioned above with the existing antenna systems for aerodynes.

Its potential fields of application extend to satellite communications, but also to terrestrial networks, and are likely to offer various transmission and / or reception possibilities, in particular for leisure-oriented connectivity purposes.

In particular embodiments, the invention makes possible a rapid and simplified installation, an economical realization, a reduced maintenance, a preservation of the aerodynamic properties of the aerodyne and / or a good reliability of communications by radio waves.

To this end, the description relates to an aerodyne comprising a fuselage and at least one external structural element with a lifting surface (called the "airfoil" type in English) mounted to the fuselage and configured to provide the aerodyne with aerodynamic properties. This outer structural element includes at least one outer shell and is provided with at least one antenna.

According to the description, the antenna (s) are arranged inside the external structural element while being structurally dissociated from the external shell (s). In addition, at least part of these external shells is substantially transparent to at least one range of radio frequencies, so that the antenna (s) can (s) perform an operation chosen from at least one reception and one transmission. of radio waves through this or these part (s) of the outer shell (s).

Such an external structural element with a lifting surface can consist in particular of a wing or of a tail piece - for the latter, the lifting surface manifests itself substantially in the event of a disturbance of balance with regard to a cruising flight. stable, and has a low or negligible impact otherwise. It can thus be in particular a dorsal fin also called vertical stabilizer (stabilization in yaw) or a horizontal stabilizer (stabilization in pitch).

The external structural element advantageously corresponds to a fixed part of the aerodyne, which makes it possible to facilitate antenna orientation stability. The aerodyne is therefore advantageously fixed-wing. The external structural element can however also consist of a fixed part of a rotary wing aerodyne, such as for example a tail or possibly a fixed wing of a helicopter.

The term “external structural element with a bearing surface” is understood to mean a structural assembly forming an aerodynamic unit, whatever the composition or the multiplicity of the elements which constitute it. For example, such a structural element can optionally include a vertical fin comprising a main structure, as well as lower, longitudinal and upper cowls of this main structure.

The outer shell (or outer shells) define (define) at least part of the contours of the structural element, that is, its interface with the space surrounding the aerodyne, in particular with the ambient atmosphere. By "outer shell" is thus meant the peripheral part of this structural element, delimited on the one hand by an external surface interfacing the external structural element with the space surrounding the aerodyne, and on the other hand by an internal surface. substantially parallel to the outer surface and close to this outer surface. By “close” is meant that a distance between the external and internal surfaces (called the thickness of the shell) is small compared to the surface dimensions, and for example less than 15% of the two surface dimensions of the external surface, and in specific embodiments less than 10%, 5% and 2% of these surface dimensions. The outer shell can have common structural properties along its thickness, in the sense that independently in particular of stress gradients, deformations or temperatures along the thickness (variations in mechanical or thermal properties), movements or inclinations of the outer surface correspond substantially to corresponding movements or inclinations of the inner surface and of the whole of the intermediate part.

By antenna "structurally dissociated" from the outer shell, it is meant that the antenna arranged inside the outer structural element is associated with a structure distinct from the outer shell, without being united. integrally with the outer shell, for example by incorporation or joining. The antenna thus comes under a separate and autonomous structure with respect to this outer shell. It can advantageously in particular be movable away from and / or inclined relative to the latter, at least for its installation and its maintenance.

By contrast, in an airplane wing such as for example disclosed in patent application CN 103887605, the array antenna forms with the honeycomb layers and the lower and upper panels which border it a single structure of the outer shell. composite constituting the upper covering or the lower covering, and are inseparably linked structurally. In particular, changes in the curvature of one of the panels or of one of the honeycomb layers affect the shape, positioning and orientation of the array antenna sandwiched between the honeycomb layers. bee and signs.

The configuration of the present description can be particularly advantageous, since it allows positioning and orientation of the antenna disconnected from the contours of the external structural element. This potentially offers great flexibility of implementation, which can prove to be invaluable in ensuring good radio connectivity with, in particular, satellites.

This configuration can also offer the advantage of allowing better protection of the antenna vis-à-vis external stresses, linked for example to difficult atmospheric conditions, to large temperature differences, or to shocks or micro- impacts.

What is more, the structural dissociation of the antenna and the outer shell is likely to greatly facilitate installation and maintenance operations.

The arrangement of antennas within an outer structural element with a bearing surface and with structural dissociation from the outer shell may prove to be surprising for a person skilled in the art. It goes against the apparently antagonistic imperatives of good aerodynamic behavior of the airfoil and efficient transmission of waves. radio. In fact, the external structural elements with a bearing surface generally include parts that disrupt the circulation of waves, in particular metallic ones, so that the only feasible solutions for associating them with antennas could appear as external positioning or integration on the surface - at the price of the disadvantages mentioned above.

Now, a remarkable characteristic of the aerodyne of the description is that at least part of the outer shells is substantially transparent to at least one range of radio frequencies, so that the antennas can receive and / or transmit radio waves through this. or these part (s) of the outer shells.

It is thus possible, in particular embodiments, to preserve the aerodynamic qualities of the aerodyne, which are often the subject of complex and expensive adjustments, while benefiting from a high efficiency of transmission and reception of the antennas. , including in directional terms. By preserving the aerodynamic qualities, it is in particular possible to limit the impact of drag and thus reduce fuel consumption. By placing the antennas inside the external structural element with a supporting surface, the antennas can also possibly be protected from disturbances due to existing electrical equipment.

The parts of the outer shells concerned by the substantial transparency can be made of materials suitable for this purpose, forming one body with other parts, for example metal, within the outer structural element. This could be, for example, a hood or a wing cap or a fin.

The radio frequency range (s) to which the parts of the outer shells are substantially transparent include in some modes at least one of the Ku (typically 12-18 GHz) and Ka (typically 26.5-40 GHz) bands.

In other modes, which may be combined with the previous ones for the same parts or other parts, the radio frequency range (s) at which the parts of the outer shells are substantially transparent include at least one cellular network frequency band, for example used for communications in 4G or 5G technology.

Different means of accessing the antennas arranged inside the external structural element, in particular for maintenance or updating operations, can be provided. In some embodiments, the outer structural member is removably mounted to the fuselage. In other embodiments, one or more parts of the external structural element are removable, and the antennas are accessible by removing this part or parts. In variants, hatches or flaps for accessing the antennas are provided in the external structural element.

In advantageous embodiments, the external structural element comprises at least one free space between the antenna (s) and the external shell (s).

Such free space can be used in particular to flexibly adjust the positioning or orientation of the antennas, during the installation of the latter or during maintenance operations.

In particular configurations:

at least one of the antennas is separated from the inner surface of the outer shell by at least 3 times the thickness of the outer shell, and in more specific embodiments at least 5 times, at least 10 times or at least 20 times this thickness;

at least one of the antennas is separated from the inner surface of the outer shell by at least 5 cm, and in more specific embodiments, at least 10 cm, at least 15 cm or at least 20 cm;

at least one of the antennas has an inclination which differs by at least 10 ° from an inclination of the inner surface closest to the outer shell, and in more specific embodiments, at least 15 °, at least 20 ° or at least 30 °; the inclination of the internal surface is defined by a perpendicular to this surface, and the inclination of the antenna by the main line of sight of the antenna, or if the antenna is flat, by a perpendicular to the plane of this antenna. According to particular embodiments, the aerodyne comprises at least one support structure carrying the antenna (s), this or these support structure (s) being arranged inside the external structural element while being structurally dissociated from the outer shell (s).

Such a support structure can in particular be fixed to the fuselage, for example by gluing.

According to particular embodiments, the aerodyne comprises at least one modem cooperating with the antenna (s) and arranged inside the external structural element.

The modem (s) and the antenna (s) can then be integrated on at least the same card. In a variant, the modem is arranged apart from the antenna with which it cooperates, and can be used centrally for several antennas positioned at separate locations and with different orientations, if applicable.

In some embodiments, the aerodyne having a horizontal plane (which can be defined for example as a plane perpendicular to a vertical plane of symmetry with respect to the wings), the antenna considered is oriented with an angle of inclination between 45 ° and 70 ° relative to this horizontal plane, and in particular implementations between 67 ° and 68 °, and more specifically still between 67.4 ° and 67.6 °.

The angle of inclination of the antenna is understood to mean the angle between a reference line of sight of the antenna and the vertical (an angle of 0 ° therefore corresponding to a horizontal positioning of a flat antenna).

In some embodiments, the antennas are at least two in number and the aerodyne comprises one or more multiplexer (s) configured to multiplex signals respectively obtained from these antennas.

In some modes, the antenna (s) includes (include) at least one transmission antenna and at least one reception antenna, these transmission and reception antennas being arranged on the same card and being spaced so as to avoid interference. full duplex cross interference. In advantageous embodiments, at least one of the antennas is an array antenna, the latter possibly being in particular phase-controlled. In particular embodiments, which can be combined with the previous ones, at least one of the antennas is a flat antenna.

In advantageous modes, the antenna (s) are electronically steerable. The absence of a rotating mechanical part for the antennas makes it possible to reduce the risk of breakdowns and the need for maintenance.

In a first type of antenna positioning choice, the external structural element is a dorsal fin and the antenna (s) are arranged in a lower part of this dorsal fin.

In a second type of antenna positioning choice, the external structural element is a dorsal fin and the antenna (s) are arranged in an upper part of this dorsal fin.

In a third type of antenna placement choice, the outer structural element is a wing.

These embodiments relating to the positioning of the antennas can be combined in all possible ways, some antennas being able for example to be placed in the dorsal fin, in the upper and / or lower part, and / or other antennas being able to be placed in one. or two wings. In particular, the antennas distributed at different locations on the aerodyne and in different orientations are likely to provide additional information, or to secure communications through deliberate redundancies.

In particular embodiments, the external structural element (s) is (are) composed at least partially of a material selected from polymer reinforced with carbon fibers or CFRP (for Carbon Fiber Reinforced Polymer), polymer reinforced with Kevlar fibers or KFRP (for Kevlar Fiber Reinforced Polymer), and polymer reinforced with glass fibers or GFRP (for Glass Fiber Reinforced Polymer).

The description also relates to an external aerodyne structural assembly comprising an external structural element with a lifting surface adapted to be mounted to a fuselage of an aerodyne and configured to provide the aerodyne with aerodynamic properties. This external structural element comprises at least at least one external shell and is provided with at least one antenna. According to the description, this or these antenna (s) is (are) arranged inside the external structural element while being structurally dissociated from this or these external shell (s). In addition, at least part of this or these outer shell (s) is substantially transparent to at least one range of radio frequencies, so that the antenna (s) can perform a chosen operation. among at least one reception and one emission of radio waves through this or these part (s) of the outer shell (s). Such an external structural assembly can thus be produced separately by integrating therein the desired antennas in an appropriate manner, and then be fixed to an aerodyne after, for example, packaging and transport.

Advantageously, it is suitable for an aerodyne conforming to any one of the embodiments described above.

The specification also relates to a method of arranging at least one antenna in an aerodyne comprising a fuselage and at least one external structural element with an airfoil mounted to the fuselage and configured to provide the aerodyne with aerodynamic properties. This external structural element comprises at least one external shell.

According to the description, the method comprises arranging the antenna (s) inside the outer structural element in a manner structurally dissociated from the outer shell (s). In addition, at least part of this or these outer shell (s) is substantially transparent to at least one range of radiofrequencies, so that this or these antenna (s) can perform a selected operation. among at least one reception and one emission of radio waves through this or these part (s) of the outer shell (s).

This method is advantageously suitable for producing an aerodyne conforming to any one of the embodiments above.

The description also relates to a method of arranging a set of antennas capable of transmitting or receiving in a radiofrequency range in an existing aerodyne implemented either during an initial operation. installation, or in a subsequent maintenance or updating operation, said method comprising the steps of:

dismantling at least one component of a structural element external to the airfoil of the existing aerodyne, the component being substantially transparent to the radio frequency range; installation of all antennas in an area cleared by dismantling the stage; adjustment of an electronic and electrical harness connecting the antenna assembly to a radio communication system and to a power supply inside the fuselage; reformation of the external structural element so as to cover the set of antennas in place.

The at least one dismantling component may be an aerodyne cowl. The installation step may include a step of fixing an antenna supporting structure on the fuselage. The reformation step may include a step of reassembling the dismantled component (s).

Presentation of figures

The invention will be better understood and other characteristics and advantages will appear more clearly in the light of the following description of exemplary embodiments, given without limitation with reference to the accompanying drawings in which:

[Fig. 1] FIG. 1 represents an airliner according to several embodiments making it possible to make it conform to an aerodyne according to the description

[Fig. 2] FIG. 2 is a block diagram functionally illustrating an operation with satellite communications of an aerodyne in accordance with a particular embodiment (antennas in the lower part of the dorsal fin);

[Fig. 3] FIG. 3 represents schematically and in a simplified manner an angular distribution of radiation from aerials in flight for an aerodyne of the type of FIG. 2;

[Fig. 4] FIG. 4 illustrates more precisely in cross section and in partial view an example of an arrangement of flat antennas in the lower part of the dorsal fin, corresponding to the mode of FIGS. 2 and 3; [Fig. 5] FIG. 5 shows in longitudinal section and in partial view the example of FIG. 4;

[Fig. 6] Figure 6 shows a side view of the components of a dorsal fin assembly, in which can be installed antennas according to the example shown in Figures 4 and 5;

[Fig. 7] FIG. 7 shows a lower part of the dorsal fin cover at the fuselage level, called a shoe, the latter forming part of the dorsal fin assembly of FIG. 6 and being intended to place antennas in accordance with the example Figures 4 and 5;

[Fig. 8] Figure 8 shows in the absence of the shoe of Figure 7 a corresponding fuselage area;

[Fig. 9] FIG. 9 shows the fuselage zone of FIG. 8 after fixing support legs by gluing;

[Fig. 10] Figure 10 shows in perspective a supporting structure configured for the positioning of antennas and intended to be installed in the fuselage area of Figures 8 and 9;

[Fig. 1 1] Figure 1 1 shows the fuselage area of Figures 8 and 9 after installation of the supporting structure of Figure 10 fixed on the support legs of Figure 9;

[Fig. 12] Figure 12 shows in perspective the fuselage area with supporting structure of Figure 1 1 after installation of panels for the attachment of flat antennas;

[Fig. 13] FIG. 13 represents in side view the fuselage zone with supporting structure equipped with the panels of FIG. 12;

[Fig. 14] FIG. 14 shows an example of a block of network antennas that can be used for an aerodyne according to the description, and more precisely in positioning in panels of a supporting structure such as those of FIGS. 12 and 13;

[Fig. 15] Figure 15 is an exploded view of the array antenna block of Figure 14;

[Fig. 16] FIG. 16 shows a functional architecture of radio communications, which can be used in particular in combination with one or more blocks of array antennas of FIGS. 14 and 15 in an aerodyne according to the description;

[Fig. 17] Figure 17 is a block diagram illustrating connections between four array antenna blocks of the type of Figures 14 and 15 in position and processing modems which may form part of the functional architecture of Figure 16;

[Fig. 18] FIG. 18 is a diagram of an electrical and electronic wiring harness within an aerodyne of the type of FIG. 2;

[Fig. 19] FIG. 19 is a photo showing an installation for testing network antennas such as for example those of FIGS. 14 and 15 in position in a shoe such as that of FIG. 7;

[Fig. 20] Figure 20 partially shows a variant of a supporting structure with network antenna blocks;

[Fig. 21] Figure 21 shows schematically in top view the supporting structure with array antenna blocks of Figure 20, in position in a shoe such as for example that of Figure 7;

[Fig. 22] FIG. 22 is a schematic illustration in cross section of different methods of installing antenna panels inside a shoe, in relation for example to FIG. 13 or to FIGS. 20 and 21;

[Fig. 23] Figure 23 shows schematically in cross section another method of installing antenna panels than those of Figure 22;

[Fig. 24] FIG. 24 is a block diagram functionally showing an aerodyne according to the embodiment of FIG. 2, with a different type of array antennas than those of the previous figures;

[Fig. 25] FIG. 25 is a block diagram functionally showing an aerodyne according to a particular embodiment distinct from that of FIG. 2 (antennas inside a wing on the fuselage side);

[Fig. 26] FIG. 26 shows a flowchart for implementing an antenna arrangement method according to the present description, in the context of an adaptation or maintenance of an operational aerodyne; [Fig. 27] FIG. 27 shows a flowchart for implementing an antenna arrangement method according to the present description, in the context of an aerodyne construction or transformation.

In the figures, identical or similar elements are designated by the same references. In addition, the suffixes "A" and "B" used for references conventionally specify elements as being located respectively on the right or left side of an aircraft in the direction of navigation.

Detailed description of embodiments

The present description illustrates the principles set forth so that a person skilled in the art is able to design various modalities which, although not explicitly described or shown, incorporate the principles of the description and are included in its spirit and scope.

All the examples and the conditional language set forth here are for explanatory purposes to help the reader understand the principles of the description and the concepts developed by the inventors to extend the state of the art, and should be interpreted as not being restricted. to such specifically described examples and conditions.

In addition, all statements reciting principles, aspects and embodiments of the description, as well as corresponding specific examples, are intended to cover both structural and functional equivalents. Such equivalents are also intended to include both known equivalents and equivalents that will be developed in the future, namely any developed elements that perform the same function, regardless of their structure.

Thus, for example, one of ordinary skill in the art will appreciate that the block diagrams presented herein provide conceptual views incorporating the principles of the specification. The terms "suitable for" and "configured for" are used in this specification to broadly cover initial configuration, subsequent adaptation, complement, or any combination thereof. An airplane 1 (FIG. 1), which may for example be an airliner such as that marketed under the brand A321 by the company Airbus, has an airframe including a fuselage 10 and wings 13 provided with covers 131 at their root for fixing to the fuselage 10, these cowls 1 31 being for example made of polymer reinforced with Kevlar fibers (KFRP) and contributing to the aerodynamic fairing of the wings 13 in addition to a main part 130, metallic. The aircraft 1 also comprises a tail unit including a dorsal fin 1 1 and horizontal stabilizers 12, the dorsal fin 1 1 being provided with cowls such as a lower cowl 1 1 1 at its zone of attachment to the fuselage 10, said shoe cover ("shoe cover" in English) a cover 1 12 at the upper end of the fin 1 1, called a "hood cover" in English, and an elongated cover in the upper part of the fin 1 1 and connecting the shoe 1 1 1 and the cap 1 12, said longitudinal cowl ("roof cover" in English), these cowls 1 1 1, 1 12 and 1 13 contributing to the aerodynamic fairing of the fin 1 1 in addition to a main part 1 10, metallic. The shoe 1 1 1 and the cap 1 13 are for example made of glass fiber reinforced polymer (GFRP).

The aircraft 1 is particularized by the presence of one or more antennas inside the fin 11 and / or at least one of the wings 13, and more precisely inside at least one of their parts consisting of the shoe 1 1 1 and the fin cover 1 12 and the wing covers 131, as detailed below.

It is understood that this list of parts of external structural elements with a bearing surface is not exhaustive, and that in alternative embodiments, antennas can be placed for example inside the longitudinal cover 1 12 made of GFRP.

In certain modes, antennas are present at various locations of the aircraft 1 and are operated jointly, for example by combined processing of signals obtained from these antennas and / or of transmitted signals. by these antennas. It is thus possible to enrich the transmission and reception capacities, in particular in terms of range, directional coverage and / or gain.

The operation of an antenna 2 inside the shoe 1 1 1 of the fin 1 1 in the aircraft 1 is for example carried out as explained below in relation to FIG. 2 (multiple antennas of the type antenna 2 which can be jointly active in the shoe 1 1 1). Inside the aircraft 1, the antenna 2 is integrated in an on-board communication system 5 also comprising a modem 6, an electronic and electrical network 51 1 of the aircraft 1, and a local wireless network (called LAN for “Local Area Network”) 512.

While the active antenna 2 is operating, the aircraft 1 communicates with a satellite 31 in reception (downlink 31 1, for example at 10 Gbit / s) and in transmission (up link 312, for example at 1 Gbit / s) , the satellite 31 being in radio link with a gateway parabolic antenna 321 on the ground, which is connected to a processing center 322 and via the latter to computer resources 323 (for example of the cloud or cloud type) and associated interfaces. The possible bandwidth depends above all on the capacities of the satellite (s) in connection with the aircraft.

Communications between aircraft 1 and satellite 31, a block diagram of which can be seen in Figure 3, is based on the transmission capacities via antenna 2 through the shoe 1 1 1 of the fin 1 1. The location of the antenna 2 can provide right 313A or left 313B sight lines (right and left being defined with respect to the direction of navigation) substantially perpendicular to the axis of the fuselage 10, and relatively wide angular radiation apertures. 314A or 314B respectively on the right and on the left (the representations of the radiation being purely of principle and not accounting for effective radiation patterns).

The combination of at least two antennas of the type of antenna 2 in the shoe 11 1, judiciously positioned and oriented, makes possible efficient radio communications both to the right and to the left of the aircraft 1, in accordance with the typical diagram of FIG. 3. A selection of active antennas can thus be carried out in particular as a function of a spatial positioning and directional of the airplane 1 with respect to communication satellites (in particular taking into account the azimuthal positions of these satellites with respect to the airplane 1).

Such an arrangement, illustrated in FIGS. 4 and 5, uses for example eight blocks of antennas including on the left four blocks of flat array antennas 21 1 B, 212B, 213B and 214B, and symmetrically on the right four blocks of array antennas plates not shown. These antennas are close in their upper part to a vertical plane of symmetry of the shoe 1 1 1, and are inclined by approximately 72 ° with respect to a horizontal plane (Figure 4), so that they have lines of sight elevated by about 18 ° relative to the horizontal of airplane 1 perpendicular to the axis of the fuselage 10.

The antenna blocks 21 1 B, 212B, 213B and 214B on the left and the corresponding ones on the right are carried two by two by panels 41 1 B and 412B on the left, and symmetrically on the right 41 1 A and 412A, which give the antennas the desired inclinations (Figure 5), and are articulated by means of hinges 42 to one or more structures not shown. For purely illustrative purposes, the panels 41 1 A, 412A, 41 1 B and 412B have dimensions in height and width of the order of 50 cm, and the antenna blocks of the right panels 41 1 A and 412A are spaced horizontally by a distance of between 45 and 50 cm (for example 47 cm, the same for the antenna blocks of the left panels 41 1 B and 412B).

A partition can be made between antennas for reception and transmission, the antenna blocks 21 1 B and 212B being for example used for transmission and the antenna blocks 213B and 214B for reception. The distance between the antenna blocks can then make it possible to operate in full duplex mode (called "full duplex" in English terminology), avoiding interference between reception and transmission.

The number and / or the size of the antenna blocks can be adapted as a function of the needs and of the available space, the examples presented in the present application not being limiting. A method of installing such antennas 2 inside the shoe 11 1 of an existing aircraft can be carried out for example as follows, with reference to Figures 6 to 13. In the absence of installation of the antennae 2, the shoe 1 1 1 is removably attached to the fuselage 10 and borders the main part 1 10, metal, of the dorsal fin 1 1, the longitudinal cover 1 13 being positioned on the main part 1 10 in the extension shoe 1 1 1 (figure 6). The shoe has, for example, a length of about 1.20 m (along the axis of the fuselage), and is mainly made of GFRP, adhesive film and honeycomb structure. For installation, the longitudinal cover 1 13 (figure 7) is removed, then the shoe 11 1 (figure 8) is removed, before fixing on the fuselage 10 (figure 9) support legs 421 ("brackets" in English, three in number in a triangle in the example shown), which will be used to fix a supporting structure 40 (FIG. 10). A simple gluing of the feet 421, as shown, may prove to be satisfactory for this purpose. The supporting structure 40 is configured to be fixed to the fuselage 10 on the one hand by countersunk parts 422 and on the other hand to the legs 421 respectively by fixing elements 423, and to receive panels which hold flat antennas, such as for example the panels 41 1 A, 412A, 41 1 B and 41 2B above. The supporting structure 40 is thus fixed to the fuselage 1 0 at a location provided for the shoe 1 1 1 (Figure 1 1). The panels 41 1 A, 412A, 41 1 B and 412B are then placed in position on the supporting structure 40 (figures 12 and 13), and after installation of the corresponding flat array antenna blocks, for example 21 1 B, 212B, 213B and 214B on the left side, in dedicated spaces 413 of the panels, and appropriate wiring (electrical and electronic), the shoe 1 1 1 can be replaced.

In appropriate configurations, all of these operations can prove to be particularly simple and economical to perform on existing aircraft. What is more, once the installation is done, the maintenance may require only limited effort, for example both for the maintenance of the antennas and the cabling and for that of the supporting structure 40.

More precisely, in examples with favorable conditions, it has been observed that all the operations can be carried out in less than 5 hours, access to the antenna positioning area and cabling being easy.

More details are given below on the configuration of the antennas 2 and their associated components, in specific exemplary embodiments. To this end, it will be noted that the local integration of functionalities associated with the antennas under the shoe 11 1 can be carried out to different degrees of complexity, while functionalities not locally integrated can be carried over inside the fuselage 10 by using an appropriate connection.

A block of antennas 20, as shown in Figures 14 and 15, for example comprises two sub-networks 221 and 222 of 256 elements ("patches" in English), and is identical in reception or transmission. This antenna block 20 can take the form of a printed circuit board or PCB (for "Printed Circuit Board"). In the present example, in which the antenna boards 201 are incorporated with other elements in an aluminum housing 202 with silicone seal 204 and covered with a plastic cover 203, modem functionality is reduced to controller boards. 206 (for antenna control and traceability), one or more modems being provided inside the fuselage 10 to perform the associated effective processing. The antenna block 20 also includes connectors 205, a ventilation assembly 207 (for cooling a passive metal plate) and a DC power supply brick 208.

The antenna block 20, and its two sub-networks 221 and 222, are multibeam, and are for example suitable for satellite communications both with satellites in geostationary earth orbit or GEO (for “Geostationary Earth Orbit”) and in low earth orbit or LEO (for "Low Earth Orbit"). The block of antennas 20 has for example a length (in the direction traversing the two sub-arrays 221 and 222) of between 46 and 47 cm, a width of between 42 and 43 cm, and a depth of the order of 5 , 5 cm. The assembly formed by the supporting structure 40 provided with the panels 41 1 A, 412A, 41 1 B and 412B and the antenna blocks 20 may have a relatively limited weight, for example of the order of 50 kg.

A radio communication system 50, cooperating with the antenna blocks such as the antenna block 20 above and installed inside the fuselage 10, for example mainly comprises the following elements, with reference to the architecture of principle shown in figure 16. In addition to a modem part 60, the radio communication system 50 includes:

a processing unit 71 comprising a digital signal processor or DSP (for “Digital Signal Processor”) subsystem, a processor or CPU (for “Central Processing Unit”) subsystem, a direct access controller to the memory or DMA (for "Direct Memory Access") and an external memory controller,

connectors 72 for connection to peripherals,

physical and data link layers (MAC layer for "Medium Access Control") 73 for communications with clients, including user interfaces, and

buses 74 interconnecting all the elements of the radio communication system 50.

The modem part 60 more specifically comprises a demodulation sub-part 601 (with parallel demodulation units) and a modulation sub-part 602, the demodulation being associated in reception upstream with analog-to-digital converters 603 and downstream with modules 605. for extracting data from transport trains by, in particular, decapsulation, and the modulation being associated in transmission upstream with modules 606 for preparing transport trains by, in particular, encapsulation and downstream with digital-to-analog converters 604.

The signals transmitted and received by the radio communication system 50 via the modem part 60 are for example satellite signals conforming to the DVB-S2 standard (standing for “Digital Video Broadcasting” - second generation for satellite broadcasting). In addition, the antenna blocks 20 and the modem part 60 can in particular be configured for transmissions in Ku and / or Ka bands. For example, the antenna blocks 20 are configured to receive and transmit in the Ku band, between 10.7 and 12.7 GHz in reception and between 14 and 14.5 GHz in transmission, with a transmission efficiency of around 80%. For example also, these antenna blocks 20 have in transmission an equivalent effective radiated power or EIRP (for "Effective Isotropy Radiated Power") of 32 dBW and in reception have a performance factor G / T (gain over noise temperature). of 3 db / K.

Also, antenna blocks 20 and modem part 60 can be configured to perform beamforming (also called beamforming) with phase and gain adjustment for each path, thereby providing multibeam capabilities. For example, up to 32 separate beams can be generated and up to 32 separate beams can be processed (32 signal inputs and 32 signal outputs), with a simultaneously processed signal bandwidth of 880 MHz (split between channels) . In other examples, up to 16 beams, or up to 8 beams can be processed.

By way of example, the antenna blocks 20 can use components developed by the company SatixFy such as a specialized integrated circuit or ASIC (for “Application Specifies Integrated Circuit”) for an active flat array antenna, marketed under the trademark “ PRIME ”, and an integrated component for radio frequencies or RFIC (for“ Radio Frequency Integrated Circuit ”), interfaced between a phased array antenna and a“ PRIME ”ASIC and acting as a front module, marketed under the brand“ BEAT ” .

Very schematically, as shown in Figure 17, the antenna blocks 20 provided to be arranged inside the shoe 1 1 1 are connected in series to two modems 621 and 622 provided to be placed inside the fuselage 10.

By way of illustration, an electronic and electrical wiring harness between the antennas 2 arranged inside the shoe 1 1 1 and the functions present inside the fuselage 10 may for example, as in figure 18, comprise an electronic path 51 for routing to one or more modems 62 (for example modems 621 and 622 above) and an electrical path 52 to a power supply electric 53 on the front of the device. A small diameter feedthrough near the antennas 2 at the fuselage 10, for example at a distance of between 1 m and 1.5 m, is sufficient to pass the appropriate wiring to a pressurized area without posing any particular difficulty, as known. a person skilled in the art. Inside the fuselage 10, the wiring path can for example pass through ceilings.

The power supply can be divided into several cables (for example four) in order to avoid too high amperage. Maximum values of around 12.5 A for amperage and 28 V direct current for voltage are, for example, observed.

The possible pre-existence of holes in the fuselage near the shoe 1 1 1, used in certain models of aircraft 1 for preliminary or periodic performance tests, makes it even easier to put the harness in place. Otherwise, the structure of the fuselage 10 can be pierced with minimal intervention and in a safe manner known to a person skilled in the art.

It can be noted that tests carried out in an anechoic chamber in reception and in transmission on examples of the type of those exposed above, as shown in the photo of FIG. 19, made it possible to establish the good resistance to radiation of antennas 2 when they are positioned inside a shoe 1 1 1, and to obtain relevant ranges of use in frequencies. The particular cases examined were the subject of measurements of ElRP in transmission and of received signal strength indicator and RSSI (for "Received Signal Strength Indicator") in reception, for waves with vertical or horizontal polarization, different angles of incidence, and various frequencies. The results obtained led to the observation of a radiation pattern preserved in the presence of the shoe 1 1 1 by comparison with measurements in its absence, with attenuation at different angles for different frequencies, and a satisfactory transparency of the shoe 1 1 1 for frequencies of the order of 1 1 GHz in reception and of the order of 14 GHz in transmission, a good compromise being obtained in transmission-reception with a common frequency of 1 1, 5 GHz (Ku band).

Tests were also carried out on the ground on moving vehicles with the lower part of the dorsal fin (shoe 1 1 1) mounted on the roof and the satellite links available, and thus confirmed the correct operation of the device under representative conditions.

In other embodiments of the antenna blocks, these directly incorporate substantial or complete functionality of modems. It is then no longer necessary to provide inside the fuselage 10 modems equipment such as those described above, and the harness can be simplified accordingly.

Another embodiment of a supporting structure than that explained above, shown schematically in Figures 20 and 21 and referenced 43, comprises two tilted right 431 A and left 431 B panels, joined in their upper part and arranged symmetrically with respect to a plane vertical in the axis of the fuselage 10. The supporting structure 43 is designed to receive four blocks of antennas of the type 20 described above, including two blocks of antennas 215A and 216A on the right panel 431 A, and two blocks of '215B and 216B antennas on the left panel 431 B.

Different configurations of a supporting structure of this type can be produced according to the present description, depending on the angles of inclination of such panels 431 A and 431 B with respect to the horizontal. Thus, principle illustrations show in Figure 22, in position inside the shoe 1 1 1, a supporting structure 441 with tilt angles of 45 °, a supporting structure 442 with tilt angles of 60 °, and suggest various intermediate inclinations of 48 °, 50 °, 52 °, 54 °, 56 ° and 58 ° respectively. In a particular embodiment, a supporting structure comprises a mechanism, for example based on notches or hooks, which makes it possible to adjust the inclination of the panels at different angles. This embodiment can be particularly advantageous for use in series of the same model of supporting structure, because it allows flexible adaptation of the configuration of this structure with several types of aerodynes, external structural elements chosen for the positioning of the antennas, categories of antennas, or radio communications applications.

In another embodiment, shown schematically in Figure 23, a supporting structure 45 has for its right panel 451 A and its left panel 451 B inclination angles of 70 °.

Other types of antennas than those described above are possible. For example, as shown in FIG. 24, with the aircraft 1 possibly being for example an airliner such as that marketed under the brand A330 by the company Airbus, a block of antennas 23 comprises on the right a flat array antenna 231 extended to the right, and to the left, a substantially square flat array antenna 232 and smaller in size than the array antenna 231 and spaced therefrom. The network antennas 231 and 232 are provided respectively for the reception and the transmission of radio waves, the reception being more demanding in performance than the transmission. The space between the antennas 231 and 232 helps prevent interference between transmission and reception in full duplex operation.

In another embodiment of the aircraft 1 (which may for example also be that marketed under the trademark A330 by the company Airbus) shown in FIG. 25, which can be combined with the preceding ones, antennas 2 are arranged inside 'at least one of the cowls 131 of the wings 13 in the vicinity of the fuselage 10. The antennas 2 are connected to one or more modems 6 dedicated to the combined processing of the corresponding signals.

The antennas operated in this configuration are advantageously small in size, compared to those that can be installed inside a fin as discussed above.

The radio communication systems 50 cooperating with the antenna blocks 2 can take any suitable form known to a person skilled in the art to perform the functions mentioned and produce the effects or results mentioned. They may in particular include devices, components, or physical parts of device (s) or component (s), which these parts be grouped together in the same machine or in separate machines, which can be separated within the aerodyne considered. Furthermore, the signal processing functionalities can be performed in the form of hardware, software, firmware (also called firmware), or any mixed form thereof.

The antennas 2 can for their part be arranged in any relevant area of the aircraft or in several of them, and the corresponding signals can be processed separately or jointly by means of the radio communication systems 50 in all technically feasible ways to achieve the functions mentioned and to produce the effects or results mentioned.

A method of arranging 81 a set of antennas in an existing aerodyne can be implemented either during an initial installation operation or in a subsequent maintenance or updating operation. Such a method 81 comprises for example the following steps, illustrated in FIG. 26:

first (step 81 1), disassembly of at least one component (such as a cover) from an external structural element with a bearing surface;

then (step 812), placing the set of antennas in an area cleared by the dismantling of step 81 1, for example by fixing an antenna supporting structure on the fuselage;

adjustment (step 813) of an electronic and electrical harness connecting the antenna assembly to a radio communication system and to a power supply inside the fuselage;

reforming (step 814) of the external structural element, for example by reassembling the dismantled component (s), so as to cover the set of antennas in place.

Such an installation of antennas in existing aerodynes is particularly advantageous, since it makes it possible, at lower costs and with reduced efforts, to transform aerodynes during operation in order to make them conform to the present description. A method of arranging 82 a set of antennas in an aerodyne under construction can be implemented separately in an external structural element with an airfoil before connection to the fuselage. Such a method 82 comprises for example the following steps, illustrated in FIG. 27:

first (step 821), clearing a placement area within the outer structural member, configured to receive at least one component (such as a cover) of that member;

then (step 822), placement of the set of antennas in this open area, for example by fixing an antenna supporting structure, and covering the set of antennas by placing the one or more components;

transport (step 823) of the external structural element to a construction site of an aerodyne;

attachment (step 824) of the outer structural member to a fuselage, during aerodyne construction operations;

adjustment (step 825) of an electronic and electrical harness connecting the set of antennas to a radio communication system and to a power supply inside the fuselage, possibly after dismantling the component (s) from the external structural element then reassembly after adjustments.

Such an installation of antennas upstream in elements intended for the construction of aerodynes is particularly advantageous, because it makes it possible to implement mass productions, for example of wings or fins, which can then be the subject of distribution or export to remote locations. It is thus possible to rationalize manufacturing and reduce fixed costs, while centralizing corresponding expertise.

Multiple other examples of antennas, radio communication systems, and placement configurations in external airfoil airfoil structural elements can also be developed while preserving the functionality discussed. The selection of these entities is advantageously carried out jointly, taking into account their interactions and the desired purposes. For example, positioning and the orientation of the antennas can be determined by means of supporting structures as a function of the number, capacities and types of operation, and of the possibly combined processing (in transmission and / or in reception) of these antennas.

In particular, although the antennas and radio communication systems described in the description are dedicated to satellite transmissions, they can also consist of antennas of radio communication systems configured for terrestrial transmissions, for example provided for receptions and transmissions. in 4G and / or 5G, particularly useful in particular when the aerodyne is on a tarmac. The joint presence of antennas intended for satellite and terrestrial transmissions in an aerodyne can be of particular interest. Other types of antennas than flat antennas and / or arrays can also be used.

On the other hand, in addition to the installation of antennas inside a shoe or a fin cap, or a wing cover at the level of their root for attachment to the fuselage, those- these can also be installed, for example (exclusively or in combination with some of the above arrangements) inside other parts of external structural elements having the desired transparency to the radio waves to be received or transmitted (longitudinal fin cover , horizontal stabilizer cowl, etc.). It may then be appropriate to provide an appropriate harness for electronic and electrical connections, or other means fulfilling similar functions.

In some embodiments, the antenna blocks are provided with a set of processing capabilities, particularly in terms of modems, which significantly reduce or make unnecessary additional processing performed remotely inside the fuselage.

Examples of antenna-carrying structures have been detailed in the description. However, all kinds of other supporting structures can be used, including mobile structures which can give the antennas orientations and / or positions that vary over time, in particular by remote control or prior programming. The supporting structures offer advantageously the possibility of applying to the antennas positions and / or orientations inside the external structural element with a supporting surface, without these positions and / or orientations being dictated by the external shell of the external structural element. Such a configuration can be implemented during the initial installation and / or during maintenance operations. In particular embodiments, the supporting structures are fixed to the fuselage and have no direct structural link with the external structural element which surrounds them. In other embodiments, the supporting structures have at least one connection with this external structural element, which can in particular form one or more complete links and / or pivot links. The supporting structures can be fixed and have adjustable flaps or panels, arms and / or fixing notches, making it possible to flexibly decide the position and orientation of the carried antennas, for example according to the capacities and the number of these and the missions to be carried out.

Based on the present specification and the detailed embodiments, other implementations are possible and within the reach of a person skilled in the art while remaining within the scope of the present invention. Specified elements can in particular be inverted or associated in any manner remaining within the scope of the present disclosure. Also, elements from different implementations can be combined, supplemented, modified, or deleted to produce other implementations. All of these possibilities are covered by this disclosure.

Claims

1. Method of arranging (81) a set of antennas capable of transmitting or receiving in a radiofrequency range in an existing aerodyne implemented either during an initial installation operation, or in a subsequent maintenance operation or updating, said method (81) comprising the steps of:

- dismantling (81 1) of at least one component of a structural element external to the bearing surface of the existing aerodyne, the component being substantially transparent to the radio frequency range;

- placement (812) of the set of antennas in an area cleared by the dismantling of step (81 1);

- adjustment (813) of an electronic and electrical harness connecting the antenna assembly to a radio communication system and to a power supply inside the fuselage;

- reformation (814) of the external structural element so as to cover the set of antennas in place.

2. Method (81) according to the preceding claim, wherein the at least one dismantling component is a cowl of the aerodyne.

3. Method (81) according to any one of the preceding claims, according to which the positioning step (812) comprises a step of fixing an antenna supporting structure on the fuselage.

4. Method (81) according to any one of the preceding claims, according to which the reforming step (814) comprises a step of reassembling the dismantled component or components.