EP0734093B1 - Feeding device for a multibeam array antenna - Google Patents

Description

The subject of the present invention is a device for feeding antennas multisources for the generation of multiple beams including partial or full recovery.

With such antennas, some regions angulars are covered by more than one beam. Each beam has a prescribed shape and contours, to optimize the gain depending on the direction and, also, in many cases, to limit interference.

The generation of Nb multiple beams at partial or total angular overlap can be performed from antennas with Ne sources or radiating elements, either direct radiation or indirect radiation, that is to say, illuminating an optic with one or more reflectors and / or lenses.

Each beam has a law optimal complex excitation for these sources. When the beams have angular overlaps between them, these optimal directivity excitation laws are only generally not "orthogonal".

By definition, two complex distributions a ₁ , a ₂ , a ₃ , ... a _Ne and b ₁ , b ₂ , b ₃ ... b _Ne are orthogonal if their complex scalar products:
p = Σ a _i xb _i * are zero whatever i is between 1 and Ne.

The beams corresponding to non-orthogonal distributions are also not orthogonal (see for example "A Variable Power Dual Mode Network .. "by H.S. Luh, IEEE Transactions - Volume AP 32 n ° 12 - December 1984 - page 1382-4). Their generation is consequently accompanied by losses in the circuits beam forming.

Four possibilities currently exist:

The first possibility I is to support these losses. By way of illustration, FIG. 1a shows a network antenna of this type at Ne = 8 radiating elements 11 and at Nb = 4 beams 10 using a matrix 13 called Non-orthogonal blass. This type of distributor is described for example in the book "Microwave Antenna Handbook" by Y.T. Lo and S.W. Lee, 1988 edition, p 19.10 and 19.11. On transmission, part of the power of one or several non-orthogonal beams is lost in the charges whose presence is necessary for the realization of non-orthogonal distributions desired.

The device of Figure 1a, shown here during transmission, normally operates with an amplifier beam, which limits flexibility in the distribution of power between beams.

Such flexibility can be obtained (see Figure 1b) by adding to the device of Figure 1a device called multi-port amplifier comprising a number of identical amplifiers, in number equal to that of the beams, and arranged between two distributors hybrids, for example constituted by matrices of Butler (described in the cited work "Microwave Antenna Handbook "by Y.T. Lo and S.W. Lee, 1988). that a Butler matrix is a passive network without losses theoretical comprising N inputs and N outputs, N being generally a power of 2. Its inputs are isolated between them, and a signal applied to any one of product inputs on all signal outputs of equal amplitudes, but whose phases vary linearly from one output to the next.

The resulting assembly has a structure complex and, although it produces the desired beams, it involves electrical losses after amplification which reduce yield performance.

The second possibility II is to generate "orthogonal" excitation laws corresponding to a distributor without electrical losses.

According to known techniques, these distributions can only be approached from those, non-orthogonal, desired, which translates into a degradation of the directivity of the radiation compared at the optimum and / or the level of the secondary lobes.

This is the case of antennas with shaped beams, having a reflector illuminated by an array of radiating elements, themselves supplied by a multimode type lossless distributor illustrated in FIGS. 2 a and 2 b . The distribution laws on the source network and corresponding to the beams are obtained by optimization from the desired radiation diagrams. However, to obtain a lossless distributor, the condition of orthogonality of the distributions must be added in the optimization which leads, according to known techniques, a reduction in directivity. Such antennas implementing a distribution network whose output signals are controlled only by the value of the phase of its phase shifting elements, are described for example in the article cited "A Variable Power Dual Mode Network .." by HS Luh , IEEE Transactions AP 32 N ° 12 - December 1994-pages 1382-1384.

The devices of FIG. 2 a and of FIG. 3 a , shown on transmission, with respectively lossless dies of the Blass type and dies in cascade, operate normally with a beam amplifier, which limits the flexibility in the distribution of power between beams. Note that a cascade matrix is described in the article "On Multimode Antenna Concepts" by La Flame et al - ESA Workshop on Advanced Beam Networks - ESA WPP-030 (1991) (figs. 3 and 4).

Identical performances are obtained by so-called "diagonalization" matrices (see G. Ruggerini, "The diagonalization BFN ...", ICAP proceedings 1973, pages 570-573).

Such flexibility can be achieved by adding to those of FIGS. 2a and 3a, a device known as multi-port amplifier with number identical amplifiers, equal to that of the beams, between two hybrid matrix type distributors Butler (described in the cited work of Lo and Lee page 19.9).

The resulting devices, shown in FIGS. 2 b and 3 b , are complex and, although they do not involve losses after amplification, produce only approximate distributions giving beams with non-optimal performance.

The third possibility III is to use an active antenna.

In an active antenna, a module amplifier is connected to each radiating element.

This type of antenna can include a direct radiation, as shown in Figure 4 to the emission, or be an illuminated reflector antenna by a network of the same type.

The distribution losses corresponding to the non-orthogonality of the optimal laws are compensated here by a distributed amplification, introduced between the loss circuits and radiating sources.

On issue, the problem here is that the laws desired optimal distribution are usually only not uniform, especially if level control side lobes is required. This non-uniformity leads to different output levels for them power amplifiers resulting in a efficiency (radio power / power continuous supply) not maximum, and consumption very high.

Optimization of only phases, to avoid this problem does not get distributions and degrades performance, especially the lateral lobe control.

At reception the problem is the high number required low noise amplifiers (one per element radiating and not one per beam).

The fourth possibility IV is to use a semi-active antenna called multimatrix.

A semi-active antenna is a distributed amplification - not centralized - where a lossless hybrid distributor is introduced between amplifier modules and radiant elements for y control the power distribution.

A semi-active multimator antenna is a semi-active antenna where this lossless hybrid splitter consists of a multiplicity of distributors smaller hybrids at 2x2, 3x3, 4x4, 6x6, 8x8 ... doors, identical or not, connected to the radiating elements in a way that depends on the type of beams to beget. In addition, the beams can be modified there, if necessary, by acting on low phase shifters level. Such a multimating power supply device is described for multisource reflector antennas, in French Patent N ° 89 12584 filed by Applicant on September 26, 1989 and published on March 29, 1991 under No. 2,652,452 and whose inventor is A. Roederer, and for direct radiation networks, in French Patent N ° 91,01086 filed by the Applicant on January 31, 1991 and published on August 7, 1992 under N ° 2 672 436, and the inventors of which are A. Roederer and C. van't Klooster. It allows by optimization, for each beam, of the phases of signals before amplification, to get beams neighbors of those requested. Such a system allows to generate without loss distributions (beams) no orthogonal. However, since only the phases at the input are optimized, and that the dispatcher is simplified by the use of small distributors multiple, optimal distributions cannot be than approximate. This results in a loss of directivity typically between 0.5 and 1 decibel.

In practice :

The first solution I is rarely used cause electrical loss.

The second solution II is the most used, often with only two beams (or modes) and with a separate amplification system for each channel multiplexed on each beam (figure la), but sometimes also in combination with a multi-port amplifier, for example for US-Canada M-SAT satellites (see "M-SAT L-Band Antenna Subsystem ", by S. Gupta, proceedings of JINA'94 Symposium, page 197). Training matrices of beams are orthogonal and this results in a loss directivity typically between 0.5 and 1.5 dB compared to the ideal case where each beam would be generated from a separate antenna with the law optimal for the corresponding beam (ideal case).

Solution III, i.e. an antenna active, is successfully used for speed cameras, where it is the product of emission-reception diagrams (beams) and not each of these diagrams that matters. In this case, while keeping the amplitudes uniform on transmission, there are phases on transmission and reception and reception amplitudes for optimization.

Solution IV, that is to say a semi-active multimating antenna, may prove to be more efficient than the previous one, but, as indicated above, it does not however lead to the desired optimal distributions, (except exceptional case where these happen to be achievable exactly by such a configuration).

The subject of the present invention is a feed device for a multisource antenna multiple beams which eliminates losses of directionality mentioned above while avoiding losses in high level circuits.

A first object of the invention is thus to achieve exactly and without losses, and with a distributed and uniform amplification, the distributions non-orthogonal excitation prescribed, with a semi-active antenna, either direct radiation or indirect radiation.

A second object of the invention is to make possible the choice of an Na number of amplifiers which is different from the number Nb of the beams and / or the number Do not radiant elements (or sources), while in the semi-active prior art antennas, the number Na of amplifiers is necessarily equal to the number Do not radiant elements.

A third object of the invention is to make possible adjustment of the power distribution between beams, depending on the fluctuations in traffic or propagation conditions, while maintaining total power consumption minimal.

a) un dispositif formateur de faisceaux à bas niveau divisant Nb signaux d'entrée de faisceaux en fonction de caractéristiques de couverture recherchées et, après déphasage, combinant ceux-ci pour former, sur ses Na sorties, Na signaux de sortie, ledit dispositif formateur de faisceaux ayant une matrice de transfert non-orthogonale,

b) Na modules amplificateurs amplifiant, en mode d'émission, les Na signaux de sortie,

c) un répartiteur de puissance de sortie disposé entre les Na modules amplificateurs et Ne éléments rayonnants, et ayant une matrice de transfert orthogonale

   caractérisé en ce que Nb ≤ Na ≤ Ne, et en ce que la matrice de transfert orthogonale du répartiteur de puissance est telle qu'elle permet le passage entre, d'une part, Nb distributions à l'entrée du répartiteur de puissance, dont l'amplitude des Na signaux est sensiblement égale pour chacun des Nb faisceaux et dont la phase des Na signaux satisfaisait au moins la condition d'une égalité des produits scalaires complexes pris deux à deux des Nb vecteurs d'excitation à l'entrée du répartiteur de puissance, et des produits scalaires complexes pris deux à deux des Nb vecteurs d'excitation de sortie correspondants, et d'autre part Nb distributions de sortie pré-déterminées.The first object as well as possibly the second and / or the third object of the invention are obtained by a device for supplying a multi-beam multisource semi-active antenna, of the type comprising successively:

a) a low level beam forming device dividing Nb beam input signals as a function of desired coverage characteristics and, after phase shift, combining these to form, on its Na outputs, Na output signals, said forming device beams having a non-orthogonal transfer matrix,

b) Na amplifier modules amplifying, in transmission mode, the Na output signals,

c) an output power distributor arranged between the Na amplifier modules and Ne radiating elements, and having an orthogonal transfer matrix

characterized in that Nb ≤ Na ≤ Ne, and in that the orthogonal transfer matrix of the power distributor is such that it allows the passage between, on the one hand, Nb distributions at the input of the power distributor, of which the amplitude of the Na signals is substantially equal for each of the Nb beams and whose phase of the Na signals satisfied at least the condition of equality of the complex scalar products taken two by two of the Nb vectors of excitation at the input of the distributor power, and complex scalar products taken two by two from the corresponding Nb output excitation vectors, and on the other hand Nb predetermined output distributions.

The device according to the invention thus allows optimize both the phases and the amplitudes of distributions, and therefore avoid directivity losses linked to the approximate distributions of Prior Art.

In a manner known per se, at the entrance to the power distributor, signal phases corresponding to one of the Nb distributions can be null.

The dispatcher can include at least one directive module comprising a directive coupler with two inputs and two outputs and having a ratio of directivity r given, and an associated phase shift element coupled to an output of the directional coupler.

In the absence of special conditions for the beams (symmetry, etc.), the distributor output power at Na inputs and Ne outputs includes in general [(Ne - 1) + (Ne - 2) + ... + (Ne - Na)] directive modules.

The invention is particularly applicable to the case where the number Na of the amplifier modules is equal to number Nb of beams.

According to a first variant, the device is characterized in that Nb = Na = Ne = 2 and in that the power distributor includes a directive module comprising a said directional coupler having a ratio of directivity r given, whose inputs are coupled to amplifier module outputs and one element phase shifter disposed between the directional coupler and one of the two radiating elements, the other outlet of the coupler directive being directly connected to the other element radiant.

According to a second variant, the device is characterized in that Nb = Na = 2, in that Ne ≥ 4, and in that the power distributor has at least five directive modules each of which has a coupler directive having a given directivity ratio r, of which the inputs constitute the inputs of the directive module and which has a phase shift element at a first output associated with it. It can preferably include five modules and it is then characterized in that it comprises five directive modules, namely a first module directive having an input connected to the output of a first amplifier module and having its first and second outputs connected to an input respectively a second and a third directive module, the third directive module also having a second input connected to the output of a second module amplifier, the first and second outputs of the second directive module being connected to a first input respectively of a fourth directive module and a fifth directive module, the first and second outputs of the third directive module being connected to a second entry respectively from the fifth and the fourth directive modules and the outputs of the fourth and fifth directive modules being each connected to a radiant element.

It can be characterized in that the ratio directivity r of the first directional coupler of the first directive module and the phase shift of the phase shifter element associated with it are such that in the mode reception, the power at the two entrance doors of the first directive module is the same for each of the two beams, in that the directivity ratio r of directional couplers of the fourth and fifth modules directives, and the phase shifts of their phase-shifting elements associated are such that the power corresponding to first beam is concentrated in reception mode to only one of their front doors, in that the ratio r of the phase shift element of the third module directive and the phase shift of the associated phase shift element are such that the power corresponding to the first beam is concentrated towards its second entry and in this that the directivity ratio r of the directional coupler of first and second directive modules and phase shifts of their associated phase-shifting elements are such that the second beam output power is concentrated in reception mode to only one of their doors entry.

According to a third variant particularly advantageous, the device is characterized in that Nb = Na = 2, in that Ne = 8, and in that the distributor directive has nine directive modules each of which has a directional coupler having a ratio of directivity r given, whose inputs constitute the directive module inputs and presenting at a first output a phase shift element associated with it, the output of the associated phase-shifting element constituting the first output of the directive module, a first, second, third and fourth output directive modules having their outputs each connected to a radiating element, an input directive module having its inputs connected at the outputs of amplifier modules, and a first, second, third and fourth directive modules intermediaries being arranged in cascade, the first intermediate directive module having an input coupled to the second output of the input directive module, its first and its second outputs being coupled respectively to an entry in the fourth directive module output and to an input of the second directive module intermediate, the second intermediate module having a input coupled to the first output of the directive module input and having its first and second outputs coupled respectively to an input of the fourth module output directive and input of the third module intermediate directive, the third directive module intermediate having its first and second outputs coupled respectively to an input of the fourth module intermediate directive and at an entrance to the third output directive module and the fourth directive module intermediate having its first and second outputs coupled respectively to an input of the second and the first output directive modules. According to a mode of preferred embodiment of this variant, the ratios r of output couplers and second, third and fourth intermediate directive modules as well as phase shifts of the phase-shifting elements associated with them are chosen to concentrate the power corresponding to a directional beam towards only one of their doors input, while the ratio r of the directional coupler of the first intermediate directive module and the phase shift of the phase shift element associated with it are such that they -concentrate the power corresponding to a non-beam directive to only one of their front doors, and that the ratio r of the directional coupler of the phase shift module input and the phase shift of the phase shifter element which is associated are such that the powers are the same for the two beams at the inputs of the phase shift module input and therefore on the module outputs amplifiers.

According to a variant corresponding to the case where Nb ≠ Na, the device can be characterized in that Nb = 2, Na = 4 and Ne = 4 and in that it includes a first and second upstream directive modules whose inputs are each connected to an output of a module amplifier as well as first and second modules downstream directives whose outputs are connected to radiating elements, in that the first and the second outputs of the first upstream directive module are connected respectively to an entry of the first and the second downstream directive modules and in that the first and the second outputs of the second upstream directive module are connected respectively to an input of the second and the first downstream directive modules. It can then be characterized in that the ratio r and the phase shift of the first and second downstream directive modules are such that in reception mode, the amplitudes of the signals on each of their entries are equal, for each of two incident beams, and in that the ratio r and the phase shift of the first and second directive modules upstream are such that in reception mode, the amplitudes of signals on their inputs are equal, for each of two incident beams.

The invention also relates to a distributor of power which is preferably usable in the frame of the above feeder. This power distributor has a plurality of directive modules comprising a directive coupler having two inputs and two outputs and presenting, in the case of a directive module of a first type, an element phase shifter arranged at only one of the two outputs of said directional coupler, the output of the phase shifter constituting the output from the module, and in the case of a directive module of a second type, a phase-shifting element arranged at each of the two outputs of the directional coupler, the outputs of phase shifters constituting the module outputs.

It has a cascade arrangement symmetrical and without crossing including a line control unit comprising at least one directive module of the second type, this central line being surrounded symmetrically of at least one left line and at least a straight line of directive modules of the first type arranged in cascade without crossing, at least two directive modules of the first type constituting modules entry having at least one entry constituting the Na inputs of the power distributor, and it presents directive modules of the first type constituting modules output and having at least one output connected to a input of Ne antenna elements.

Advantageously, the directive modules of the first type which are arranged on the same side, respectively left or right with respect to said line central, have their phase shift element arranged in the respectively left or right output of their coupler directive.

Advantageously, the directive modules of the first type which are neither input modules nor output modules, and which are located on the left side by compared to said center line have at least their entry right connected to the left output of a directive module upstream, and vice versa by symmetry for said modules located on the right side.

Advantageously, the directive modules of the first type which are neither input modules nor output modules, and which are located on a line extreme left with respect to said center line, have their left input connected to the left output of a upstream directive module, and their right input connected to the left output of another upstream directive module, and conversely by symmetry for said modules located on the right side.

At least one phase shift element can be variable, so as to allow reconfiguration to less partial of the beams.

The output power distributor can advantageously include a plurality of modules phase shifters, including at least one input module whose inputs are connected to module outputs amplifiers and the directivity of the module (s) input is such that, for each beam, the powers on each of the inputs of the module (s) input phase shifters are the same, while the other phase shift modules do not meet this condition.

The beam forming device can operate at an intermediate frequency with respect to the device transmit / receive frequency, and it then has, at each of its Na outputs, a frequency converter, so as to allow a appropriate frequency change.

The beam-forming device can, in variant, operate at the transmission / reception frequency of device.

The beam-forming device can be a digital circuit comprising, at the output, digital to analog converters.

Said equality between the amplitudes of the Na signals for each of the Nb beams can be achieved exactly or by tolerating a slight ripple, of the order of ± 1 dB between the Na signals, which does not ultimately degrade the directivity performance.

The invention also relates to an antenna characterized in that it comprises a device for focusing comprising at least one reflector and / or at minus a lens, and a feeding device such as defined above, the Ne radiating elements which are associated being positioned relative to the device focus to get focus at transmission and / or reception.

a) un dispositif formateur de faisceaux à bas niveau divisant Nb signaux d'entrée de faisceaux en fonction de caractéristiques de couverture recherchées et combinant ceux-ci pour former, sur ses Na sorties, Na signaux de sortie, ledit dispositif formateur de faisceaux ayant une matrice de transfert non-orthogonale,

b) Na modules amplificateurs amplifiant, en mode d'émission, les Na signaux de sortie,

c) ledit répartiteur de puissance de sortie qui est disposé entre les Na modules amplificateurs et Ne éléments rayonnants, et ayant une matrice de transfert orthogonale

   caractérisé en ce qu'il comporte les étapes suivantes ; avec Nb ≤ Na ≤ Ne :

• imposer aux Na amplitudes des distributions à l'entrée dudit répartiteur de puissance d'être égales pour chacun des Nb faisceaux ;
• en déduire Nb (Nb-1) égalités des produits scalaires complexes pris deux à deux, des Nb vecteurs excitation complexes à l'entrée du répartiteur et des Nb vecteurs excitation de sortie ;
• déterminer, directement ou par un programme d'optimisation, les phases des signaux d'entrée ;
• en déduire la fonction de transfert du répartiteur.

Finally, the invention relates to a method for determining the transfer function of the output power distributor of a supply device for a multi-beam multisource semi-active antenna, of the type comprising successively:

a) a low level beam forming device dividing Nb beam input signals as a function of desired coverage characteristics and combining these to form, on its Na outputs, Na output signals, said beam forming device having a non-orthogonal transfer matrix,

b) Na amplifier modules amplifying, in transmission mode, the Na output signals,

c) said output power distributor which is arranged between the Na amplifier modules and Ne radiating elements, and having an orthogonal transfer matrix

characterized in that it comprises the following stages; with Nb ≤ Na ≤ Ne:

• requiring the Na amplitudes of the distributions at the input of said power distributor to be equal for each of the Nb beams;
• deduce Nb (Nb-1) of the scalar products taken two by two, Nb complex excitation vectors at the input of the distributor and Nb excitation vectors output;
• determine, directly or through an optimization program, the phases of the input signals;
• deduce the transfer function of the dispatcher.

The power distributor can advantageously include [(Ne - 1) + (Ne - 2) + ..... (Ne - Na)] directive modules.

• les figures 1a et 1b représentent une antenne multimodes à perte, les figures 2a et 2b une antenne multimodes à matrice de Blass, les figures 3a et 3b une antenne multimodes à matrice en cascade, la figure 4 une antenne réseau active, et la figure 5, une antenne multimatrices semi-active, ces antennes, appartenant à l'Art Antérieur, ont été présentées ci-dessus ;
• la figure 6 représente un schéma d'une antenne semi-active selon la présente invention ;
• la figure 7 représente un mode de réalisation de l'invention dans le cas où Ne = Na = Nb = 2 ;
• les figures 8 et 9 représentent respectivement un mode de réalisation et un mode de réalisation particulièrement avantageuse de l'invention dans le cas où Ne = 4, et Na = Nb = 2 ;
• la figure 10 représente un mode de réalisation de l'invention dans le cas où Ne = = 8, et Na = Nb = 2 ;
• les figures 11a et 11b représentent deux modes de réalisation de l'invention, correspondant au cas où Nb = Na = 4 et Ne = 8, respectivement avec une matrice en cascade et avec une matrice de Blass ;
• la figure 12 représente une variante de réalisation de la figure 6 correspondant au cas où Nb = 2, Na = 4 et Ne = 8 ;
• la figure 13 représente un mode de réalisation de l'invention dans le cas où Ne = 4, Na = 4 et Nb = 2.
• les figures 14 à 17 représentent la couverture de quatre faisceaux (Nb = 4) à partir d'une antenne de satellite géostationnaire à Ne = 24 sources, respectivement "Pan Européen", "GB/Europe", "IT/Europe" et "Espagne/Europe" ;
• les figures 18 et 19 illustrent un mode de réalisation préféré de la disposition des 24 sources SI à S24 et de la géométrie de l'antenne, en vue de produire les quatre faisceaux précités.
• la figure 20 représente un mode de réalisation préféré d'un répartiteur de puissance selon l'invention.

Other characteristics and advantages of the invention will appear better on reading the description which follows, given by way of nonlimiting example, in conjunction with the appended drawings, in which:

• FIGS. 1 a and 1 b represent a multimode antenna at a loss, FIGS. 2 a and 2 b a multimode antenna with a Blass matrix, FIGS. 3 a and 3b a multimode antenna with a cascade matrix, FIG. 4 an active network antenna , and FIG. 5, a semi-active multimator antenna, these antennas, belonging to the prior art, have been presented above;
• FIG. 6 represents a diagram of a semi-active antenna according to the present invention;
• FIG. 7 represents an embodiment of the invention in the case where Ne = Na = Nb = 2;
• Figures 8 and 9 respectively represent an embodiment and a particularly advantageous embodiment of the invention in the case where Ne = 4, and Na = Nb = 2;
• FIG. 10 represents an embodiment of the invention in the case where Ne = = 8, and Na = Nb = 2;
• Figures 11a and 11b show two embodiments of the invention, corresponding to the case where Nb = Na = 4 and Ne = 8, respectively with a cascade matrix and with a Blass matrix;
• FIG. 12 represents an alternative embodiment of FIG. 6 corresponding to the case where Nb = 2, Na = 4 and Ne = 8;
• FIG. 13 represents an embodiment of the invention in the case where Ne = 4, Na = 4 and Nb = 2.
• Figures 14 to 17 show the coverage of four beams (Nb = 4) from a geostationary satellite antenna at Ne = 24 sources, respectively "Pan European", "GB / Europe", "IT / Europe" and " Spain / Europe ";
• FIGS. 18 and 19 illustrate a preferred embodiment of the arrangement of the 24 sources SI to S24 and of the geometry of the antenna, with a view to producing the aforementioned four beams.
• FIG. 20 represents a preferred embodiment of a power distributor according to the invention.

The device according to the invention is intended for feeding multiple element beam antennas multiple radiant, of which the prescribed beams are partially cover and which consequently corresponding excitation distributions of these elements are not orthogonal, i.e. their complex dot products are not zero.

The devices according to the invention can be used during transmission and / or reception.

The antenna will mainly be described in transmission mode but all of the lessons can be transposed, mutatis mutandis, to reception operation by simple application of the principle of reciprocity, the structure of the circuits and their links remaining the same, but the signal traveling from the antenna array to the transmit / receive circuits instead of traveling in the opposite direction. Of course, the amplifier stages, which are placed in the same places, are, in this case, low noise amplifier stages whose input is located on the antenna side and the output on the transmit / receive circuit side. The two types of amplifiers (power amplifiers for transmission and low noise amplifiers for reception) can also coexist in the same module, with appropriate switching or duplexing.

By convention, and for the purpose of simplification, we will define the "inputs" and "outputs" of each circuit (or stage, or module) in fictitiously considering that the antenna is in mode resignation. In other words, "inputs" and "outputs" of each circuit (stage, or module), such as defined above, will actually fulfill the functions outputs and inputs respectively if the antenna would actually be in reception mode.

The device according to the invention comprises a microwave hybrid distributor whose structure is fundamentally different from that of devices usual. This design allows in particular, and unlike existing systems, to choose will the number of Na amplifiers, which can be different from the number Nb of the beams and / or the number Ne radiant elements. The device of the invention is, in general, illustrated by Figure 6.

Ne radiating elements 61 to radiation direct, or illuminating an optical system 1, are connected by lines 62, to a hybrid microwave distributor 63 without losses, at Ne x Na doors (Ne exit doors and Na entrance doors). The Na entrance doors are connected to the outputs of Na amplifier modules 64. The inputs of amplifiers 64 are connected to a 65 phase shifting distributor with losses having Na x Nb doors. This phase shifting distributor 65, which constitutes a device low level beam former, has Na combiners 66 each with 1 x Nb doors (1 exit door and Nb entry doors), NaxNb phase shifters or sections of line 67, and Nb dividers 68 arranged between doors 69 Nb beams and phase shifters 67 of each beam. Each divider 68 has Na x 1 doors. The device can operate on transmission, reception or both modes at the same time, adapting the modules to each case amplifiers 64. FIG. 7 illustrates the implementation the simplest possible device of the invention with Ne = Na = Nb = 2. The amplifier modules are here of the type transmission / reception.

Figures 8 and 9 illustrate another layout in simple operation of the device of the invention with Ne = 4, Na = Nb = 2, Figure 9 constituting a simplified variant in Figure 8.

Figure 10 illustrates another implementation simple device of the invention with Ne = 8, Na = Nb = 2.

The configurations in Figures 7 to 10 are discussed in more detail in the next section.

FIGS. 11 a and 11 b illustrate in more detail two embodiments where the distributor is of the cascade type ref. 103, (fig. 11 a ) or Blass type ref. 103 '(fig. 11 b ), for the generation, here on emission, of Nb = 4 non-orthogonal beams with overlaps. The distributor 103 includes 24 directive modules which are interconnected as shown in FIG. 11 a . The distributor 103 'has 22 interconnected modules as shown in Figure 11b .

• Ne éléments rayonnants 101 reliés à des lignes de transmission 102 et illuminant un réflecteur 1,
• un répartiteur micro-ondes 103 ou 103' à Na entrées et à Ne sorties, avec Nb ≤ Na ≤ Ne, nominalement sans pertes et à matrice de transfert orthogonale dont les Ne sorties sont connectées au Ne éléments rayonnants 101 par des lignes de transmission 102.

The device (here with Ne = 8, Na = 4 and Nb = 4) includes:

• Ne radiating elements 101 connected to transmission lines 102 and illuminating a reflector 1,
• a microwave distributor 103 or 103 ′ with Na inputs and Ne outputs, with Nb ≤ Na ≤ Ne, nominally lossless and with an orthogonal transfer matrix, the Ne outputs of which are connected to the Ne radiating elements 101 by transmission lines 102 .

Each of the Nb beams prescribed emanates from all or part of the Ne elements with a distribution amplitude and phase specific which is optimized for each beam as if the antenna should not generate that this beam. Such optimization is done using conventional optimization programs such as minimax or multiple projections, known procedures specialists (see for example the book "The Handbook of Antenna Design ", edited by A. Rudge et al., 1986, p 263).

A microwave distributor 63 (fig. 6) according to the invention typically consists of couplers hybrids (which are generally not at 3 decibels), associated with fixed phase shifters or sections of line or waveguide, these components being connected in cascade by lines or waveguides. The dispatcher 63, called orthogonal or multimode, is from the family of those used for example for multimode antennas with conventional shaped beams (from case II of section previous).

Freedom to choose the number of amplifiers Na, between the number of achievable beams Nb and the number of radiating elements Ne, represents a new important possibility. In existing systems, Na is always either the number Nb of the beams, in the case passive systems (fig. la, 1b, 2a, 2b, 3a, 3b), or to the number Ne of radiating elements in the case of active systems (fig. 4), or semi-active systems (fig. 5).

The function of the power distributor 63 set implemented according to the invention, is to match exactly at Nb distributions given at Ne level radiating elements, and generally not orthogonal, Nb distributions at Na entry doors, all at equal amplitudes with Nb≤Na≤Ne.

Hybrid microwave splitters are unable to fulfill this function when prescribed distributions are not orthogonal.

The distributor 63 presents a matrix of transfer exactly matching said distributions between them, and which is determined in implementing the following design rules.

a) la matrice de transfert du répartiteur de puissance de sortie doit être orthogonale (nominalement sans pertes). Les produits scalaires des Nb vecteurs excitations complexes à l'entrée du répartiteur pris deux à deux sont égaux à ceux, connus, des Nb vecteurs excitations de sortie correspondants, de manière à respecter cette condition. Pour chacun des Nb faisceaux, on impose que les Na amplitudes des distributions à l'entrée du répartiteur soient égales. Il reste donc Na x Nb phases d'entrée à déterminer. Les phases de la première distribution peuvent être rendues nulles par intégration d'un déphaseur à chaque entrée du répartiteur. Il reste donc Na x [Nb-1] phases d'entrée à déterminer. Les égalités de produits scalaires complexes deux à deux fournissent 2x Nb! / [[Nb-2]!x2!] = Nbx [Nb-1] équations permettant de déterminer par un programme d'optimisation classique dans le domaine technique de l'invention, les Nax[Nb-1] phases voulues des signaux d'entrée tant que Nb<Na, et de manière unique, donc par calcul sans qu'il soit besoin d'utiliser un programme d'optimisation, si Na=Nb.

b) On connaít donc Nb distributions à l'entrée du répartiteur par exemple 63, et les Nb distributions de sortie correspondantes, données au départ. La détermination de la matrice de transfert du répartiteur de sortie 63 transformant Nb vecteurs complexes d'entrée connus à Na composantes en Nb vecteurs de sortie connus à Ne composantes est unique dans le cas où Nb=Na, c'est-à-dire si le nombre d'amplificateurs est égal au nombre de faisceaux. On remarque que ce cas particulier est favorable puisqu'il permet, pour un système semi-actif, de diminuer le nombre Na des amplificateurs, étant entendu que le nombre Ne des éléments rayonnants est en général supérieur, voire très supérieur au nombre Nb des faisceaux. Il suffit, pour déterminer cette matrice, d'écrire les Nb équations complexes de transfert pour chacun des Nb vecteurs, ce qui fournit NbxNb équations complexes à partir desquelles la détermination des NbxNb coefficients complexes de la matrice de transfert correspondant à la fonction de transfert du répartiteur est unique. Ce calcul relève de l'algèbre matricielle classique.

After determination, at the level of the radiating elements, of the Nb optimal distributions (or "output vectors") corresponding to the Nb prescribed beams, its design is carried out in two stages described below:

a) the transfer matrix of the output power distributor must be orthogonal (nominally lossless). The scalar products of the Nb complex excitation vectors at the input of the distributor taken two by two are equal to those, known, of the corresponding Nb excitation output vectors, so as to meet this condition. For each of the Nb beams, it is necessary that the Na amplitudes of the distributions at the input of the distributor are equal. There therefore remains Na x Nb input phases to be determined. The phases of the first distribution can be made null by integration of a phase shifter at each input of the distributor. There therefore remains Na x [Nb-1] input phases to be determined. Equations of complex dot products two by two provide 2x Nb! / [[Nb-2]! X2!] = Nbx [Nb-1] equations making it possible to determine by a conventional optimization program in the technical field of the invention, the Nax [Nb-1] desired phases of the signals d input as long as Nb <Na, and uniquely, therefore by calculation without the need to use an optimization program, if Na = Nb.

b) We therefore know Nb distributions at the input of the distributor for example 63, and the Nb corresponding output distributions, given at the start. The determination of the transfer matrix of the output distributor 63 transforming Nb known complex input vectors with Na components into Nb known output vectors with Ne components is unique in the case where Nb = Na, i.e. if the number of amplifiers is equal to the number of beams. It is noted that this particular case is favorable since it makes it possible, for a semi-active system, to reduce the number Na of the amplifiers, it being understood that the number Ne of the radiating elements is generally greater, or even much greater than the number Nb of the beams . To determine this matrix, it suffices to write the Nb complex transfer equations for each of the Nb vectors, which provides NbxNb complex equations from which the determination of the NbxNb complex coefficients of the transfer matrix corresponding to the transfer function of the dispatcher is unique. This calculation is based on classical matrix algebra.

If you want to have more amplifiers that of beams (in the limit Na≤Ne), we can use the additional degrees of freedom to simplify the outlet distributor by introduction of up to (Na-Nb) (Nb-1) corresponding additional constraints in the optimization process.

The transfer function of the high dispatcher input excitation level and phases are so determined.

The synthesis of a microwave distributor 63 with known orthogonal transfer matrix can be implemented with architectures 103 with hybrid couplers and cascade phase shifters 102 (fig. 11 a ), or 103 ′ with distributors 102 ′ of the Blass type. (fig. 11 b ).

According to Figures 6 and 12, which illustrate the general case of a device according to the invention, the feeding device also includes a 65-phase shifter-distributor with Nb inputs (with Nb≤Na) and Na outputs, whose Na outputs are associated with Na inputs of the microwave distributor 63, if necessary by through converters, and whose Nb inputs correspond to the Nb beams required.

On transmission, this 65-phase shifter divides the signals applied to each of the Nb into Na beam entries and dephase appropriately each of the Na signals obtained for each beam by phase shifters 67. The signals from the different beams are, after phase shift, recombined on each of the Na outputs of the distributor-phase shifter 65 by a combiner 66. The combiner 66, which constitutes the device for forming beam at low level, and which remains of design classic, is the seat of losses associated with non-orthogonality bundles, which at this level do not affect performance (or - upon receipt - the noise) of the system.

The Nb dividers into Na signals of each of the bundles and Na combiners 66 can for example be of the "Wilkinson" type, if the distributor 65 operates in microwave. The device also includes Na modules amplifiers 64, nominally identical, which are inserted between the outputs of the 65-phase shifter-distributor, if required through converters frequency, and the Na inputs of distributor 63, if required via Na filters, not shown in Figure 6.

To the Na amplifiers can be added other modules to provide redundancy in the event of breakdown. On emission, these Na amplifiers amplify in powers the signals to be transmitted.

In reception mode, these Na amplifiers are identical, low noise, and amplify signals they receive from the distributor 63.

The device according to this embodiment of the invention thus presents, in combination, the elements radiant 61, lines 62, microwave distributor orthogonal 63 and the amplifier modules 64 operating all under nominal or quasi-nominal conditions, as well as the 65 phase-shifting distributor.

On transmission, the signals applied to each 65 low level dispatcher inputs are optimally subdivided and phase-shifted, fixed or reconfigurable, and amplified by amplifiers 64. They are then distributed by the high dispatcher level 63 with radiating elements 61 with amplitudes and the optimal phases to generate each of corresponding beams.

The power radiated by each beam can be controlled by switching more or less channels at the corresponding inputs of the low level dispatcher 65, which leads to the total reconfigurability of the traffic.

The cover reconfiguration is done either by activating the desired part of the Nb beams available, either by action on variable phase shifters 67, if any, or by a combination of the two.

The device of the invention works also at the reception and helps to limit noise received while ensuring for each beam the gain optimum. Amplifiers 64 are then replaced by low noise amplifiers, amplifying signals receipts from microwave 63.

A simplified configuration of the device (FIG. 7) of the invention, and of particular interest, is that obtained when Ne = Na = Nb = 2. The orthogonal microwave distributor 73 then reduces to the assembly of a fixed phase shifter 73 ₁ , producing a phase shift , and a directional coupler 73 ₂ characterized by its directivity ratio r with 0 ≤ r ≤ 1, the phase shifter 73 ₁ or section of line or guide being inserted between the directional coupler and one of the radiating elements 71 ₂ . On transmission, for any two prescribed beams, coherent signals of equal amplitudes and of optimized phases at the two input gates (power amplifiers), emerge with amplitudes and phase desired to produce these beams. On reception, for each beam, the non-equal signals received by radiating elements emerge equal in amplitudes to the amplifier outputs (at low noise). To calculate the phase shift  for the phase shifter and the ratio r for the coupler from the desired excitations for each of the two beams with radiating elements, it suffices for complex signals given (at reception) to write the two equations of equality "input" amplitudes, the term input Corresponding to the definition given above, one per beam. The unknowns  and r are deduced from these two equations. We go from reception to transmission by reciprocity.

This device is useful to facilitate the synthesis of two-beam systems (Nb = 2) with more than two elements, by successive equalization of the signals to several levels, from radiating elements 71 to amplifiers 74, the number of these remaining equal to the number of radiating elements 71.

Another configuration of the device (FIG. 8) of the invention of particular interest is that obtained when Ne = 4, Na = Nb = 2. The orthogonal microwave distributor 83, is then reduced to the assembly of six directional couplers (R ₁ .... R ₆ ), each characterized by its directivity ratio and each associated with a fixed phase shifter (D1 ... D6 ), each phase-shifter or section of line or guide being connected to one of the output ports of the corresponding directional coupler (R ₁ ..... R ₆ ). On transmission, for any two prescribed beams, coherent signals of equal amplitudes and of optimized phases at the two input gates (power amplifiers) emerge with amplitudes of phase desired to produce these beams. On reception, for each beam, the non-equal signals incident on the elements 81 ₁ to 81 ₄ emerge equal in amplitude "at the outputs" of the amplifiers 84 (at low noise).

The phase shifting modules comprising the three couplers R ₃ , R ₅ and R ₆ and their associated phase shifters D ₃ , D ₅ and D ₆ are calculated so as to concentrate, in reception mode, the power of the first beam towards a single gate "d ' input "of the modules, which does in this mode, output function. This calculation can be carried out in a known manner.

The two directional couplers R ₂ and R ₄ and the associated phase shifters D ₂ and D ₄ are calculated in reception mode so as to concentrate the available power of the second beam B ₂ towards a single "input" gate of each of the couplers D ₂ and D ₄ . Finally, the last (lower) coupler R ₁ and the associated phase shifter D ₁ are calculated in reception mode, to equalize for each beam (B ₁ , B ₂ ) the powers at the two "input" gates which in this mode operate output (using the same method as for the coupler and phase shifter of the previous device (fig. 7).

We go from reception to transmission by reciprocity.

This device is useful to facilitate the synthesis of two-beam systems (Nb = 2) with more than four elements (Ne≥4), by successive equalization of the signals at several levels, going from the radiating elements 81 ₁ to 81 ₄ towards the amplifiers 84 ₁ to 84 ₂ , the number of these being less than that of the radiating elements 81 ₁ to 81 ₄ .

A simplified configuration of the device of Figure 8 is shown in Figure 9, in which the elements corresponding to those of Figure 8 have the same reference number to which is added the sign "'". The directional coupler R ₁ and its associated phase shifter D ₁ have been eliminated. The device comprises five directional couplers (R ' ₂ ... R' ₆ ) and their five associated phase shifters (D ' ₂ ... D' ₆ ) which are interconnected like the directional couplers (R ₂ ... R ₆ ) and the phase shifters (D ₂ ... D ₆ ), except that an input of the couplers R ' ₂ and R' ₃ is connected to the output of an amplifier respectively 84 ' ₂ and 84' ₁ .

• On impose des amplitudes égales sur chaque entrée des coupleurs (R'₂...R'₆) pour les deux distributions d'entrée I1 et I2 correspondant aux deux distributions de sortie voulues 01 et 02.
• On peut sans perdre de généralité déphaser une des distributions de sorties voulues par exemple O2 pour rendre réel le produit scalaire P12 des distributions de sorties 01 et 02, avec P12 = cos(12).

The values of the ratios r of the directional couplers (R ' ₂ ... R' ₆ ) and of the phase shifts ) of the phase-shifting elements (D ' ₂ ... D' ₆ ) are determined according to the general method indicated below. above, namely:

• We impose equal amplitudes on each input of the couplers (R ' ₂ ... R' ₆ ) for the two input distributions I1 and I2 corresponding to the two desired output distributions 01 and 02.
• We can without losing generality phase shift one of the desired output distributions, for example O2 to make real the scalar product P12 of the output distributions 01 and 02, with P12 = cos (12).

• L'égalité du produit scalaire I1 par I2 avec le produit scalaire P12 de 01 par 02 conduit à des phases égales et opposées pour les deux composants de I2. Leur valeur est ± 12.
• On trouve alors facilement les distributions de sortie T1 et T2 correspondant respectivement à I1 = (1,0) correspondant à un signal présent sur l'entrée B1 seulement et I2 = (0,1) correspondant à un signal présent sur l'entrée B2 seulement T1 et T2 sont des combinaisons linéaires de 01 et 02.
• Ensuite on raisonne à la réception : Pour T1^* (T1 conjugué) incident sur les quatre éléments rayonnants 81'₁ à 81'₄, les modules R'₅ et R'₆ sont choisis tels que la puissance se concentre sur une seule de leurs entrées, ces deux entrées étant celles connectées au module R'₃ calculé de telle sorte que la puissance reçue soit concentrée sur sa porte connectée directement à un des modules de puissance 84'₁.
• Ensuite T2^* est incident et le module directif R'₄ est calculé pour que la puissance se concentre sur une seule de ses entrées, l'autre étant inutilisée. L'entrée utilisée du module R'₄ est connectée à la première sortie du module R'₂ qui, en mode réception, reçoit à son autre sortie la puissance venant du module directif R'₃. Le module R'₂ est calculé pour concentrer la puissance reçue vers une seule entrée, celle qui est connectée à l'autre module de puissance 84'₂. L'autre entrée du module R'₂ est inutilisée.

One can also choose the first real input distribution II, by adding to each input a phase shifter not shown.

• The equality of the dot product I1 by I2 with the dot product P12 of 01 by 02 leads to equal and opposite phases for the two components of I2. Their value is ± 12.
• We then easily find the output distributions T1 and T2 corresponding respectively to I1 = (1.0) corresponding to a signal present on the input B1 only and I2 = (0.1) corresponding to a signal present on the input B2 only T1 and T2 are linear combinations of 01 and 02.
• Then we reason at reception: For T1 ^* (T1 conjugate) incident on the four radiating elements 81 ' ₁ to 81' ₄ , the modules R ' ₅ and R' ₆ are chosen such that the power is concentrated on only one of their inputs, these two inputs being those connected to the module R ' ₃ calculated so that the power received is concentrated on its door directly connected to one of the power modules 84' ₁ .
• Then T2 ^* is incident and the directive module R ' ₄ is calculated so that the power is concentrated on only one of its inputs, the other being unused. The input used of the module R ' ₄ is connected to the first output of the module R' ₂ which, in reception mode, receives at its other output the power coming from the directive module R ' ₃ . The module R ' ₂ is calculated to concentrate the power received towards a single input, that which is connected to the other power module 84' ₂ . The other input of module R ' ₂ is unused.

The device of figure 10 illustrates the case a network antenna (here at eight sources) producing two bundles B1 and B2 from one of two sources, and the other of the eight sources. These beams of widths are clearly non-orthogonal (around the axis, the power incident on the antenna cannot clearly not be fully captured by the B2 beam, without a part going to beam B1 - hence a loss compared to the case of a single beam).

A known way to avoid the impact of this loss is to associate an amplifier module with each of the eight radiating elements. (This results in eight modules and a 2x8 splitter).

With the device of the invention, the loss of non-orthogonality is also eliminated, but there is no longer only two amplifier modules and a distributor similar.

The device of FIG. 10 presents more particularly a simplified configuration of the device of the invention when Ne = 8, Na = Nb = 2. The beam B1 emanates from the two radiating elements 91 ₇ and 91 ₈ and the beam B2 from all the eight radiating elements 91 ₁ and 91 ₈ . The orthogonal microwave distributor 93 is then reduced to the assembly of nine directional couplers R ₁₁ to R ₁₉ each characterized by its directivity ratio r and each associated with a fixed phase shifter D ₁₁ to D ₁₉ , each phase shifter or line section or guide being connected to one of the doors of the corresponding coupler. On transmission, for any two prescribed beams, coherent signals, of equal amplitudes and of optimized phases, present at the two input gates of the power amplifiers 94, emerge with amplitudes and phases desired to produce these beams B1 and B2. On reception, for each beam, the non-equal signals incident on the elements 91 ₁ to 91 ₈ emerge equal in amplitude to the "inputs" of the amplifiers 94.

The seven couplers R ₁₃ to R ₁₉ and the associated phase shifters D ₁₃ to D ₁₉ of FIG. 9 are calculated so as to concentrate the power of the beam B2 towards a single input port of the couplers R ₁₃ to R ₁₉ . The coupler R ₁₂ and phase shifter D ₁₂ associated in dashes concentrate the power of B1 on a single input port of the coupler R ₁₂ . The input coupler R ₁₁ equalizes the powers for B1 and B2 at each of its "inputs" to the amplifiers (using the same method as for the coupler and the phase shifter in FIG. 7). The calculations are made on reception, the "inputs" of the couplers making, in this case, an output function according to the definition given above.

We go from reception to transmission by reciprocity.

According to the embodiment of FIG. 13 (Nb = 2, Ne = Na = 4), the power distributor comprises four directional modules (R " ₃ , D" ₃ ), (R " ₃ , D" ₄ ), ( R " ₅ , D" ₅ ) and (R " ₆ , D" ₆ ), which are interconnected like the directional modules (R ' ₃ , D' ₃ ) ... (R ' ₆ , D' ₆ ) of the figure 9.

The determination of policy reports and phase shifts are carried out as follows:

The directional modules (R " ₅ , D" ₅ ) and (R " ₆ , D" ₆ ) are calculated, in reception mode, so as to equalize the amplitudes of the signals on each of their inputs, this for each distribution (beam) incident on elements 111 ₁ to 111 ₄ . Similarly, the two directional modules (R " ₃ , D" ₃ ) and (R " ₄ , D" ₄ ) are calculated so as to equalize the amplitudes on each of their inputs, this for each incident distribution (beam). On transmission, the distributions and consequently the desired beams are obtained by reciprocity from uniform amplitude distributions at the inputs of the amplifiers 114 ₁ to 114 ₄ .

Figure 20 shows an architecture favorite of the power distributor 63. Its advantage is to be symmetrical and not to present a crossover, such as for example those between elements R3 to R6, or R'3 to R'6 or R "3 to R" 6 in Figures 8, 9 and 13. It can be used in place of cascade distributors Figures 3a, 3b, 8, 9, 11a and 13 or even Blass matrices of Figures 1a, 1b, 2c, 2b and 11b. This architecture can also be used for many other applications: this power is in itself a power divider lossless microwave.

The architecture represented corresponds to the cases where Na = Ne = 8.

The splitter has eight E1 input ports to E8 (Na = 8) and eight output ports corresponding to eight antennas 61 (Ne = 8).

The 8 x 8 dispatcher transfer matrix is first determined using the rules of design described above, from Nb optimal distributions or "output vectors" corresponding to the aforementioned Nb beams.

The term "complex distribution" means below the complex conjugate of a line in the matrix of complex transfer.

• une rangée centrale de coupleurs hybrides à deux entrées et deux sorties référencés C1 à C3 en allant de la sortie (antennes 61) vers l'entrée. Chaque coupleur hybride présente à chacune de ses sorties un déphaseur, respectivement CDL1 et CDR1 pour C1, CDL2 et CDR2 pour C2 et CDL3 et CDR3 pour C3 ;
• un groupe de "gauche" de coupleurs hybrides à deux entrées et deux sorties référencés LL1 à LL12 en allant de la sortie vers l'entrée et qui présentent à une de leurs sorties un déphaseur respectivement LD1 à LD12, ce déphaseur étant disposé dans la sortie sg disposée à gauche sur le dessin pour les coupleurs LL4 à LL12 et dans la sortie sd à droite sur le dessin pour les coupleurs LL1 à LL3, dont les sorties droites sd attaquent les antennes correspondantes 61₂ à 61₄, par l'intermédiaire d'un dit déphaseur (respectivement LD1, LD2, LD3), la sortie gauche du coupleur LL1 attaquant directement l'élément d'antenne 61₁ situé le plus à gauche ;
• un groupe de "droite" de coupleurs hybrides à deux entrées et deux sorties référencés RR1 à RR12 en allant de la sortie vers l'entrée et qui présentent à une de leurs sorties un déphaseur respectivement RD1 à RD12, ce déphaseur étant disposé dans la sortie sd disposée à droite sur le dessin pour les coupleurs RR4 à RR12 et dans la sortie sg à gauche sur le dessin pour les coupleurs RR1 à RR3 dont la sortie gauche attaque les antennes correspondantes 61₅ à 61₇ par l'intermédiaire d'un dit déphaseur (respectivement RD1, RD2, RD3), la sortie droite du coupleur RR1 attaquant directement l'élément d'antenne 61₈ situé le plus à droite..

The matrix includes hybrid complexes associated with phase shifters. The assembly is symmetrical and includes:

• a central row of hybrid couplers with two inputs and two outputs referenced C1 to C3 going from the output (antennas 61) to the input. Each hybrid coupler has at each of its outputs a phase shifter, respectively CDL1 and CDR1 for C1, CDL2 and CDR2 for C2 and CDL3 and CDR3 for C3;
• a group of "left" hybrid couplers with two inputs and two outputs referenced LL1 to LL12 going from the output to the input and which present at one of their outputs a phase shifter respectively LD1 to LD12, this phase shifter being disposed in the output sg arranged on the left in the drawing for couplers LL4 to LL12 and in the output sd on the right in the drawing for couplers LL1 to LL3, whose straight outputs sd attack the corresponding antennas 61 ₂ to 61 ₄ , via d 'a said phase shifter (respectively LD1, LD2, LD3), the left output of the coupler LL1 directly attacking the antenna element 61 ₁ located furthest to the left;
• a group of "straight" hybrid couplers with two inputs and two outputs referenced RR1 to RR12 going from the output to the input and which present at one of their outputs a phase shifter respectively RD1 to RD12, this phase shifter being disposed in the output sd arranged on the right in the drawing for couplers RR4 to RR12 and in the output sg on the left in the drawing for couplers RR1 to RR3 whose left output attacks the corresponding antennas 61 ₅ to 61 ₇ by means of a said phase shifter (RD1, RD2, RD3 respectively), the right output of the RR1 coupler directly attacking the antenna element 61 ₈ located furthest to the right.

• une première ligne composée de l'aval vers l'amont des coupleurs LL1, LL4, LL7, LL9, LL11 et LL12 ;
• une deuxième ligne composée des coupleurs LL2, LL5, LL8 et LL10 ;
• une troisième ligne composée des coupleurs LL3 et LL6 ;
• une ligne centrale composée des coupleurs C1, C2 et C3 ;
• une cinquième ligne composée des coupleurs RR3 et RR6 ;
• une sixième ligne composée des coupleurs RR2, RR5, RR8 et RR10 ;
• une septième ligne composée des coupleurs RR1, RR4, RR7, RR9, RR11 et RR12.

Hybrid couplers are connected along seven lines of cascaded couplers, namely:

• a first line composed of downstream to upstream of the couplers LL1, LL4, LL7, LL9, LL11 and LL12;
• a second line composed of couplers LL2, LL5, LL8 and LL10;
• a third line composed of couplers LL3 and LL6;
• a central line composed of couplers C1, C2 and C3;
• a fifth line composed of the couplers RR3 and RR6;
• a sixth line composed of the couplers RR2, RR5, RR8 and RR10;
• a seventh line composed of the couplers RR1, RR4, RR7, RR9, RR11 and RR12.

• sortie de la branche de droite de LL12, puis entrée et sortie de la branche de gauche de C3, de la branche de droite de LL11, de la branche de gauche de LL10, de la branche de droite de LL9, de la branche de gauche de LL8 et ainsi de suite pour LL7, LL5, LL4, LL2 et LL1 avec interposition des déphaseurs CDL3, LD10, LD8 et LD5, la sortie droite de LL1 attaquant l'élément d'antenne 62₂ à travers le diphaseur LD1..

At the interfaces between the lines, the couplers are connected in cascade alternately with those of the adjacent line (except for couplers C1 to C3), namely:

• leaving the right branch of LL12, then entering and leaving the left branch of C3, the right branch of LL11, the left branch of LL10, the right branch of LL9, the left branch of LL8 and so on for LL7, LL5, LL4, LL2 and LL1 with interposition of phase shifters CDL3, LD10, LD8 and LD5, the right output of LL1 attacking the antenna element 62 ₂ through the diphaser LD1 ..

To determine the hybrid couplers and the phase shifters, we operate in reception mode: we assume that signals of complex distributions are received on the eight antenna elements and that the splitter directs each of them to the port of entry corresponding.

The example below corresponds to the case Nb = Na.

The hybrid couples LL1, LL2 and LL3 as well as the phase shifters LD1, LD2 and LD3 are chosen so as to direct the signals coming from the first distribution and available on the antenna elements 61 ₁ to 61 ₄ towards the right input ed of the LL3 coupler.

The same operation is performed symmetrically at the level of the hybrid couplers RR1, RR2 and RR3 and their phase shifter RD1, RD2 and RD3, for the signals of a second distribution orthogonal to the first which are received on the other antenna elements. further to the right 61 ₅ to 61 ₈ . These signals of the second distribution are thus routed to the left input eg of RR3. The following two couplers LL4 and LL5 and the corresponding phase shifters LD4 and LD5 are determined to direct the signals of the second distribution received on the antenna elements 61 ₁ to 61 ₄ to the right input ed of the coupler LL5 (the term "input "being defined in a configuration in transmission mode).

The two couplers RR4 and RR5 and their associated phase shifters RD4 and RD5 are determined to direct the signals of the first distribution received on the antenna elements 61 ₅ to 61 ₈ to the left input eg of the coupler RR5.

The coupler C1 and the associated phase shifters CDL1 and CDR1 whose outputs attack the inputs respectively right and left of LL3 and RR3, are determined to direct the signals from the first distribution which are present at the right ed entrance of LL3 to the right input port of coupler C1.

The signals of distribution 1 and 2 are therefore spread over four ports of entry, namely the port right ed of the coupler LL5, which in reception mode only receives signals only from the second distribution, the port left eg of the RR5 coupler which in reception mode does not receive of signals that from the first distribution, the port left input eg of coupler C1, which receives signals from the second distribution but receives no signal of the first distribution, since this is directed only to the right port ed of coupler C1, and finally the right input port ed of coupler C1, which receives first distribution signals but on which it does may be hypothesized to signal the second distribution, otherwise the dot product of these two distributions would be nonzero which would be contrary to the orthogonality criterion that has been set.

The LL6 coupler and its associated phase shifter LD6 are configured to direct the signals of the second distribution which are present at the port eg of C1 and to the ed port of LL5 to its right entry port ed, which constitutes the input E2, and the coupler RR6 and its DD6 associated phase shifter are configured to direct the first distribution signals, which are present on the port ed of C1 and on the port eg of RR5, on the left input port eg of RR6 which constitutes the input E1.

Note that all of the couplers C1, LL1 to LL6, RR1 to RR6, and their associated phase shifters constitute an orthogonal and symmetrical hybrid coupler with two inputs (E1, E2) and eight outputs (Na = 2 and Ne = 8).

Selection of couplers and phase shifters associated can be performed by bundles 3 and 4, 5 and 6, and finally 7 and 8 using the same procedure, to bring to a coupler 8 x 8 8 (Nb = Na = Ne = = 8). The same procedure is suitable for any even number of entry and exit.

Another simplified configuration of the device of the invention can be obtained by relaxing the constraint of strict equality of the signals of each beam to each amplifier module, tolerating a weak "ripple" of for example ± 1 dB. Optimization components of the distributor is then done by a conventional optimization procedure by imposing a maximum "ripple" at module level amplifiers.

All or part of the phase shifters used in the context of the present invention can also be variables to reconfigure all or part of the beams, for example if a satellite changes its coverage. The power distributor must then be sized to the set of achievable beams, which are not all activated at the same time. The phase shifters can be analog or quantized (digital).

The distributor-phase shifter 65 can operate in microwave at transmission (or reception) frequency. Amplification can be performed if necessary level of the inputs of the phase-shifter 5.

The distributor-phase shifter 65 can also operate at an intermediate frequency; a converter frequency is then connected to each of its Na outputs.

The distributor-phase shifter 65 can also be of digital type. It is then followed by converters digital / analog and possibly converters frequency.

The radiating sources 101 can be direct radiation and arranged on a surface by flat example (referenced 1 in fig. 12), cylindrical, conical, spherical, or on another surface.

The device of the invention can be combined either to a reflector 1 '(fig. 6) or to a lens. The device can be combined with a system multi-reflectors or multi-lenses or a mixture of reflectors and lenses.

The device according to the invention can be associated either with a reflector or with a lens conformed to improve performance. The device according to the invention can in particular be associated either with a reflector or with a lens oversized.

In the event that the device according to the invention associated either with a reflector or with a lens, the surface on which the sources are located can be optimized or moved around the fireplace.

As is apparent from the description above, the essential advantage of the device is that it is able to generate exactly non-orthogonal distributions of amplitudes and phases on the radiating elements, and therefore to overcome the associated directivity losses. the constraints of conventional multimode distributors and multimator systems. All the amplifiers 64 can operate at (or in the vicinity of) their nominal level, which produces the best power output for the transmission whatever the conditions of allocation of channels to the beams.

In the case where the number of Na amplifiers common to the beams is equal to the number of beams to be produced Nb, the complexity of the device's output distributor is exactly the same as for a conventional multimode (passive) distributor designed to generate the same beams with a beam amplifier module (fig. 3, 11 a and 11 b ).

This is because the matrices orthogonal, although very different in their functions and in the values of their components, have the same number of entry doors Na and exit Ne, and by then the same number of couplers (Ne-1 + Ne-2 + ... + Ne-Na).

So there is for the same complexity and the same technology the advantage of superior directivity for each beam.

The flexibility to allocate power to beams with optimal amplifier performance at the emission is an intrinsic quality of the device.

The output distributor being lossless, the activated beams can be reconfigured by readjustment of the corresponding phases at the input of amplifiers.

In its configuration operating on reception, the device retains the advantage of increased directivity compared to conventional multimode (passive ) distributors.

Compared to an active or semi-active antenna classic, it reduces the number low noise amplifiers from Ne to Nb (number of bundles) which can be much lower.

les quatre faisceaux sont :

1) Pan-Européen (fig. 14)

2) GB/Europe (Gain min GB = Gain min Europe + 3dB) (fig. 15)

3) Italie/Europe (Gain min Italie = Gain min Europe + 3dB) (fig. 16)

4) Espagne/Europe (Gain min Espagne = Gain min Europe + 3dB) (fig. 17).

Les trois systèmes d'alimentation :

• Répartiteur multimodes (1 amplificateur par canal/faisceau)
• Répartiteur multimatrices (3 matrices 8x8, 24 amplificateurs, à phases optimisées)
• Répartiteur semi-actif orthogonal (4 amplificateurs)

ont été calculés en mettant en oeuvre le procédé décrit ci-dessus et les gains obtenus sont consignés dans le tableau ci-dessous. Couverture Multimodes (Art antérieur) Multimatrices (Art antérieur) Dispositif selon l'invention Gmin pays/Gmin EU Gmin pays/Gmin EU Gmin pays/Gmin EU Pan-EU - /31.25 dB - /31.05 dB - /31.67 dB GB-EU 33,10 dB/30,10 dB 33,55 dB/30,55 dB 34,12 dB/31,12 dB IT-EU 32,66 dB/29,66 dB 33,15 dB/30,15 dB 33,82 dB/30,82 dB ES-EU 33,28 dB/30,28 dB 33,02 dB/30,02 dB 33,77 dB/30,77 dB

The device of the invention was evaluated for the generation of four beams (Nb = 4) from a geostationary satellite antenna:

the four beams are:

1) Pan-European (fig. 14)

2) GB / Europe (Gain min GB = Gain min Europe + 3dB) (fig. 15)

3) Italy / Europe (Gain min Italy = Gain min Europe + 3dB) (fig. 16)

4) Spain / Europe (Gain min Espagne = Gain min Europe + 3dB) (fig. 17).

The three feeding systems:

• Multimode splitter (1 amplifier per channel / beam)
• Multimaterial splitter (3 8x8 matrices, 24 amplifiers, with optimized phases)
• Semi-active orthogonal splitter (4 amplifiers)

have been calculated by implementing the method described above and the gains obtained are recorded in the table below. Blanket Multimodes (Prior art) Multimatrices (Prior art) Device according to the invention Gmin country / Gmin EU Gmin country / Gmin EU Gmin country / Gmin EU Pan-EU - /31.25 dB - /31.05 dB - /31.67 dB GB-EU 33.10 dB / 30.10 dB 33.55 dB / 30.55 dB 34.12 dB / 31.12 dB IT-EU 32.66 dB / 29.66 dB 33.15 dB / 30.15 dB 33.82 dB / 30.82 dB ES-EU 33.28 dB / 30.28 dB 33.02 dB / 30.02 dB 33.77 dB / 30.77 dB

Compared to the multimode complexity system comparable, the device of the invention provides a gain improvement from 0.42 to 1.16 dB depending on the bundles.

Compared to the 24-hour multimeter system amplifiers, the device according to the invention provides an improvement in directivity from 0.62 to 0.75 dB depending on the beams.

• Aux antennes d'émission, d'émission-réception ou de réception à faisceaux formés multiples pour satellites de communications avec reconfiguration du trafic et de la couverture.
• Aux antennes de télémesure et de télécommande.
• Aux antennes de radars à multi-couvertures.
• Aux antennes pour faisceaux hertziens à diversité angulaire.
• Aux antennes de stations relais pour téléphonie avec mobiles.

The device of the invention can possibly be applied:

• At transmitting, transmitting-receiving or receiving antennas with multiple beams for communications satellites with reconfiguration of traffic and coverage.
• To telemetry and remote control antennas.
• Multi-cover radar antennas.
• Antennas for radio-relay systems with angular diversity.
• At the antennas of relay stations for telephony with mobiles.

Claims (28)

1. A feed device for a multisource semiactive antenna with multiple beams, of the type successively including:

   a) a low-level beam shaper device (65) splitting Nb beam input signals as a function of desired coverage characteristics and combining them, after phase shifting, to form Na output signals on its Na outputs, said beam shaper device having a nonorthogonal transfer matrix,

   b) Na amplifier modules (64), amplifying, in transmission mode, the Na output signals,

   c) an output power splitter (63), arranged between the Na amplifier modules (64) and Ne radiating elements (61), and having an orthogonal transfer matrix

      wherein Nb ≤ Na s Ne, and wherein the orthogonal transfer function of the power splitter (63) is such that it permits change between, on the one hand, Nb distributions at the input of the power splitter (63), in which the amplitude of the Na signals is substantially equal for each of the Nb beams, and in which the phase of the Na signals satisfied at least the condition of equality of the scalar products, taken in pairs, of the Nb excitation vectors at the input of the power splitter (63), and of the scalar products, taken in pairs, of the Nb corresponding output excitation vectors and, on the other hand, Nb predetermined output distributions.
2. The device as claimed in claim 1, wherein, at the input of the power splitter, the phases of the signals corresponding to one of said Nb distributions is zero.
3. The device as claimed in one of claims 1 or 2, wherein the power splitter includes at least one directional module comprising a directional coupler with two inputs and two outputs and having a given directionality ratio r, and at least one associated phase-shifter element coupled to one output of the directional coupler, the output of said phase shifter constituting a first output of the directional coupler.
4. The device as claimed in claim 3, wherein the power splitter includes [(Ne - 1) + (Ne - 2) + ... + (Ne - Na)] directional modules.
5. The device as claimed in one of claims 1 to 4, wherein Nb = Na.
6. The device as claimed in claim 5, wherein Nb = Na = Ne = 2, and wherein the power splitter (63) includes a single directional module (73₁, 73₂), comprising one said directional coupler (73₂), having a given directionality ratio r, the inputs of which are coupled to the outputs of the amplifier modules (74), and a phase-shifter element (73₁) arranged between one output of the directional coupler (73₂) and one of the two radiating elements (71), the other output of the directional coupler (73₂) being directly connected to the other radiating element.
7. The device as claimed in claim 5, wherein Nb = Na = 2, and wherein Ne ≥ 4, and wherein the directional splitter includes at least five directional modules, each of which includes a directional coupler, having a given directionality ratio r, the inputs of which constitute the inputs of the directional module and which has at a first output a phase-shifter element which is associated with it, the first output of the directional module consisting of the output of the associated phase-shifter element.
8. The device as claimed in claim 7, which includes five directional modules, namely a first directional module (R'₂, D'₂) having one input connected to the output of a first amplifier module (84'₂) and having its first and second outputs connected to one input, respectively, of a second (R'₄, D'₄) and of a third (R'₃, D'₃) directional module, the third directional module (R'₃, D'₃) also having a second input connected to the output of a second amplifier module (84'₁), the first and second outputs of the second directional module (R'₄, D'₄) being connected to a first input, respectively, of a fourth directional module (R'₆, D'₆) and of a fifth directional module (R'₅, D'₅), the first and second outputs of the third directional module (R'₃, D'₃) being connected to a second input, respectively, of the fifth (R'₅, D'₅) and of the fourth (R'₆, D'₆) directional module, and the outputs of the fourth (R'₆, D'₆) and fifth (R'₅, D'₅) directional modules each being connected to one radiating element (81'₁, 81'₂, 81'₃, 81'₄).
9. The device as claimed in claim 8, wherein the directionality ratio r of the first directional coupler (R'₁) of the first directional module (R'₂, D'₂) and the phase shift of the phase-shifter element (D'₂) which is associated with it are such that, in reception mode, the power at the two input ports of the first directional module (R'₂, D'₂) is the same for each of the two beams (B₁, B₂), and wherein the directionality ratio r of the directional couplers (R'₅, R'₆) of the fourth (R'₆, D'₆) and fifth (R'₅, D'₅) directional modules, and the phase shifts of their associated phase-shifter elements (D'₅, D'₆) are such that the power corresponding to the first beam (B₁) is concentrated in the reception mode toward a single one of their input ports, and wherein the ratio r of the phase-shifter element (R'₃) of the third directional module (R'₃, D'₃) and the phase shift of the associated phase-shifter element (D'₃) are such that the power corresponding to the first beam (B₁) is concentrated toward its second input, and wherein the directionality ratio r of the directional coupler (R'₂, R'₄) of the first (R'₂, D'₂) and second (R'₄, D'₄) directional modules and the phase shifts of their associated phase-shifter elements (D'₂, D'₄) are such that the output power of the second beam (B₂) is concentrated, in the reception mode, toward a single one of their input ports.
10. The device as claimed in claim 5, wherein Nb = Na = 2, and wherein Ne = 8, and wherein the directional splitter includes nine directional modules, each of which has a directional coupler, having a given directionality ratio r, the inputs of which constitute the inputs of the directional module, and having at a first output a phase-shifter element which is associated with it, the output of the associated phase-shifter element constituting the first output of the directional module, a first (R₁₆, D₁₆), second (R₁₇, D₁₇), third (R₁₈, D₁₈) and fourth (R₁₉, D₁₉) output directional module, having their outputs each connected to one radiating element (91₁,...,91₈), an input directional module (R₁₁, D₁₁) having its inputs connected to the outputs of amplifier modules (94), and a first (R₁₂, D₁₂), second (R₁₃, D₁₃), third (R₁₄, D₁₄) and fourth (R₁₅, D₁₅) intermediate directional module, which are arranged in cascade, the first intermediate directional module (R₁₂, D₁₂) having one input coupled to the second output of the input directional module (R₁₁, D₁₁), its first and its second outputs being coupled respectively to one input of the fourth output directional module (R₁₉, D₁₉) and to one input of the second intermediate directional module (R₁₃, D₁₃), the second intermediate module (R₁₃, D₁₃) having one input coupled to the first output of the input directional module (R₁₁, D₁₁) and having its first and its second outputs coupled respectively to one input of the fourth output directional module (R₁₉, D₁₉) and to one input of the third intermediate directional module (R₁₄, D₁₄), the third intermediate directional module (R₁₄, D₁₄) having its first and second outputs coupled respectively to one input of the fourth intermediate directional module (R₁₅, D₁₅) and to one input of the third output directional module (R₁₈, D₁₈) , and the fourth intermediate directional module (R₁₅, D₁₅) having its first and second outputs coupled respectively to one input of the second (R₁₅, D₁₅) and of the first (R₁₆, D₁₆) output directional modules.
11. The device as claimed in claim 10, wherein the ratios r of the output couplers and of the second (R₁₃, D₁₃), third (R₁₄, D₁₄) and fourth (R₁₅, D₁₅) intermediate directional modules, as well as the phase shifts of the phase-shifter elements which are associated with them, are chosen so as to concentrate, in the reception mode, the power corresponding to a directional beam toward a single one of their input ports, while the ratio r of the directional coupler of the first intermediate directional module (R₁₂, D₁₂), and the phase shift of the phase-shifter element which is associated with it, are such that they concentrate, in the reception mode, the power of a nondirectional beam toward a single one of their input ports, and wherein the ratio r of the directional coupler of the input phase-shifter module (R₁₁, D₁₁), and the phase shift of the phase-shifter element which is associated with it, are such that the powers are the same for the two beams at the inputs of the input phase-shifter module (R₁₁, D₁₁), and therefore on the outputs of the two amplifier modules (94).
12. The device as claimed in claim 3, wherein Nb = 2, Na = 4 and Ne = 4, and which includes a first (R"₃, D"₃) and a second (R"₄, D"₄) upstream directional module, the inputs of which are each connected to one output of an amplifier module (114₁, 114₂, 114₃, 114₄), as well as a first (R"₅, D"₅) and a second (R"₆, D"₆) downstream directional module, the outputs of which are connected to the radiating elements (111₁, 111₂, 111₃, 111₄), and wherein the first and the second outputs of the first upstream directional module (R"₃, D"₃) are connected respectively to one input of the first (R"₅, D"₅) and of the second (R"₆, D"₆) downstream directional modules, and wherein the first and the second outputs of the second upstream directional module (R"₄, D"₄) are connected respectively to one input of the second (R"₆, D"₆) and of the first (R"₅, D"₅) downstream directional modules.
13. The device as claimed in claim 12, wherein the ratio r and phase shift of the first (R"₅, D"₅) and of the second (R"₆, D"₆) downstream directional modules are such that, in reception mode, the amplitudes of the signals on each of their inputs are equal, for each of the two incident beams (B₁, B₂), and wherein the ratio r and the phase shift of the first (R"₃, D"₃) and of the second (R"₄, D"₄) upstream directional modules are such that, in reception mode, the amplitudes of the signals on their inputs are equal, for each of the two incident beams (B₁, B₂) .
14. The device as claimed in one of claims 1 to 7, wherein the output power splitter (63) includes a plurality of phase-shifter modules, including at least one input module, the inputs of which are connected to the outputs of the amplifier modules (64), and wherein the directionality of the input module or modules is such that, for each beam, the powers on each of the inputs of the input phase-shifter module or modules are the same, and wherein the other phase-shifter module or modules do not respect this condition.
15. The device as claimed in one of claims 3 to 5, wherein the power splitter (63) includes a plurality of directional modules which include a directional coupler (LL1...LL12; RR1...RR12; C1...C3) having two inputs and two outputs and having, in the case of a directional module of a first type (LL1...LL12; RR1...RR12), one phase-shifter element (LD1...LD12; RD1...RD12) arranged at a single one of the two outputs of said directional coupler (LL1...LL12; RR1...RR12), the output of the phase-shifter constituting the output of the module, and, in the case of a directional module of a second type (C1...C3; CDL1...CDL3; CDR1...CDR3), one phase-shifter element (CDL1...CDL3; CDR1...CDR3) arranged at each of the two outputs of the directional coupler (C1...C3), the outputs of the phase shifters constituting the outputs of the module; and which includes a symmetrical cascade arrangement without crossover, comprising a central line which includes at least one directional module (C1...C3; CDL1...CDL3; CDR1...CDR3) of the second type, this central line being symmetrically surrounded by at least one left line (LL1...LL12; LD1...LD12) and by at least one right line (RR1...RR12; RD1...RD12) of directional modules of the first type, which are arranged in cascade without crossover, at least two directional modules (LL6, LD6, RR6, RD6) of the first type constituting input modules having at least one input constituting the Na inputs (E1, E2...E8) of the power splitter, and which has directional modules of the first type constituting output modules (LL1, LL2, LL3, RR1, RR2, RR3) and having at least one output connected to one input of the Ne antenna elements (61₁...61₈) .
16. The device as claimed in claim 15, wherein the directional modules of the first type which are arranged on one single side, respectively left (LL1...LL12; LD1...LD12) or right (RR1...RR12; RD1...RD12) relative to said central line, have their phase-shifter element (LD1...LD12; RD1...RD12) arranged in the left or right output, respectively, of their directional coupler (LL1...LL12; RR1...RR12).
17. The device as claimed in claim 16, wherein the directional modules of the first type (LL4...LL11; LD4...LD11) which are neither input modules nor output modules, and which are situated on the left side relative to said central line have at least their right input (ed) connected to the left output (sg) of an upstream directional module, and vice versa symmetrically for said modules (RR4...RR11; RD4...RD11) situated on the right side.
18. The device as claimed in claim 17, wherein the directional modules of the first type (LL4, LL7, LL9, LL11; LD4, LD7, LD9, LD11) which are neither input modules nor output modules, and which are situated on an extreme left line relative to said central line, have their left input (eg) connected to the left output (sg) of an upstream directional module, and their right input (ed) connected to the left output (sg) of another upstream directional module, and vice versa symmetrically for said modules (RR4, RR7, RR9, RR11, RD4, RD7, RD9, RD11) situated on the right side.
19. The device as claimed in one of claims 3 to 18, wherein at least one phase-shifter element is variable, so as to allow at least partial reconfiguration of the beams.
20. The device as claimed in one of the preceding claims, wherein the beam shaper device (65) operates at a frequency which is intermediate relative to the transmission/reception frequency of the device, and which includes a frequency converter at each of its Na outputs.
21. The device as claimed in one of the preceding claims, wherein the beam shaper device (65) operates at the transmission/reception frequency of the device.
22. The device as claimed in one of the preceding claims, wherein the beam shaper device (65) is digital and includes digital/analog converters at output.
23. The device as claimed in one of the preceding claims, wherein said equality between the amplitudes of the Na signals for each of the Nb beams is produced by tolerating a slight ripple, of the order of ± 1dB, between the Na signals.
24. An antenna which includes a focusing device comprising at least one reflector and/or at least one lens, and a feed device as claimed in one of the preceding claims, the Ne radiating elements which are associated with it being positioned relative to the focusing device so as to obtain focusing on transmission and/or on reception.
25. A method for determining the transfer function of the output power splitter of a feed device for a multisource semiactive antenna with multiple beams, of the type successively including:

    a) a low-level beam shaper device splitting Nb beam input signals as a function of desired coverage characteristics and combining them, to form Na output signals on its Na outputs, said beam shaper device having a nonorthogonal transfer matrix,

    b) Na amplifier modules, amplifying, in transmission mode, the Na output signals,

    c) said output power splitter, which is arranged between the Na amplifier modules and Ne radiating elements, and having an orthogonal transfer matrix, which includes the following steps, with Nb s Na ≤ Ne:

    setting the Na amplitudes of the distributions at the input of said power splitter to be equal for each of the Nb beams,

    deducing therefrom Nb(Nb-1) equalities of the complex scalar products, taken in pairs, of the Nb complex excitation vectors at the input of the splitter and of the Nb output excitation vectors,

    determining, directly or by an optimization program, the phases of the input signals,

    deducing therefrom the transfer function of the splitter.
26. The method as claimed in claim 25, wherein, at the input of the power splitter, the phases of the signals corresponding to one of said Nb distributions are zero.
27. The method as claimed in one of claims 25 or 26, wherein the power splitter includes at least one directional module comprising a directional coupler with two inputs and having a given directionality ratio r, and one associated phase-shifter element coupled to one output of the directional coupler.
28. The method as claimed in claim 27, wherein the power splitter includes [(Ne - 1) + (Ne - 2) + ... + (Ne - Na)] directional modules.

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