ITRM20090300A1 - SLOT SLIP ANTENNA WITH POWER SUPPLY IN WAVE GUIDE AND PROCEDURE FOR REALIZING THE AERIAL OF THE SAME - Google Patents

Description

Array slot antenna with waveguide power supply and antenna construction procedure

DESCRIPTION

The present invention relates to the technical sector of antennas for telecommunication systems and in particular it refers to a slot array antenna with waveguide power supply and to a process for its realization.

Waveguide powered slot array antennas are currently widely used in navigation systems, radar systems and other telecommunications applications, such as aeronautics and missile applications. Such antennas generally comprise one or more radiant waveguides having a plurality of radiant slots, designed to radiate electromagnetic radiation, and each having at least one coupling slot designed to operatively couple the radiant waveguide to a waveguide. Power wave, so as to be able to feed the radiant wave guide, therefore the radiant slots, with electromagnetic radiation. Obviously, in radar systems, the same antenna is used for both transmission and reception, so in reception, exploiting the reciprocity of the antenna, the radiant slots are used to receive electromagnetic radiation reflected by a target.

Waveguide powered slot array antennas for aeronautical, radar and missile applications are generally currently made using radiant waveguides having an aluminum structure, in which the radiant slots and coupling slots are openings passers made respectively in the upper and lower walls of the guide and obtained by electro-erosion techniques or by laser or mechanical processing.

Also belonging to the state of the art is a method of manufacturing slot array antennas with waveguide power supply according to which the array of radiant slots is provided on a copper sheet, creating through openings on this sheet using photoengraving techniques. The radiant waveguides are made as blocks of copper or aluminum with essentially "U" section which are made integral with the sheet by means of relatively expensive and complicated techniques, such as dip brazing.

These manufacturing techniques described above allow to obtain processes capable of satisfying the accuracy generally required by the applications, but have the drawback of requiring relatively high manufacturing costs.

The purpose of the present invention is to make available a slot array antenna with waveguide power supply that can be manufactured by means of a process capable of guaranteeing the required precision at relatively low costs compared to the costs of the above manufacturing techniques. described with reference to the antennas of the prior art.

This object is achieved by means of a slot array antenna as defined in general in the attached claim 1.

Advantageous embodiments of a slot array antenna according to the present invention are defined in the attached dependent claims.

The present invention also relates to a process for manufacturing a slot array antenna with waveguide power supply as defined in claim 8 in its general form and in the subsequent claims in particular embodiments.

Further characteristics and advantages of the invention will appear from the detailed description that follows, carried out purely by way of non-limiting example, with reference to the attached drawings, in which:

Figure 1 is a schematic side view of a first embodiment of a multilayer slot array antenna with waveguide power supply;

- figure 2 is a plan view showing a first layer of the antenna of figure 1;

- figure 3 is a plan view showing a second layer of the antenna of figure 1;

- figure 4 is a plan view showing a third layer of the antenna of figure 1;

- figure 5 is a plan view showing a part of figure 2 in greater detail;

- figure 6 is a side sectional view of a portion of the antenna of figure 1;

- figure 7 is an exemplary block diagram of a process for manufacturing a slot array antenna with waveguide power supply;

- Figure 8 shows a side sectional view of a slot array antenna according to a first embodiment variant; And

- Figure 9 schematically shows a part of a slot array antenna according to a second embodiment variant.

With reference to the attached figures, the number 10 globally indicates a slot array antenna with waveguide power supply. The antenna 10 is for example part of a telecommunications system, such as for example an automatic guidance system or a radar system comprising a transmission and / or reception system operatively connected to said antenna, not shown in the figures. According to a non-limiting embodiment, the antenna 10 is an antenna operating in the KA band.

As can be seen in figure 1, the antenna 10 represented in the attached figures has a multilayer structure and comprises:

- a first layer 1 made of an electrically conductive metal (in short â € œfirst metallized layer 1â €);

- a first plate-like substrate 11 made of dielectric material;

- a second layer 2 made of an electrically conductive metal (in short â € œsecond metallized layer 2â €);

- an adhesive layer 4;

- a second plate-like substrate 12 made of dielectric material; and

- a third layer 3 made of an electrically conductive metal (in short â € œthird metallized layer 3â €).

In the particular example shown, the antenna 10 also comprises four power connectors 13, for example in waveguide, only two of which are visible in Figure 1.

Preferably, the metallized layers 1, 2 are two laminated / plated layers and more preferably electrodeposited on the two opposite faces of the first dielectric substrate 11. Preferably, the metallized layers 1, 2 are made of copper and have, for example, a thickness of about 8 -20 microns and more preferably approximately 8 microns. The first dielectric substrate 11 is for example a commercial substrate made of reinforced glass microfibre with a relatively low dielectric constant, for example included in the range 2 - 3 and more preferably equal to about 2.2. For example, the first substrate 11 has a thickness of approximately 1mm. A substrate 11 of the aforementioned type is for example currently produced by Taconicâ „¢ and marketed under the name â € œTLY â €“ 5A "and is already supplied by the aforementioned manufacturer with the electroplated copper layers 1 and 2. second dielectric substrate 12 is of the type described above with reference to the first dielectric substrate 11, with the only difference that the second dielectric substrate 12 instead of having a metallization layer on both faces has a free face, i.e. a face on on the opposite face of the second dielectric substrate 12 there is instead the metallization layer 3, which is for example a laminated / plated layer and more preferably an electroplated copper layer of the type already described with reference to metallized layers 1 and 2. The second substrate 12 is also currently produced by Taconicâ „¢ and marketed under the name â € œTLY â €“ 5A "and it is supplied by the aforementioned manufacturer with the electroplated copper layer 3 and with a free face, ie without a metallization layer. Alternatively, the second dielectric substrate 12 can be obtained with the electroplated copper layer 3 starting from a substrate with two opposite metallization layers (such as the substrate 11) by removing one of said layers.

In a further embodiment, the first 11 and the second 12 dielectric substrates are laminated dielectric substrates with surface metallization as described above but produced and marketed by Rogers Corporation under the trade name Duroidâ „¢ 5880.

The layer 4 is instead a thin adhesive layer used to hold together the two laminated dielectric substrates 11 and 12 and in particular used to glue the free face of the second substrate 12 to the free face of the metallization layer 2. For example, the adhesive layer 4 is a dielectric thin film, such as the one currently marketed under the name â € œNeltecâ „¢ 6700â €. The dielectric properties of this adhesive layer 4 are conveniently as similar as possible to those of the second dielectric substrate 12. Obviously, as an alternative to the adhesive layer 4, it is possible to use any suitable layer or film, or any other suitable means, capable of connecting / fix the dielectric substrate 12 to the second metallized layer 2 and which has dielectric characteristics compatible with the application.

With reference to Figures 2 and 3, the slot array antenna 10 comprises at least one radiant waveguide 20 comprising a plurality, or an array, of radiant slots 21. In the particular example shown, the array of slots 10 comprises, without introducing any limitation, forty radiant waveguides 20, of different lengths and having a number of slots which vary according to the respective length. It should be noted that the particular example described takes the form of a planar slot array antenna with quadrant symmetry and more precisely in a monopulse type antenna.

From now on, reference will be made in the present description to a slot array antenna 10 comprising a plurality of radiant waveguides 20.

Advantageously, the radiant waveguides 20 are made in the first dielectric substrate 11, and the first 1 and the second 2 metallized layers represent opposite confinement walls, respectively upper and lower, of the radiant waveguides 20.

Advantageously, the radiant slots 21 are openings, in the example of substantially rectangular shape, made in the first metallized layer 1, preferably by means of photolithographic techniques which provide for a selective removal of the metallization layer 1 in correspondence with the points where the radiant slots 21. Photolithographic techniques are commonly used in the production of printed circuits and belong to the knowledge of an expert in the field, for this reason they will not be further detailed in the present description. In a less preferred alternative embodiment, because currently more expensive, the aforementioned selective removal of the metallization is carried out using a laser device. It should be observed that the free face of the metallized layer 1 represents in practice the radiant surface of the antenna.

Reference is now made to figure 3, in which section A-A of the multilayer structure of figure 1 is shown, seen from the side of the arrow IV. It should be observed that in practice in Figure 3 the face of the metallized layer 2 distal from the first dielectric substrate 11 is visible. the radiant wave guide 20 to a power wave guide, so as to be able to feed said radiant wave guide 20, and therefore the radiant slots 21, with electromagnetic radiation. Advantageously, the coupling slots 31 are also openings, in the example of substantially rectangular shape, made in the second metallized layer 2, preferably by photolithographic techniques which provide for a selective removal of the metallization 2 at the points where the coupling slots 31. As can be seen in Figure 3, the coupling slots 31 are substantially rectangular openings, the inclination of which varies between the different radiant waveguides 20. Also in this case, in a form of a less preferred alternative embodiment, because currently more expensive, the aforementioned selective removal of the metallization is carried out using a laser device or by mechanical processing.

With reference to Figure 5, according to a particularly advantageous embodiment, inside the dielectric substrate 11 a plurality of through channels 22 are defined, two by two relatively close to each other and aligned in arrays of channels, which are they extend in the thickness of the dielectric substrate 11 between the first 1 and the second 2 metallization layer. These through channels 22, preferably of circular section, are internally superficially coated, or alternatively entirely filled, with an electrically conductive material, such as copper for example. Again with reference to Figure 5, it should be noted that each radiant guide 20 comprises lateral confinement walls 23, 24. These lateral confinement walls 23, 24 are each formed by a respective array of through channels 22. It should be observed that if the distance minimum between two adjacent pass-through channels 22 is relatively small compared to the working wavelength of the antenna 10 (for example equal to about 1/20 of this), the confinement walls 23, 24, despite being made up of discrete and spaced elements 22, can be considered as approximately continuous confinement side walls.

The through channels 22 are obtained for example by perforating, for example by drilling, the first metallized layer 1, the first dielectric substrate 11 and the second metallized layer 2. The channels 22 thus produced are then preferably plated with an internal surface coating of copper.

For example, the diameter of the channels 22 is equal to about 0.4 mm and the tolerance of the drilling machining is conveniently equal to / - 0.005mm. On the position of the channel holes 22, the tolerance is conveniently equal to / - 0.03 mm. Clearly these processing parameters can be varied according to the working frequency for which the slot array antenna 10 is designed.

The processing steps described above with reference to the formation of the radiant waveguides 20, the radiant slots 21 and the coupling slots are carried out on a first dielectric substrate 11 laminated / plated on both faces, before coupling said first substrate dielectric 11, by means of an adhesive layer 4, to the dielectric substrate 12 laminated / plated only on one of the two faces. Subsequently, the first 11 and the second 12 dielectric substrate are coupled, by means of the adhesive layer 4, so that the unplated face of the second dielectric substrate 12 faces the metallization layer 2.

According to an embodiment, the slot array antenna 10 comprises at least one supply waveguide 40, 41, 42, 43 of the radiating guides 20 operatively coupled to the latter by means of the coupling slots 31. In the particular example shown in the figures, four power waveguides 40, 41, 42, 43 are provided, each designed to independently power a respective group of ten radiant waveguides 20. As can be seen, the power waveguides 40, 41, 42, 43 are oriented transversely with respect to the radiant waveguides 20. From now on we will refer, without introducing any limitation, to the case in which the The slot array antenna 10 comprises a plurality of power waveguides 40, 41, 42, 43.

The power wave guides 40, 41, 42, 43 are advantageously made in the second dielectric substrate 12, preferably by making blind grooves 44-48, preferably by mechanical processing and alternatively by laser processing, conveniently two by two parallel, in the second dielectric substrate 12, preferably starting from the metallization layer 3, crossing entirely this layer 3, also crossing entirely the second dielectric substrate 12, the adhesive layer 4 and arriving to partially affect (i.e. partially cross) also the second metallized layer 2. This explains the reason why the power wave guides 40, 41, 42, 43 are (partially) visible in figure 3, as the blind grooves 44-48 which partially cross the layer of metallization 2.

As can be seen in figure 6, which shows a lateral section of the portion of antenna 10 delimited by the dashed square 35 in figure 3 (section along the Y-Y axis), in which a section is practically visible transversal of the power wave guide 42, the blind grooves 44-48 thus obtained are superficially coated, that is, plated, with a conductive metallization 60 to form the lateral confinement walls of the power wave guides 40- 43. As can be seen in Figure 6, it is clear that the upper and lower confinement walls of the power waveguides 40-43 will be made up of metallized layers 2 and 3.

According to one embodiment, the slot array antenna 10 further comprises at least one input slot 49 for each power waveguide 40-43. It should be noted that in figure 6 the input slot 49 has been represented purely by way of example, since from the joint observation of figures 3 and 4 it can be observed that in the section along the Y-Y axis no slot is provided for entrance 49.

Preferably, the inlet slots 49 are openings, for example of a substantially rectangular shape, made in the third metallized layer 3, preferably by means of photolithographic techniques which provide for a selective removal of the metallization layer 3 at the points where the slots are to be made. of entry 49.

As can be seen from the joint observation of Figures 2-4, the slot array antenna further includes a plurality of through channels 50 which extend from the free face of the metallized layer 1 to the free face of the metallized layer 3. Such through channels 50 are aligned in arrays of channels, arranged two by two at a relatively small distance from the wavelength and are coated or filled with conductive material, such as copper, to separate two or more dâ € ™ guides from each other. ™ power wave 40-43. With reference to Figure 4, it can be observed how an array 50 of through channels divides the power waveguide identified by the blind and plated grooves 46, 47 into two power waveguides 40, 41 and how, in a similar way , an array 50 of through channels divides the power waveguide identified by the blind and plated grooves 44, 45 into the two power waveguides 42, 43.

As can be seen in Figures 3 and 4, the slot array antenna 10 also comprises a plurality of blind holes 51, to allow connectors, for example in waveguides, to be attached to the same antenna, suitable for powering the power waveguides 40-43. These blind holes, conveniently, are not plated and extend from the metallization layer 2 to the metallization layer 3. In the specific example shown in the figures, four groups are provided comprising four holes 51 each to allow coupling to each of the wave guides power supply 40-43 a respective connector.

With reference to Figure 7, an example of a method for manufacturing a slot array antenna 10 as described above will be described below.

The process, globally indicated with 100, comprises a first step 101 of making available the first plate-like dielectric substrate 11 having two opposing metallized faces, i.e. provided with two surface metallization layers 1, 2. A dielectric substrate 11 of the type indicated above à It has already been described with reference to figures 1-6 and therefore will not be further detailed. Similarly, the first step 101 comprises an operation of making available the second plate-like dielectric substrate 12, as already described above, provided with a free face and an opposite metallized face, that is, coupled to the metallization layer 3.

The method 100 also comprises a step 102 including an operation of making at least one array of radiating slots 21 by selectively removing, preferably photolithographically, said portions of the first metallized layer 1 and an operation of making at least one coupling slot 31 by selectively removing, preferably photolithographically, at least a portion of the second metallized layer 2. As already mentioned previously, in an alternative embodiment the selective removal of portions of the metallized layers 1 and 2 takes place by means of laser techniques.

The process 100 also comprises a step 103 comprising an operation of making a plurality of through channels 22 extending from the first 1 to the second 2 metallized layer and an operation of superficially coating the internal walls of said channels 22, or of filling said through channels 22 with an electrically conductive material, so that the through channels 22 thus filled or coated define lateral confinement walls of at least one radiant waveguide 10, the first 1 and the second 2 metallization layers representing two further confinement walls opposite of the aforesaid at least one radiant wave guide 20. Preferably, the aforesaid through channels 22 are obtained by perforating the first metallized layer 1, the first dielectric substrate 11 and the second metallized layer 2, for example by means of a mechanical perforation device.

According to a currently preferred embodiment, the above steps or operations are performed in the above sequence:

- realization and metallization (by drilling and subsequent coating or filling) of the through channels 22;

- making two photoengraving masks, accurate alignment of said masks with respect to the through channels 22 and subsequent photoengraving of said masks respectively on a free surface of said first layer 1 and of said second metallization layer 2;

- realization and metallization (by drilling and subsequent coating or filling) of the through channels 22;

- etching for the selective removal of portions of the first 1 and second 2 metallization layer on the basis of the aforementioned photoengraving masks for the realization of the radiating and coupling slots.

Process 100 further comprises:

- a step 104 of coupling said second dielectric substrate 12 to the second metallized layer 2 (on the side of the non-metallized face of the second dielectric substrate 12) by interposition of a layer 4 of dielectric adhesive;

- a step 105 of making blind grooves 44-47 which extend from the third metallized layer 3 up to at least partially involve the second metallized layer 2 and of coating the internal walls of said blind grooves with a metallization or alternatively of filling said blind grooves with metallic material to define lateral confinement walls of one or more feed guides 40-43.

According to a particularly advantageous embodiment, after having made the coupling slots 31 and before making the two substrates 11, 12 integral, an operation is carried out to selectively increase the thickness of the second metallized layer 2, for example galvanically, in the areas in which it has not been removed to make the coupling slots 41. For example, this growth operation is such as to bring the metallized layer 2 from a thickness of about 10 microns to a thickness of about 40 microns. In this way, the step 105 of making the blind grooves 44-47 can be carried out less accurately, for example with a cutter, without running the risk of completely perforating the metallized layer 2.

The process 100 also comprises a step 105 of making at least one inlet slot 49 preferably by photolithographically removing at least a portion of the third metallized layer 3 and preferably also a step of making one or more arrays of through channels 50 which cross the entire multilayer structure as realized above and to internally metallize said arrays of through channels 50 to divide at least one power waveguide (40-43) into two or more operationally separate power waveguides.

The method 100 also preferably comprises a step 106 of making one or more groups of non-through holes 51 to couple one or more inlet connectors to the multilayer structure as obtained above from the side of the third metallization layer 3.

The process 100 also preferably comprises a step 107 of selective plating of the exposed metallized parts with a layer of protective material, for example with gold.

From what has been described above, it is therefore possible to understand how a slot array antenna of the type described above can be made with a less complex or expensive process than what currently occurs in the state of the known art. It should also be noted that the antenna 10 has a compact structure in terms of vertical dimensions and is relatively light.

It should also be noted that since the radiant guides are made of a substrate of dielectric material (that is, these guides are `` loaded ''), these guides can have a relatively small width (width means the longer side of the guide section) and allow to realize positioning distances of two consecutive slots inside the same guide which, at the same working frequency, are relatively reduced compared to those of the air guides of the known art. For this reason, therefore, with the same planar dimensions of the antenna, it is possible to create an antenna having a greater number of guides and / or guides with a greater number of radiant slots, thus obtaining an improvement in performance in terms of planar dimensions. directivity and earnings.

Without prejudice to the principle of the invention, the forms of implementation and construction details may be widely varied with respect to what has been described and illustrated purely by way of non-limiting example, without thereby departing from the scope of the invention as defined in the attached claims.

For example, in a first embodiment variant not shown in the figures, the antenna 10 has a hybrid structure, comprising the dielectric substrate 11 and the first metallized layer 1 (with the radiant slots 21 and the through channels 22 made as described above ). The metallized layer 2, in which the coupling slots 31 are made, for example in this case by mechanical or laser processing, in this case is made of brass or aluminum and has a greater thickness than the layer 1 so as to allow couple to this layer a base comprising traditional power waveguides with a â € œUâ € section.

In a second embodiment variant, schematically represented in figure 8 in lateral section, to the antenna 10 as described with reference to figures 1-6 in which the connectors 13 are not provided, a monopulse comparator 80 is operationally coupled on the side of the layer 3 connected to the input slots 49. According to a particularly advantageous embodiment, the monopulse comparator 80 is a waveguide comparator, made on a dielectric substrate 81 similar to the substrate 11 described above (therefore provided with two layers of metallization 82 and 83) in which the lateral guide walls are made with arrays of through channels 22 of the type described above with reference to the radiant guides 20. This comparator 80 can be coupled to the layer 3 for example by means of a layer (not shown in figure 8) similar to the adhesive layer 4 described above. According to an alternative embodiment not shown in the figures, the monopulse comparator is a conventional comparator made of an aluminum block and has hollowed guide walls and is fixed to the metallized layer 3 which can conveniently be made in this case in aluminum and thicker in order to allow stable coupling with the dial gauge.

With reference to Figure 9, in accordance with a third particularly advantageous embodiment variant, two multilayer antennas of the type described above with reference to Figures 1 and 6, respectively upper and lower antenna, designed and sized to operate in two different frequency bands, are superimposed and coupled face to face. To allow the radiant slots 91 of the lower antenna to have access to the face 1 of the antenna, pass-through channels are previously made, coated with conductive material, which completely pass through the upper antenna and are arranged, as shown in figure 9 , so as not to interfere with the radiant waveguides 20 and the power supply of the upper antenna. These through channels therefore represent an outlet on the face 10 of the radiating slots of the lower antenna, and therefore are equal in number to the number of radiating slots of the lower antenna and are arranged aligned with them. As can be seen, the through channels 91 communicating with the slots of the lower antenna are made by exploiting the interspaces present between adjacent radiant waveguides 20 of the upper antenna.

Similarly, in the lower antenna there are pass-through channels that do not interfere with the guides of this antenna, in the same number and in a corresponding position as the input slots 49 of the upper antenna 10. In order for these channels not to affect the performance of the upper antenna, the the thickness of the channel must be conveniently such that the impedance seen from the upper ground plane looking towards the channel is close to zero.

The embodiment just described above can be implemented thanks to the fact that since the radiant guides are made in the substrate of dielectric material (i.e. these guides are ... loaded ...), these guides have a reduced width at the same working frequency compared to the guides in the air of the known art, and therefore, with the same planar dimensions of the antenna, they can be distant from adjacent guides by a sufficient quantity to create pass-through channels 91 between adjacent guides without degrading the performance of the antenna due to the grating phenomenon lobes.

Claims (13)

CLAIMS 1. Slot array antenna (10) with waveguide power supply comprising at least one radiant waveguide (20) comprising an array of radiant slots (21) and at least one coupling slot (31) adapted to power a dictates at least one radiant waveguide (20) a radio frequency electromagnetic radiation, the antenna (10) having a multilayer structure and comprising: - a first plate-like substrate (11) in dielectric material comprising a first metallized layer (1) and a second metallized layer (2) respectively arranged on a first face and an opposite second face of said plate-like substrate (11), the first (1 ) and the second (2) metallized layer representing respectively a first confinement wall and a second opposite confinement wall of said radiant waveguide (20), said radiant slots (21) are openings made in said first metallized layer ( 1) and said at least one coupling slot (31) is an opening made in said second metallized layer (2); - at least one supply waveguide (40-43) of said radiant guide (20) operatively coupled to the latter through said coupling slot (31), the antenna further comprising a second plate-like substrate (12) made of material dielectric having a third face coupled to said second metallization layer, the power waveguide (40-43) being formed in the thickness of the second plate-like substrate (2); characterized by the fact that the antenna (10) comprises a dielectric adhesive layer (4) suitable for holding together said first (11) and said second substrate (12), said dielectric adhesive layer (4) being interposed between the second metallized layer (2) and said third face of the second plate-like substrate (12), said second metallized layer representing a confinement wall of said feed waveguide (40-43). Slot array antenna (10) according to claim 1, wherein the radiating (21) and coupling (31) slots are openings defined in said metallized layers (1,2) for selective photolithographic removal of portions of said layers metallics. Slot array antenna (10) according to any one of the preceding claims, further comprising a plurality of through channels (22) extending in the thickness of said first substrate (11) between said first (1) and said second (2) ) metallized layer, said through channels (22) being internally coated or filled with electrically conductive material, and in which the radiant waveguide (20) comprises lateral confinement walls, said lateral confinement walls each comprising a respective array of said through channels (22). Slot array antenna (10) according to claim 1, wherein said second substrate (2) comprises a fourth face opposite to said third face and wherein the antenna (10) further comprises a third metallized layer (3) arranged on said fourth face, said third metallized layer (3) representing a second confinement wall of the supply waveguide (40-43) opposite said first confinement wall. Slot array antenna (10) according to claim 4, comprising at least a first and a second blind groove (44-47) extending from a free surface of said third metallization layer (3), through said second substrate (12) until partially involving said second metallization layer (2), said first and said second groove respectively comprising a first wall and a second wall covered by a metallization layer, in which said first and said second wall represent lateral walls of confinement of the power waveguide (40-43). Slot array antenna (10) according to claims 4 or 5, further comprising at least one array of through channels (50), which extend from said first (1) to said third (3) metallization layer, coated or filled with a conductive metallic material, said at least one array of through channels (51) being adapted to divide said feed waveguide (40-43) into two or more feed waveguides. Slot array antenna (10) according to any one of claims 4 to 6, further comprising through channels (91) extending from the first metallized layer (1) to the third metallized layer (3), internally coated with a material electrically conductive, provided in such positions as to be able to couple to said antenna (10) from the side of said third metallized layer (3) a further slot array antenna intended to operate in a different band, said pass channels being suitable for facing each other. radiating slots of said further antenna and being substantially non-interfering with said radiating guides (20), being interposed between adjacent radiating guides (20). 8. Process (100) for making a slot array antenna (10) comprising: a step (101) of making available a first plate-like dielectric substrate (11), equipped with two opposite layers of surface metallization (1, 2) and suitable for hosting at least one radiant waveguide, and a second plate-like dielectric substrate (12 ), having a free face and an opposite face coated with a third metallized layer (3), said second substrate being suitable for hosting at least one supply waveguide (40-43) of said radiant waveguide; - a step (102) of making at least one array of radiating slots (21) by selectively removing portions of said first metallization layer (1) and an operation of making at least one coupling slot (31) by selectively removing at least a portion of said second metallization layer (2); characterized by the fact that the process comprises a step of coupling said second substrate (12) to the second metallized layer (2) of the first substrate (11) by interposition of a dielectric adhesive layer (4), so that said second metallized layer (2) represents a wall confinement of said power waveguide (40â € "43) - Process (100) according to claim 8, further comprising a step (103) including an operation of making a plurality of through channels (22) extending from the first (1) to the second (2) metallization layer and an operation to superficially cover the internal walls of said channels (22), or to fill said through channels (22) with an electrically conductive material, so that the through channels (22) thus filled or coated define lateral confinement walls of at least one guide wave (20), the first (1) and the second (2) metallization layer representing two further opposing confinement walls of said radiant waveguide. Process (100) according to claim 9, wherein the second plate-like dielectric substrate (12) has a free face and an opposite face coated with a third metallized layer (3), and wherein the process (100) further comprises: - a step (105) of making blind grooves (44, 47) which extend from the third metallized layer (3) up to at least partially involve the second metallized layer (2) and of coating the internal walls of these blind grooves with a metallization , or to fill such grooves with electrically conductive metallic material, to define lateral confinement walls of one or more supply waveguides (40-43). Process (100) according to claim 10, further comprising a step of selectively increasing the thickness of said second metallized layer (2) before carrying out said coupling step (104). 12. Process according to claim 10, further comprising a step of making through channels (91) extending from the first metallized layer (1) to said third metallized layer (3), of internally coating said channels with an electrically conductive material, for couple to said antenna (10) from the side of said third metallized layer (3) a further slot array antenna intended to operate in a different band, said pass channels representing radiating slots of said further antenna and being substantially interfering with said radiating guides and power supply being arranged in the interspaces present between radiant waveguides (20). 13. Process according to any one of the preceding claims from to 12, wherein said selective removal is carried out photolithographically.