Microwave component with at least one filler integrated into the carrier substrate

Abstract

A microwave component (40), said component comprising: - at least one waveguide (42) comprising a propagation zone (48) for propagation of an electromagnetic wave, the propagation zone extending along a propagation axis; - a carrier substrate (44) made of dielectric material suitable for ensuring the mechanical rigidity of the component; - the carrier substrate comprising a first layer made of dielectric material having a first upper electrically conductive surface (44.1) and a first lower electrically conductive surface (44.2) covering an upper face and a lower face of the carrier substrate, respectively; - at least one absorption zone (47) extending into the carrier substrate in order to guide the propagation of electromagnetic waves coming from the waveguide into the substrate in order to absorb the energy of the waves or to attenuate the energy of the waves, the absorption zone being delimited by the first upper electrically conductive surface (44.1), the first lower electrically conductive surface (44.2) and two spaced-apart lateral boundaries (46) able to prevent the passage of an electromagnetic wave; - a feed element (49.1, 49.2) positioned at the entrance of the absorption zone (47) and configured to collect at least part of the electromagnetic wave coming from the propagation zone (48) of the at least one waveguide and to inject it into the absorption zone (47).

Description

MICROWAVE COMPONENT WITH AT LEAST ONE LOAD INTEGRATED INTO THE SUPPORT SUBSTRATE Technical field

[0001] The present invention relates to the field of microwave components based on microwave transmission lines, and in particular that of microwave components based on transmission lines integrated into the substrate or waveguide integrated into the substrate. Prior art

[0002] In microwave and millimeter wave systems, it is known to use 3D rectangular metal waveguides (RWGs) to produce high-performance microwave components. However, RWGs are bulky, expensive, and difficult to integrate into planar structures.

[0003] To reduce manufacturing costs and enable mass production, microwave components are made using planar technology.

[0004] Figure 1 shows an example of an embodiment of a transmission line formed by a microstrip 5 separated from a conductive layer 3 by a dielectric layer 2. The propagation zone 8 is located under the microstrip. The assembly can be supported by a support substrate 4.

[0005] Figure 2 shows another exemplary embodiment of a coplanar transmission line 10 formed by a conductive track 11 bordered on each side by a return line 12, 13. The propagation zone 18 is located under the central track 11, in a dielectric layer 15 sandwiched between the tracks and a conductive layer 16. Vias 16, 17 extend between the conductive layers through the dielectric layer 15 to define the pattern of the propagation zone. The assembly is supported by a support substrate 14.

[0006] However, these microwave components generate losses and energy leaks through high-frequency radiation.

[0007] In order to improve the performance of microwave components while providing low-cost, highly integrated, compact, and mass-producible microwave components, microwave components based on substrate integrated waveguide (SIW) technology have been proposed.

[0008] Figure 3 shows an illustration of an example of the structure of a SIW waveguide 20 configured to guide an electromagnetic wave along a propagation axis XX. It comprises a central layer 21 made of a dielectric material and of small thickness, an upper electrically conductive layer 22 and a lower electrically conductive layer 23 covering the two opposite faces of the central dielectric layer 21. The three layers extend in an XY plane, defined by the propagation axis XX and by a transverse axis YY orthogonal to the propagation axis XX. The upper conductive layer 22 and the lower conductive layer 23 are arranged at a distance from each other, on either side of the dielectric layer 21, in contact with the dielectric layer. Thus, the three layers are stacked along an axis Z.

[0009] The conductive layers are made of copper, for example. The dielectric layer is made of epoxy resin, for example.

[0010] The dielectric layer 21 also comprises a plurality of metallized holes, each hole forming a via 26, 27 between the first and second conductive layers. The plurality of vias thus forms two distinct rows, at a distance from one another. Thus, the component comprises a propagation zone 28 in the dielectric layer 21, delimited, according to the thickness, between the upper and lower conductive layers 22, 23 and, according to the width, between the plurality of metallized holes. The propagation zone 28 extends along the propagation axis XX, corresponding to a zone in which the electromagnetic waves are confined. The pattern formed by the plurality of metallized holes therefore defines the radiofrequency function performed by the microwave component, which may be, for example, a transmission line, a filter, a coupler, an antenna, a power divider or a power combiner.The component also includes a thick support substrate 24.

[0011] This technology benefits from low manufacturing costs and is easily integrated into a PCB-based system. The components generally have a very lightweight structure, while allowing high integration density in systems. Thus, such SIW components are more compact and less expensive than conventional rectangular waveguides.

[0012] Recently, in order to reduce the dielectric loss of the propagation medium, while maintaining low cost and high integration, Air-filled Substrate Integrated Waveguide (AFSIW) technology has been proposed. AFSIW or hollow SIW, like SIW technology, is a multi-layer structure based on PCB technology.

[0013] Figure 4 shows an illustration of an example of the structure of an AFSIW waveguide 30. The structure of an AFSIW waveguide comprises an upper layer 31 of dielectric material and a lower layer 32 of dielectric material. The two faces of the upper dielectric layer 31 are each covered respectively by an upper conductive layer 33 and a lower conductive layer 35. A longitudinal cavity 38 is produced in the lower dielectric layer 32. The internal side walls 38.1, 38.3 and the lower wall 38.2 of the cavity are metallized. Thus, the component comprises a propagation zone 38 in the lower dielectric layer 32, delimited, according to the thickness by the lower conductive layer 35 and the internal lower wall 38.2 of the cavity, and, according to the width, by the metallized internal side walls 38.1, 38.3 of the cavity.The propagation zone 38 extends along the propagation axis XX, corresponding to a zone in which the electromagnetic waves are confined. The pattern formed by the cavity therefore defines the radiofrequency function performed by the microwave component, which may be, for example, a transmission line, a filter, a coupler, an antenna, a power divider or a power combiner. The component may further comprise a dielectric substrate 34 which makes it possible to support the assembly and make it more rigid. Alternatively, the component is supported by the lower dielectric layer 32 which may have a suitable thickness.

[0014] However, the microwave components shown in Figures 1 to 4 are not entirely satisfactory. Indeed, when termination loads are required in a radio frequency circuit design, they are added externally or into the structure manually. The structure must then be manually shielded. Thus, the termination is not fully integrated, and is therefore not suitable for mass production. This solution also results in an increase in the size of the structure due to the need for a fixing system, and the risk of a loss of efficiency related to radio frequency leakage due to the presence of external interfaces. The introduction of this additional step also results in an increase in the production cost.

[0015] Furthermore, the inventors note that in the structures of microwave components currently implemented, the main radiofrequency function uses only a small percentage of the available volume of the printed circuit board. Indeed, the substrate which represents a large part of the printed circuits only contributes to increasing the robustness of the overall structure. For example, as shown in Figures 1 to 4, whether it is planar technology or technology with a waveguide integrated in the dielectric layers, the substrate layers 4, 14, 24 and 34 are not used. Their main function is to support the microwave component and make it rigid.

[0016] Therefore, there is a need to find a solution allowing the easy integration of termination loads or absorbers in microwave components with a planar structure, based on microwave transmission lines, and in particular microwave components based on transmission lines integrated into the substrate or waveguide integrated into the substrate, without incurring additional manufacturing costs, while maintaining the performance required for these components. Summary

[0017] This disclosure improves the situation.

[0018] The present disclosure relates to a microwave component, said component comprising: at least one waveguide comprising a propagation zone for an electromagnetic wave, said propagation zone extending along a propagation axis; - a support substrate made of dielectric material suitable for ensuring the mechanical rigidity of said component; - said support substrate comprising a first layer made of dielectric material having a first upper electrically conductive surface and a first lower electrically conductive surface respectively covering an upper face and a lower face of said support substrate; - at least one absorption zone extending into the support substrate for guiding the propagation of electromagnetic waves from said waveguide into the substrate to absorb wave energy or attenuate wave energy, said absorption zone being delimited by the first upper electrically conductive surface, the first lower electrically conductive surface and two spaced lateral boundaries adapted to prevent the passage of an electromagnetic wave; - a feed element positioned at the entrance to said absorption zone and configured to take at least a portion of the electromagnetic wave coming from said propagation zone of said at least one waveguide and to inject it into said absorption zone.

[0019] The features set out in the following paragraphs may, optionally, be implemented independently of each other or in combination with each other.

[0020] The lateral boundaries of the absorption region are formed by a plurality of metallized through holes extending through the support substrate to electrically connect the first upper electrically conductive surface and the first lower electrically conductive surface.

[0021] The plurality of metallized through holes defines a pattern having the shape of a meander.

[0022] The plurality of metallized through holes defines a pattern having the shape of a ring.

[0023] The first layer made of dielectric material has a thickness of between 0.2 mm and 10 mm, preferably between 0.5 mm and 6 mm.

[0024] According to one embodiment, said at least one waveguide comprises a second layer of dielectric material having a second electrically conductive upper surface and a second electrically conductive lower surface, said second electrically conductive lower surface being in electrical contact with said first electrically conductive upper surface of said support substrate, the propagation zone being defined in said second layer of dielectric material and delimited by the second electrically conductive upper surface, the second electrically conductive lower surface and by a plurality of metallized through holes extending through said second layer of dielectric material.

[0025] According to an exemplary embodiment, said power supply element comprises a first slot made in the second lower conductive surface and a second slot made in the first upper conductive surface, the two slots being aligned and arranged opposite the entrance to the absorption zone.

[0026] Preferably, the power element comprises a set of metallized steps formed in the support substrate, at the interface between the support substrate and the first conductive lower surface.

[0027] According to another embodiment, said at least one waveguide comprises a second layer of dielectric material having a second electrically conductive upper surface and a second electrically conductive lower surface, said second electrically conductive lower surface being in electrical contact with said first electrically conductive upper surface of said support substrate, said propagation zone comprises an internal cavity made in the support substrate, the side walls and the lower wall of said cavity being metallized, the propagation zone being delimited by the second electrically conductive lower surface of the second layer of dielectric material and the metallized walls of the cavity.

[0028] According to an exemplary embodiment, the feed element comprises a hollow zone made in the support substrate, said hollow zone being formed from an extension of one end of the internal cavity of the waveguide.

[0029] Preferably, the hollow region comprises a first end forming an interface with the end of the cavity and a second end in the form of a tip penetrated into the absorption region of the substrate.

[0030] Preferably, the end of the cavity located at the interface with the first end of the hollow zone comprises a set of metallized steps to achieve impedance matching between the cavity and the absorption zone.

[0031] According to another exemplary embodiment, said feed element comprises at least one slot made in one of the walls of the internal cavity of the waveguide. Brief description of the drawings

[0032] Other features, details and advantages will become apparent upon reading the detailed description below, and upon analyzing the attached drawings, in which: Fig. 1

[0033] [Fig. 1] Figure 1 is a sectional view of a microwave component comprising a mircoriban transmission line, in a plane orthogonal to the propagation axis X-X; Fig. 2

[0034] [Fig. 2] Figure 2 is a sectional view of a microwave component comprising a coplanar transmission line, in a plane orthogonal to the propagation axis XX;

[0035] Fig. 3

[0036] [Fig. 3] Figure 3 is a sectional view of a microwave component of the SIW type, in a plane orthogonal to the propagation axis XX; Fig.4

[0037] [Fig. 4] Figure 4 is a sectional view of a microwave component of the AFSIW type, in a plane orthogonal to the propagation axis XX; Fig.5

[0038] [Fig. 5] Figure 5 is a sectional view of an isolated power combiner / divider microwave component according to one embodiment of the invention, in a plane orthogonal to the propagation axis XX;

[0039] [Fig. 6] Figure 6 shows respectively: (a) a top view of the second upper conductive surface of the microwave component of Figure 5, (b) a top view of the second lower conductive surface, and (c) a top view of the first upper conductive surface; Fig.7A

[0040] [Fig. 7A] Figure 7A shows the magnitude of the electric field in the microwave component operating in a normal usage configuration, with the signal applied to port 1 and the signal output at ports 2 and 3; Fig.7B

[0041] [Fig. 7B] Figure 7B represents the amplitude of the electric field in the microwave component operating in a situation in which a part representing substantially 50% of the signal entering port 2 is taken at the junction and injected into the absorption zone made in the lower substrate layer, port 3 is thus isolated and protected; Fig.7C

[0042] [Fig. 7C] Figure 7C represents the amplitude of the electric field in the microwave component operating in a situation in which a part representing substantially 50% of the signal entering port 3 is taken at the junction and injected into the absorption zone made in the lower substrate layer, port 2 is thus protected; Fig.7D

[0043] [Fig. 7D] Figure 7D shows a view of the electric field amplitude in the absorption region formed in the lower substrate layer from the lower face of the microwave component; Fig.8

[0044] [Fig. 8] Figure 8 is a sectional view of a microwave power coupler according to another embodiment of the invention, in a plane orthogonal to the propagation axis XX; Fig.9

[0045] [Fig. 9] Figure 9 shows respectively: (a) a top view from the upper surface of the upper conductive layer of the upper dielectric layer of the coupler of Figure 8, (b) a top view from the upper surface of the lower conductive layer of the upper dielectric layer of the coupler of Figure 8, Figure 8, and (c) a top view from the upper surface of the upper conductive layer of the lower dielectric layer of the microwave component of Figure 8; Fig. 10A

[0046] [Fig. 10A] Figure 10A shows the magnitude of the electric field in the power coupler of Figure 8 operating in a normal use configuration, with the signal applied to port 1 and the signal output at ports 2 and 3; Fig. 10B

[0047] [Fig. 10B] Figure 10B represents the amplitude of the electric field in the microwave component operating in a situation in which a portion representing substantially 50% of the signal coming from port 3 is taken at port 4 and injected into the absorption zone made in the lower substrate layer, port 2 is thus isolated and protected; Fig. 10C

[0048] [Fig. 10C] Figure 10C represents the amplitude of the electric field in the microwave component operating in a situation in which a portion representing substantially 50% of the signal coming from port 2 is taken at port 4 and injected into the absorption zone made in the lower substrate layer, port 3 is thus isolated and protected; Fig. 10D

[0049] [Fig. 10D] Figure 10D shows a view of the electric field amplitude in the absorption region formed in the lower substrate layer from the lower face of the microwave component; Fig. 11

[0050] [Fig. 11] Figure 11 is a sectional view of a microwave component produced using integrated hollow SIW technology according to an embodiment of the invention, in a plane orthogonal to the propagation axis XX; Fig. 12

[0051] [Fig. 12] Figure 12 shows a perspective and top view of a Y-shaped cavity in a hollow SIW microwave component with an absorption zone integrated in the support substrate according to one embodiment of the invention; Fig. 13A

[0052] [Fig. 13A] Figure 13A shows the magnitude of the electric field in the microwave component of Figure 12 operating in a normal use configuration, with the signal applied to port 1 and the signal output at ports 2 and 3; Fig. 13B

[0053] [Fig. 13B] Figure 13B shows the amplitude of the electric field in the microwave component operating in a situation in which part of the signal energy from port 3 is taken at the slit and injected into the absorption zone made in the lower substrate layer, thus port 2 is protected; Fig. 13C

[0054] [Fig. 13C] Figure 13C shows the electric field amplitude in the microwave component operating in a situation where part of the signal energy from port 2 is taken at the junction and injected into the absorption zone made in the lower substrate layer, thus port 3 is protected; Fig. 14

[0055] [Fig. 14] Figure 14 shows a top perspective view of a Y-shaped cavity of a hollow SIW microwave component with an absorption area integrated into the support substrate according to a variation of Figure 12 and an enlarged view of the central region of the guide; Fig. 15A

[0056] [Fig. 15A] Figure 15A shows the magnitude of the electric field in the microwave component of Figure 14 operating in a normal use configuration, with the signal applied to port 1 and the signal output at ports 2 and 3; Fig. 15B

[0057] [Fig. 15B] Figure 15B shows the electric field amplitude in the microwave component operating in a situation where the signal comes from port 3 and a part of the signal energy from port 3 is taken at the central area via the slit and injected into the absorption area made in the supporting substrate layer, thus port 2 is isolated and protected; Fig. 15C

[0058] [Fig. 15C] Figure 15C represents the amplitude of the electric field in the microwave component operating in a situation in which the signal comes from the port 2 and part of the signal energy from port 2 is taken from the central area via the slit and injected into the absorption area made in the lower substrate layer, port 3 is thus isolated and protected. Fig. 16A

[0059] [Fig. 16A] Figure 16A is a top perspective view of a channel-shaped cavity of a hollow SIW microwave component without the upper layers, integrating an absorption zone in the support substrate according to another embodiment, the end of the channel forming a feed element opening into an absorption zone integrated in the support dielectric substrate of the component; Fig. 16B

[0060] [Fig. 16B] Figure 16B shows an enlarged top view of the impedance matching and feed area between the cavity and the absorption area of ​​Figure 16A; Fig. 17

[0061] [Fig. 17] Figure 17 is a representation of the electric field magnitude in the feed element and absorption region of Figure 16A when injecting a signal from port 1 into the absorption region. Description of the embodiments

[0062] The present invention relates to a microwave component comprising a waveguide comprising a propagation zone for an electromagnetic wave, the zone extending along a propagation axis in at least one dielectric material for propagating a signal between two ports.

[0063] In the context of the present invention, the microwave component or microwave transmission line designates any component requiring the implementation of a radiofrequency load. The microwave component of the present invention may be, for example, a coupler, a filter, an antenna, a divider, a combiner, or even an isolator.

[0064] As used herein, the term "radio frequency load" or "termination load" refers to elements used in a microwave transmission component to absorb energy and prevent RF signals from reflecting from an open or unused port. Ports are typically terminated with a load whose characteristic impedance is the same as that of the transmission line. Any multi-port RF system, not all of whose ports are in use, must be terminated so that any signal incident on those ports is absorbed. If a port is not terminated, the Signals can reflect back into the system, which can introduce distortion and other unwanted effects. Loads are used in couplers, hybrids, isolators, test equipment, and in systems where a port needs to be terminated. There are three main types of RF terminations: coaxial, waveguide, and chip. In this disclosure, loads are used to terminate waveguide ports.

[0065] Within the scope of the present invention, the microwave component can be produced using planar technology for any type of planar transmission line and covers in particular the micro-strip components and the coplanar components illustrated in Figures 1 and 2. The components can also be produced using stripline technology.

[0066] In the context of the present invention, the microwave component may be produced using substrate integrated waveguide technology. In the remainder of the description, such components will be referred to as “SIW components”.

[0067] In the context of the present invention, the microwave component may be produced using hollow waveguide technology integrated into the substrate. In the remainder of the description, such components will be referred to as hollow SIW.

[0068] According to the embodiments of the invention, the microwave component further comprises: - a support substrate made of dielectric material suitable for ensuring the mechanical rigidity of said component, the support substrate having an upper electrically conductive surface and a lower electrically conductive surface covering an upper face and a lower face of the support substrate; - an absorption zone extending into the support substrate for guiding the propagation of electromagnetic waves from the waveguide into the substrate to absorb wave energy or attenuate wave energy; and - a feed element positioned at the entrance to said absorption zone and configured to take at least a fraction of the electromagnetic wave coming from said propagation zone of said at least one waveguide and to inject it into said absorption zone.

[0069] Thus, thanks to the direct integration of this absorption zone into the support substrate, it is no longer necessary to manually add the RF load to the outside or into the component structure and to manually shield the structure. Such a component can be adapted to mass production and allows to limit the production cost. In addition, integrating the load into the substrate no longer requires the use of a fixing system to fix the load to the component structure, thus allowing to limit the size of the structure. The absence of interfaces also helps to limit the risks of loss of efficiency and electromagnetic compatibility linked to radiofrequency leaks.

[0070] According to another technical advantage, the integration of the absorption zone in the substrate thus makes it possible to exploit the substrate which represents a large part of the printed circuits.

[0071] An example of a first embodiment of a microwave component 40 according to the invention is illustrated in FIG. 5.

[0072] The microwave component 40 is here of the type with a guide integrated into the SIW substrate.

[0073] The component 40 comprises a waveguide 42 capable of guiding an electromagnetic wave along at least one propagation axis, the electromagnetic wave having a predetermined wavelength, a support substrate 44 made of a dielectric material suitable for ensuring the mechanical rigidity of the component, an absorption zone 47 extending in the support substrate to guide the propagation of electromagnetic waves coming from the waveguide in the substrate in order to absorb the energy of the waves or to attenuate the energy of the waves, and a feed element 49.1, 49.2 positioned at the entrance to the absorption zone and configured to take at least a fraction of the electromagnetic wave coming from the propagation zone and to inject it into the absorption zone.

[0074] The support substrate comprises a first layer 44 of dielectric material that extends in an XY plane. The first layer 44 has a first electrically conductive upper surface 44.1 and a first electrically conductive lower surface 44.2.

[0075] The waveguide 42 comprises a second layer of dielectric material 41 in which a propagation zone 48 is defined. The second layer of dielectric material 41 extends in the XY plane. The second layer of dielectric material has a second electrically conductive upper surface 41.1 and a second electrically conductive lower surface 41.2.

[0076] The first layer 44 and the second layer 41 are arranged at a distance from each other, on either side of the second electrically conductive lower surface 41.2 and the first electrically conductive upper surface 44.1 which are in contact.

[0077] Thus, the first layer 44 and the second layer 41 form a stack.

[0078] Electrically conductive surfaces are coatings made of a metallic material, for example copper.

[0079] The first and second layers are made of a dielectric material, for example epoxy resin.

[0080] The propagation zone 48 corresponds to a zone of the waveguide in which the electromagnetic wave is confined during its propagation in the waveguide 42.

[0081] The waveguide 42 comprises a plurality of plated through holes 43 which extend along a vertical axis ZZ orthogonal to the XY plane, for electrically connecting the second electrically conductive lower surface 41.2 and the second electrically conductive upper surface 41.1 through the second layer 41. Each plated through hole thus forms a via between the second conductive upper surface 41.1 and the second conductive lower surface 41.2.

[0082] The vias are arranged along a propagation axis, in two distinct rows, at a distance from each other.

[0083] The distance between two successive vias of the same row is less than the smallest of the wavelengths of the electromagnetic waves intended to propagate in the waveguide, for example less than or equal to one fifth of the smallest of the wavelengths of the waves intended to propagate in the waveguide.

[0084] The propagation zone 48 is thus delimited, according to the thickness, by the second upper conductive surface 41.1, the second lower conductive surface 41.2, and according to the width, by the two rows of vias arranged on either side of a propagation axis.

[0085] The pattern formed by the vias defines the RF function performed by the microwave component.

[0086] Figure 6 illustrates an example of a waveguide propagation zone configured to perform the combiner / divider function. View (a) is a top view of the second conductive upper surface 41.1 of the microwave component. The plated holes are arranged to form a T-shaped propagation zone. More specifically, the vias are arranged to form a first propagation zone 48.1 that extends between port 1 and the combination zone 48.4 along a transverse propagation axis YY, a second propagation zone 48.2 that extends between port 2 and the combination zone 48.4 along a longitudinal propagation axis XX, and a third propagation zone 48.3 that extends between port 3 and the combination zone 48.4 along the longitudinal propagation axis XX.

[0087] The absorption zone 47 is defined in the support substrate and which corresponds to an area in which the electromagnetic wave is absorbed or attenuated during its propagation. The absorption zone is delimited, according to the thickness, by the first upper electrically conductive surface 44.1 and the first lower electrically conductive surface 44.2, according to the width, by two spaced lateral boundaries 46.

[0088] According to one embodiment, the spaced lateral boundaries 46 of the absorption zone are formed by a plurality of metallized through holes which extend along a vertical axis ZZ orthogonal to the XY plane, through the support substrate 44 to electrically connect the first upper electrically conductive surface 44.1 and the first lower electrically conductive surface 44.2.

[0089] The metallized holes 46 are arranged along a propagation axis, in two distinct rows, at a distance from each other.

[0090] The distance between two successive metallized holes in the same row is less than the smallest of the wavelengths of the electromagnetic waves intended to propagate in the support substrate. Each metal hole here has, for example, a cylindrical shape. According to a variant, it may have a rectangular shape. The metallized holes locally modify the boundary conditions in the substrate 44 which constrain the propagation of the wave in the support substrate 44.

[0091] The pattern of the absorption zone can be adapted so that the length of the absorption zone is sufficient to absorb the electromagnetic wave. In view (c) of Figure 6 which is a top view of the first conductive upper surface 44.1 of the microwave component, the pattern formed by the metallized holes defines a meander in which the electromagnetic wave will be absorbed or gradually attenuated during its propagation.

[0092] Referring to Figure 5, the feed element comprises a first slot 49.1 made in the second lower conductive surface 41.2 and a second slot 49.2 made in the first upper conductive surface 44.1, the two slots being aligned and arranged opposite the combination zone 48.4 in order to be able to collect at least a fraction of the electromagnetic wave coming from the electromagnetic waveguide.

[0093] Preferably, the dimension of the first slot 49.1 is substantially smaller than that of the second slot 49.2 or vice versa in order to ensure alignment between the first slot and the second slot to avoid the situation in which a misalignment between the two slots results in an obstruction of one of the two slots. The two slots are positioned opposite the entrance to the absorption zone 47, as shown in view (c) of Figure 6. The two slots have the function of sampling at least a fraction of the electromagnetic wave coming from the propagation zone 48 and to inject it into the absorption zone 47.

[0094] The operation of the combiner microwave component 40 of Figure 5 will now be described, with reference to Figures 7A-7D which show the magnitude of the electric field in the microwave component.

[0095] Figure 7A shows a normal operation of the microwave component. The signal is injected into port 1 of the combiner / divider component. The signal propagates in the first propagation zone to the central zone and then splits into two signals which propagate respectively in the second propagation zone to exit via port 2 and in the third propagation zone to exit via port 3.

[0096] Figure 7B shows the amplitude of the electric field in the microwave component operating in a situation in which a part of the signal entering port 2 is taken at the central area by the coupling element, namely the slots 49.1, 49.2 and injected into the absorption area made in the lower substrate layer. Thus, the leakage signal is strongly canceled at the central area and port 3 is thus isolated and protected.

[0097] Figure 7C shows the electric field amplitude in the microwave component operating in a situation where a portion of the signal entering port 3 is taken from the central area by the feed element and injected into the absorption area provided in the lower substrate layer. Thus, the leakage signal is strongly canceled at the central area and port 2 is thus isolated and protected.

[0098] Figure 7D shows a view of the electric field amplitude in the absorption region made in the lower substrate layer from the lower face of the microwave component. It can be seen that the field amplitude gradually decreases during the propagation of the wave in the absorption region until it is completely cancelled.

[0099] Figure 8 shows a variant of the embodiment of Figure 5. The microwave component of Figure 8 differs from that of Figure 5 in that the pattern formed by the vias allows a coupling function to be performed. The feed element further comprises an impedance matching element 55 positioned at the input of the absorption zone.

[0100] The microwave component 50 is here of the type with a guide integrated into the SIW substrate.

[0101] The component 50 comprises a waveguide 52 capable of guiding an electromagnetic wave along at least one propagation axis, a support substrate 54 made of dielectric material suitable for ensuring the mechanical rigidity of the component, a zone absorption element 57 extending into the support substrate for guiding the propagation of electromagnetic waves from the waveguide into the substrate to absorb wave energy or attenuate wave energy, and a feed element 59.1, 59.2, 55 positioned at the entrance to the absorption zone and configured to take at least a fraction of the electromagnetic wave from the propagation zone and to inject it into the absorption zone.

[0102] The support substrate comprises a first layer 54 of dielectric material that extends in an XY plane. The first layer 54 has a first electrically conductive upper surface 54.1 and a first electrically conductive lower surface 54.2.

[0103] The waveguide 52 comprises a second layer of dielectric material 51 in which a propagation zone 58 is defined. The second layer of dielectric material 51 extends in the XY plane. The second layer of dielectric material has a second electrically conductive upper surface 51.1 and a second electrically conductive lower surface 51.2.

[0104] The first layer 54 and the second layer 51 are arranged at a distance from each other, on either side of the second electrically conductive lower surface 51.2 and the first electrically conductive upper surface 54.1 which are in contact.

[0105] Thus, the first layer 54 and the second layer 51 form a stack.

[0106] The propagation zone 58 corresponds to a zone of the waveguide in which the electromagnetic wave is confined during its propagation in the waveguide 42.

[0107] The waveguide 52 comprises a plurality of plated through holes 53 which extend along a vertical axis ZZ orthogonal to the XY plane, for electrically connecting the second electrically conductive lower surface 51.2 and the second electrically conductive upper surface 51.1 through the second layer 51. Each plated through hole thus forms a via between the second conductive upper surface 51.1 and the second conductive lower surface 51.2.

[0108] The propagation zone 58 is thus delimited, according to the thickness, by the second upper conductive surface 51.1, the second lower conductive surface 51.2, and according to the width, by the two rows of vias arranged on either side of a propagation axis.

[0109] Figure 9 illustrates an example of a waveguide propagation zone configured to perform the coupler function. View (a) is a top view of the second conductive upper surface 51.1 of the microwave component. The component comprises a first propagation zone 58.1 which extends between port 1 and port 2 and a second propagation zone 58.2 which extends between port 4 and port 3. The two propagation zones are thus formed by three rows of substantially parallel vias. The central row comprises a central zone devoid of vias, making it possible to establish a coupling between the first and second propagation zones.

[0110] The absorption zone 57 is defined in the support substrate and corresponds to an area in which the electromagnetic wave is absorbed or attenuated during its propagation. The absorption zone is delimited, according to the thickness, by the first upper electrically conductive surface 54.1 and the first lower electrically conductive surface 54.2, according to the width, by two spaced lateral boundaries 56.

[0111] According to one embodiment, the spaced lateral boundaries 56 of the absorption zone are formed by a plurality of metallized through holes which extend along a vertical axis ZZ orthogonal to the XY plane, through the support substrate 54 to electrically connect the first upper electrically conductive surface 54.1 and the first lower electrically conductive surface 54.2.

[0112] The metallized holes 56 are arranged along a propagation axis, in two distinct rows, at a distance from each other.

[0113] In view (c) of Figure 9 which is a top view of the first conductive upper surface 54.1 of the microwave component, the metallized holes form a pattern “C” in which the electromagnetic wave will be absorbed or attenuated progressively during its propagation. The absorption zone can be of different shapes depending on the volume available in the support substrate.

[0114] The feed element comprises a first slot 59.1 made in the second lower conductive surface 51.2 and a second slot 59.2 made in the first upper conductive surface 54.1, the two slots being aligned and arranged opposite the port 4 in order to be able to take at least a fraction of the electromagnetic wave coming from the electromagnetic waveguide 52. In other words, the port 4 which is an unused port is connected to the absorption zone which is located in the support substrate 54.

[0115] The two slits have the function of collecting all the energy carried by the electromagnetic wave coming from the propagation zone 58 and injecting it into the absorption zone 57.

[0116] According to one embodiment, the power supply element further comprises an impedance matching element 55 which is in the form of a set of metallized steps made in the support substrate, at the entrance to the absorption zone. The slots and the metallized steps can be opposite.

[0117] The operation of the coupler microwave component 50 of Figure 8 will now be described, with reference to Figures 10A-10D which show the magnitude of the electric field in the microwave component.

[0118] Figure 10A shows a normal operation of the microwave component. The signal is injected into port 1 of the combiner / divider component. The signal propagates in the first propagation zone between port 1 and port 2 and in the second propagation zone between port 1 and port 3.

[0119] Figure 10B shows the electric field amplitude in the microwave component operating in a situation where a representative 50% portion of the signal entering port 3 is taken at port 4 by the feed element and injected into the absorption region provided in the lower substrate layer. Thus, the leakage signal is strongly canceled at the coupling region and port 2 is thus isolated and protected.

[0120] Figure 10C shows the electric field amplitude in the microwave component operating in a situation where a representative 50% portion of the signal entering port 2 is taken at port 4 by the feed element and injected into the absorption region provided in the lower substrate layer. Thus, the leakage signal is strongly canceled at the coupling region and port 3 is thus isolated and protected.

[0121] Figure 10D shows a view of the electric field amplitude in the C-shaped absorption region formed in the lower substrate layer from the lower surface of the microwave component. It can be seen that the field amplitude gradually decreases during wave propagation in the absorption region until it is completely cancelled.

[0122] Figure 11 represents a second embodiment of a component 60 according to the invention.

[0123] The microwave component 60 may be, for example, a filter, an antenna, a coupler, a combiner, a divider or an isolator.

[0124] The microwave component 60 is of the hollow substrate-integrated waveguide or hollow SIW type.

[0125] The component 60 comprises a waveguide 62 capable of guiding an electromagnetic wave along at least one propagation axis, a support substrate 64 in dielectric material suitable for ensuring the mechanical rigidity of the component, an absorption zone 67 extending into the support substrate for guiding the propagation of electromagnetic waves coming from the waveguide into the substrate in order to absorb the energy of the waves or to attenuate the energy of the waves, and a feed element 69 positioned at the entrance to the absorption zone and configured to take at least a portion of the electromagnetic wave coming from the propagation zone and to inject it into the absorption zone.

[0126] The support substrate comprises a first layer 64 of dielectric material that extends in an XY plane. The first layer 64 has a first electrically conductive upper surface 64.1 and a first electrically conductive lower surface 64.2.

[0127] The waveguide 62 comprises a second layer of dielectric material 61. The second layer of dielectric material 61 extends in the XY plane. The second layer of dielectric material has a second electrically conductive upper surface 61.1 and a second electrically conductive lower surface 61.2.

[0128] The first layer 64 and the second layer 61 are arranged at a distance from each other, on either side of the second electrically conductive lower surface 61.2 and the first electrically conductive upper surface 64.1 which are in contact.

[0129] Thus, the first layer 64 and the second layer 61 form a stack.

[0130] The propagation zone 68 corresponds to a zone of the waveguide in which the electromagnetic wave is confined during its propagation in the waveguide 62.

[0131] The waveguide 62 comprises an internal cavity 63 made in the support substrate. The side walls 68.1, 68.2 and the bottom wall 68.3 of said cavity are metallized. The internal cavity is delimited by the second lower electrically conductive surface 61.2 and the metallized walls of the cavity.

[0132] The propagation zone 68 is thus delimited, according to the thickness, by the second conductive lower surface 61.2 and the metallized lower wall of the cavity, according to the width, by the two metallized side walls of the cavity.

[0133] The internal cavity 63 may be filled with a fluid having a dielectric constant that may be different from the dielectric constant of the substrate. The fluid is, for example, air or vacuum. Alternatively, in the case where the internal cavity 63 defines a sealed closed volume, it is filled with nitrogen or is empty of fluid.

[0134] The absorption zone 67 is defined in the support substrate and corresponds to an area in which the electromagnetic wave is absorbed or attenuated during its propagation. The absorption zone is delimited, according to the thickness, by the first upper electrically conductive surface 64.1 and the first lower electrically conductive surface 64.2, according to the width, by two spaced lateral boundaries 66.

[0135] According to one embodiment, the spaced lateral boundaries 66 of the absorption zone are formed by a plurality of metallized through holes which extend along a vertical axis ZZ orthogonal to the XY plane, through the support substrate 64 to electrically connect the first upper electrically conductive surface 64.1 and the first lower electrically conductive surface 64.2. The metallized holes 66 are arranged along a propagation axis, in two distinct rows, at a distance from each other.

[0136] According to the example illustrated in Figure 11, the feed element here comprises a slot 69 made in the lower wall 68.3 of the cavity 68 to take a portion of the electromagnetic wave coming from the waveguide 62 and inject it into the absorption zone 67. According to another variant, the slot 69 can be made in one of the side walls 68.1, 68.2 of the cavity 68. The number of slots is not limiting.

[0137] Figure 12 illustrates an exemplary embodiment of Figure 11.

[0138] The microwave component 80 may be a combiner or divider.

[0139] The microwave component 80 is of the hollow substrate-integrated waveguide or hollow SIW type.

[0140] The component 80 comprises a waveguide 82 capable of guiding an electromagnetic wave along at least one propagation axis and a support substrate made of dielectric material suitable for ensuring the mechanical rigidity of the component, an absorption zone 87 extending in the support substrate to guide the propagation of electromagnetic waves coming from the waveguide in the substrate in order to absorb the energy of the waves or to attenuate the energy of the waves, and a feed element 89 positioned at the entrance to the absorption zone and configured to take at least a fraction of the electromagnetic wave coming from the propagation zone and to inject it into the absorption zone.

[0141] The waveguide 82 here comprises an internal cavity 83 in the shape of a “Y”. It comprises a first propagation zone 88.1 which extends between the port 1 and a central zone 88.4, a second propagation zone 88.2 which extends between the central zone 88.4 and the port 2 and a third propagation zone 88.3 which extends between the central zone 88.4 and the port 3.

[0142] The absorption zone 87 is defined in the support substrate and which corresponds to an area in which the electromagnetic wave is absorbed or attenuated during its propagation.

[0143] Figure 12 shows a top view of the cavity located under the first conductive upper surface of the microwave component, showing a view of the “Y” shaped cavity and the support substrate 84. The absorption zone 87 comprises a plurality of plated holes 86 forming a meander in which the electromagnetic wave will be absorbed or attenuated progressively during its propagation. The absorption zone forms a meander to reduce the dimensions. It can be noted that here, the absorption zone is wider than the previous examples in order to take into account the signal power which is greater.

[0144] The feed element comprises a slot 89 made in the lower wall of the cavity 83 to take a fraction of the electromagnetic wave coming from the waveguide and inject it into the absorption zone. The slot 89 is here located at the central junction zone 88.4 of the “Y” shaped waveguide.

[0145] The operation of the microwave component 80 of Figure 12 will now be described, with reference to Figures 13A-13C which represents the amplitude of the electric field in the microwave component.

[0146] Figure 13A shows the electric field amplitude in the microwave component of Figure 12 operating in a normal usage configuration. The signal is injected into port 1 and outputs at ports 2 and 3.

[0147] Figure 13B shows the amplitude of the electric field in the microwave component operating in a situation in which part of the signal energy from port 3 is taken at slot 89 and injected into the absorption zone made in the lower substrate layer, port 2 is thus isolated and protected.

[0148] Figure 13C shows the amplitude of the electric field in the microwave component operating in a situation in which part of the signal energy from port 2 is taken at slot 89 and injected into the absorption zone made in the lower substrate layer, port 3 is thus isolated and protected.

[0149] Figure 14 represents a variant of the embodiment of Figure 12.

[0150] The microwave component 90 may be a combiner or a divider.

[0151] The microwave component 90 is of the hollow substrate-integrated waveguide or hollow SIW type.

[0152] The component 90 comprises a waveguide 92 capable of guiding an electromagnetic wave along at least one propagation axis and a support substrate made of dielectric material suitable for ensuring the mechanical rigidity of the component, an absorption zone 97 extending in the support substrate to guide the propagation of electromagnetic waves coming from the waveguide in the substrate in order to absorb the energy of the waves or to attenuate the energy of the waves, and a feed element 99 positioned at the entrance to the absorption zone and configured to take at least a fraction of the electromagnetic wave coming from the propagation zone and to inject it into the absorption zone.

[0153] The waveguide 92 comprises a metallized internal cavity 93 in the shape of a “Y”. It comprises a first propagation zone 98.1 which extends between the port 1 and a central zone 98.4, a second propagation zone 98.2 which extends between the central zone 98.4 and the port 2 and a third propagation zone 98.3 which extends between the central zone 98.4 and the port 3.

[0154] The absorption zone 97 is defined in the support substrate and which corresponds to an area in which the electromagnetic wave is absorbed or attenuated during its propagation.

[0155] Figure 14 shows a top view of the cavity 93 located under the first upper conductive surface of the microwave component, showing a view of the Y-shaped cavity 93 integrated in the support substrate 94. The absorption zone 97 is defined by the metallized holes 96 which here form a ring in which the electromagnetic wave will be absorbed or gradually attenuated during its propagation. In the example shown in Figure 14, the ring is centered substantially on the central junction zone 98.4 of the Y-shaped waveguide. The ring shape advantageously makes it possible to reduce the surface area of ​​the absorption zone by a factor of two (2) compared to an S-shape of Figure 14.

[0156] The feed element comprises a slot 99 made in the lower bottom wall of the cavity 93 to take a fraction of the electromagnetic wave coming from the waveguide and inject it into the absorption zone.

[0157] The operation of the microwave component 90 of Figure 14 will now be described, with reference to Figures 15A-15C which represents the amplitude of the electric field in the microwave component.

[0158] Figure 15A shows the electric field amplitude in the microwave component of Figure 14 operating in a normal splitter configuration. The signal is injected into port 1 and output at ports 2 and 3.

[0159] Figure 15B shows the amplitude of the electric field in the microwave component operating in a situation in which the signal is coming from port 3 and a part of the signal energy coming from port 3 is taken at the level of the slot 99 and injected into the absorption zone made in the lower substrate layer, the port 2 is thus isolated and protected.

[0160] Figure 15C shows the amplitude of the electric field in the microwave component operating in a situation in which the signal is coming from port 2 and a part of the signal energy coming from port 2 is taken at the level of the slot 99 and injected into the absorption zone made in the lower substrate layer, the port 3 is thus isolated and protected.

[0161] Figures 16A and 16B show another example embodiment of a hollow SIW electronic component whose waveguide 72 comprises a channel integrated in the support substrate 74 of the component. Figure 16A shows only a view from above of the channel 72 located under the first conductive upper surface of the support substrate. The absorption zone 76 is defined by the metallized holes and forms a “U” pattern in which the electromagnetic wave will be absorbed or attenuated progressively during its propagation.

[0162] In this embodiment, the feed element 79 comprises a non-metallized hollow zone formed by the extension of one end of the channel which opens into the support substrate 74. This hollow zone thus comprises an end interfacing with the end of the channel of the guide and an end in the form of a point which penetrates into the absorption zone 76. In order to achieve impedance matching between the cavity 73 of the channel which contains air and the absorption zone 76 made of dielectric material, a set of metallized steps 78 is produced at the end of the channel. The hollow zone or the extension of the end of the channel is not metallized and can take different geometric shapes. The boundary between the channel and the entrance to the absorption zone is marked by a row of vias 75.

[0163] In the example shown here, each of the boundaries to define the absorption zone is formed by two rows of plated holes instead of a single row of plated holes in order to ensure better electromagnetic shielding of the absorption zone.

[0164] The operation of the termination load microwave component of Figure 16A will now be described, with reference to Figure 17 which shows the magnitude of the electric field in the microwave component.

[0165] Figure 17 shows a view of the electric field amplitude in the "U" shaped absorption region provided in the support substrate layer, under the first conductive upper surface of the microwave component.

[0166] The signal from port 1 is injected into the absorption zone 77 via the feed element 79. It therefore passes through a transition between air and the material of the support substrate. It can be seen that the amplitude of the field gradually decreases during the propagation of the wave in the absorption zone until it is completely cancelled.

[0167] The embodiments described above can be combined in any technically possible combination.

[0168] Due to the features described above, the microwave component of the present disclosure is simple and can integrate a load to absorb an electromagnetic wave from the waveguide while being compact and low cost.

Claims

Claims

1. Microwave component (40), said component comprising: - at least one waveguide (42) comprising a propagation zone (48) of an electromagnetic wave, said propagation zone extending along a propagation axis; - a support substrate (44) made of dielectric material suitable for ensuring the mechanical rigidity of said component; - said support substrate comprising a first layer made of dielectric material having a first upper electrically conductive surface (44.1) and a first lower electrically conductive surface (44.2) respectively covering an upper face and a lower face of said support substrate; - at least one absorption zone (47) extending into the support substrate for guiding the propagation of electromagnetic waves from said waveguide into the substrate to absorb wave energy or attenuate wave energy, said absorption zone being delimited by the first upper electrically conductive surface (44.1), the first lower electrically conductive surface (44.2) and two spaced-apart lateral boundaries (46) suitable for preventing the passage of an electromagnetic wave; - a feed element (49.1, 49.2) positioned at the entrance to said absorption zone (47) and configured to take at least a portion of the electromagnetic wave coming from said propagation zone (48) of said at least one waveguide and to inject it into said absorption zone (47).

2. A component according to claim 1, wherein said lateral boundaries of the absorption zone are formed by a plurality of metallized through holes (46, 56, 66, 86, 96) extending through the support substrate (44, 54, 64) for electrically connecting the first upper electrically conductive surface and the first lower electrically conductive surface.

3. A component according to one of claims 1 to 2, wherein the plurality of metallized through holes (46, 56, 66, 86, 96) defines a pattern having the shape of a meander.

4. A component according to one of claims 1 to 3, wherein the plurality of metallized through holes (46, 56, 66, 86, 96) defines a pattern having the shape of a ring.

5. Component according to one of claims 1 to 4, in which the first layer made of dielectric material (44) has a thickness of between 0.2 mm and 10 mm, preferably between 0.5 mm and 6 mm.

6. Component according to one of claims 1 to 5, wherein said at least one waveguide comprises a second layer of dielectric material (41, 51) having a second electrically conductive upper surface (41.1, 51.1) and a second electrically conductive lower surface (41.2, 51.2), said second electrically conductive lower surface (41.2, 51.2) being in electrical contact with said first electrically conductive upper surface (44.1, 54.1) of said support substrate, the propagation zone (48, 58) being defined in said second layer of dielectric material (41, 51) and delimited by the second electrically conductive upper surface (41.1, 51.1), the second electrically conductive lower surface (41.2, 51.2) and by a plurality of metallized through holes (43, 53) extending through said second layer of dielectric material.

7. A component according to claim 6, wherein said feed element comprises a first slot (49.1, 59.1) made in the second lower conductive surface (41.2, 51.2) and a second slot (49.2, 59.1) made in the first upper conductive surface (44.1, 54.1), the two slots being aligned and arranged opposite the entrance to the absorption zone.

8. A component according to claim 7, wherein the feed element (55) comprises a set of metallized steps formed in the support substrate, at the interface between the support substrate (54) and the first conductive lower surface (54.2).

9. Component according to one of claims 1 to 5, wherein said at least one waveguide comprises a second layer of dielectric material (61) having a second electrically conductive upper surface (61.1) and a second electrically conductive lower surface (61.2), said second electrically conductive lower surface (61.2) being in electrical contact with said first electrically conductive upper surface (64.1) of said support substrate, said propagation zone (68) comprises an internal cavity (63) made in the support substrate, the side walls (68.1, 68.2) and the lower wall (68.3) of said cavity being metallized, the propagation zone being delimited by the second electrically conductive lower surface (61.2) and the metallized walls of the cavity (68.1, 68.2, 68.3).

10. A component according to claim 9, wherein the feed element comprises a hollow area (79) formed in the support substrate (74), said hollow area being formed from an extension of one end of the internal cavity (73) of the waveguide (72).

11. A component according to claim 10, wherein the hollow area comprises a first end forming an interface with the end of the cavity and a second end in the form of a tip (79) penetrated into the absorption area (77) of the substrate.

12. A component according to claim 11, wherein the end of the cavity located at the interface with the first end of the hollow area comprises a set of metallized steps (78) for providing impedance matching between the cavity and the absorption area.

13. Component according to claim 9, wherein said feed element comprises at least one slot (69, 89, 99) made in one of the walls of the internal cavity (83, 93) of the waveguide.

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