Microwave component with at least one load integrated into the support substrate

Abstract

A 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) of dielectric material adapted to ensure 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 and a lower face of said support substrate; - at least one absorption zone (47) extending into the support substrate to guide the propagation of electromagnetic waves from said waveguide into the substrate in order to absorb or attenuate the energy of the waves, 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 lateral boundaries (46) designed to prevent the passage of an electromagnetic wave; - a feed element (49.1, 49.2) positioned at the entrance of said absorption zone (47) and configured to take at least a portion of the electromagnetic wave from said propagation zone (48) of said at least one waveguide and inject it into said absorption zone (47). Abstract figure: Figure 5.

Description

Title of the invention: 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] In order to reduce manufacturing costs and enable mass production, microwave components are produced using planar technology.

[0004] [Fig. 1] shows an exemplary 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] [Fig.2] shows another example of the embodiment of a co-transmission line planar 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] [Fig.3] shows an illustration of an example of the structure of a waveguide SIW 20 configured to guide an electromagnetic wave along a propagation axis XX. It comprises a central layer 21 made of a material di electrical 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, for example, of copper. The dielectric layer is made, for example, of an epoxy resin.

[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 consequently 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 a low manufacturing cost and is easily integrated into a system based on printed circuits. The components generally have a very light structure, while allowing a high integration density in the 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 still maintaining low cost and high integration, an 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] [Fig. 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 layer conductive 35. A longitudinal cavity 38 is made 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 illustrated in Figures 1 to 4 are not entirely satisfactory. Indeed, when termination loads are required in a radiofrequency circuit design, they are added externally or into the structure manually. The structure must then be shielded manually. 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 linked to radiofrequency leaks 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 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] Consequently, 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 causing additional manufacturing costs, while maintaining the performance required for these components. Summary

[0017] The present 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 suitable for preventing 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 one another or in combination with one another.

[0020] The lateral boundaries of the absorption zone 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 upper surface electrically conductive 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 through-metallized holes extending through said second layer of dielectric material.

[0025] According to an exemplary embodiment, said feed 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 supply 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 zone 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 zone 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 characteristics, details and advantages will appear on reading the detailed description below, and on analyzing the attached drawings, in which: Fig. 1

[0033] [Fig-1] [Fig.l] is a sectional view of a microwave component comprising a micro-ribbon transmission line, in a plane orthogonal to the propagation axis XX; Fig. 2

[0034] [Fig.2] [Fig.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] [Fig.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] [Fig.4] is a sectional view of a microwave component of the type AFSIW, in a plane orthogonal to the propagation axis XX; Fig.5

[0038] [Fig.5] [Fig.5] is a sectional view of a combiner microwave component / isolated power divider according to an embodiment of the invention, in a plane orthogonal to the propagation axis XX; Fig.6

[0039] [Fig.6] [Fig.6] shows respectively: (a) a top view of the second upper conductive top surface of the microwave component of [Fig.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] [Fig.7A] represents the magnitude of the electric field in the microwave component operating in a normal use configuration, with the signal applied to port 1 and the signal outputting at ports 2 and 3; Fig.7B

[0041] [Fig.7B] [Fig.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] [Fig.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] [Fig.7D] represents a view of the amplitude of the electric field in the absorption zone realized in the lower substrate layer from the lower face of the microwave component; Fig.8

[0044] [Fig.8] [Fig.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] [Fig.9] shows respectively: (a) a top view from the surface upper surface of the upper conductive layer of the upper dielectric layer of the coupler of [Fig.8], (b) a top view from the upper surface of the lower conductive layer of the upper dielectric layer of the coupler of [Fig.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 [Fig.8]; Fig. 10A

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

[0047] [Fig.lOB] [Fig.lOB] 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 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] [Fig.10C] 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 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.lOD] [Fig.lOD] represents a view of the amplitude of the electric field in the absorption zone realized in the lower substrate layer from the lower face of the microwave component; Fig. ll

[0050] [Fig. 11] [Fig. 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] [Fig. 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.l3A] [Fig.l3A] represents the magnitude of the electric field in the microwave component of [Fig. 12] operating in a normal use configuration, with the signal applied to port 1 and the signal exiting at ports 2 and 3; Fig.l3B

[0053] [Fig.l3B] [Fig.l3B] represents the amplitude of the electric field in the microwave component operating in a situation in which a part of the signal energy coming from port 3 is taken at the slot and injected into the absorption zone made in the lower substrate layer, port 2 is thus protected; Fig.l3C

[0054] [Fig.l3C] [Fig.l3C] represents the amplitude of the electric field in the microwave component operating in a situation in which a part of the signal energy coming from port 2 is taken at the junction and injected into the absorption zone made in the lower substrate layer, port 3 is thus protected; Fig. 14

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

[0056] [Fig.l5A] [Fig.l5A] represents the magnitude of the electric field in the microwave component of [Fig. 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.l5B] [Fig.l5B] represents the amplitude of the electric field in the microwave component operating in a situation in which the signal comes from port 3 and a part of the signal energy coming from port 3 is taken at the central area via the slot and injected into the absorption area made in the support substrate layer, port 2 is thus isolated and protected; Fig. 15C

[0058] [Fig.l5C] [Fig.l5C] represents the amplitude of the electric field in the microwave component operating in a situation in which the signal comes from port 2 and a part of the signal energy coming from port 2 is taken at the central area via the slot and injected into the absorption area made in the lower substrate layer, port 3 is thus isolated and protected. Fig. 16A

[0059] [Fig.16A] [Fig.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 dielectric support substrate of the component; Fig. 16B

[0060] [Fig.16B] [Fig.16B] represents an enlarged top view of the impedance matching and feeding zone between the cavity and the absorption zone of [Fig.16A]; Fig. 17

[0061] [Fig. 17] [Fig. 17] is a representation of the electric field amplitude in the feed element and absorption region of [Fig.16A] when injecting a signal from a 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, signals may reflect back into the system, which can introduce distortion and other undesirable effects. Loads are used in couplers, hybrids, isolators, test equipment, and in systems where a port must be terminated. There are three main types of RF terminations: coaxial, waveguide, and chip.In the present disclosure, the fillers are used to terminate the waveguide ports.

[0065] In the context 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 electromagnetic radiation 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 in the substrate of support, it is no longer necessary to manually add the RF load to the outside or inside the component structure and to manually shield the structure. Such a component can be adapted to mass production and helps limit production costs. 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 limiting the size of the structure. The absence of interfaces also helps limit the risks of loss of efficiency and electromagnetic compatibility linked to radiofrequency leakage.

[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 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 which 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 an 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 metallized through holes 43 which extend along a vertical axis ZZ orthogonal to the XY plane, to electrically connect the second electrically conductive lower surface 41.2 and the second electrically conductive upper surface 41.1 through the second layer 4L. Each metallized 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] [Fig.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 which extends between port 1 and the combination zone 48.4 along a transverse propagation axis YY, a second propagation zone 48.2 which extends between port 2 and the combination zone 48.4 along a longitudinal propagation axis XX, and a third propagation zone 48.3 which 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 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 electrically conductive surface lower trically conductive 44.2, depending on the width, by two spaced lateral borders 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 of 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 has here for example a cylindrical shape. According to a variant, it can 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 [Fig.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] With reference to [Fig.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 take 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 [Fig.6]. The two slots have the function of taking at least a fraction of the electromagnetic wave coming from the propagation zone 48 and injecting it into the absorption zone 47.

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

[0095] [Fig.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 separates 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] [Fig.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] [Fig.7C] shows the amplitude of the electric field in the microwave component operating in a situation in which a part of the signal entering port 3 is taken at the central area by the feed element 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 2 is thus isolated and protected.

[0098] [Fig.7D] shows a view of the amplitude of the electric field in the absorption zone made in the lower substrate layer from the lower face of the microwave component. 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.

[0099] [Fig. 8] represents a variant of the embodiment of [Fig. 5]. The microwave component of [Fig. 8] differs from that of [Fig. 5] in that the pattern formed by the vias makes it possible to perform a coupling function. 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 a dielectric material suitable for ensuring the mechanical rigidity of the component, an absorption zone 57 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 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 coming from the zone propagation and to inject it into the absorption zone.

[0102] The support substrate comprises a first layer 54 of dielectric material which 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 is confined the electromagnetic wave 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] [Fig.9] illustrates an example of a propagation zone of the waveguide configured to perform the coupler function. View (a) is a top view of the second upper conductive 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 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 54.1 and the first lower electrically conductive surface 54.2, along the width, by two spaced lateral boundaries 56.

[0111] According to one embodiment, the spaced lateral boundaries 56 of the zone absorption 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 [Fig.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 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 here all of 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 may be opposite each other.

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

[0118] [Fig. 10A] shows 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] [Fig. 10B] represents the amplitude of the electric field in the micro component waves operating in a situation in which a representative portion of 50% of the signal entering port 3 is taken at port 4 by the feed element and injected into the absorption zone made in the lower substrate layer. Thus, the leakage signal is strongly canceled at the coupling zone and port 2 is thus isolated and protected.

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

[0121] [Fig.10D] shows a view of the amplitude of the electric field in the "C"-shaped absorption zone made in the lower substrate layer from the lower face of the microwave component. 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.

[0122] [Fig. 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 waveguide type integrated into the substrate or hollow SIW.

[0125] The component 60 comprises a waveguide 62 capable of guiding an electromagnetic wave along at least one propagation axis, a support substrate 64 made of a dielectric material suitable for ensuring the mechanical rigidity of the component, an absorption zone 67 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 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 which 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 dielectric material layer 61. The second dielectric material layer 61 extends in the XY plane. The second dielectric material layer has a second upper electrical surface electrically conductive 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 is confined the electromagnetic wave 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 [Fig. 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] [Fig. 12] illustrates an exemplary embodiment of [Fig. 11].

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

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

[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] [Fig. 12] shows a view from above of the cavity located under the first upper conductive 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 metallized 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 [Fig. 12] will now be described, with reference to Figures 13A-13C which represents the amplitude of the electric field in the microwave component.

[0146] [Fig.l3A] represents the amplitude of the electric field in the microwave component of [Fig. 12] operating in a normal use configuration. The signal is injected into port 1 and output at ports 2 and 3.

[0147] [Fig.l3B] represents the amplitude of the electric field in the microwave component operating in a situation in which a part of the signal energy coming from port 3 is taken at the level of the slot 89 and injected into the absorption zone made in the lower substrate layer, port 2 is thus isolated and protected.

[0148] [Fig.l3C] represents the amplitude of the electric field in the microwave component operating in a situation in which a part of the signal energy coming from port 2 is taken at the level of the slot 89 and injected into the absorption zone made in the lower substrate layer, port 3 is thus isolated and protected.

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

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

[0151] The microwave component 90 is of the type with a hollow waveguide integrated into the substrate or Hollow SIW.

[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] [Fig. 14] shows a view from above 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 attenuated progressively during its propagation. In the example shown in [Fig. 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 [Fig. 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 [Fig. 14] will now be described, with reference to Figures 15A-15C which represents the amplitude of the electric field in the microwave component.

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

[0159] [Fig.l5B] represents the amplitude of the electric field in the microwave component operating in a situation in which the signal comes from port 3 and a part of the energy of the signal 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, port 2 is thus isolated and protected.

[0160] [Fig.15C] represents the amplitude of the electric field in the microwave component operating in a situation in which the signal comes from port 2 and a part of the energy of the signal 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, 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. [Fig. 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 in interface 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 geometries. metrics. 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 for defining the absorption zone is formed by two rows of metallized holes instead of a single row of metallized holes in order to ensure better electromagnetic shielding of the absorption zone.

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

[0165] [Fig. 17] shows a view of the electric field amplitude in the "U" shaped absorption zone 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 the 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] Thanks to the characteristics described above, the microwave component of the present disclosure is simple and allows the integration of a load to absorb an electromagnetic wave coming 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 in the support substrate for guiding the propagation of electromagnetic waves coming from said waveguide in the substrate in order to absorb the energy of the waves or to attenuate the energy of the waves, 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 lateral boundaries (46) capable of preventing the passage of an electromagnetic wave; - a feed element (49.1, 49.2) positioned at the entrance of 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 in 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 zone comprises a set of metallized steps (78) for providing impedance matching between the cavity and the absorption zone.

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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