Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
  • H01P5/00—Coupling devices of the waveguide type
  • H01P5/02—Coupling devices of the waveguide type with invariable factor of coupling
  • H01P5/022—Transitions between lines of the same kind and shape, but with different dimensions
  • H01P5/024—Transitions between lines of the same kind and shape, but with different dimensions between hollow waveguides
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
  • H01P3/00—Waveguides; Transmission lines of the waveguide type
  • H01P3/16—Dielectric waveguides, i.e. without a longitudinal conductor
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
  • H01P5/00—Coupling devices of the waveguide type
  • H01P5/02—Coupling devices of the waveguide type with invariable factor of coupling
  • H01P5/022—Transitions between lines of the same kind and shape, but with different dimensions

Definitions

• the invention relates to a multilayer waveguide, that is to say a waveguide comprising a plurality of layers -in particular at least a plurality of layers formed of a dielectric material, called substrate-, superimposed on each other , possibly with intermediate dielectric layers of assembly, the different layers thus superimposed being etched so as to have guide channels in which an electromagnetic wave to guide propagates.
• the invention relates to a multilayer waveguide comprising a device for transition between two guide channels.
• multilayer waveguides Various structures of multilayer waveguides are known.
• the various layers may in particular be formed of printed circuit boards held together by assembly devices such as adhesive films (interlayers assembly) or screws.
• assembly devices such as adhesive films (interlayers assembly) or screws.
• Such multilayer waveguides can be used in particular for producing antennas.
• an interlayer dielectric layer each have an opening, the two openings of the two coupled guide channels being opposite one another and making it possible to transmit an electromagnetic wave through said intermediate dielectric layer and between these two coupled guide channels.
• APRIL 2012 discloses a waveguide comprising two printed circuit boards (PCBs) superposed by means of an adhesive film, each of the printed circuit boards having a network of coupling slots and channels formed of parallel rows of metal vias formed in the thickness of the plates.
• the number of superimposed layers of a multilayer waveguide formed by etching and stacking of printed circuit boards is limited, in practice from 10 to 20 layers depending on the technologies used.
• the electromagnetic waves guided in these known multilayer waveguides suffer energy losses during their transmission between two coupled guide channels, resulting in particular from a poor electrical contact, or even the absence of electrical contact between the channels. coupled guide.
• the poor contact between the coupled guide channels causes reflection of the electromagnetic waves and can also be the cause of parasitic radiation and energy losses, these disadvantages being amplified in the case of a misalignment guide channels coupled during the manufacture of the multilayer waveguide.
• US 2015/0303541 discloses a connection between a first waveguide of a first printed circuit board and a second waveguide of a second printed circuit board.
• the two waveguides are made of vias.
• the first waveguide has an opening on one face of the first plate facing an opening of the second waveguide on a face of the second plate.
• the connection comprises an insulating film disposed between the two printed circuit boards.
• a metal layer is disposed on the entire face of each plate having the opening of the waveguide on each side of the insulating film. The insulating film improves the transmission of electromagnetic waves.
• the insulating film consists of a deformable material under the effect of a pressure so that the insulating film has a shape that adapts to the defects of the plates and to avoid a presence of vacuum between these two plates so to improve the connection between the first waveguide and the second waveguide.
• the invention aims to overcome these disadvantages.
• the invention therefore aims at providing a multilayer waveguide for ensuring optimal transmission of the power of an electromagnetic wave guided between two layers of this multilayer waveguide.
• the invention therefore aims at providing such a multilayer waveguide in which the transmission losses of electromagnetic energy between coupled guide channels is minimized.
• the invention also aims at providing such a multilayer waveguide structure simple and inexpensive.
• the invention also aims at providing such a multilayer waveguide that is tolerant to manufacturing defects.
• the invention also aims to provide such a multilayer waveguide comprising a transition device between layers of this multilayer waveguide to increase the number of layers of this multilayer waveguide.
• the invention relates to a multilayer electromagnetic waveguide comprising several superposed layers forming channels for guiding an electromagnetic wave, and at least one transition device comprising at least one dielectric layer inserted between two guide channels, said coupled guide channels extending in a direction of transmission of an electromagnetic wave between said guide channels coupled via the transition device, characterized in that
• each transition device comprises at least one adaptation channel extending from the coupled guide channels, in a longitudinal direction secant to the direction of transmission,
• each adaptation channel is delimited by at least two electrically conductive walls, called adaptation walls, spaced from one another by said intermediate dielectric layer of said transition device, each adaptation wall extending according to the longitudinal direction along said intermediate dielectric layer from one end, said coupling end, of a coupled guide channel, and at least one adaptation wall extending in the longitudinal direction over a length chosen to obtain an impedance, said input impedance, at least substantially zero between the adaptation walls of this adaptation channel at the coupling ends of the coupled guide channels to optimize the transmission of an electromagnetic wave between the two channels of coupled guidance.
• the coupled guide channels extend along said transmission direction at the transition device.
• the coupled guide channels extend along the same axis oriented along said transmission direction.
• the coupled guide channels extend in said transmission direction but extend along a secant axis to said transmission direction.
• two coupled guide channels extend perpendicularly with respect to each other.
• each adaptation channel of a waveguide depends in particular on the characteristics of the electromagnetic wave to be transmitted and the characteristics of said intermediate dielectric layer.
• fringe field phenomena and radiation effects occur at the ends of each matching channel opposite to the guide channels and may be represented by a finite load and non-zero, called terminal load, equivalent to a resistor in parallel with a capacitor at this end of the adaptation channel.
• the length of at least one adaptation wall of each adaptation channel is chosen so as to minimize the insertion losses of the transition device. More particularly, the shorter adaptation wall of each adaptation channel is the one whose length must be adapted.
• the input impedance of an adaptation channel is the impedance of the terminal load brought back to the input of the adaptation channel.
• the value of the impedance of the terminal load generally depends on the thickness and permittivity of the interlayer dielectric layer and the permittivity of the superimposed layers forming guide channels.
• each adaptation channel is adjusted so as to obtain an impedance at least substantially zero, ideally zero
• the adaptation length of each adaptation channel can be chosen between ⁇ , ⁇ and 0.5 ⁇ , where ⁇ is the electromagnetic wavelength propagating in this adaptation channel.
• the length of each adaptation channel is generally less than the dimensions of the superimposed layers of the waveguide according to the invention.
• the length of each matching channel is less than the length of the intermediate dielectric layer.
• a transition device of a multilayer waveguide according to the invention makes it possible to minimize the transmission energy losses induced by the absence of electrical contact between two coupled guide channels.
• a device for transitioning a waveguide according to the invention also makes it possible to minimize the reflection of the wave.
• the minimization of the transmission energy losses of an electromagnetic wave is obtained over a wide frequency band (at least 30% of the central transmission frequency of the electromagnetic wave).
• the transition device according to the invention makes it possible to obtain transmission of an electromagnetic wave between two coupled guide channels similar to a transmission that can be obtained between guide channels that would be in electrical contact.
• the transition device thus makes it possible to improve the transmission of electromagnetic waves between two coupled guide channels.
• Improving the transmission of an electromagnetic wave between two coupled guide channels makes it possible to considerably increase the number of guide channels and layers of the multilayer waveguide according to the invention, and thus to facilitate the design of such multilayer waveguides and antennas comprising such multilayer waveguides.
• the transition device has the advantage of having a simple structure to manufacture and inexpensive.
• a device for transitioning a waveguide according to the invention is tolerant of manufacturing defects, an offset in the alignment of the coupled guide channels, and therefore of their walls. adaptation, resulting in very little energy loss compared to perfect alignment.
• the coupled guide channels extend in two different superposed layers of the multilayer electromagnetic waveguide.
• the intermediate dielectric layer extends between two superimposed layers of the multilayer electromagnetic waveguide, no electrically conductive element allowing electrical connection between these two superimposed layers being present between them.
• Said superimposed layers are thus electrically insulated from each other.
• the longitudinal direction of each adaptation channel is secant with the direction of transmission, that is to say in particular that it is not parallel to the latter.
• the angle formed between this longitudinal direction of an adaptation channel and the transmission direction may be arbitrary, but is preferably greater than 45 °, in particular greater than 60 °, more particularly between 80 ° and 90 °, values included. .
• the longitudinal direction of each adaptation channel is orthogonal to the direction of transmission.
• the adaptation walls of each adaptation channel are orthogonal to the guiding walls of the guide channels.
• At least one transition device comprises a single matching channel extending on one side only from the coupled guide channels in a longitudinal direction. secante to the direction of transmission.
• At least one transition device comprises at least two matching channels extending opposite each other from the coupled guide channels, each adaptation channel extending according to a longitudinal direction secant to the direction of transmission.
• At least one transition device comprises at least four adaptation channels extending in pairs opposite each other from the coupled guide channels, distributed at 90 ° around the guide channels. coupled, each adaptation channel extending in a longitudinal direction secant to the direction of transmission.
• a waveguide according to the invention comprises several superimposed layers for forming channels for guiding an electromagnetic wave.
• a waveguide according to the invention consists of at least one-especially a single plurality of stacked layers superimposed on each other and fixed to each other in pairs. At least two layers comprise at least one light, the different lights formed through the different layers being arranged to form guide channels within the waveguide. So, an electromagnetic wave can thus be guided in the different lights of each layer of the multilayer waveguide.
• a waveguide according to the invention comprises at least one transition device between two coupled guide channels extending respectively through the thickness of two superimposed layers via an intermediate dielectric layer. The faces of the adjacent layers define a plane, called the main plane, the thickness direction of the different layers being orthogonal to this main plane.
• the transmission direction is at least substantially orthogonal to the main plane of each layer.
• the transmission direction is non-orthogonal, more or less inclined relative to the normal to the main plane of each layer, that is to say, with respect to the direction of the thickness of each layer.
• a waveguide according to the invention is formed of a plurality of printed circuit board (PCB) plates stacked one on top of another by adhesive films.
• PCB printed circuit board
• Each circuit board manufacturing plate comprises at least one dielectric material thickness, said substrate, and at least one thickness of electrically conductive material applied to at least one main face of the substrate.
• Each adhesive film interposed between two printed circuit manufacturing plates constitutes an interlayer dielectric layer.
• the guide channels may be formed at least in part by a method of etching / depositing circuit board manufacturing boards.
• Such an etching / deposition method makes it possible in particular to make holes through the thickness of each plate or the thickness of electrically conductive material of each plate and / or to deposit an electrically conductive material, such as copper, for forming tracks on the surface of the substrate or vias or vias veneers (a via is a connection in electrically conductive material, generally in the form of a cylinder of hollow or full revolution, formed in or through the thickness of at least a layer of dielectric solid material, see, for example, "Electromagnetics for High-Speed Analog and Digital Communication Circuits" by Ali M. Niknejad, published in 2007).
• a waveguide according to the invention comprises several stackings of layers superimposed on each other, the different stacks being juxtaposed two by two next to each other, at least one transition device. being formed between two juxtaposed stacks, that is to say between two coupled guide channels extending respectively in each stack and parallel to the main plane of the layers of each stack.
• the transmission direction is therefore parallel to the main plane of the layers of each stack, and the longitudinal direction of the adaptation channels may be orthogonal to the main plane of the layers of each stack.
• each stack may in particular be formed of a plurality of printed circuit boards stacked on each other by adhesive films. Other embodiments of each stack may be envisaged for example as indicated above.
• each adaptation wall of at least one adaptation channel is formed of a metal layer.
• a metal layer may be a metal blade or a plurality of separate electrically conductive vias juxtaposed parallel to each other.
• an adaptation channel comprises two adaptation walls, each adaptation wall being formed by a metal blade.
• an adaptation channel comprises two adaptation walls, each adapter wall being formed by a plurality of electrically conductive vias.
• an adaptation channel comprises a first adaptation wall formed by a metal blade and a second wall formed by a plurality of electrically conductive vias.
• Such a plurality of juxtaposed vias is, from the point of view of the transmission of the electromagnetic wave, equivalent to a continuous metal blade, since the distance separating two adjacent vias is less than a predetermined distance. depending on the wavelength of the electromagnetic wave.
• the realization of a waveguide wall by juxtaposed vias has the advantage of allowing a collective manufacturing by fast and economical etching / depositing processes, using traditional machines already widely in operation at the scale. industrial.
• each via an adapter wall extends along said intermediate dielectric layer from a coupling end of a guide channel coupled in the longitudinal direction of the channel. adaptation.
• each via an adapter wall extends orthogonally to the longitudinal direction of the adapter channel and to the transmission direction.
• the intermediate dielectric layer is interposed between two of said superposed layers in which the coupled guide channels extend.
• each adaptation wall extends between the intermediate dielectric layer and one of the previous superimposed layers.
• the intermediate dielectric layer is interposed between two dielectric substrate layers in which the coupled guide channels extend.
• each adapter wall extends between the intermediate dielectric layer and one of the dielectric substrate layers.
• each layer of a multilayer waveguide according to the invention in which a guide channel extends coupled comprises a thickness of a solid and rigid dielectric material, said substrate, common to the different layers of the waveguide superimposed on each other in pairs by means of an intermediate dielectric layer which may or may not be formed of same substrate.
• guide channels are described in the publication "A Multilayer LTCC Solution for Integrating 5G Access Point Antenna Modules," F. Foglia Manzillo et al., In IEEE Transactions on Microwave Theory and Techniques, Vol. 64, no. 7, pp. 2272-2283, July 2016.
• the intermediate dielectric layer is disposed between faces, called coupling faces, of two dielectric substrate layers.
• the coupling ends of the guide channels open on these coupling faces.
• the adaptation walls of each adaptation channel are placed between a coupling face of one of the dielectric substrate layers comprising a coupled guide channel and the intermediate dielectric layer of the transition device.
• the matching channels are parallel to the assembly faces of the dielectric substrate layers.
• a device for transitioning a waveguide according to the invention thus makes it possible to ensure electromagnetic wave transmission between coupled guide channels of several superimposed layers while minimizing energy losses.
• each coupled guide channel is delimited by at least two electrically conductive walls, called guide walls, spaced apart from each other.
• guide walls electrically conductive walls
• this guide channel is called "parallel plate waveguide”.
• each coupled guide channel is delimited by pairwise parallel guide walls and arranged to form a polygonal - especially rectangular - cross-sectional cross section of the coupled guide channel.
• a guide channel may be referred to as a "rectangular waveguide” (often referred to by the acronym RW, from the English “rectangular waveguide”).
• RW rectangular waveguide
• the transition device adaptation walls may be peripheral walls of the terminal end. coupling of each guide channel.
• a guide wall may be formed of a plurality of electrically conductive vias juxtaposed parallel to each other.
• each guide wall of at least one coupled guide channel is a metal plate.
• each guide wall of at least one coupled guide channel is formed of a plurality of electrically conductive vias.
• At least one guide wall of at least one coupled guide channel is formed of a metal plate and at least one other guide wall of this coupled guide channel is formed of a plurality of electrically conductive vias.
• a guide channel whose guide walls are formed by juxtaposed vias can guide an electromagnetic wave similarly to a guide channel whose guide walls are formed by metal plates.
• the orientation of the vias is the same on two parallel guide walls of a coupled guide channel.
• the vias are oriented in the same direction as that of a field E relative to the electromagnetic mode that is desired in the guide channel.
• the vias are oriented orthogonally to the direction of a field E relative to the electromagnetic mode that is desired to have in the guide channel.
• the vias of at least one guide wall of at least one guide channel extend parallel to the direction of transmission.
• the vias of the guide walls of two coupled guide channels are aligned with respect to one another. improves the transmission of an electromagnetic wave between these coupled guide channels.
• the vias of at least one guide wall of at least one guide channel extend orthogonally to the direction of transmission.
• the invention also extends to an antenna comprising at least one waveguide according to the invention.
• an antenna according to the invention may be an antenna having a structure of the so-called CTS type, of the English “Continuous Transverse Stub" as described for example by US6101705.
• the invention also extends to a method for manufacturing a multilayer electromagnetic waveguide comprising a plurality of superposed layers forming channels for guiding an electromagnetic wave, and at least one transition device comprising at least one intermediate dielectric layer. between two guide channels, called coupled guide channels, extending in a direction of transmission of an electromagnetic wave between said guide channels coupled via the transition device,
• each transition device comprises at least one adaptation channel extending from the coupled guide channels, in a longitudinal direction secant to the direction of transmission,
• each adaptation channel is delimited by at least two electrically conductive walls, called adaptation walls, spaced from one another by said intermediate dielectric layer of said transition device, each adaptation wall extending according to the longitudinal direction along said intermediate dielectric layer from one end, said coupling end, of a coupled guide channel, and at least one adaptation wall extending in the longitudinal direction over a length chosen to obtain an impedance, said input impedance, at least substantially zero between the adaptation walls of this adaptation channel at the coupling ends of the guide channels coupled to optimize the transmission of an electromagnetic wave between the two coupled guide channels.
• the invention also relates to a multilayer waveguide comprising a device for transitioning two guide channels of the multilayer waveguide, a method of manufacturing such a multilayer waveguide and an antenna comprising such a guide.
• multilayer wave characterized in combination by all or some of the features mentioned above or below.
• FIGS. 1 to 5 are schematic perspective views of multilayer waveguides according to five embodiments of the invention.
• FIG. 6 is a schematic view in longitudinal section of the multilayer waveguide of FIG. 1, the guide channels of which are not perfectly aligned,
• FIG. 7 is a first diagram of the equivalent circuit of a multilayer waveguide according to the invention comprising two guide channels and an adaptation device,
• FIG. 8 is a second diagram of the equivalent circuit of a multilayer waveguide according to the invention comprising two guide channels and an adaptation device,
• FIG. 9 is a schematic perspective view of a multilayer waveguide according to a sixth embodiment of the invention.
• FIGS. 10 and 11 are diagrammatic views in longitudinal section of a multilayer waveguide according to different embodiments having two guide channels extending orthogonally with respect to each other,
• FIGS. 12 and 13 are diagrammatic views in longitudinal section of a multilayer waveguide according to various embodiments adapted to form a power divider
• FIG. 14 is a diagrammatic longitudinal sectional view of a multilayer waveguide according to an embodiment according to the invention; comprising five layers of substrate forming a multilayer supply network said candlestick,
• FIG. 15 is a diagrammatic sectional view in the thickness of an example of an antenna structure part according to the invention with radiating slots,
• FIG. 16 is a schematic longitudinal sectional view of a multilayer waveguide according to another embodiment of the invention comprising five substrate layers forming a multilayer power supply network said candlestick.
• a multilayer waveguide 20 according to the invention as shown in FIGS. 1 to 6 and 8 comprises at least two guide channels 21.
• Each guide channel 21 extends longitudinally in a direction of transmission 22 and is delimited transversely by at least two electrically conductive walls, said guide walls 23, spaced apart from each other by a dielectric material 24. Thus, each guide channel 21 serves to guide an electromagnetic wave between its guide walls 23.
• the guide channels 21 have the same characteristic impedance Z cl .
• the guiding walls 23 delimiting transversely a guide channel 21 are, moreover, symmetrical in pairs with respect to a plane, called a transmission plane, parallel to these guide walls 23 and equidistant from the guide walls 23, this transmission plane. being a median plane of the guide channel 21.
• the dielectric material 24 interposed between two walls 23 for guiding a guide channel 21 may be air or any other suitable dielectric solid material.
• the dielectric element 24 has a relative dielectric permittivity coefficient of between 1 and 10, nevertheless nothing prevents to have such a coefficient greater than 10.
• the guide channels 21 of the multilayer waveguide 20 are integrated in layers 25 of the same solid and rigid dielectric material, said substrate, of the multilayer waveguide 20 superimposed in pairs.
• the substrate used is chosen according to the applications of the multilayer waveguide.
• the substrate is generally an organic substrate of low relative dielectric permittivity, that is to say lower
• the substrate may be a composite material formed of polytetrafluoroethylene and glass fibers such as RT / duroid® 5880 for transmitting high frequency electromagnetic waves.
• each layer 25 is a printed circuit board (PCB).
• PCB printed circuit board
• Each layer 25 then comprises a thickness of dielectric material, said substrate, and a thickness of electrically conductive material applied on its two main faces of the substrate.
• Each substrate layer 25 has at least one external face, called the coupling face, so that, when the substrate layers 25 are superimposed, a coupling face of a substrate layer 25 faces a coupling face. another layer superimposed.
• the coupling faces of the substrate layers 25 are flat and parallel to each other.
• the layers of the waveguide are more easily superimposable.
• a multilayer waveguide according to the embodiment of the invention shown in Figure 1 comprises two guide channels 21, said guide channels 21 coupled, extending axially but being separated from each other so that to have an absence of electrical contact between these two guide channels 21.
• An end, called the coupling end, of a coupled guide channel 21 is thus opposite a coupling end of another coupled guide channel 21 so that an electromagnetic wave can be transmitted between these two channels 21 coupled guide.
• the two coupled guide channels 21 are respectively integrated in two separated substrate layers 25 away from each other.
• An electromagnetic wave can then be transmitted between these two substrate layers of the multilayer waveguide.
• the substrate layers of the multilayer waveguide 20 are thus superimposed so that the coupling ends of the coupled guide channels 21 of two superimposed substrate layers 25 are facing each other but distant from each other. the other.
• the transmission direction 22 is preferably orthogonal to the coupling face of each substrate layer 25.
• each coupled guide channel 21 is delimited transversely by two guide walls 23.
• the guide channel 21 is thus a parallel plate waveguide.
• each coupled guide channel 21 is delimited by two parallel metal plates 26 of the same dimensions.
• the guide walls 23 delimiting the same side of two coupled guide channels 21 are placed on the same plane so that the two coupled guide channels 21 are perfectly aligned.
• the multilayer waveguide 20 comprises, for each pair of coupled guide channels 21, a device 28 for transitioning the two coupled guide channels 21.
• This transition device 28 comprises an intermediate dielectric layer 29 disposed between the two substrate layers 25 comprising the coupled guide channels 21.
• this intermediate dielectric layer 29 may be an adhesive film or an adhesive layer for assembling the substrate layers one on the other.
• the adhesive film may for example consist of a fabric pre-impregnated with resin.
• the interlayer dielectric layer 29 has, for example, a relative dielectric permittivity coefficient of between 2 and 4, more particularly of the order of 2.5.
• the dielectric layer 29 has a lower thickness than the thickness of each of the two layers of substrate it connects.
• the thickness of the dielectric layer 29 is, for example, less than the electromagnetic wave length ⁇ which propagates in the same dielectric layer 29.
• the dielectric layer 29 has a thickness less than ⁇ / 10, preferably less than ⁇ / 100.
• the dielectric layer 29 may be formed of an air layer. This layer of air can be unwanted, due to manufacturing errors, particularly during the manufacture of hollow waveguides.
• the substrate layers 25 are then assembled to one another by a mechanical assembly device such as screws or by pressing, for example.
• the transition device 28 also comprises at least one matching channel 30 extending from the coupled guide channels, each matching channel 30 extending in a longitudinal direction secant to the direction of transmission, between the two layers. 25 comprising the two coupled guide channels 21.
• each channel 30 of adaptation is delimited by two electrically conductive walls, said walls 36 of adaptation, spaced apart from each other by the dielectric layer 29 interposed.
• Each matching wall 36 extends between a substrate layer 25 comprising a coupled guide channel 21 and the intermediate dielectric layer 29.
• at least one transition device comprises a single adaptation channel extending on one side only from the coupled guide channels, according to a longitudinal direction secant to the direction of transmission.
• At least one transition device comprises at least two adaptation channels extending opposite each other from the coupled guide channels. , each adaptation channel extending in a longitudinal direction secant to the transmission direction.
• Each adaptation duct 30 extends in a longitudinal direction 31, secant to the transmission direction 22, over a predetermined length, called length l of adaptation, from the guide walls 23 of the guide channels 21 coupled at the coupling ends facing each other of the coupled guide channels 21, and away from these coupled guide channels 21.
• a first channel 30 for adapting the transition device 28 for two coupled guide channels 21 has a first adaptation wall 36 extending orthogonally to the direction of transmission 22 from a first guide wall 23. a first guide channel 1 coupled at its coupling end.
• the first adaptation channel comprises also a second adaptation wall 36 extending orthogonally to the transmission direction 22 from a first guide wall 23 of a second guide channel 21 coupled at its coupling end, the first wall 23 of guiding the first guide channel 21 and the first guide wall 23 of the second guide channel 21 being placed on the same side of the transmission plane.
• a second channel 30 for adapting the transition device 28 has a first adaptation wall 36 extending orthogonally to the direction of transmission 22 from a second wall 23 for guiding the first guide channel 21 at its level. coupling end.
• the first adaptation channel 30 also comprises a second adaptation wall 36 extending orthogonally to the direction of transmission 22 from a second wall 23 for guiding the second guide channel 21 at its coupling end.
• Each wall 36 of adaptation can be formed by a blade, said blade 32 of adaptation, electrically conductive.
• Each adaptation blade 32 extends along the length / of adaptation from a coupling end of an adaptation guide channel 21 and has a width equal to the width of this coupling end of this channel 21 guide.
• a matching conductive blade 32 is orthogonal to the transmission direction 22.
• the adapter blades 32 may be disposed against the dielectric substrate layers 25.
• a coupled guide channel 21 is delimited by two guide walls 23, each guide wall 23 being formed by a row of vias 27 juxtaposed so as to form a plate waveguide. parallel.
• the vias 27 of the two guide walls 23 are preferably symmetrical to one another with respect to the transmission plane of the guide channel 21.
• the vias 27 may be oriented in the direction of transmission 22 as shown in Figure 2 or otherwise orthogonal to the direction of transmission 22 as shown in Figure 3 according to the electromagnetic mode that is desired in the guide channel.
• the vias 27 of a guide channel 21 are generally integrated in a dielectric substrate layer 25 and pass through the thickness from one side to the other.
• the vias are oriented orthogonally to the direction of a field E relative to the electromagnetic mode that is desired to have in the guide channel.
• the juxtaposed vias 27 forming a guide wall 23 are spaced from each other by a given distance, for example of the order of the diameter of the vias, so that a vias row is similar to a metal wall with respect to a electromagnetic wave transmission.
• the arrangement of the vias 27 of a guide wall 23 is for example described by J. Hirokawa and M. Ando, "Single-layer feed waveguide of waves for plane wave excitation in parallel plates," IEEE Trans. Antennas Propag., Vol. 46, no. 5, pp. 625-630, May 1998, and by D. Deslanders, K. Wu, "Accurate modeling, wave mechanisms, and design considerations of a substrate integrated waveguide.” Trans.
• the guide channels 21 are delimited by two metal plates 26 parallel to one another and each adaptation wall 36 of each adaptation channel 30 is formed by a row of vias 33 juxtaposed parallel to each other. to each other and extending along the longitudinal direction of the adaptation channel 30. More particularly, the vias 33 extend along said intermediate dielectric layer 29 from a coupling end of a coupled guide channel 21.
• FIG. 7 represents an equivalent diagram of a multilayer waveguide according to the invention having two guide channels coupled by two adaptation channels.
• Each matching channel has a terminal impedance load Z R , at its end in said longitudinal direction opposite to the coupled guide channels 21, which has a finite and non-zero value, representative of the fringe field phenomena. radiation effects occurring at the ends of each adaptation channel opposite to the guide channels.
• This terminal load is equivalent to a resistance in parallel with a capacitor at this end of the adaptation channel. This terminal charge implies that each channel
• the adaptation is not terminated by either a short circuit or an open circuit.
• Zco > ? 7o being the impedance of an electromagnetic wave in the vacuum, e ⁇ 2.718, ⁇ 1.781, ⁇ 0 the wavelength of the wave transmitted in the vacuum, t being the thickness of the layer 29 and W being the width of the adapter channel (see N. Marcuvitz, Waveguide Handbook, 3rd ed., New York, NY, USA: McGraw-Hill, 1951).
• the length / adaptation of each adaptation channel, and therefore of at least one adaptation wall is chosen to obtain an impedance of input Z AA >, Z BB > of this adaptation channel at least substantially zero.
• the input impedance Z AA >, Z BB > of an adaptation channel is the impedance Z R of the terminal load reduced to the input AA ', BB' of the adaptation channel.
• the value of the impedance Z R of this terminal load depends in particular on the thickness and the permittivity of the intermediate dielectric layer and on the permittivity of the superposed layers forming guide channels.
• Adjustment of the adaptation length of each adaptation channel makes it possible to obtain a low impedance, ideally zero (short circuit), between the two coupled guide channels so as to improve the transmission of an electromagnetic wave by minimizing in particular the energy losses.
• the adaptation length l of each adaptation channel may for example be chosen between ⁇ , ⁇ and 0, 5 ⁇ , in particular between 0.2 ⁇ and 0.3 ⁇ . Therefore, the design of a transition device according to the invention is simple and fast.
• FIG. 8 represents another equivalent diagram of a multilayer waveguide according to the invention having two guide channels coupled by two adaptation channels. This equivalent diagram is valid for any thickness of the intermediate dielectric layer.
• Each matching channel has a terminal impedance load Z R , at its end in said longitudinal direction opposite to the coupled guide channels 21, which has a finite and non-zero value, representative of the fringe field phenomena. radiation effects occurring at the ends of each adaptation channel opposite to the guide channels.
• This terminal load is equivalent to a resistance in parallel with a capacitor at this end of the adaptation channel.
• transition region between the matching channels and the guide channels is considered a junction of four four-port waveguides.
• the coefficients of a distribution matrix [£] associated with this junction can be obtained by numerical simulation.
• the adaptation length of each adaptation channel is then determined from these coefficients.
• a transition device 28 can be designed quickly and easily.
• a multilayer waveguide according to the embodiment shown in FIG. 9 comprises two parallelepiped coupled guide channels 21.
• each coupled guide channel 21 is delimited by four mutually parallel parallel two guide walls 23 and two by two orthogonal ones.
• Such guide channels 21 thus form rectangular waveguides.
• Each guide wall 23 is formed by a metal plate 26.
• the transition device 28 then comprises four adaptation channels 30 between the two guide channels 21.
• the four matching channels are orthogonal two by two.
• each wall 36 for adapting an adaptation channel 30 is formed of a metal blade extending from a wall 23 for guiding a coupled guide channel 21.
• the walls 36 adaptation of the transition device 28 may be peripheral walls of the coupling ends of the guide channels.
• the length / of adaptation of two adaptation walls 36 of a first adaptation channel may be different from that of two walls 36 of adaptation of a second adaptation channel orthogonal to the first adaptation channel.
• a transition device 28 according to the invention makes it possible to improve the transmission of an electromagnetic wave between the coupled guide channels 21 by minimizing the energy losses, as well as the reflection of the electromagnetic waves transmitted between two coupled guide channels 21. .
• it provides in the two coupled guide channels 21 separated from each other a transmission of an electromagnetic wave similar to that which would be obtained with a continuous waveguide.
• the frequency of the transmitted electromagnetic wave is 30 GHz.
• the layers of the comparative multilayer waveguides consist of a relative permittivity substrate equal to 2.2.
• the results were obtained by software simulation with a 3D electromagnetic solver simulation software, namely ANSYS HFSS®, marketed by ANSYS, Inc., Canonsburg, Pennsylvania, USA
• Other simulation software such as CST STUDIO SUITE® , sold by CST of America®, Inc., Framingham, Massachussets, USA, or COMSOL Multiphysics®, marketed by COMSOL, Inc., Burlington, Massachussets, USA, or others, may be used.
• a transmission coefficient of the order of -0.0 dB is obtained and a coefficient of reflection of the order of -70dB.
• a transmission coefficient of the order is obtained; -4dB and a reflection coefficient of the order of -5dB.
• a transmission coefficient of the order of - 0.04dB and a reflection coefficient of the order of -45dB is obtained.
• a transition device 28 according to the invention is therefore robust with respect to misalignments of the coupled guide channels 21, which cause little loss of energy.
• a transmission coefficient is obtained. order of -0.03dB and a reflection coefficient of the order of -85dB.
• a multilayer waveguide not according to the invention comprising two superposed rectangular section guide channels which are not in electrical contact, comprising an intermediate dielectric layer consisting of air of thickness ⁇ between the two guide channels and do not include transition device 28 according to the invention, each guide channel being delimited by four orthogonal guide walls in pairs, a transmission coefficient of the order of -3 dB and a reflection coefficient of order of -5dB.
• a multilayer waveguide according to the embodiment of the invention shown in FIG. 8 comprising an air layer of thickness ⁇ as a dielectric layer 29 inserted between the two layers 25 of the guide multilayer waveguide 20, as well as blades 32 for matching adaptation lengths equal to 2.6 mm for two first matching channels opposite one another and 0.25 mm for two other channels of adaptation opposed to each other and orthogonal to the first two matching channels, we obtain a transmission coefficient of the order of -0.04dB and a reflection coefficient of the order of -55dB.
• FIGS. 10 to 13 show multilayer waveguides according to the invention that can be used as a base block (assembly of guide channels coupled in a T-shape, in particular for the splitters of FIG. power, and guide channels coupled perpendicular to each other) for the design of multilayer waveguides of more complex structure, antennas.
• FIG. 10 shows a multilayer waveguide according to the invention which comprises two substrate layers 25 of which a first substrate layer, called the lower substrate layer, comprises a guide channel extending in a direction of transmission and a second substrate layer, referred to as the upper substrate layer, comprises a guide channel extending orthogonally to the transmission direction.
• the transition device 28 comprises two adaptation channels coupling the guide channel of the lower substrate layer to one end of the guide channel of the upper substrate layer.
• the adaptation wall of the transition device 28 placed in contact with the coupling face of the upper substrate layer extends along the guide channel of the upper substrate layer so as to delimit it and allow guiding an electromagnetic wave in this guide channel.
• FIG. 11 shows an alternative embodiment of the multilayer waveguide of FIG. 10, the transition device 28 comprising a single adaptation channel.
• the multilayer waveguide comprises two substrate layers.
• a first substrate layer called a lower substrate layer, comprises a guide channel extending in a transmission direction.
• a second substrate layer referred to as the upper substrate layer, comprises a guide channel extending orthogonally to the transmission direction.
• the single matching channel coupling the guide channel of the lower substrate layer to one end of the guide channel of the upper substrate layer, extends orthogonally to the direction of transmission away from the guide channel. of the upper substrate layer.
• the guide channel of the upper substrate layer is delimited by a metallized wall disposed between the lower substrate layer and the intermediate dielectric layer extending along the two substrate layers of the multilayer waveguide so as to allow the guiding of an electromagnetic wave in the guide channel of the upper substrate layer while providing electrical contact with a guide wall of the guide channel of the lower substrate layer.
• the guide channel of the upper substrate layer therefore partly comprises the intermediate dielectric layer.
• FIG. 12 presents a multilayer waveguide according to the invention making it possible to obtain a power divider at one input and two outputs.
• the multilayer waveguide has four substrate layers, a first substrate layer comprising a guide channel extending in a transmission direction and being connected to a guide channel of a second superimposed substrate layer. to the first layer, the latter channel extending orthogonally to the direction of transmission.
• a third substrate layer superimposed on the second substrate layer also comprises two coupled guide channels extending in the transmission direction opening on a coupling face of the third substrate layer.
• One of the guide channels of the third substrate layer is connected to one end of the guide channel of the second substrate layer, and the other guide channel is connected to another end of this guide channel.
• a fourth substrate layer 25 comprises two coupled guide channels extending in the transmission direction, one of these guide channels being positioned opposite a guide channel of the third substrate layer and the other channel coupled guide means of the fourth substrate layer facing the other guide channel of the third substrate layer.
• a first transition device 28 is respectively placed between a first coupled guide channel of the fourth substrate layer and the coupled guide channel opposite the latter of the third substrate layer.
• a second transition device 28 is respectively placed between the other coupled guide channel of the fourth substrate layer and the coupled guide channel opposite the latter of the third substrate layer.
• the intermediate dielectric layer 29 is placed between the third substrate layer and the fourth substrate layer.
• the transition devices 28 comprise two adaptation channels.
• the matching channels are orthogonal to the direction of transmission.
• FIG. 13 shows a multilayer waveguide according to an alternative embodiment of FIG. 12.
• the multilayer waveguide has two substrate layers, a first substrate layer, called a lower substrate layer, comprising a first guiding extending in a transmission direction and being connected to a second guide channel of the lower substrate layer orthogonal to the transmission direction.
• a second substrate layer, called the upper substrate layer, comprises two guide channels.
• a first guide channel of the upper substrate layer is coupled with an end of the second guide channel of the lower substrate layer.
• the second guide channel is coupled to the other end of the second guide channel of the lower substrate layer.
• the guide channels of the upper substrate layer are positioned facing the ends of the second guide channel of the lower substrate layer.
• a first transition device 28 is placed between the first coupled guide channel of the upper substrate layer and the second guide channel of the lower substrate layer.
• a second transition device 28 is placed between the coupled second guide channel of the upper substrate layer and the second guide channel of the lower substrate layer.
• the transition devices 28 comprise two adaptation channels.
• the two transition devices 28 have a common matching wall between the ends of the second guide channel of the lower substrate layer so as to define this second guide channel and allow the guidance of an electromagnetic wave in this second channel. guidance between its ends.
• the common matching wall is a metallized wall placed on the lower substrate layer.
• FIG. 14 shows a multilayer waveguide according to the invention comprising five substrate layers superimposed on each other making it possible to obtain a so-called candlestick supply network (see for example US Pat. No. 7,432,871).
• a guide channel, extending in a transmission direction, of the first substrate layer is coupled by a transition device to a guide channel, extending orthogonally to the transmission direction, of a second substrate layer to the first substrate layer.
• the transition device between the first and the second substrate layer comprises two adaptation channels. Each of these adaptation channels has an adaptation wall extending along the guide channel of the second substrate layer so as to delimit it.
• a first end of the guide channel of the second substrate layer is coupled by a transition device to a first guide channel, extending in the transmission direction, of a third substrate layer.
• a second end of the guide channel of the second substrate layer is coupled by another transition device to a second guide channel, extending in the transmission direction, of the third substrate layer.
• the transition devices between the second and third substrate layers each have two matching channels, as shown in FIG. 11.
• a first guide channel of the third substrate layer is coupled to a first end of a first a guide channel, extending orthogonally to the direction of transmission, of a fourth substrate layer, as shown in FIG. 12.
• a second guide channel of the third substrate layer is coupled to a first end of a second guide channel, extending orthogonally to the direction of transmission, of a fourth substrate layer.
• a second end of the first guide channel of the fourth substrate layer is coupled by a transition device to a first guide channel, extending in the transmission direction, of a fifth substrate layer.
• a second end of the second guide channel of the fourth substrate layer is coupled by a transition device to a second guide channel, extending in the transmission direction, of the fifth substrate layer.
• each transition device between the fourth and the fifth substrate layer comprises two adaptation channels.
• Each guide channel of the fourth substrate layer is delimited by an adaptation wall of the adaptation channel with which it is associated.
• a multilayer waveguide 20 according to the invention can be incorporated into an antenna as shown in FIG. 15.
• the antenna is made by adding radiating slots on the upper face of the multilayer waveguide 20 shown in Figure 14 for example.
• FIG. 16 shows an alternative embodiment of the multilayer waveguide of FIG. 14.
• This multilayer waveguide differs from that shown in FIG. 14 in that the transition devices between the first substrate layer and the second layer of the substrate, between the third substrate layer and the fourth substrate layer and between the fourth substrate layer and the fifth substrate layer comprise a single adaptation channel.
• a multilayer waveguide according to the invention can be manufactured by etching the adaptation walls 36 of the matching channels 30 over the electrically thick material. conductor applied on at least one main face of the substrate of each layer 25.
• each adaptation wall 36 is formed of the electrically conductive material of the layers 25.
• the guide walls 23, formed of vias 27 or metal plates 26 are manufactured in the layers 25 of the multilayer waveguide by methods known to those skilled in the art.
• a multilayer waveguide according to the invention may also be made by additive manufacturing of layers of polymer material and by deposition of an electrically conductive material on at least one surface of the layers of polymer material.
• the adaptation walls 36 of the adaptation channels 30 are then etched on the thickness of applied electrically conductive material.
• the layers, once etched, are then assembled together by gluing with an adhesive film.
• a multilayer waveguide 20 according to the invention can also be made from metal parts delimiting the guide channels and the adaptation channels.
• the space between the metal parts defining the guide channels or the adaptation channels can be filled with air or a dielectric foam.
• a multilayer waveguide according to the invention can therefore be manufactured with methods known to those skilled in the art.
• the manufacture of a multilayer waveguide 20 is thus simple and quick to implement.
• the manufacturing defect tolerance of a multilayer waveguide according to the invention facilitates manufacture by accepting a margin of misalignment of the coupled guide channels.
• the invention therefore relates to a multilayer waveguide 20 comprising a device 28 for transitioning two guide channels 21 extending from a multilayer waveguide 20, each guide channel 21 comprising at least two electrically conductive walls.
• the transition device 28 makes it possible to improve the transmission of the electromagnetic waves between the guide channels 21, the transition device 28 comprising at least one adaptation channel 30, each adaptation channel being delimited by two electrically conductive walls.
• a multilayer waveguide, a method of manufacturing such a multilayer waveguide and an antenna according to the invention can be the subject of numerous alternative embodiments with respect to the embodiments shown in the figures.
• each guide wall may be formed of a plurality of juxtaposed rows of vias.
• the guide channel 21 may be delimited by four guide walls 23, each guide wall 23 being formed of at least one row, in particular at least two adjacent rows whose vias of a row are offset in the direction transmission relative to the vias of another row of this guide wall 23, for example by three adjacent rows of vias 27 placed in staggered rows.
• a multilayer waveguide according to the invention may comprise guide walls formed by at least one row of vias and adaptation walls formed by at least one other row of vias.
• a multilayer waveguide according to the invention can be used to design radars, satellite systems, circuits and multilayer waveguide antennas operating up to millimeter waves.
• a multilayer waveguide 20 according to the invention makes it possible, in particular, to produce antennas according to a CTS type structure as represented in FIG. 15.

Landscapes

• Waveguides (AREA)
• Waveguide Connection Structure (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=58162726

Family Applications (1)

Country Status (5)

Families Citing this family (4)

Family Cites Families (7)

• 2016
  • 2016-10-21 FR FR1660249A patent/FR3057999B1/fr not_active Expired - Fee Related
• 2017
  • 2017-10-16 ES ES17783526T patent/ES2834080T3/es active Active
  • 2017-10-16 US US16/343,258 patent/US10879577B2/en active Active
  • 2017-10-16 WO PCT/EP2017/076359 patent/WO2018073176A1/fr unknown
  • 2017-10-16 EP EP17783526.1A patent/EP3529852B1/de active Active

Also Published As

Similar Documents

Legal Events