Disclosed herein are various embodiments of sensor and/or antenna assemblies comprising signal confinement structures for preventing leakage and/or otherwise confining electromagnetic signals and/or waves from an operably coupled waveguide of the assembly. In preferred embodiments, such assemblies may comprise RADAR sensor modules for vehicles, including one or more novel and inventive features disclosed herein. For example, some preferred embodiments may comprise a rectangular-type waveguide and antenna with radiating slots suitable for mass fabrication but not requiring the commonly used substrate patch antennas.
In a more particular example of an antenna module, such as a vehicle RADAR module according to some embodiments, the module may comprise an antenna block defining a waveguide. A conductive layer may be coupled to the antenna block and may form, at least in part, a wall of the waveguide, such as a “cap” to a groove waveguide. A first periodic structure may be operably coupled to the waveguide and may comprise a first elongated opening and a first series of repeated slots extending at least substantially transverse to the first elongated opening, wherein each of the first series of repeated slots is spaced apart from an adjacent slot in the first series of repeated slots along the first elongated opening.
A second periodic structure may, similarly, be operably coupled to the waveguide, such as along an opposite side of the waveguide vis-à-vis the first periodic structure. The second periodic structure may also comprise a second elongated opening and a second series of repeated slots extending at least substantially transverse to the second elongated opening, wherein each of the second series of repeated slots is spaced apart from an adjacent slot in the second series of repeated slots along the second elongated opening.
In some embodiments, the waveguide may comprise a groove waveguide defined by opposing walls and the conductive layer. Alternatively, the waveguide may be defined by rows of posts defining a waveguide groove therebetween.
In some embodiments, each of the repeated slots of the first and second series of repeated slots may extend in both opposing directions at least substantially transverse from its respective elongated opening of the first and second elongated openings. In some such embodiments, each of the repeated slots of the first and second series of repeated slots may define a rectangular shape, such as a square shape.
In some embodiments, each of the repeated slots of the first and second series of repeated slots may comprise a first slot portion extending in both opposing directions at least substantially transverse from its respective elongated opening of the first and second elongated openings and a second slot portion intersecting the first slot portion and extending in both opposing directions at least substantially transverse from its respective elongated opening of the first and second elongated openings further than the first slot portion.
Some embodiments may further comprise a channel intersecting the first elongated opening at an end of the first elongated opening. In some such embodiments, the channel may extend at least substantially perpendicular to the first elongated opening and/or may intersect the second elongated opening at an end of the second elongated opening.
Some embodiments may further comprise one or more dielectric chambers, each of which may extend below or otherwise adjacent to each of the periodic structures. In some such embodiments, the dielectric chamber(s) may be defined by opposing rows of conductive vias extending along opposing sides of each of the first and second periodic structures.
In some embodiments, the first periodic structure may be formed along a first side of the waveguide and the second periodic structure is formed along a second side of the waveguide opposite the first side. In some such embodiments, the first elongated opening may extend along the first side of the waveguide at least substantially parallel to the waveguide and the second elongated opening may extend along the second side of the waveguide at least substantially parallel to the waveguide.
In an example of a radiofrequency signal confinement assembly according to some embodiments, the assembly may comprise a conductive layer having an elongated opening formed along a surface of the conductive layer. A dielectric chamber may extend underneath the elongated opening such that the elongated opening leads into the dielectric chamber. The assembly may further comprise a second conductive layer spaced apart from the conductive layer such that the dielectric chamber is formed in between the conductive layer and the second conductive layer.
Some embodiments may further comprise one or more periodic structures formed within the conductive layer, the periodic structure extending along an elongated axis. The periodic structure may comprise a series of repeated slots extending at least substantially transverse to the elongated opening, wherein each of the series of repeated slots is spaced apart from an adjacent slot in the series of repeated slots along the elongated opening.
Some embodiments may comprise one or more dielectric chambers, each of which may extend along a respective periodic structure underneath its respective elongated opening such that the elongated opening leads into the dielectric chamber. Such dielectric chamber(s) may comprise a PCB material or another suitable dielectric material. One or more of the walls/borders of the dielectric chamber(s) may be defined by a first row of conductive vias extending along a first side of the dielectric chamber and a second row of conductive vias extending along a second side of the dielectric chamber opposite the first side of the dielectric chamber. Alternatively, one or more of the walls/borders of the dielectric chamber(s) may be defined by a wholly conductive material adjacent to the material making up the dielectric chamber(s).
Some embodiments may further comprise a second conductive layer spaced apart from the conductive layer such that the dielectric chamber is formed in between the conductive layer and the second conductive layer.
In some embodiments, the elongated opening of the periodic structure(s) may extend at least substantially along a center of the dielectric chamber. The dielectric chamber is preferably wider than the width of the elongated opening, however.
Some embodiments may further comprise one or more channels that may intersect one or more elongated openings (some embodiments may comprise a channel intersecting two parallel elongated openings) at an end of the elongated opening. In some such embodiments, the channel may extend at least substantially perpendicular to the elongated opening.
Some embodiments may further comprise a dielectric chamber extending along the channel underneath the channel such that the channel leads into the second dielectric chamber. The dielectric chamber may interconnect with the second dielectric chamber.
Some embodiments may further comprise various other functional components, such as waveguides, antenna structures, feed structures, housings, etc. For example, some embodiments may further comprise an antenna block defining a waveguide. The periodic structure may then be operably coupled to the waveguide to confine a radiofrequency signal being delivered by the waveguide.
The features, structures, steps, or characteristics disclosed herein in connection with one embodiment may be combined in any suitable manner in one or more alternative embodiments.
Non-limiting and non-exhaustive embodiments of the disclosure are described, including various embodiments of the disclosure with reference to the figures, in which:
A detailed description of apparatus, systems, and methods consistent with various embodiments of the present disclosure is provided below. While several embodiments are described, it should be understood that the disclosure is not limited to any of the specific embodiments disclosed, but instead encompasses numerous alternatives, modifications, and equivalents. In addition, while numerous specific details are set forth in the following description in order to provide a thorough understanding of the embodiments disclosed herein, some embodiments can be practiced without some or all of these details. Moreover, for the purpose of clarity, certain technical material that is known in the related art has not been described in detail in order to avoid unnecessarily obscuring the disclosure.
The embodiments of the disclosure may be best understood by reference to the drawings, wherein like parts may be designated by like numerals. It will be readily understood that the components of the disclosed embodiments, as generally described and illustrated in the figures herein, could be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the apparatus and methods of the disclosure is not intended to limit the scope of the disclosure, as claimed, but is merely representative of possible embodiments of the disclosure. In addition, the steps of a method do not necessarily need to be executed in any specific order, or even sequentially, nor need the steps be executed only once, unless otherwise specified. Additional details regarding certain preferred embodiments and implementations will now be described in greater detail with reference to the accompanying drawings.
It should also be understood that although, in preferred embodiments, any number of antennae may be provided and therefore any desired number of corresponding antennae structures—such as a plurality of waveguides, grooves, etc.—may be provided, it is contemplated that some embodiments may comprise an array having a single antenna and therefore only a single waveguide, for example. Such antenna/waveguide/groove may curve about the block/assembly rather than be in a series of parallel lines in some embodiments. As another example, in some embodiments, grooves, slots, or the like may be arranged in a disc formation, or any other suitable formation, including linear, curved, etc. It should also be apparent that several of the accompanying figures depict only certain elements and/or aspects of antenna assemblies and/or waveguides and that, in order to properly function, other elements would typically need to be provided in a complete assembly/module, as those of ordinary skill in the art will appreciate.
In preferred embodiments, waveguide block 110 may comprise a casting, such as a casting comprising a Zinc or other suitable preferably metal material. However, in other contemplated embodiments, block 110 may instead, or in addition, comprise a plastic or other material. In some such embodiments, metallic inserts, coatings, or the like may be used if desired. In typical sensor assemblies, which, as previously mentioned, may be configured specifically for use in connection with vehicles, other structures may be combined with block/casting 110. For example, a slotted layer may be coupled to the waveguide block 110 in some embodiments, in some cases along with other layers and/or elements that are not depicted herein to avoid obscuring the disclosure, to form a more complete antenna assembly. In other embodiments, electromagnetic radiation may be emitted using other slots or openings not formed in a separate layer. For example, in some embodiments, slots may be formed directly in the waveguide block 110 itself.
Preferably, when a slotted layer is present, this layer comprises a metal or other conductive material. Such a slotted layer may be coupled with block 110 in a variety of possible ways. For example, an adhesive, solder, heat stakes, screws, other fasteners, and the like may be used to couple the slotted layer to block 110. Similar structures and/or techniques may be used to couple other layers or other elements of the assembly together, such as coupling the casting to a PCB, for example. In some embodiments, another layer, such as a layer of (preferably conductive) adhesive tape, may be inserted in between block 110 and the slotted layer, which may, either entirely or in part, be used to provide this coupling.
The bottom surface of substrate/PCB 130 is shown in
Chambers 132a, 132b, and 135 may, in some preferred embodiments, comprise dielectric chambers. In other words, these chambers may be made up of a dielectric material, such as, for example, a glass fiber reinforced (fiberglass) epoxy resin material or the like, a thermoplastic material, or a ceramic material. In some contemplated embodiments, the dielectric chambers may be empty and therefore may be occupied only by air. Although not depicted in
More particularly, these periodic structures comprise an elongated opening or slot 134 that preferably extends along a line that may run parallel, or at least substantially parallel, to the adjacent waveguide along one or more sides thereof. This structure is formed in a metallic/conductive layer 133 that is positioned immediately adjacent to the block 110 within which the waveguide or waveguides are formed. The zipper-like confinement structure further comprises a first series of repeated slots 136a formed along one side of opening 134 and a second series of repeated slots 136b formed along the opposite side of opening 134, both of which extend into the elongated opening 134. In the depicted embodiment, these opposing slots 136 are aligned with one another.
Each of the aforementioned openings/slots extends into a widened dielectric chamber 132 formed at the side of layer 130 opposite the metallic top layer 133. In preferred embodiments, opening 134 is centered, or at least substantially centered, with respect to chamber 132 and slots 136a/136b, which extend perpendicular to opening 134 in the depicted embodiment, extend only partially from opening 134 to the outer edges of chamber 132. As previously mentioned, chamber 132 preferably comprises a dielectric material, such as a typical material used to manufacture a PCB, such as FR4 material, for example. The outer edges of chamber 132 may be defined by metallic and/or conductive borders, which may either be continuous or, as described in greater detail below, may be defined by a plurality of spaced conductors, such as vias.
In some embodiments, these borders may extend the entire length of chamber 132. In other words, the material on either side of chamber 132 may be continuously metallic/conductive. However, as discussed in greater detail below, other embodiments are contemplated in which these borders may be defined by a series of vias or other spaced conductors, which may extend between opposing metallic/conductive layers of the assembly, such as between layer 133 and an opposing ground layer (not shown) of the assembly. It should be understood that this ground/opposing conductive layer would typically form a lid or other boundary for chamber 132 opposite opening 134.
More particularly, a first opening 534a preferably formed along a line extends parallel to a second opening 534b that also extends along a line adjacent thereto. Again, typically a waveguide structure would be formed in between openings 534a and 534b, such as in an adjacent structure layer coupled to layer 530. Again, a series of widened regions or repeated slots 536a are formed at repeating intervals along opening 534a and a corresponding series of widened regions or repeated slots 536b are formed at repeating intervals along opening 534b. In this embodiment, slots 536a and 536b extend in both opposing directions at least substantially transverse from its respective elongated opening 534a/534b. In addition, each of the repeated slots 536a and 536 comprises a rectangular shape.
At respective ends of elongated openings 534a/534b, a transverse opening or channel 538 is formed, which interconnects openings 534a/534b. Again, although the opposite end of these elongated openings 534a/534b is not shown in
A plan view of the opposite side of layer/structure 530 is shown in
The width of the lines of openings 534a/534b may be relatively thin. Thus, in some embodiments, this width may be just sufficient to be maintained even when the structure is under etched, which preferred thickness may therefore vary by application/material. The preferred width of the dielectric chambers 532a/532b beneath the line of openings 534a/534b may, in some embodiments, be about half the wavelength of the dielectric material used to form these chambers.
As for the repeating slot portions of the confinement structure, the period of these slots 536a/536b may be of the same order of magnitude as the guide wavelength of the mode propagating tangential to the line formed by openings 534a/534b. In embodiments in which the slots 536a/536b comprise rectangular shapes, these rectangles may, in some embodiments, comprise a length of about half the period of the repeating pattern (the length measured along the axis of the associated opening 534a/534b. However, it should be understood that the width of the dielectric chambers 532a/532b should typically be about half of the wavelength of the dielectric material used to form the chambers. In addition, the period of the slots 536a/536b may be similar to the guide wavelength. Alternatively, or additionally, the period of the slots 536a/536b may be similar to the high frequency beat wavelength between the wavelength in the waveguide and the chamber.
As also shown in
Signal confinement structures are formed adjacent to and are operably coupled with each of the waveguides 720. Thus, elongated slots or openings 734 are formed along opposing sides of the elongated axes of each of the waveguides 720. In addition, a series of repeating widened sections or slots 736 are formed along openings 734, which, as previously mentioned, are preferably formed in a metallic layer and/or portion of a PCB or other similar adjacent layer/structure of assembly 700. In the depicted embodiment, each of the slots 736 comprises a rectangular shape that extends in both directions vis-à-vis the elongated opening 734. Again, a wide variety of alternative shapes, sizes, and configurations are contemplated, however. In addition, the signal confinement structure may further comprise various transverse slots 738 that may be used to functionally and/or physically interconnect adjacent elongated openings 734 formed on opposing sides of a particular waveguide 720.
As also shown in
Each repeating slot therefore comprises a first slot portion 936 that extends in both opposing directions that are transverse, or at least substantially transverse, from its respective elongated opening 934. Each repeating slot further comprises a second slot portion 937 that intersects the first slot portion 936 and extends in both of the aforementioned opposing directions transverse, or at least substantially transverse, from its respective elongated opening 934 but to a further extent than the first slot portion 936 forming, in essence, a slot within a slot. Interconnecting/transverse channels 938 may be formed to connect opposing sides/portions of structure 930 if desired. Channel(s) 938 may act as a blockage structure as the phase front of the wave to be blocked is parallel to channel 938. Although not shown in
The alternative structure of the confinement structure of
Thus, dielectric chambers 1032 may be defined by opposing metallic/conductive layers/material on the top and bottom thereof and may be opened to allow for interaction with adjacent EM signals by virtue of the various openings 1034 and/or slots 1036. The opposing sides of the dielectric chambers 1032 may be defined in a variety of ways. For example, in the embodiment depicted in
However, unlike embodiments discussed in connection with previous figures, substrate 1130 may primarily comprise a dielectric material throughout with the exceptions of (1) a metallic/conductive layer or portion into which the aforementioned signal confinement structures may be formed; and (2) a plurality of conductive vias 1150 that may extend from the aforementioned conductive layer to a ground layer (not shown), for example. Thus, the opposing rows of vias 1150 may define opposing borders of respective dielectric chambers 1132 that are formed under respective openings 1134. Dielectric chambers 1132 may otherwise have any of the shapes, dimensions, and/or features previously mentioned.
A partial, phantom view of a signal confinement structure of another embodiment is shown in
More particularly, a confinement structure comprising a series of parallel, linear openings 1334 and a plurality of interconnecting linear openings 1335 are formed. Linear openings 1334 comprise a series of periodic slots 1336, as mentioned throughout this disclosure. In addition, as best shown in
It should also be understood that whereas preferred embodiments may be used in connection with vehicle sensors, such as vehicle RADAR modules or the like, the principles disclosed herein may be used in a wide variety of other contexts, such as other types of RADAR assemblies, including such assemblies used in aviation, maritime, scientific applications, military, and electronic warfare. Other examples include point-to-point wireless links, satellite communication antennas, other wireless technologies, such as 5G wireless, and high-frequency test and scientific instrumentation. Thus, the principles disclosed herein may be applied to any desired communication sub-system and/or high-performance sensing and/or imaging systems, including medical imaging, security imaging and stand-off detection, automotive and airborne radar and enhanced passive radiometers for earth observation and climate monitoring from space.
The foregoing specification has been described with reference to various embodiments and implementations. However, one of ordinary skill in the art will appreciate that various modifications and changes can be made without departing from the scope of the present disclosure. For example, various operational steps, as well as components for carrying out operational steps, may be implemented in various ways depending upon the particular application or in consideration of any number of cost functions associated with the operation of the system. Accordingly, any one or more of the steps may be deleted, modified, or combined with other steps. Further, this disclosure is to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope thereof. Likewise, benefits, other advantages, and solutions to problems have been described above with regard to various embodiments. However, benefits, advantages, solutions to problems, and any element(s) that may cause any benefit, advantage, or solution to occur or become more pronounced, are not to be construed as a critical, a required, or an essential feature or element.
Those having skill in the art will appreciate that many changes may be made to the details of the above-described embodiments without departing from the underlying principles of the invention. The scope of the present inventions should, therefore, be determined only by the following claims.