The invention relates to a multilayer antenna arrangement, in particular of a planar construction, in accordance with the preamble of claim 1.
A conventional multilayer antenna is known from DE 10 2006 027 694 B3.
The multilayer antenna of a planar construction known from this publication comprises an electrically conductive ground plane, a conductive radiation plane (which is arranged parallel to the ground plane at a distance therefrom) and a dielectric carrier, which is provided so as to be sandwiched between the ground plane and the radiation plane. Above the radiation plane a carrier means is arranged, on which an electrically conductive patch element is positioned. The carrier means for the patch element has a thickness or height which is less than the thickness or height of the patch element.
The patch element itself can be formed as a three-dimensional body, i.e. as a solid material. It is also possible for the patch element to consist of a metal plate or a metal sheet, which is provided, by cutting or punching for example, with circumferential webs, rims or the like, extending away from the dielectric carrier.
An antenna of this type is suitable in particular as a motor vehicle antenna, for example also for SDARS. For this purpose, a patch antenna of this type can be arranged on a common base arrangement alongside further emitter antennae for other services.
An antenna arrangement of this type, with a plurality of antennae which are disposed under a common hood, is known for example from EP 1 616 367 B1.
From the above-mentioned prior publication, a multifunctional antenna is known which comprises a base, on which four different antennae are arranged offset from one another in a longitudinal direction and are covered by a hood covering all the antennae. This is only one example of an antenna arrangement, in which four different antennae are used. In many cases, however, in a deviation therefrom, antenna arrangements are also required which need for example only one antenna means for SDARS and for example a further patch antenna for determining the geoposition, i.e. an antenna which is often referred to in short as a GPS antenna, independently of what principle they are based on and/or which operators these systems are provided by (the GPS positioning system, the Galileo system etc. are known).
An improved patch antenna which is superior to earlier antennae, in particular for receiving SOARS or comparable services broadcast by satellite and/or terrestrially at the same time, is known from the category-defining DE 10 2006 027 694 B3, which was mentioned at the outset.
If a patch antenna of this type is for example used with a further patch antenna provided for the GPS service, this basically results in a construction of the type which can be seen in
In this case, an improved multilayer antenna A is shown in a schematic cross-sectional view and has a construction of the type which is known for example from DE 10 2006 027 694 B3, which was mentioned at the outset and corresponds to WO 2007/144104 A1.
Additionally, in the antenna arrangement shown in
The object of the present invention is thus to improve an antenna arrangement of this type, optionally of a basic type which uses further antennae for further services (for example mobile communication services in various frequency ranges, etc.).
According to the invention, the object is achieved according to the features specified in claim 1. Advantageous embodiments of the invention are given in the sub-claims.
A surprising solution is provided in the scope of the invention whereby an antenna arrangement, which is comparable with the antenna arrangement of
In the solution according to the invention it is proposed that as regards the antenna, the additional patch antenna B shown in
In other words, the additional, second or secondary patch antenna, provided for example for GPS services, is positioned in the parasitic patch element, which is configured so as to be box-shaped or box-like and which is arranged, in relation to the first antenna A, above the associated radiation plane.
It is possible for part of the height of the further patch antenna to be buried in the box-shaped or box-like element. The upper side thereof may project over the circumferential rim of the box-shaped or box-like patch element of the first antenna.
However, it is also possible for the at least partial circumferential rim of the parasitic patch element of the first patch antenna to end above the surface of the further patch element, in such a way that the additional patch antenna is completely buried in the receiving space of the patch element which is provided with a circumferential rim or with circumferential rim portions.
The further patch antenna, provided in particular for GPS services, can in this case rest on and/or be fastened on the parasitic box-shaped or box-like patch element of the first patch antenna, with the interposition of an insulating layer.
It is also possible for the further patch antenna, provided in particular for GPS services, not to be provided with its own ground plane, but for the substrate to lie directly on the parasitic box-shaped or box-like patch element of the first patch antenna, in such a way that the parasitic patch element of the first patch antenna simultaneously also forms the ground plane of the further patch antenna.
Finally, it has been found within the scope of the invention that the parasitic patch element, which is formed at least in portions with a circumferential rim or a circumferential wall, can be formed on the lower side and/or on the circumferential rim side of the further patch antenna. In this way, the aforementioned box-shaped or box-like patch element is not actually formed as a separate component, i.e. completely or partially not provided as a separate component, but the corresponding electrically conductive portions of what is referred to as the box-shaped or box-like patch element are formed completely or in part as metallised layers on the corresponding portions of the further patch antenna.
In this case, the parasitic patch element of the primary antenna may be formed completely or in part from a metallised layer on the lower side and/or on the circumferential side walls of the further patch antenna. These steps may be performed during the production of the further patch antenna, specifically in a manner similar to the construction of the patch antenna itself, if an electrically conductive patch plane is applied to the substrate of a patch antenna of this type so as to lie in the transmission direction, and an electrically conductive ground plane in the form of a metal coating on the upper and lower side of the substrate of the patch antenna is applied to the opposite side. In this case, the parasitic further box-shaped or box-like patch element, which in the state of the art is provided above a radiation plane of a patch antenna, would not be present as a physically independent element.
The aforementioned metal coatings on the patch antenna, on the lower side thereof and/or on one or more of the circumferential side faces, need not be constructed over the entire periphery, but may have gaps in the circumferential direction, for example at the corner regions, may be of different heights, and may even be galvanically separated from the ground plane below or from the parasitic patch element below. The aforementioned metal coatings on the side faces may even extend as far as the upper side of the further patch antenna, but should be galvanically separated at that location from the actively fed antenna patch of the further antenna.
The shaping in particular of the further patch antenna, i.e. predominantly the shaping of the substrate, of the lower ground plane which may also simultaneously be the plane of the parasitic patch element of the first patch antenna, but also of the active patch plane provided on the transmission/receiving side, need not necessarily be square or rectangular. This plane may be configured so as to be n-polygonal and may even have further shapings deviating from a regular angular shape. Ultimately, the side walls of the substrate of the additional patch antenna and/or the side walls or side faces, which are provided there at least in portions and which extend away from the first patch antenna, need not necessarily be formed parallel to the axial direction of the patch antenna (i.e. perpendicular to the various ground and/or radiation planes), but may have rounded corners, angular corners etc. In this respect, too, no limitations are given.
The invention is described in greater detail in the following by way of drawings, in which, in particular:
In the following, reference is initially made to the embodiment of
It can be seen from the schematic cross-sectional view of
The upper side 5a and the lower side 5b of the dielectric carrier 5 are of a sufficient height or thickness, which generally corresponds to a multiple of the thickness of the ground plane 3. In contrast with the ground plane 3, which approximately consists merely of a two-dimensional plane, the dielectric carrier 5 is thus configured as a three-dimensional body with a sufficient height and thickness.
In a deviation from the dielectric body 5, a different type of dielectric or a different dielectric construction may also be provided, even using air or with a layer of air in addition to a further dielectric body. When air is used as a dielectric, a corresponding carrier means must then of course be provided, for example with stilts, bolts, pillars etc., in order to support and to hold the further parts, which are located above and are still to be explained in the following, of the patch antenna.
Formed on the upper side 5a opposite the lower side 5b is an electrically conductive radiation plane 7, which again can also be understood approximately as a two-dimensional plane. This radiation plane 7 is electrically fed and excited via a feeder 9, which preferably extends in the transverse direction, in particular perpendicular to the radiation plane 7, from below, through the base (chassis) S, the ground plane 3 and the dielectric carrier 5, in an appropriate hole or an appropriate channel 5c.
The internal conductor of a coaxial cable (not shown) is electrogalvanically connected to the feeder 9 and thus to the radiation plane 7 from a terminal 11, which is generally located below and to which the coaxial cable, not shown in greater detail, can be attached. The external line of the coaxial cable (not shown) is electrogalvanically connected to the ground plane 3 located below. Instead of the attached coaxial cable, a microstrip line can also be used and correspondingly connected.
The embodiment of
The radiation plane 7 positioned on the dielectric 5 may have the same contour or outline 7′ as the dielectric 5 located below. In the embodiment shown, the basic shape is likewise fitted to the outline 5′ of the dielectric 5 and formed so as to be square, but has flat portions 7″ (only shown in the plan view of
The aforementioned ground plane 3, and likewise the radiation plane 7 however, are considered in part as a “two-dimensional” plane, because the thickness thereof is so low that they in effect cannot be considered “three-dimensional bodies”. The thickness of the ground plane 3 and the radiation plane 7 is conventionally less than 1 mm, therefore generally less than 0.5 mm, in particular less than 0.25 mm, 0.20 mm or 0.10 mm.
The patch antenna disclosed thus far may for example consist of a patch antenna of the commercially conventional type, preferably of what is known as a ceramic patch antenna with a dielectric carrier layer S made of a ceramic material. In accordance with the further description, it results that in addition to the patch antenna disclosed thus far, a patch antenna in the sense of a stacked patch antenna A is further constructed, in which a parasitic patch element 13 is additionally provided above the upper radiation plane 7 (preferably so as to lie perpendicular to said radiation plane 7 and offset at a distance parallel thereto). This parasitic patch element 13 is configured in such a way as to have a three-dimensional structure in contrast to the aforementioned ground plane 3 and the radiation plane 7, with a height and thickness which are different from, i.e. greater than, those of the ground plane 3 or the radiation plane 7.
A carrier means 19 (in particular a dielectric carrier means) which has a thickness or height 17, and which supports and carries the parasitic patch element 13, is preferably used. This dielectric carrier means 19 preferably consists of an adhesive or mounting layer 19′, which may be formed as what is known as a double-sided adhesive or mounting layer. Commercially conventional double-sided adhesive tapes or double-sided adhesive foam tapes, adhesive pads or the like, which have an appropriate thickness as specified above, may be used for this purpose. This provides the option of simply fastening and mounting the aforementioned patch element 13 on the upper side of a commercially conventional patch antenna, in particular a commercially conventional ceramic patch antenna, by this means.
The stacked patch antenna A thus described is positioned on a chassis S, shown merely as a line in
The patch element 13 may for example consist of an electrically conductive, upwardly open box-shaped metal body with a corresponding longitudinal and transverse extent and sufficient height.
As can be seen from the three-dimensional view of
In the embodiment shown, the patch element 13 has a longitudinal extent and a transverse extent which on the one hand are greater than the longitudinal and transverse extent of the radiation plane 7 and/or on the other hand are also greater than the transverse and longitudinal extent of the dielectric carrier 5 and/or of the ground plane 3 disposed below.
As can be seen from the figures, the parasitic patch element, which rests or is fastened on the carrier means 19 in the manner of an upwardly open box, comprises a base plane or central plane 53″, which in the embodiment shown is provided with a circumferential rim or a circumferential web 53d (thus in general with an appropriate raised portion 53d), which rises transversely, in particular perpendicularly, from the plane of the base plane 53″, which is also parallel to the ground plane. A patch element 13 of this type may for example be produced by cutting and edging procedures from an electrically conductive metal sheet, it being possible for the circumferential webs 53d to be connected to one another in the corner regions electrically/galvanically, for example by soldering (it further being possible for more recesses to be formed in the central portion 53″, although this will not be discussed further in the following).
Above this secondary patch element 13 is disposed, as is shown in the further figures, a second patch antenna B. The second patch antenna B is dimensioned, in terms of the length and width thereof, in such a way that the measurements thereof are for example at least slightly smaller than the free internal longitudinal and transverse extent between the circumferential webs 53d of the parasitic patch element 13. This specifically provides the option of burying the patch antenna B in the interior 53a of the patch element 13 to various extents. In other words, the lowest level, i.e. the lowest boundary plane 101, is located in the interior 53a of the parasitic patch element 13, i.e. below the upper boundary plane 53c, which is defined by the upper circumferential edges of the webs, rims or outer walls 53d of the parasitic patch.
The second patch antenna B also in turn comprises a substrate (dielectric body) 105 comprising an upper side 105a and a lower side 105b, the active radiation plane 107 of the second or secondary patch antenna B being formed so as to lie in the transmission/receiving direction (i.e. remote from the patch antenna A) as an electrically conductive plane on the upper side 105a of the substrate 105, and the associated second ground plane 103 of the second patch antenna B being provided so as to lie facing the patch antenna A (i.e. on the lower side 105b).
It can be inferred from the drawings that a further channel or a further hole 105c is provided transverse, and in particular perpendicular, to the patch radiation planes (i.e. in the axial Z-direction of the whole antenna arrangement). This channel extends through the chassis 20, through the first or primary patch antenna A (i.e. through the ground plane thereof, the dielectric body and the radiation plane above), through the carrier means 19 attached thereto and the parasitic patch element 13, through an optionally following carrier layer for the second patch antenna B, and through the second ground plane 103 of the patch antenna B and through the dielectric carrier 105 up to the second radiation plane 107 above, i.e. to the second radiation plane 107 of the second patch antenna B.
Disposed on the lower side of the chassis 20 is a coaxial terminal, in such a way that the radiation plane 107 is fed via a feeder 109 extending in the channel. The external line of a coaxial connection cable is galvanically connected to the ground plane 3 at the terminal. A microstrip connection cable may of course also be provided in this embodiment instead of a coaxial connection cable.
In the embodiments disclosed thus far, the height 115 of the second patch antenna B (including a support and/or fastening and/or adhesive layer 111 optionally located on the lower side of the ground plane 103 adjacent to the upper side of the parasitic patch element 13) is greater than the height 117, i.e. greater than the circumferential rims 53d of the parasitic patch element 13. The height of the patch element may however also be the same height as the circumferential rims 53d of the parasitic patch element 13.
The sectional view of
It can thus be seen from
It can be seen from the view of
In the variant of
A further variant shown in
In the embodiment of
The cross-sectional view of
For the sake of completeness, it should further be noted that the dielectric carrier 5, the associated ground plane 3 below and the radiation plane 7, located above opposite the ground plane, of the first patch antenna A, as well as the dielectric carrier 105 of the second patch antenna B and the optionally provided ground plane 103, as well as the associated radiation plane 107, also need not necessarily have a square or rectangular shape, but may be provided so as to be quite generally n-polygonal or even have curved edge surfaces. From the embodiments shown, in particular with reference to
In the following, reference is made to yet another embodiment in accordance with
This is because, in the embodiment of