This application claims the benefit of German Patent Application No. 102022001407.6, filed on Apr. 25, 2022, the disclosure of which is hereby incorporated by reference in its entirety.
The invention relates to a combination antenna 0 for 5G mobile communications and satellite reception for vehicles, comprising, above a common horizontal electrically conductive base surface 6, at least one vertical broadband monopole antenna 1 for the 5G frequency range 6 having a ring-shaped satellite reception antenna 2 arranged concentrically thereto.
Locating satellite radio signals are as a rule transmitted using circularly polarized electromagnetic waves due to polarization rotations on the transmission path and are used in all known locating satellite navigation systems. Modern navigation systems provide for an evaluation of the simultaneously received radio signals of a plurality of locating satellite navigation systems, in particular for global availability in conjunction with high navigation accuracy in mobile navigation. Such systems that receive in combination are subsumed under the name GNSS global navigation satellite system and include known systems such as GPS Global Positioning System, GLONASS, Galileo and Beidou, etc. Locating satellite antennas for navigation on vehicles are as a rule configured on the electrically conductive outer skin of the vehicle body. In particular those antennas which are characterized by a low construction height in conjunction with a cost-effective manufacturing capability are suitable for setup on vehicles. For example, they in particular include the ring line radiator known from DE102009040910, configured as a resonant structure, and having a small construction volume that is in particular an absolute requirement for mobile applications. The antenna has a small base surface and is very low with a height of less than one tenth of the free-space wavelength.
A particular challenge for the locating satellite antennas for GNSS comprises the demand for a large frequency bandwidth that is, for example, predefined for GPS by the frequency band L1 having the center frequency 1575 MHz required bandwidth approximately 80 Hz and by the frequency band L2 having the center frequency 1227 MHz required bandwidth approximately 53 MHZ. Systems for the simultaneous evaluation of signal contents in the frequency bands L1=1535 MHz-1615 MHz and L2=1200 MHZ-1253 MHz place particularly high demands on the antennas. And this with a small available installation space, as is always the case, above all in vehicle construction.
The use of separate antennas located in close proximity to one another for the two frequency bands includes the problem of mutual electromagnetic coupling with the effect of influencing the directional diagrams and the polarization purity and in particular the cross-polarization. This results in the particular problem of designing a combination antenna 0 for mobile communications and locating satellite reception. Even with sufficient gain in the desired, typically right-hand circular polarization direction RHCP of the suppression, the opposite polarization direction—the cross-polarization LHCP—acquires crucial importance with respect to correct locating results. The accuracy of the locating result is thus particularly influenced by the ratio of the desired polarization direction to the cross-polarization of the locating satellite antenna, that is by the cross-polarization spacing.
The smallest interfering influences by the electromagnetic coupling of the mobile radio antenna on the locating satellite antenna leads to notable navigation errors. A particular challenge for the design of a combination antenna of this kind is in particular also posed by the requirement of the automotive industry for as small as possible an outline footprint of the combination antenna on the car body in conjunction with the requirement for a very small height of the combination antenna. As a basic requirement, the demand for a low-effort and thus economical manufacture of the combination antenna is of exceptional importance. The reception undisturbed by mutual electromagnetic coupling is likewise essential for the other satellite radio services broadcasting in the frequency range between 2.2 GHz and 2.5 GHz.
A combination antenna consisting of a satellite reception antenna and a mobile radio monopole designed from a conductive film is known from EP 2 784 874 A2. The mobile radio monopole specified there projects over the satellite antenna by an order of magnitude and is unsuitable due to the required small antenna height. Mass production is also more complex.
The present invention is therefore associated with the object of specifying a combination antenna that is economically less costly to manufacture, that is powerful for mobile communications in the 5G mobile communications frequency range at a very low overall height of between 1 cm and 5 cm and a small maximum footprint transverse extent of between 4 cm and 8 cm on the vehicle outer skin, and that also provides low-cross-modulation satellite navigation reception for obtaining accurate locating results or satellite reception true to the directional diagram for other satellite radio services in a vehicle.
This object is satisfied by the features of claim 1.
A combination antenna 0 for 5G mobile communications and satellite reception for vehicles is disclosed, comprising, above a common horizontal electrically conductive base surface 6 as ground, at least one vertical broadband monopole antenna 1 having the height hm for the 5G frequency range 6 and having a ring-shaped satellite reception antenna 2 arranged concentrically thereto, the combination antenna comprising at least one of the following features:
Advantageous embodiments of the invention are set forth in the dependent claims, in the description, and in the drawings.
The segment opening angle δ, 10 and the deflection angle θ, 7 can be matched to one another such that the angle ε, 10a remaining in the first section A1,15 between adjacent circular surface sides of the circular surface segments 5 disappears so that these sides merge into one another. An N-angled regular pyramid that forms the antenna connector 3a with its apex and that has a closed electrically conductive jacket surface, whose largest periphery Upyr is smaller than 0.8 *λmin, can thereby be formed.
The broadband monopole antenna 1 can
The central surface element A0,19 can be approximately circular within the first section A1,15 and its radius RA056 can be designed such that its periphery does not exceed 0.8*λmin so that the periphery of the conical body formed therefrom by mechanical deep-drawing does not exceed this value at any point.
The monopole antenna 1 formed as a folding body from the self-supporting electrically conductive film can be provided with embossed stiffening grooves 36 to stiffen the film and to facilitate its conical shape.
To produce the embossed stiffening grooves 36, raised embossing grooves for sheet metal stiffening 27 can be present at the jacket surface of the embossing cone 25 and at the horizontal embossing surface 26 of the embossing stamp upper part 20. The mutually complementary recessed counter-grooves for sheet metal stiffening 28 can be formed on the conical jacket surface of the funnel 24 and on the horizontal embossing surface 26 of the embossing stamp lower part 23.
To adapt the outline GD11a of the monopole roof capacity 4 to an approximately rectangular antenna cover in its second section A2,16, circular surface segments 5a cut in accordance with a section line course 35 can be designed.
The cutting of the circular surface segments 5 at the planar film cutout 29 can be performed such that a cutting tool 32 having a cutting tool upper part 33 at the embossing stamp upper part 20 and a cutting tool lower part 34 at the embossing stamp lower part 23 is present at the tool for the embossing deep-drawing process 22. Immediately following the embossing deep-drawing process 22 in time, the shortening of the second section A2,16 of the circular surface segments 5a to be cut can be given by the cutting movement of the two cutting tools against one another.
To design a cone with a closed conical jacket surface 37 and the monopole connector 3a at the cone apex at the nadir of the monopole antenna 1, the cone can be designed by deep-drawing the central surface element A0,19. At the center Z of the central surface element A0,19, downwardly deflectable fastening pinnacles 31 can be present for fastening the monopole antenna 1 on a circuit board 40.
To increase the size of the monopole roof capacity 4, the circular surface segment 5 can be extended beyond the end of the horizontally guided second section A2,16 by a third section A3,17 by selecting a correspondingly larger segment radius R,8, whereby the ends of the second sections A2,16 can describe a second bending line BL238 at which in each case the third section A3,17 can be bent slightly downwardly inclined.
At least one circular surface segment 5b can deviate from the shape of the other circular surface segments 5 such that, adjacent to the third section A3,17, a fourth section A4,18 is formed that can be kinked at the connection separating line as a third bending line BL339 extending toward the conductive base surface 6 and is conductively connected to the latter at its lower end.
By appropriately shaping the fourth section A4,18 in conjunction with the serial interconnection of a frequency-dependent network 41, the connection to the conductive base surface 6 can be designed as frequency-dependent such that its impedance at the lower frequency band end of mobile communications is suitably low, increasing with increasing frequency, whereby the fourth section A4,18 is without influence at higher frequencies.
An areal roof star structure 44 can be present, consisting of the same number N of star-shaped areal roof circular surface segments 45 that start from a common central connection surface 49 and whose surfaces in the region of the second section A2,16 and the third section A3,17 of the circular surface segments 5 are in each case designed congruently thereto and can be guided in parallel thereover for capacitive coupling. At least one of the areal roof circular surface segments 45b can deviate from the other roof circular surface segments 45 such that, instead of its radial end, a further section A3D 52 is formed adjacent thereto that is kinked there at the bending line BL2k, 48 extending toward the conductive base surface 6 and that is conductively connected to the latter at its lower end.
A thin-walled plastic cover 46 can be present which directly covers the second section A2,16 and the third section A3,17 of the circular surface segments 5 and at whose outer surface the roof circular surface segment 45 is applied for capacitive coupling to these sections.
To observe the condition BS<Bs max, a radial slot 53 can be present in each case at approximately the broadside center of the circular surface segment 5 to reduce the widening width of the circular surface segment 5 in order to observe the condition BS<Bs max.
To increase the size of the roof capacity, a respective elongate roof pinnacle 54 can be designed longitudinally in the first section A1,15 of each circular surface segment 5 by an elongate pinnacle cutout 55 for bending out at the first bending line BL1,14 such that the surface of the roof pinnacle 54 extends in parallel with the conductive base surface 6.
Every other one of the circular surface segments 5 can be designed in the azimuthal order as a circular surface segment 5c having a smaller segment radius Rc,8c for the additional formation of a shortened conical fan structure for supporting high mobile radio frequencies.
A plastic cover 46 whose inner shape includes a funnel shape and whose inner surface includes a reproduction of the course of the areal structures of the monopole antenna 1 can be present as a mechanical carrier of the areal structures of the monopole antenna 1. The areal structures can be coated with an MID-compatible lacquer and can be printed thereover with the areal structures of the monopole antenna 1 with the electrically conductive MID structures 61. However, the areal conductive structures can also be manufactured by a bonded electrically conductive film.
The combination antenna 1 can be manufactured in an advantageous embodiment in accordance with claim 1 having the following features. The monopole antenna 1 can be designed with respect to a minimum radiation coupling with the satellite reception antenna 2 for the free-space wavelength λmin=18.75 cm at the upper GNSS frequency band for the satellite reception antenna 2. There can be N=8 mutually identical circular surface segments 5. The monopole height hm can be selected as 0.1* λmin. The deflection angle θ, 7 can amount to θ=30° and the segment radius R, 8 can amount to R=0.17* λmin. The segment opening angle δ, 10 can amount to δ=15°. The conductive base surface 6 can be represented as an electrical circuit board 40.
The broadband monopole antenna (1) can be formed as a folding body and can be manufactured from a planar self-supporting electrically conductive film or from sheet metal.
The folding body can be formed from a circular sector cutout having the segment radius of the first section A1, 15 from the film.
To mark the N sectors, straight sector fold lines (63) can be provided, at each of which the film is kinked such that the closed jacket surface of an N-angled pyramid is formed.
The circular surface segments 5 can be designed with their second section A2, 16, their third section A3, 17 and with their fourth section A4,18 as laterally cut triangular surface segments 5d.
However, instead of the kink at straight sector fold lines (63), the circular sector cutout can be designed by mechanical shaping such that, for better impedance matching at the highest frequencies, instead of the elevation contour of a pyramid with straight sides, the elevation contour at the antenna connection point 3 starting with a larger opening angle and smoothly transitioning to a smaller opening angle is provided so that, for instance, the bulgy structure of a vase is reproduced.
The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein:
In the drawings, reference numbers may be reused to identify similar and/or identical elements.
The invention will be explained in more detail in the following with reference to embodiments. The associated Figures show in detail:
a)
A combination antenna 0 consisting of a monopole antenna 1 having a satellite reception antenna 2 placed concentrically thereto as a ring line radiator having a closed ring line 2a with the ring line height hr for the current distribution of a propagating line wave above the electrically conductive base surface 6. The satellite reception antenna 2 is designed for satellite navigation reception in the GNSS frequency range 1200.5 MHz to 1616 MHz or for satellite frequency ranges between 2200 MHz to 2500 MHz. The height hr of the satellite reception antenna 2 is selected in the range 0.5 cm<hr<2 cm. The satellite antenna connection can advantageously take place at at least one of its vertical radiators.
The monopole antenna 1 in accordance with the invention is designed as a vertical radiator having a roof capacity for mobile communications in the 5G frequency range between 617 MHz and 5.9 GHZ. In the example, the radiator is formed as an N=10-leaf fan-shaped palm-like structure of mutually identical circular surface segments 5 composed of an electrically conductive film that are azimuthally uniformly distributed and that are connected at their lower tips. Due to the connected tips, the monopole connector 3a and, together with the ground connector 3b, the antenna connection point 3 of the monopole antenna 1 are formed at the center ZL.
The description of the fan-shaped, palm-like structure can equivalently also take place based on triangular surface segments 5, instead of by the circular surface segments 5, by analogously replacing the segment radius R,8 with the corresponding triangle height. By designing the individual leaves as circular surface segments 5 or triangular surface segments, it is ensured that the monopole antenna 1 has, at the monopole connector 3a, a fan-shaped pyramid apex or a cone apex that enables the impedance matching with the continuing circuit for the upper frequencies of the 5G frequency range. If N circular surface segments 5 are formed, the angle ε, 10a remaining between adjacent circular surface sides of the circular surface segments 5 results in the region of the first section A1,15 of a circular surface segment 5 at a sector angle of 2π/N and in the combination of the segment opening angle δ, 10 with the deflection angle θ, 7.
To form an areal monopole roof capacity 4, each circular surface segment 5 is bent radially outwardly in the second section A2,16 with respect to the central line ZL along a first bending line BL1,14 located at the monopole height 1 cm<hm<5 cm above the conductive base surface such that the circular surface segment 5 is guided in this second section A2,16 substantially in parallel with the base surface 6. The radial length of the second section A2,16 is selected via the segment radius R,8, the length of the resulting first section A1,15 and the deflection angle θ,10 such that the outline GS,11 of the satellite reception antenna 2 is at least completely covered by the outline GD,11a of the monopole roof capacity 4.
To avoid the impairment of the satellite reception by electromagnetic coupling of the satellite reception antenna 2 with the monopole antenna 1, the condition is to be observed—in accordance with the invention—that the width of the circular surface segments BS,9 is to be selected smaller than ⅛ of the shortest free-space wavelength of the received satellite signal. In this respect, it should in particular be ensured that in the region of the radial ends of the circular surface segments 5 their width BS,9 does not exceed the predefined value—in accordance with the invention—of ⅛ of the free-space wavelength λmin and circular surface segments 5 in this region are cut accordingly in their width to observe these conditions. Due to the small width of the second section A2,16 of the circular surface segments 5, no azimuthally directed currents caused by the radiation of the satellite antenna 2 can form that, on the other hand, affect the satellite antenna 2 and impair its function with respect to locating results or the radiation directional diagram. Even though the monopole antenna 1 completely covers the satellite reception antenna 2, the cover designed in accordance with the invention is practically transparent with respect to the radiation of the satellite reception antenna 2.
In the interest of forming a monopole roof capacity 4 that is as large as possible, the remaining angle ε, 10a should be selected as small as possible, wherein, on the other hand, the condition with respect to the width BS,9<0.125*λmin is to be observed, however.
In a particularly advantageous embodiment of the invention, the segment opening angle δ, 10 is selected such that the full sector angle 2π/N is used and a closed cone jacket or pyramid jacket with the maximum height hm of the monopole antenna 1 is formed in the first section A1,15 of the circular surface segments 5. In accordance with the invention, the condition for the periphery Upyr<0.8*λmin of said closed cone jacket or pyramid jacket additionally has to be observed in any case.
In a particularly advantageous embodiment of the invention, for a sector number N, the segment opening angle δ, 10 and the deflection angle θ, 7 can be selected to match one another such that the remaining angle ε, 10a disappears and adjacent circular surface sides contact one another so that a closed jacket surface of a cone or a pyramid is formed. Thus, in the lower region of the monopole antenna 1, the inductive and capacitive effects are balanced at high frequencies and an almost frequency-independent wave impedance—dependent on the segment opening angle δ, 10 and the deflection angle θ, 7 of the cone jacket or pyramid jacket—is formed. The height of the cone or of the pyramid can reach at most the height hm of the monopole antenna 2. In this case, to avoid the impairment of the satellite reception by electromagnetic coupling of the satellite reception antenna 2, the condition is to be observed that the periphery Upyr of the cone or of the pyramid does not exceed the value 0.8*λmin at any point, in particular at its upper end. In practice, preferred values for the height of the cone or of the pyramid are between 0.2*hm to 0.7*hm.
b)
Available space for the antenna in the form of a cuboid of interrupted lines with a square base surface of the available transverse extent and the available height hm—and a combination antenna 0 in accordance with the invention inscribed on said cuboid for consideration of the antenna potential.
a)
A circular sectional view or a cutaway view for a monopole antenna 1 in the combination antenna 0 in accordance with the invention. The design of the monopole antenna 1 is based on a planar, rigid but flexible metal film or plastic film with a metallic coating shown here by way of example, from which the circular surface segments 5 are cut out that are connected at their tips via a central surface element A0,19. The example shows N sectors with the angle 2π/N, each having a circular surface segment 5, the segment radius R,8 and its segment opening angle δ, 10 that is correspondingly smaller than 2π/N. Circular surface segments 5 uniformly distributed over the azimuth—around the central line ZL perpendicular at the circle center—are formed from the circular cutout by a film cutout N. The dotted circle with the radius RBL, 13 describes the first bending line BL1,14 that divides the segment radius R, 8 into a first section A1,15 and a second section A2,16. For the second section A2,16, the condition for the running width
B(r)/min=2*r*tan(/2)/min<0.125
is to be observed in accordance with the invention for the running radius r as the distance from the center.
b)
Elevation of the folded monopole antenna 1 in accordance with the invention, as at a). The angle bisectors WH 12 of the circular surface segments 5 in FIG. a) are rotated about their tips such that they are angled out in their first section A1,15 with respect to the central line ZL by the deflection angle θ, 7. In its second section A2,16, each circular surface segment 5 is modified such that it is bent radially outwardly along the first bending line BL1,14 with the radius RBL,13 in FIG. a) at the monopole height hm above the conductive base surface 6, whereby the radiating monopole roof capacity 4 is formed over all the second sections A2,16 of the circular surface segments 5. The covering, as required by the invention, of the outline GS,11 of the satellite reception antenna 2 by the outline GD,11a of the monopole roof capacity 4 is achieved at a predefined deflection angle θ, 7 and a predefined height hm of the monopole antenna 1 via the selection of the segment radius R,8t.
c)
If, for a number N of the circular surface segments, the segment opening angle δ, 10 and the deflection angle θ, 7 are selected such that the following relationship
is satisfied, there is no contact between adjacent triangular sides of the circular surface segments 5 and a separation angle ε, 10a remains between them. In this case, after the folding, a monopole antenna 1, as in
The Figure shows a monopole antenna 1 in accordance with the invention in perspective, in which, for a number N of the circular surface segments 5, the segment opening angle δ, 10 and the deflection angle θ, 7 are selected such that in the first section A1,15 of the circular surface segments 5 the sides of adjacent circular surface segments 5 just contact one another so that in this section the closed pyramid jacket of an upside-down regular pyramid—in the specific example with the monopole height hm—with N side surfaces is formed. In this case, the two sides of the inequality (1) are of equal size and the following relationship exists between the segment opening angle δ, 10 and the deflection angle θ 7 for a selected number of circular surface segments N:
In this example, to design the electrically closed pyramid jacket with the height hm, the sides that contact one another are conductively connected to one another by, for example, geometrically shaping and mechanically deep-drawing the electrically conductive film such that the pyramid jacket is given.
The description by circular surface segments 5 is here carried out by the functionally equivalent description by triangular surface segments 5d, wherein the segment radius R, 8 is replaced by the triangular segment height hs, 8d that only insignificantly deviates therefrom.
To avoid the interference of the satellite antenna 2 by electromagnetic coupling with the closed pyramid jacket, it is required in accordance with the present invention that the periphery of the pyramid jacket Upyr is not larger than 0.8*λmin at any point, with the largest periphery Upyr occurring at the monopole height hm. Thus, in accordance with the invention, the following relationship is required to be observed.
This condition can be observed by selecting a correspondingly smaller height of the pyramid jacket than hm.
d)
A plan view of the exemplary antenna with the height of the pyramid jacket hm at c) with the bent-out second sections A2,16 of the circular surface segments 5 or the triangular surface segments 5d for designing the largest possible monopole roof capacity 4 and the antenna with its pyramid as the trunk and its sections A2,16 of the circular surface segments 5 as the leaves resembling a palm tree.
In accordance with the invention, the azimuthal width BS, 9 of the circular surface segments 5 of the monopole antenna 1 is to be selected smaller than ⅛ of the free-space wavelength λmin of the highest frequency of the satellite band. Due to the triangular surfaces opening in the radial direction with the segment opening angle δ, 10, this rule in particular applies to the end of the covering of the satellite antenna 2 by the monopole roof capacity 4, i.e. at the outline edge GD 11 for this example.
If the inequality (3) cannot be observed, provision is made in accordance with the invention that the triangular surface segments 5 are, in their sections A2,16, each provided with radial slots 53, as explained in connection with
From the structure of the monopole antenna 1 that is predefined in accordance with the invention, a remaining angle ε1, 10b generally results in each case between the adjacent circular surface sides of the circular surface segments 5 bent out in the second section A2,16. An overlapping of an adjacent circular surface segment 5 and a resulting harmful coupling of the monopole antenna 1 with the satellite antenna 2 is advantageously not given. With circular surface segments 5 not cut in their width, the remaining angle ε1, 10b results as follows for the monopole antenna 1 with a closed N-angled pyramid—i.e. while observing the relationship (1) or (2):
e)
The following representations in FIGS. e) to h) refer by way of example to a combination antenna 0 with an outline GD, 11a of 3 cm and a height hm of the monopole antenna of 2 cm. In accordance with the relationship (1) or (2), a closed pyramid jacket with the height hm of the monopole antenna 1 is formed. The free-space wavelength of the highest frequency of the satellite band amounts to λmin=18.5 cm by way of example.
A representation of the relationship between the deflection angle θ,7 and the segment opening angle δ,10 of the circular surface segments 5 of the electrically conductive closed pyramid for a different number N of the circular surface segments or triangular surface segments in accordance with the above-mentioned relationships (1) and (2) respectively. The preferred range for the deflection angle θ<60° and for the segment opening angle δ<60° is indicated by the chain-dotted lines.
f)
A representation of the relationship between the maximum width of the circular surface segments 5 (BS/λmin) at the radial end of the outline GD, 11a, said maximum width being related to the minimum free-space wavelength λmin at the maximum frequency of the satellite frequency band, and the deflection angle θ, 7 for several numbers N of circular surface segments. In accordance with the above-mentioned relationship (4) of the invention, BS/λmin<0.125 is required. From the diagram, it can be seen that when the dash-dotted line is exceeded at BS/λmin=0.125, the circular surface segments 5 are designed in accordance with the laterally cut triangular surface segment 5d or have a radial slot 53 at their radial end—as described in connection with
g)
Corresponding to the requirement BS/λmin<0.125, the maximum periphery Upyr of the closed pyramid jacket or cone jacket of the monopole antenna 1, which maximum periphery is related to λmin and occurs at the height hm, is also required—in accordance with the present invention—to be smaller than 0.8. The Upyr/λmin condition is given in the above-mentioned relationship (3) in dependence on the monopole height hm related to λmin, the deflection angle θ, 7, the segment opening angle δ, 10, and the number N of circular surface segments 5, i.e. the sectors. The observation of the condition (1) or (2) as a prerequisite for the closed pyramid jacket or cone jacket is assumed for this purpose. The curve developments shown in particular do not show a degradation of the properties of the satellite antenna 2, due to the radiation coupling with the closed pyramid jacket or cone jacket, for deflection angles θ, 7 of less than 45° and for a larger fanning out of the monopole roof capacity 4 of N>4.
h)
A representation of the remaining angle ε1, 10b between the adjacent circular surface sides of the circular surface segments 5 bent out in the second section A2,16, as shown in
To increase the size of the monopole roof capacity 4, the circular surface segment 5 is extended beyond the end of the horizontally guided second section A2,16 by a third section A3,17 by selecting a correspondingly larger segment radius R,8, whereby the ends of the second sections A2,16 describe a second bending line BL238 at which in each case the third section A3,17 is bent slightly downwardly inclined in adaptation to the antenna cover.
For support in one of the circular surface segments 5, a fourth section A4,18 is formed adjacent to the third section A3,17, said fourth section A4,18 being bent at the connection separating line as a third bending line BL339 extending toward the conductive base surface 6 and being conductively connected to the latter at its lower end.
A combination antenna 0 in accordance with the invention as in
In deviation from the other circular surface segments 5, a fourth section A4,18 is formed adjacent to the third section A3,17, said fourth section A4,18 being bent at the connection separating line as a third bending line BL339 extending toward the conductive base surface 6 and being conductively connected to the latter at its lower end. An improvement with respect to the possible impedance matching at the lower 5G frequency band end, and thus an increase in the antenna potential, is associated with this measure.
A combination antenna 0 in accordance with the invention as in
The satellite antenna 2 with its ring line 2a and the vertical radiators is connected and energized via their connection points 43 on the circuit board.
a)
Combination antennas 0 in accordance with the invention as in
b)
A longitudinal section through an antenna as at a) with a side view of the third roof section A3D, 52. For a capacitive coupling of the roof star structure 44, the plastic cover 46 is thin-walled, but also provides the mechanical stability of the design. The electrical contact of the third roof section A3D, 52 with the conductive base surface 6 takes place at the mechanical connection of the plastic cover 46 to the conductive base surface 6 or to the electrical circuit board 40.
To manufacture the monopole antenna 1 for the combination antenna 0 in accordance with the invention, the following steps are provided for a rotationally symmetrical embossing deep-drawing process 22:
A tool for a rotationally symmetrical embossing deep-drawing process 22 as in
A combination antenna 0, as in
A tool for the embossing deep-drawing process 22 combined with a cutting tool 32 for cutting the planar cut film cutout, as described in
In the time following the embossing deep-drawing process 22, the shortening of the second section A2,16 of the circular surface segments 5a to be cut can take place by the cutting movement of the two cutting tools against one another.
At the center of the film cutout 29, in order to form a cone with a closed jacket surface 37 and the monopole connector 3a in the first section A1,15 of the circular surface segments 5, a central surface element A0,19 is marked whose radius RA0 is at most equal to the first section A1,15. The cone is designed by deep-drawing the central surface element A0,19 by means of an embossing deep-drawing process 22—as described in
In addition, the embossing/deep-drawing process advantageously allows stiffening grooves 36 to be formed all around to stiffen the ramifications in the structure and to facilitate the conical shape. At the center of the central surface element A0,19, downwardly deflectable fastening pinnacles 31 are provided for fastening the monopole antenna 1 on a circuit board 40. The pinnacles are bent downwardly to jointly form, via cuts through the circuit board 40, the monopole connector 3a and to fix the monopole antenna 1.
In adaptation to a more rectangular antenna cover in the form of a plastic cover 46, provision is made to cut the second sections A2,16 of the circular surface segments 5 accordingly and to bend them slightly downwardly inclined along the first bending line BL1,14.
b)
A cross-section of a combination antenna 0 above an electrical circuit board 40 below a plastic cover 46. Due to the accurate fit of the plastic cover 46 with respect to the structure of the monopole antenna 1 in connection with transverse struts 61 on the plastic cover 46, the monopole antenna is held in a mechanically stable manner.
c)
Semi-manufactured and completely manufactured parts of the monopole antenna 1 can be stored stacked on top of one another in mass production—as shown—without getting caught in one another. This possibility is very advantageous in mass production, providing simple intermediate storage options and time savings.
a:
A film cutout 29 as in
b:
A film cutout 29 as in
Along the bending line BL 1,14, the second section A2,16 is bent over, as in the other Figures, such that its surface is guided in parallel with the conductive base plane 6 to form the monopole roof capacity 4.
The roof pinnacles 54 are each formed longitudinally in the first section A1,15 of the circular surface segment 5 by an elongate pinnacle section 55. After forming the partly fan-shaped cone jacket from the film cutout 29, an increase in the size of the roof capacity 4 of the monopole antenna 1 is achieved in that the roof pinnacle 54 of each circular surface segment 5 is bent along the first bending line BL1,14 toward the central line such that the surface of the roof pinnacle 54 extends above the opening of the cone in parallel with the conductive base 6.
a)
A film cutout 29 as in
b)
A combination antenna 0 for the 5G frequency range comprising
a)
A combination antenna 0 in accordance with the invention with a plastic cover 46 as a mechanical carrier of the areal structures of the monopole antenna 1. The inner shape of the plastic cover 46 includes a funnel shape and its inner surface includes a reproduction of the course of the areal structures in accordance with
b)
An outer view of the three-dimensional plastic cover 46 as in FIG. a) with areal MID structures 61 of the monopole antenna 1 printed on the inner side of a thin-walled cover. The printed MID structures are drawn on the outer side by reason of the clearer representation.
c)
A combination antenna 0 as in
A sectional view or a cutaway view for a monopole antenna 1 in the combination antenna 0 in accordance with the invention. The design of the monopole antenna 1 is based on a planar, rigid but flexible metal film or plastic film with a metallic coating shown here by way of example. In deviation from the circular sectional view in
The advantages and the mode of operation of the invention are further explained below.
It is known from the theory of electrically small antennas that the potential of an antenna is to be considered as the ratio of Q=real part/imaginary part of the antenna impedance. For an antenna that is inscribed on a sphere having a radius a, the theoretical maximum of this potential with respect to the free-space wavelength of the radiation is given as the relationship Q=2 πa/λ{circumflex over ( )}3. The maximum achievable potential grows with the third power of the spatial dimension related to the free-space wavelength and is thus unreasonably small. However, this theoretical maximum can furthermore only be reached when the antenna, with its structures, completely fills the available space in the sphere and the structural elements constructively contribute to the total radiation in their radiation effect.
The particular challenge in connection with the present invention is the predefined smallness of the cuboid on which the combination antenna for the 5G frequency range is to be inscribed compared to the largest wavelength at the lower limit of the 5G frequency range from fu=617 MHz to fo=5.9 GHZ. For example, if the height hm=3 cm and the footprint transverse extent=6 cm are predefined for the cuboid, the estimated radius a of a comparable sphere, on which the combination antenna is to be inscribed, amounts to approximately a=6.5 cm. In accordance with the relationship given above, the extreme ratio of the free-space wavelength λu=approx. 50 cm at the frequency fu to the sphere radius leads, due to the third power of the mismatch of a/λu, to a very small antenna potential of Q=0.014, which, however, is furthermore only attainable with theoretically optimally designed antenna structures in this space.
It is therefore decisive that the combination antenna 0 in accordance with the invention with its structure—as shown below—practically fulfills this condition in a particular manner and achieves—under the naturally predefined restriction—an optimum antenna potential. When considering the combination antenna 0 in accordance with the invention, as in
Now, the particular advantage of the combination antenna 0 in accordance with the invention precisely also consists in the fact that the advantage is not only limited to the optimum design of the monopole antenna 1 with respect to its potential, but it is additionally possible, by the special design of the monopole antenna 1 in accordance with the invention, to place the satellite reception antenna 2 under its roof and to avoid the radiation shadowing through the special shape of the roof capacity. Figuratively speaking, the radiation of the satellite reception antenna 2 can penetrate the roof of the monopole antenna 0 that appears transparent to the satellite reception antenna 2.
A further advantage of the combination antenna 0 in accordance with the invention, which is decisive for mass production in large quantities for the vehicle industry, is the comparatively very simple manufacturing process of the monopole antenna 1 so that an economical manufacture is possible. If the monopole antenna 1 is designed from a self-supporting sheet metal film, it can also be manufactured, taking account of its complex shape, by stamping and bending processes to be performed in a simple manner. Even the serial intermediate storage of half-finished antenna molded parts can take place easily and without a snagging of the parts. The combination of the ring-shaped satellite reception antenna 2 with the monopole antenna 1 within the outline of the monopole antenna 1 can, due to the special coupling-free design of the monopole antenna 1 with the satellite reception antenna 2, advantageously take place without changing it.
Number | Date | Country | Kind |
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102022001407.6 | Apr 2022 | DE | national |