EP2225795A1

EP2225795A1 - Antenna field for a motor vehicle disk

Info

Publication number: EP2225795A1
Application number: EP09728246A
Authority: EP
Inventors: Thomas Lankes; Anton Ilsanker; Gerald Schillmeier; Bülent SOLAN
Original assignee: Kathrein Werke KG
Current assignee: Kathrein SE
Priority date: 2008-04-03
Filing date: 2009-03-26
Publication date: 2010-09-08
Anticipated expiration: 2029-03-26
Also published as: DE102008017052B4; CN101953020B; EP2225795B1; ATE511223T1; KR101578844B1; JP2011517197A; WO2009121521A1; US20100321258A1; KR20100133360A; DE102008017052A1; JP5422642B2; CN101953020A; ES2367098T3

Abstract

The invention relates to an improved antenna field, characterized by the following features: at least one capacitance (19') is switched between one of the two bus bars (11a, 11b) and at least one center section (9c) of the heating wire (9a, 9b, 9c) formed between 20% and 80% of the total length of the heating wire (9; 9a, 9b, 9c), and/or at least one capacitance (19") is switched between at least two center sections (9c, 9'c) of the heating wires (9; 9a, 9b, 9c, 9'a, 9'b, 9'c) formed between 20% and 80% of the total length of two heating wires (9; 9a, 9b, 9c; 9'a, 9'b, 9'c), and the at least one capacitance (19', 19") is greater than 50 pF.

Description

Antenna field for a motor vehicle windshield

The invention relates to an antenna field for a motor vehicle window, in particular a motor vehicle rear window according to the preamble of claim 1.

It is well known that, for example, a heating field provided in the rear window of a passenger car can also be used as an antenna field. Usually, a busbar is provided in the rectangular or trapezoidally shaped rear window on the left and right sides, between which the individual heating wires run parallel to each other. Each of the two busbars is connected to the pole of a vehicle battery.

It is possible to provide transverse secondary conductors on equipotential lines, which are basically suitable for improving the reception qualities of such a rear window antenna. Since these secondary conductors extend on the aforementioned equipotential lines, it is essentially ensured that no cross-currents flow here between the heating wires. Such, serving as an antenna field rear window heater may comprise a heating field or more heating fields. It is also possible that in addition to the heating field, a separate or additional antenna array is provided. Even if only one antenna field completely separate from the heating field were provided in a pane, in particular in the rear window of the motor vehicle, the adjacent heating field would have repercussions on the antenna field, ie ultimately influencing the reception quality of the antenna field.

The housed in the rear windows antenna and / or heating panels are often used for radio reception, especially the reception of radio and TV programs in the LW, MW, KW, FM and / or microwave range.

Corresponding heating and / or antenna fields have become known, for example, from DE 100 33 336 A1, DE 43 21 805 A1, EP 1 366 540 B1 and DE 43 23 239 C2. It can also be seen, for example, from the above-mentioned DE 100 33 336 A1 that, in an embodiment variant according to FIG. 6, a capacitance is additionally connected between the two busbars.

Finally, from DE 195 41 083 Al a glass antenna for a rear window as known, with the heater also serves as an antenna system. According to this prior publication is proposed as a solution to create a glass antenna, which ensures a better view of the driver to the rear. For this purpose, the antenna itself comprises a multiplicity of heating wires, which are oriented essentially in the horizontal direction and are arranged parallel to one another with an offset from one another run a right busbar. In the middle, a conductor wire is provided transversely extending thereon on a middle equipotential line, which connects the multiplicity of transverse heating wires electrically-galvanically. Finally, another shorter conductor wire is arranged parallel to the top heating wire, which results in a capacitive coupling to the adjacent heating wire. The antenna pickup then takes place via this conductor wire. According to this prior publication, the capacity should be less than 40 pF, since otherwise it would be nonsensical to increase the coupling capacity beyond 40 pF.

The object of the present invention is to provide an improved antenna field integrated in a pane, which completely or partially consists of or comprises the heating field and / or is provided next to the heating field as a separate sole or additional antenna field.

The object is achieved according to the invention in accordance with the features specified in claim 1. Advantageous embodiments of the invention are specified in the subclaims.

In the context of the invention, appropriate adaptation measures for improving the reception quality of an antenna field integrated in the pane are now provided on the basis of completely novel design considerations with respect to the heating field. However, the advantages according to the invention arise not only when the entire heating field is also used as an antenna field, but above all even if the heating field is split into several heating fields, individual heating fields, for example, serve as an antenna field or even one of the one or more Heating fields remote pure antenna field is provided.

In the present invention, it is assumed that a busbar structure, in which the two bus bars are preferably provided wholly or substantially on one side, usually on the lower usually more or less horizontally extending window side. It should also be possible within the scope of the invention that the two busbars are wholly or substantially not provided on opposite sides of a window or a window, so for example wholly or partially on the underside of a window and wholly or partly on a right or left side of the Automobile window.

In particular, in such an embodiment (but also in conventional embodiments with provided in the motor vehicle windows on opposite sides busbars) an improvement of the antenna property, in particular the reception quality is realized in that, for example, a busbar and a rather middle section of a heating wire ( wherein the average distance between 20% and 80% of the total length of a corresponding heating wire should be) is connected by means of a capacitor. Alternatively and additionally, however, such a capacitance can also be connected between two heating wires connected to the respective busbars, namely preferably between a middle section of two corresponding heating wires, wherein the middle section of the two heating wires is again preferably between 20% and 80% of the total length of the respective Heating wire should lie. In this case, the mentioned capacitances, ie the respectively at least one capacitance, should be connected and / or provided as far as possible in a direct connection between the relevant connection points to the busbar sections and / or the preferably central sections of the mentioned heating wires, as well as possibly other ones besides the capacitance Components such as an inductor may be provided to produce a series resonant circuit.

Preferably, this capacity is still provided at the level of the disc material. Preferably, the capacity is realized in the form of a discrete or concentrated component.

The at least one capacitance can be soldered via wires, for example, as an electrolytic capacitor (ELKO capacitance). Also suitable are ceramic capacitors, flexible printed circuit boards etc.

A favorable order of magnitude for the capacity is, for example, between 50 pF and 10 μF. Frequently, values above 0.1 nF or above 0.1 μF and in particular above 0.5 nF or above 0.5 μF will suffice for FM reception.

Basically, the capacitive coupling can also be realized by a plurality of capacitors connected in series or, for example, by a series resonant circuit of capacitor and coil etc. In this case, a center tap between two series-connected capacitors would be considered, the direct or eg via a throttle to ground is laid (in particular on body mass). A connection of several capacities via Mas- However, this would adversely affect the antenna characteristics and reception qualities.

In summary, it can be stated that antenna properties can be realized by the solution according to the invention, which have a lower frequency dependence, i.e. a lower frequency dependence, than a comparable antenna and heating field. So have a larger bandwidth. In addition, a suppression or displacement of the resonance behavior of the heating conductors for high-frequency signals can be realized within the scope of the invention.

The invention is particularly suitable for new geometries for heating panels. The invention therefore has particular advantages when heating fields are used which, for example, comprise trapezoidal heating elements spaced apart from each other or even formed according to concentric circles or ovals, etc. Since the heating conductors should in principle have a similar overall length (in order to produce an approximately comparable thickness of the heating conductors-to produce comparable total resistances per heating wire), in the case of a heating field formed from concentric circles in a comparable arrangement, it can be thought of as lying inside Heat conductor to connect at one end to produce a total of longer heating conductors. In this case, at least one capacitance, which contribute to similar improvements of the antenna field, can also be connected directly to one of the busbars and / or also between the heat conductors with each other or between a heat conductor and a busbar, as described above with reference to FIGS between the busbars switched capacity was explained. This is especially true of Meaning, if due to the interconnection of conductors for the production of heaters with greater overall length, no secondary conductors lying on equipotential surfaces can be switched.

Further advantages, details and features of the invention will become apparent from the embodiment illustrated with reference to drawings. In detail:

Figure 1: a first schematic, not belonging to the invention embodiment of a heating and antenna field, which is integrated in a disc of a motor vehicle;

FIG. 2 shows a modified exemplary embodiment according to the invention with two interconnected heating conductors in the innermost one;

FIG. 3 shows a further modified embodiment according to the invention, in which the busbars are provided on two non-opposite sides of a rear window; and

Figure 4: a slightly modified to Figure 2, further inventive Ausführungsbei- game with a capacitive connection between two heating conductors, which are each connected to the respective two bus bars. FIG. 1 shows a schematic front view of a pane 1, for example of a motor vehicle, in particular a rear window I ¹ , which schematically shows an upper boundary or boundary edge Ia, a lower boundary or boundary edge Ib and a left and a right boundary or boundary edge Ic or Ic Id. In practice, these boundary edges are not in pairs parallel to each other, but curved, more approximate to a trapezoidal shape or the like, since the windows are usually wider from top to bottom. Restrictions on the shape of the discs are so far not given, so that even any curved boundary lines are conceivable.

In the disk thus formed, a heating field 7 is integrated, which comprises a plurality of externally or internally extending in the disk conductors 9, in the embodiment shown in Figure 1 between a first and a second busbar 11, in the illustrated embodiment between the left busbar IIa and extend to a subsequent right busbar IIb. The heating field 7 forms an antenna field 5 in the exemplary embodiment according to FIG.

Each busbar is associated with a supply or connecting line 13a or 13b, wherein, for example, the connection line 13a is connected to the battery supply network on board the motor vehicle (usually the positive pole) and the other supply line 13b to the other pole, for example the body ground. In the connection or

Feed lines are usually blocking circuits to prevent flow of high-frequency currents. - S -

In the embodiment shown, the individual conductors 9 are provided extending in a more or less equidistant arrangement between the busbars due to the selected geometry for the heating field, with an always constant distance is not mandatory or at least not over the entire length of the individual heating ladder is necessary , In this case, the geometry is selected so that the two busbars IIa and IIb are provided on one side of the disk, in the exemplary embodiment shown in the region of the lower boundary Ib, wherein the busbars are arranged symmetrically to a central plane of symmetry 14. The heating conductors 9 are in this case e.g. partially circular or even semi-circular in the embodiment shown, but may also have other waveforms, here semi-oval, etc., wherein the radii or diameter from inside to outside are increasingly larger, so that the length of the individual heating increases from the inside out.

Furthermore, a secondary line 15 is provided, which connects the outer eight heating conductors in the middle and serves as Antennenabgriffsleitung 17. Such a secondary line 15 is galvanically considered on equipotential surfaces, whereby the DC distribution of the heating field is not changed. Nevertheless, this improves the antenna receiving characteristic, which is well known. Furthermore, two further antenna tapping lines 117 are connected at the respectively opposite outer ends of the two busbars IIa and IIb, but they may also be connected to the busbar or the heating field elsewhere, and may even coincide with the feeder lines 13a or 13b. Thus, in the exemplary embodiment shown, two heating field connections 13a and 13b and three antenna tapping connections 17, 117 are provided. However, the number of connections can also be different, in particular if, for example, split-up heating fields are provided which not only run between two busbars (for example, known from DE 100 33 336 A1 or DE 43 21 805 A1).

In the embodiment shown, the two bus bars 11 are further provided lying in a horizontal line, in axial extension to each other (even if the Scheibendraufsieht can be curved), wherein the two busbars at its inner end 11 'a and 11' b on a interconnected capacitance 19 are interconnected.

There is thus a direct connection between the two busbars IIa and IIb with the interposition of a capacitor. This capacity is arranged so that virtually the shortest distance between the two busbars is bridged. The capacity should therefore preferably still be provided in the amount of the disc 1, even if, of course, a wiring from the disc area away and back to the other busbar back to the disc area back. However, with an increase in the capacitance over the connecting path 21, a certain deterioration in the antenna characteristic can be detected.

The distance space 121 formed between the two ends 11 'a and 11' b of the two busbars IIa and IIb is small in size and has a length between them two busbars, which preferably corresponds to less than five times, four times, in particular less than three or even two times the distance between two adjacent heating conductors.

The capacitance can consist of one or more discrete or concentrated components, preferably of a capacitor 119 connected by wiring. Preferably, this can be designed as an SMD component, although a capacitor with at least two capacitor surfaces or foils applied parallel to the disk surface plane-parallel capacitance surfaces and an interposed insulator surface are conceivable. The capacitance may also consist of an electrolytic capacitor with corresponding wiring, ceramic capacitors, flexible printed circuit boards, etc. There are no restrictions on specific capacitor types or capacitor types.

The capacities in question should preferably be between 50 pF and 10 μF, in particular in a range of greater than 0.1 nF or 0.1 μF and in particular greater than 0.5 nF or greater than 0.5 μF.

Thus, if possible, the capacities should be greater than 50 pF, 0.1 nF, 0.25 nF, 0.5 nF, 1 nF or even greater than 3 nF or 5 nF or greater than 0.1 μF, 0, 25 μF, 0.5 μF, 1 μF or even greater than 3 μF or even 5 μF. On the other hand, capacitance values less than 10 μF, less than 5 μF, less than 1 μF and possibly even less than 0.5 μF make sense and are possible for certain applications. Such a trained antenna is particularly suitable in the frequency range of, for example, 125 KHz to 1.6 GHz. In the broadcasting sector, the antenna is particularly suitable for frequency ranges from 70 MHz to 900 MHz.

Since, in the embodiment shown in FIG. 1, the inner heating conductors are much shorter than the outer ones, the outer, ie. longer heating conductor to be designed to be increasingly thicker to produce comparable heating power per heat conductor.

In order to provide a compensation with respect to the length of the heating conductors, ie to avoid strong differences in the Heizleiterdicken is provided in the embodiment shown in Figure 2 that, for example, the two heating conductors lying on the inside are interconnected. In the exemplary embodiment according to FIG. 2, it is thus provided that the two heating conductors 9a and 9b located to the inside are not connected to the collector bus IIb lying to the right but are connected to one another via a transverse connection 9c, ie via a transverse connection 9c in the embodiment shown at a small distance parallel to the busbar IIb runs. The connection points 109 'and 109 "of these two heating conductors to the busbars IIa and IIb are provided in the embodiment shown directly on the two facing each other ends 11' a and 11 'b of the two busbars IIa and IIb, which are formed differently long in this geometry This results in a heating conductor consisting of the heating conductor 9a, the connection or the so-called connecting section 9c and the further return heating conductor 9b, this heating conductor being like the capacitance mentioned above. 19 at the two closely spaced end portions 11 'a and 11' b of the busbars IIa and IIb is connected.

In this case, as a further measure, whereby the antenna characteristic is improved, a further capacitor 19 'is provided, which is now connected and / or formed between the connection 9c of the two interconnected heating conductors 9a and 9b on the one hand and on the adjacent busbar IIb to the other is. Again, a concentrated or discrete component in the form of a capacitor 119 'is preferably used with corresponding connection points or corresponding wiring.

It is shown in the drawing that the additional capacitance 19 ', preferably in the form of an additional capacitor 119', is connected between the one bus bar IIb and a rather middle section of the continuous heating line, wherein the middle section 9c, the two heating wires 9a and 9b connects, preferably between 20% and 80% of the total length of the heating wire formed from the heating wires 9a, 9b and the connecting line 9c, ie in the range of one connecting end calculated above 20%, in particular above 30%, 40%, 50% and of the second connection end calculated just below 80%, in particular below 70%, 60% or 50%. In the embodiment shown, the connecting portion 9c is in a range of 40% to 50% of the total length of this heating wire formed from the heating wires 9a, 9b and the connecting portion 9c.

The illustrated example with the compound 9c can also find application for other heating and is not limited only to the two innermost heating conductors.

FIG. 2 also shows that in addition to the heating field switched as an antenna field, an additional second separate antenna field 5 'with antenna conductors 105 is provided, which has, for example, a further connection 105a for connection to a downstream receiving unit (for example car radio).

Due to the specific arrangement of the antenna and heating field according to the embodiment of Figure 2 is also apparent that it may be appropriate to design the busbars of different lengths, so that the innermost heating conductor 9a not over a certain distance to the right second collection rail IIb must be returned. Here, however, any modifications are possible and conceivable.

It is also mentioned that, under certain circumstances, a plurality of capacitors and / or capacitors can also be connected in series on the connecting path 21 between the two busbars IIa and IIb, and even taps and connections between the capacitances and body ground are possible. It is also possible, in addition to and in series with the at least one capacitance to switch further components, such as coils on the connecting path 21 between the two busbars IIa and IIb. However, a connection between the two busbars and the interposition of capacitors via ground is excluded. The same applies to the additional capacitance 19 ', 119' which is provided between two interconnected heating conductors and a busbar. hen (if required, more pairs of heating elements can be interconnected, so that even more capacity bridges can be provided).

As can be seen from FIG. 2, the connection 9c is preferably aligned parallel to the adjacent busbar IIb and lies there at a slight distance from the busbar IIb. This distance between the connection 9c and the adjacent busbar IIb should preferably be less than 80%, in particular 60%, 45%, 20% or even less than 10% of the length of the connection 9c.

Notwithstanding the embodiment shown, the two busbars could also be provided on different, non-opposite sides of the disc 1. For example, the busbar IIa shown in the further exemplary embodiment according to FIG. 3 is provided in the region of the lower boundary 1b of the disk 1, whereas the second busbar IIb is arranged, for example, on the right-hand edge Id of the disk 1 in the vertical direction. In this case, so part-circular or partially oval-shaped, curved heating conductors are provided.

In the exemplary embodiment according to FIG. 3 too, the two innermost heating conductors 9a and 9b are interconnected at one end via a transverse connection 9c and their opposite heating conductor ends are connected to the two busbars IIa and IIb, whereby here also the two busbars at a small distance from each other and in the free space 121 between the two busbar ends 11 'a and 11' b, the mentioned capacitance 19 in the form of the capacitor 119 on the connection connection section 21 is connected. In the exemplary embodiment shown, the busbar IIb provided predominantly on the right side Id on the disk 1 with its section 11 'b is also provided with an angled extension 111b, which in turn extends at the lower disk edge 1b in the immediate extension of the first busbars IIa provided there ,

By the mentioned connection 9c between the two innermost heating conductors 9a and 9b, a longer heating conductor is again provided here, whereby it is achieved that the thicknesses of the heating wires do not have to vary so much from the inside to the outside due to the different lengths. The mentioned connection 9c between the two innermost heating conductors 9a and 9c is also in turn electrically connected via a further capacitance 19 'in the form of a capacitor 119' to the right busbar IIb.

In this exemplary embodiment too, the outer heating conductors 9 (with the exception of the two innermost interconnected heating conductors 9a and 9b) are connected via a secondary line 15, which thus lies on the equipotential surfaces, whereby no transverse currents flow between the individual heating conductors.

Finally, reference is made to Figure 4, which shows a slightly modified embodiment of Figure 2.

In the embodiment according to FIG. 4, again, similar to the exemplary embodiment according to FIG. 2, two concentrically extending part-circular heating elements are shown. Conductors 9a and 9b connected to each other via a central portion 9c, wherein between this central portion 9c and the one busbar IIb, a capacitance 19 'is connected.

In this embodiment, between the two mentioned heating conductors 9a and 9b two further heating conductors 9'a and 9'b interconnected via an intermediate portion 9 ¹ C, between this intermediate portion 9'c and the aforementioned intermediate portion 9c (the other two heating conductors 9a and 9b) a capacity 19 ", preferably in the form of a capacitor 119" is additionally connected. This variant can also be provided as an alternative or in addition to the other capacities 19, 19 '. In the embodiment shown, the two intermediate portions 9c and 9 ¹ C parallel to each other and parallel to the adjacent busbar IIb extending running. The two further heating wires 9'a and 9'b are connected to connection points 1009 'and 1009 "adjacent to the connection points 109' and 109" on the two busbars IIa and IIb.

As already mentioned, the heating and / or antenna field can also comprise other curve shapes, including, for example, trapezoidal heating conductors for the arrangement. It is also possible to provide even more secondary connecting lines running transversely to the equipotential surfaces. The mentioned connection lines can be designed differently. In addition, as shown at the beginning in FIG. 3, differently designed additional antenna fields 105 can also be provided.

In any case, the invention gere frequency dependence and thus realize a greater bandwidth with respect to the antenna reception and improve the resonance behavior.

The embodiments have been described for the case that between the respective connection points in question, a capacity 19, 19 'or 19 "is connected, ie between the two connection points of the busbar, between a central portion of a Heizlei- ters and a busbar or The respective capacitance in question can also be connected to at least one further additional component, preferably an inductance or coil, which is preferably connected in series or series with the respective capacitance, that is to say in particular during generation Thus, in particular on the connecting path 21, therefore, a capacitance and an inductance or a coil can be connected directly in series.

Claims

Claims:

1. Antenna field for a motor vehicle windscreen, in particular a rear window with the following features: at least one heating field (7) with a plurality of conductors (9) is provided,

- The at least one heating field (7) forming conductor (9) are provided between at least two busbars (IIa, IIb) extending in or on the disc (1), preferably in equidistant arrangement, the heating field (7) is wholly or partly as Antenna field (5) connected and / or there is at least in addition to a heating field (7) at least one separate antenna array (5 ¹ ) provided with at least one antenna conductor (105),

- The at least two busbars (IIa, IIb) are provided on one or two non-opposite sides of the disc (1), characterized by the following further features: between one of the two busbars (IIa, IIb) and at least one between 20% and 80 % of the total length of a heating wire (9; 9a, 9b, 9c) formed central portion (9c) of the heating wire (9a, 9b, 9c) is at least at least one capacitance (19 ') is connected, and / or between at least two middle sections formed between 20% and 80% of the total length of two heating wires (9; 9a, 9b, 9c; 9'a, 9'b, 9'c) (9c, 9'c) of the heating wires (9; 9a, 9b, 9c; 9'a, 9'b, 9 ¹ C), at least one capacitor (19 ") is connected, and the at least one capacitor (19 ¹ , 19 ") is greater than 50 pF.

2. Antenna array according to claim 1, characterized in that the at least one capacitance (19 ') scarf in a direct connection between the associated connection point on the busbar (IIa, IIb) and the relevant central portion (9c) of the associated heating wire (9) - tet is.

3. Antenna array according to claim 1, characterized in that the at least one capacitance (19 ") in a direct connection between the associated connection points at the two central sections (9c, 9'c) of the heating wires (9; 9a, 9b, 9c; 9'a, 9'b, 9'c) is switched.

Antenna field according to one of Claims 1 to 3, characterized in that the at least one capacitance (19 ', 19 ") consists of a discrete component, i.e. a capacitor (119, 119').

5. Antenna array according to claim 4, characterized in that the capacitance (19 ', 19 ") of an electrolytic capacitor, a ceramic capacitor, a surface mountable component (SMD component) or layered one above the other arranged parallel to the disc plane isolated Tracks is or includes.

6. Antenna field according to one of claims 1 to 5, characterized in that the capacitance (19 ¹ , 19 ") is greater than 50 pF and less than 10 μF, in particular greater than 50 pF, 0.1 nF, 0, 25 nF, 0.5 nF, 1 nF, 3 nF, 5nF, 0.1 μF, 0.25 μF, 0.5 μF, 1 μF or even greater than 3 μF or greater than 5 μF, and that the capacitance (19 ¹ , 19 ") is preferably less than 5 μF, 1 μF and in particular less than 0.5 μF.

7. Antenna array according to one of claims 1 to 6, characterized in that at least one further component is connected in series to the at least one capacitance (19 ', 19 "), in particular a coil or an inductor to form a series or Reihenschwingkrei - ses.

8. Antenna field according to one of claims 1 to 7, characterized in that two heating conductors (9a, 9b; 9'a, 9'b) are provided, which extend at least over a part of their path adjacent and in particular equidistant from each other and the with extension of their entire heating conductor length at their one end region via a connecting portion (9c, 9 'c) are interconnected, whereas the respective opposite ends of the two heating conductors (9a, 9b, 9'a, 9'b) each with one of the two busbars (IIa, IIb) are connected.

9. An antenna field according to claim 8, characterized in that the connecting portion (9c, 9 ¹ C) parallel to an adjacent busbar (IIa, IIb) and / or that the two connecting portions (9c, 9'c) parallel to each other.

10. Antenna array according to claim 8 or 9, characterized in that two pairs of two heating conductors (9a, 9b, 9'a, 9'b) are provided which extend adjacent at least over part of their path and in particular equidistant from each other and the Lower extension of their entire Heizleiter-length respectively at its one end region via a connecting portion (9c, 9'c) are interconnected, whereas the opposite ends of the two pairs of heating conductors (9a, 9b, 9'a, 9'b) respectively are connected to one of the two busbars (IIa, IIb), and that the two connecting portions (9c; 9 ¹ C) are connected by means of the at least one capacitance (19 ").

11. Antenna array according to claim 9 or 10, characterized in that the two pairs of two heating conductors (9a, 9b, 9'a, 9'b) including their respective associated connecting portions (9c, 9'c) only at their ends with the respective busbar (IIa, IIb) and with their associated connecting portion (9c; 9'c) are electrically connected only to the at least one capacitance (19 ').

12. Antenna array according to one of claims 8 to 11, character- ized in that the one pair of heating conductors

(9'a, 9'b) including the associated connecting portion (9 'c) spatially between the two further connected further heat conductors (9a, 9b) including the associated connecting conductor (9c).

13. Antenna field according to one of claims 8 to 12, characterized in that the connecting portion (9c, - 9'c) a distance to the adjacent busbar (IIa, IIb) smaller than the length of the connecting portion (9c), preferably smaller than 80%, 60%, 40%, 20% or even smaller than 10% of the length of the connecting portion (9c).

14. Antenna field according to one of claims 1 to 13, characterized in that the adjacent ends (11 'a, 11' b) of the at least two bus bars (IIa, IIb) are at a small distance from each other, wherein the distance space (121) less than is five times, preferably less than four times, less than three times or less than twice the distance between two adjacent heating conductors (9, 9a, 9b).

15. Antenna field according to claim 14, characterized in that the spacing space (121) between the first and second busbars (IIa, IIb) is provided so that one of two adjacent and via the connection (9c) interconnected heating wires (9; 9b) is connected to the end (11 'a) of the first busbar (IIa) and the other heating wire (9; 9b) is connected to the end (ll'b) of at least one further busbar (IIb).

16. Antenna field according to one of claims 1 to 15, characterized in that the two busbars (IIa,

IIb) are provided symmetrically to a vertically extending plane of symmetry (14) on or in the disc (1).

17 antenna field according to one of claims 1 to 16, characterized in that the at least two bus bars (IIa, IIb) on the same side of the disc (1) preferably at the lower edge region adjacent to the lower boundary (Ib) of the disc (1) are arranged.

18. Antenna field according to one of claims 1 to 17, characterized in that a collecting field (11) adjacent to the left or right boundary (Ic, Id) is provided.

19. Antenna field according to one of claims 1 to 18, characterized in that at least one busbar (IIa, IIb) comprises at two angles aligned portions, wherein a portion (111b) on one side (Ib) of the disc (1) and the another portion (III'b) is disposed on another adjacent side (Id) of the disk (1).

20. Antenna array according to claim 19, characterized in that the one portion (111b) of the busbar (IIb) on the same side (Ib) of the disc (1) is arranged, on which also the first busbar (IIa) is arranged.

21. Antenna field according to one of claims 1 to 20, character- ized in that at least one secondary line

(15) is provided, over which at least a part of the heating conductors (9) is connected to equipotential surfaces.