EP2572403B1 - Antenna with optimised bandwidth with optimised construction of surface and line transmitter - Google Patents

Description

The invention relates to a hybrid antenna structure of surface and line radiator.

Substrates with electrically conductive coatings have already been described many times in the patent literature. By way of example only, reference is made to the documents DE 19858227 C1 . DE 102008018147 A1 and DE 102008029986 A1 directed. As a rule, the conductive coating serves for reflection of heat rays and thus, for example, in motor vehicles or in buildings for improving the thermal comfort. In many cases, it is also used as a heating layer to heat a transparent pane over its entire surface electrically.

For example, from the publications DE 10106125 A1 . DE 10319606 A1 . EP 0720249 A2 and US 2003/0112190 A1 is known, transparent coatings can be used because of their electrical conductivity as a planar antenna for receiving electromagnetic waves. For this purpose, the conductive coating is galvanically or capacitively coupled to a coupling electrode and the antenna signal is provided in the edge region of the disk. Via a connecting conductor, typically with the interposition of an antenna amplifier, the antenna signals are fed to a receiving device. As connection conductors usually unshielded stranded wires or foil conductors are used, which have a relatively low ohmic resistance and cause only low ohmic power losses, but do not allow a defined signal transmission, as it may come by unavoidable positional tolerances to undefined couplings with the electrically conductive vehicle body or adjacent conductors so that the variability of important antenna characteristics such as bandwidth, efficiency and foot-point impedance is relatively large. For this reason, such unshielded conductors must be kept relatively short.

Due to the use of special high-frequency conductors, which in addition to a signal conductor lead at least one ground conductor (coaxial, Koplanarleiter, microstrip conductor, etc.) signal losses can be avoided. However, such high-frequency conductors are complex and expensive and require a relatively large amount of space. In addition, they require an equally elaborate Connection technology. In motor vehicles, the antenna amplifier is electrically connected to the electrically conductive vehicle body, wherein a high frequency technically effective reference potential (ground) for the antenna signal is predetermined by this electrical connection. The usable antenna voltage results from the difference between the reference potential and the potential of the antenna signal.

The conductive coating serving as a sheet-like antenna for receiving electromagnetic waves is referred to herein and hereinafter as a "surface radiator" due to the fact that it can also be used for transmitting electromagnetic waves. By contrast and in contrast to surface radiators, line-shaped antennas or line antennas for receiving electromagnetic waves, which are also referred to herein as "line radiators", have a geometric length (L) whose geometric width (B) is several orders of magnitude exceeds. The geometric length of a line radiator is the distance between antenna base and antenna tip, the geometric width of the vertical dimension. The following applies to linear emitters: L / B ≥ 100. The same applies to line antennas for their geometric height (H), which is to be understood as a dimension that is perpendicular both to the length (L) and perpendicular to the width (B ), with the following relationship as a rule: L / H ≥ 100.

The antennas used in conventional windshields (not equipped with a conductive coating) are of the line emitter type, as they may also be used in motor vehicle windscreens, provided that they do not impair the driver's visibility in accordance with legal requirements. This can be achieved for example by fine wires with a diameter of typically 10 to 150 microns.

By line emitters in the range of the terrestrial bands II to V, a satisfactory antenna signal can be provided. According to a definition of the International Telecommunication Union (ITU = I nternational T elecommunication U nion) is this is the frequency range from 87.5 MHz to 960 MHz (band II: 87.5 to 100 MHz, Volume III: 162-230 MHz, Band IV: 470-582 MHz, Band V: 582-960 MHz). However, line emitters in the upstream frequency range of band I (41-68 MHz) can no longer achieve a satisfactory reception power. The same applies to frequencies below Band I.

If such a conventional configuration, consisting of windshield and line radiator, additionally equipped with an electrically conductive layer, that is, a line emitter is loaded with an electrically conductive layer, the line emitter loses its broadband properties. This is due primarily to the Nahfeldverkopplung between area and line emitter and a line emitter shielding effect of the conductive layer, which in particular with increasing frequency has a negative effect on the reception power of the line emitter. Even a wide variation of the electrical length of the line radiator does not lead to the desired reception characteristics of a broadband, at least the frequency range of the band II - V satisfactorily covering antenna.

On the other hand, a particularly good reception power in the frequency range of band I and a reception power comparable to the line radiator in the frequency range of band II can be achieved by the area radiator. However, the receiving power of the area radiator degrades at higher frequencies due to the relatively high surface electrical resistance of the conductive coating. In motor vehicles comes as a further cause a strong capacitive coupling between the conductive coating and the electrically conductive vehicle body added. This problem can be counteracted by a coating-free edge zone, which, however, may not be arbitrarily wide, since the transition into the edge zone should be concealed by an opaque edge strip with regard to an optically acceptable result. On the other hand, the other functions of the conductive coating, such as its heat radiation reflecting property, worsen with broadening of the peripheral zone. In practice, therefore, the edge zones typically have a width of 10 mm or less.

An improved reception performance can be compared with that in the unpublished international patent application PCT / EP2009 / 066237 An antenna disc can be achieved in which a segmentation of the electrically conductive coating causes an enlargement of the high-frequency technically effectively effective distance between the conductive coating and the electrically conductive vehicle body.

It would also be conceivable to improve the reception power of the area radiator by reducing the electrical surface resistance. This requires an increase in the layer thickness of the conductive coating, which, however, is always associated with a reduction in the optical transmission and, despite the practicality due to legal requirements is only possible to a limited extent.

As is known to the person skilled in the art, the positioning of the antenna base point at which the radio-frequency signal is tapped can also be used to influence the reception power of the area radiator. In practice, however, this approach leads to problems, since such an optimized Antennenfußpunkt of the downstream electronics (for example, antenna amplifier) is often far away. Since their spatial position is usually not changeable due to the available installation space and the special requirements with regard to safety and economy, a large spatial distance may have to be bridged. An improved reception power can thus be offset by a relatively long signal transmission path between the antenna base and the downstream electronics. To avoid signal losses and in terms of reproducibility, it is thus often necessary to use special high-frequency conductors, the disadvantages of which have already been described above.

the US Patent No. 4768037 A An antenna assembly according to the preamble of claim 1 can be taken. Further prior art can be found in the following publications: US 5128685 A . US 5285048 A . US 4736206 A . EP 0418047 A2 and EP 1858114 A1 ,

In contrast, the object of the present invention is to develop a conventional antenna structure in such a way that electromagnetic signals over the full reception range of the terrestrial radio bands I-V can be received with satisfactory reception power. These and other objects are achieved according to the proposal of the invention by a hybrid antenna structure having the features of the independent claim. Advantageous embodiments of the invention are indicated by the features of the subclaims.

The hybrid antenna structure of the present invention comprises at least one electrically insulating, preferably transparent substrate, as well as at least one electrically conductive, preferably transparent coating which at least partially covers at least one surface of the substrate and at least partially as a planar antenna (surface antenna or surface radiator) for receiving electromagnetic waves is used. The conductive coating is adapted for use as a planar antenna and may for this purpose cover the substrate over a large area. The antenna structure further comprises at least one coupling electrode electrically coupled to the conductive coating for decoupling Antenna signals from the surface antenna. The coupling electrode may, for example, be capacitively or galvanically coupled to the conductive coating.

According to the proposal of the invention, the coupling electrode with an unshielded, linear conductor, hereinafter referred to as "antenna conductor", electrically coupled. The antenna conductor serves as a line antenna for receiving electromagnetic waves and is designed to be suitable for this purpose, that is, it has a shape suitable for reception in the desired frequency range. As a line antenna or line emitter of the antenna conductor meets the conditions mentioned above with respect to its dimension in the extension direction (length L) and the two perpendicular dimensions (width B, height H). The antenna conductor may be formed, for example, in wire form or as a flat conductor. The coupling electrode may, for example, be capacitively or galvanically coupled electrically to the line-shaped antenna conductor.

What is essential here is that the unshielded, line-shaped antenna conductor is located outside a space defined by a projection operation, which is defined by the fact that each point of the space can be projected by an orthogonal parallel projection onto the conductive coating or surface antenna serving as the projection surface. If the conductive coating is only partially effective as an area antenna, serves as a projection surface only effective as a surface antenna part of the conductive coating. The line-shaped antenna conductor is therefore not located in the space defined by the projection operation. As usual, in the case of the parallel projection, the projection beams are parallel to one another and meet at right angles to the projection surface, which in the present case is provided by the conductive coating serving as surface antenna or its surface antenna, the projection center being at infinity. For a planar substrate and a thus planar conductive coating, the projection surface is a projection plane containing the coating. The said space is bounded by an imaginary edge surface which is positioned at the circumferential edge of the conductive coating or at the circumferential edge of the surface-antenna-active part of the conductive coating and is perpendicular to the projection surface.

In the hybrid antenna structure of the present invention, an antenna base of the line antenna becomes a common antenna base of the line and plane antenna. As usual, the term "antenna base" describes an electrical contact for tapping received antenna signals, in particular a reference to a reference potential (eg ground) for determining the signal level of the antenna signals.

The antenna structure according to the invention thus has an area antenna and a line antenna, which are electrically coupled to each other, which is referred to in the context of the present invention as a "hybrid antenna structure". It advantageously allows a good reception performance with a high bandwidth, which combines the favorable reception properties of the area radiator in the frequency ranges of bands I and II with the favorable reception properties of the line radiator in the frequency ranges of bands II to V. By positioning the line radiator outside the space which can be projected onto the planar antenna by means of orthogonal parallel projection, electrical loading of the line radiator by the area radiator can be avoided in a particularly advantageous manner. The hybrid antenna structure according to the invention thus makes the complete frequency range of the bands I to V available for the first time with a satisfactory reception power, for example for a windshield serving as an antenna disk. In industrial mass production, the hybrid antenna construction can be easily and inexpensively manufactured using common manufacturing techniques.

In an advantageous embodiment of the hybrid antenna structure according to the invention, the line-shaped antenna conductor for reception in the terrestrial bands III-V is specially adapted and for this purpose preferably has a length of more than 100 millimeters (mm) and a width of less than 1 mm and a height of less than 1 mm, corresponding to a ratio length / width ≥ 100 or L / H ≥ 100. For the desired purpose, it is further preferred if the antenna conductor has a line conductivity of less than 20 ohm / m, more preferably less than 10 ohms / m.

In a further advantageous embodiment of the hybrid antenna structure according to the invention, the coupling electrode is electrically coupled to the conductive coating such that the received power (signal level) of the surface antenna is as high as possible. This measure advantageously makes it possible to optimize the signal level of the planar antenna in order to improve the reception properties of the hybrid antenna structure.

In a further advantageous embodiment of the hybrid antenna structure according to the invention, the common Antennenfußpunkt of surface and line antenna by a connecting conductor with an electronic signal processing device for processing received antenna signals, such as an antenna amplifier, electrically conductively connected, wherein the terminal contact is arranged so that the length of the connecting conductor is as short as possible. This measure advantageously enables a specific high-frequency conductor with signal conductor and at least one entrained ground conductor not necessarily to be used for the terminal conductor, but that a cost-effective signal conductor not specifically intended for the high-frequency line, such as an unshielded stranded wire or ribbon-shaped flat conductor, is used due to the short signal transmission path can, which is connectable by a relatively inexpensive connection technology. This can be saved to a considerable extent costs in the production of the hybrid antenna structure.

In a further advantageous embodiment of the hybrid antenna structure according to the invention, the conductive coating covers the surface of the substrate except for a circumferential, electrically insulated edge strip, wherein the line-shaped antenna conductor is located within a space which can be projected by orthogonal parallel projection on the edge strip serving as a projection surface. For this purpose, the line-shaped antenna conductor can be applied to the substrate, for example in the region of the edge strip. This measure allows a particularly simple production of the hybrid antenna structure.

In a further advantageous embodiment of the hybrid antenna structure according to the invention, this is realized in the form of a composite pane. The composite pane comprises two preferably transparent first substrates, which correspond to an inner and outer pane, which are firmly connected to one another by at least one thermoplastic adhesive layer. In this case, the conductive coating may be located on at least one surface of at least one of the first two substrates of the composite pane. In addition, the composite pane can be provided with a further second substrate, which is different from the first substrate and which is located between the two first substrates. The second substrate, in addition to or as an alternative to the first substrates, can serve as a carrier for the conductive coating, wherein at least one surface of the second substrate is provided with the conductive coating. By virtue of this measure, the hybrid antenna structure according to the invention can be technically realized in a particularly simple manner.

In a further advantageous embodiment of the hybrid antenna structure according to the invention, the conductive coating is on a surface of the at least one substrate and the line-shaped antenna conductor on a different surface thereof or a different substrate. By this measure, a particularly simple production of the hybrid antenna structure according to the invention can be realized.

In a further advantageous embodiment of the hybrid antenna structure according to the invention, the coupling electrode and the antenna conductor are electrically conductively connected to each other by a first connection conductor, which in particular provides the possibility to design the coupling electrode independently of the electrical connection to the linear antenna conductor, whereby the performance of the hybrid antenna structure can be improved.

In a further advantageous embodiment of the hybrid antenna structure according to the invention, the antenna conductor is located on a surface of the at least one substrate and the common antenna base on a different surface thereof or a different substrate. For this purpose, the antenna conductor and the common Antennenfußpunkt are electrically connected to each other by a second connection conductor. By this measure, in particular the electrical connection of the common Antennenfußpunkts can be realized with the downstream antenna electronics in a particularly simple manner.

In a further advantageous embodiment of the hybrid antenna structure according to the invention, the line-shaped antenna conductor of a metallic printing paste, for example by screen printing, printed on the at least one substrate or laid in the form of a wire, whereby a particularly simple production of the antenna conductor is made possible.

In a further advantageous embodiment of the hybrid antenna structure according to the invention, at least one of the conductors, selected from the coupling electrode, first connection conductor and second connection conductor, leads to the edge of the at least one substrate and is designed as a flat conductor with a width tapered in the region of the edge. By this measure, a reduced coupling surface on the substrate edge, for example, at the exit of the conductor from the composite disk for reducing a capacitive coupling with the electrically conductive vehicle body can be achieved in an advantageous manner.

In a further advantageous embodiment of the hybrid antenna structure according to the invention, the line antenna and the coupling electrode and the two connecting conductors (if present) are covered by an opaque masking layer, whereby the optical appearance of the antenna structure can be improved.

According to the invention, the conductive coating comprises at least two planar segments which are insulated from one another by at least one line-shaped, electrically insulating region. In addition, at least one sheet-shaped segment is divided by linearly electrically insulating regions. In this case, an in particular peripheral edge region of the conductive coating has a multiplicity of planar segments which are subdivided by linearly electrically insulating regions. Such a design of the conductive coating is in the previously mentioned, unpublished international patent application PCT / EP2009 / 066237 described in detail.

The line-shaped antenna conductor can be arranged at least in sections, in particular completely, in the region of such sheet-like, electrically insulated segments. In particular, the line-shaped antenna conductor can be arranged at least in sections, in particular completely, within a space which can be projected by orthogonal parallel projection onto the region of such sheet-like, electrically isolated segments serving as a projection surface.

• Bedecken zumindest eines Abschnitts zumindest einer Oberfläche zumindest eines elektrisch isolierenden, vorzugsweise transparenten Substrats mit zumindest einer elektrisch leitfähigen, vorzugsweise transparenten Beschichtung, welche als Flächenantenne zum Empfangen von elektromagnetischen Wellen dient;
• Ausbilden zumindest eines ungeschirmten, linienförmigen Antennenleiters, der als Linienantenne zum Empfangen von elektromagnetischen Wellen dient, wobei sich der Antennenleiter außerhalb eines Raums befindet, der durch orthogonale Parallelprojektion auf die Flächenantenne projizierbar ist;
• Herstellen zumindest einer Koppelelektrode, welche mit der leitfähigen Beschichtung und dem linienförmigen Antennenleiter elektrisch gekoppelt ist.

A method for producing a hybrid antenna structure is also shown, which comprises the following steps:

• Covering at least a portion of at least one surface of at least one electrically insulating, preferably transparent substrate with at least one electrically conductive, preferably transparent coating, which serves as a planar antenna for receiving electromagnetic waves;
• Forming at least one unshielded, line-shaped antenna conductor serving as a line antenna for receiving electromagnetic waves, the antenna conductor being located outside a space that can be projected onto the planar antenna by orthogonal parallel projection;
• Producing at least one coupling electrode, which is electrically coupled to the conductive coating and the linear antenna conductor.

In an advantageous embodiment of the method, the line-shaped antenna conductor is printed by means of a metallic printing paste on the at least one substrate or laid in the form of a wire in particular between two interconnected in the form of a composite disc substrates.

The invention further extends to the use of a hybrid antenna structure as described above as a built-in furniture, appliances and buildings, and in locomotion means for locomotion on land, in the air or on water, especially in motor vehicles, for example, as a windshield, rear window, side window and / or glass roof.

It is understood that the various configurations of the antenna structure according to the invention can be implemented individually or in any desired combinations. In particular, the features mentioned above and to be explained below can be used not only in the specified combinations but also in other combinations or in isolation, without departing from the scope of the present invention.

Brief description of the drawings

Fig. 1

eine schematische perspektivische Ansicht eines in Form einer Verbundscheibe verkörperten, hybriden Antennenaufbaus gemäß einem ersten Ausführungsbeispiel der Erfindung;

Fig. 2A-2B

Schnittansichten des hybriden Antennenaufbaus von Fig. 1 gemäß Schnittlinie A-A (Fig. 2A) und Schnittlinie B-B (Fig. 2B);

Fig. 3A-3B

Schnittansichten einer ersten Variante des hybriden Antennenaufbaus von Fig. 1 gemäß Schnittlinie A-A (Fig. 3A) und Schnittlinie B-B (Fig. 3B);

Fig. 4A-4B

Schnittansichten einer zweiten Variante des hybriden Antennenaufbaus von Fig. 1 gemäß Schnittlinie A-A (Fig. 4A) und Schnittlinie B-B (Fig. 4B);

Fig. 5A-5B

Schnittansichten einer dritten Variante des hybriden Antennenaufbaus von Fig. 1 gemäß Schnittlinie A-A (Fig. 5A) und Schnittlinie B-B (Fig. 5B);

Fig. 6

eine Schnittansicht einer vierten Variante des hybriden Antennenaufbaus von Fig. 1 gemäß Schnittlinie B-B;

Fig. 7

eine schematische perspektivische Ansicht eines in Form einer Verbundscheibe verkörperten hybriden Antennenaufbaus gemäß einem Beispiel;

Fig. 8A-8B

Schnittansichten des hybriden Antennenaufbaus von Fig. 7 gemäß Schnittlinie A-A (Fig. 8A) und Schnittlinie B-B (Fig. 8B);

Fig. 9

eine Schnittansicht einer Variante des hybriden Antennenaufbaus von Fig. 7 gemäß Schnittlinie A-A.

The invention will now be explained in more detail by means of embodiments, reference being made to the accompanying figures. In a simplified, not to scale representation:

Fig. 1

a schematic perspective view of an embodied in the form of a composite disc, hybrid antenna structure according to a first embodiment of the invention;

Fig. 2A-2B

Section views of the hybrid antenna assembly of Fig. 1 according to section line AA ( Fig. 2A ) and section line BB ( Fig. 2B );

FIGS. 3A-3B

Sectional views of a first variant of the hybrid antenna assembly of Fig. 1 according to section line AA ( Fig. 3A ) and section line BB ( Fig. 3B );

Fig. 4A-4B

Sectional views of a second variant of the hybrid antenna structure of Fig. 1 according to section line AA ( Fig. 4A ) and section line BB ( Fig. 4B );

Fig. 5A-5B

Sectional views of a third variant of the hybrid antenna assembly of Fig. 1 according to section line AA ( Fig. 5A ) and section line BB ( Fig. 5B );

Fig. 6

a sectional view of a fourth variant of the hybrid antenna assembly of Fig. 1 according to section line BB;

Fig. 7

a schematic perspective view of a composite in the form of a composite disc hybrid antenna structure according to an example;

Figs. 8A-8B

Section views of the hybrid antenna assembly of Fig. 7 according to section line AA ( Fig. 8A ) and section line BB ( Fig. 8B );

Fig. 9

a sectional view of a variant of the hybrid antenna structure of Fig. 7 according to section line AA.

Detailed description of the drawings

Be first Fig. 1 . 2A and 2 B which, as a first embodiment of the invention, illustrates a hybrid antenna construction, generally designated by the reference numeral 1. The hybrid antenna assembly 1 is embodied here, for example, as a transparent composite disk 20, which in Fig. 1 only partially shown. The composite pane 20 is transparent to visible light, for example in the wavelength range from 350 nm to 800 nm, the term "transparency" being understood to mean a light transmission of more than 50%, preferably more than 75% and especially preferably more than 80%. The composite disk 20 serves, for example, as a windshield of a motor vehicle, but it can also be used elsewhere.

The composite pane 20 comprises two transparent individual panes, namely a rigid outer pane 2 and a rigid inner pane 3, which are firmly connected to each other via a transparent thermoplastic adhesive layer 21. The individual panes have approximately the same size and are made for example of glass, in particular float glass, cast glass and ceramic glass, being equally made of a non-glassy material, such as plastic, in particular polystyrene (PS), polyamide (PA), polyester (PE), polyvinyl chloride (PVC), polycarbonate (PC), polymethylmethacrylate (PMA) or polyethylene terephthalate (PET). In general, any material with sufficient transparency, sufficient chemical resistance and proper dimensional and dimensional stability can be used. For other use, for example as a decorative part, it would also be possible, the outer and inner panes 2, 3 to produce a flexible material. The respective thickness of the outer and inner panes 2, 3 may vary widely depending on the use and may be, for example, in the range of 1 to 24 mm for glass.

The composite disk 20 has an at least approximately trapezoidal curved contour (in Fig. 1 only partially recognizable), which results from a disc rim 5 common to the two individual discs 2, 3, wherein the disc rim 5 is composed of two opposite long disc edges 5a and two opposite short disc edges 5b. In the usual way, the disk surfaces are denoted by the Roman numerals I-IV, wherein "side I" of a first disk surface 24 of the outer disk 2, "side II" of a second disk surface 25 of the outer disk 2, "side III" of a third disk surface 26 of the inner disk 3 and "side IV" of a fourth disc surface 27 of the inner pane 3 corresponds. In use as a windshield side I of the external environment and side IV of the passenger compartment of the motor vehicle faces.

The adhesive layer 21 for connecting the outer and inner pane 2, 3 is preferably made of an adhesive plastic, preferably based on polyvinyl butyral (PVB), ethylene-vinyl acetate (EVA) and polyurethane (PU). Here, the adhesive layer 21 is formed for example as a bilayer in the form of two bonded together PVB films, which is not shown in more detail in the figures.

Between the outer and inner pane 2, 3 there is a planar support 4, preferably made of plastic, preferably based on polyamide (PA), polyurethane (PU), polyvinyl chloride (PVC), polycarbonate (PC), polyester (PE) and polyvinyl butyral (PVB), particularly preferably based on polyester (PE) and polyethylene terephthalate (PET). Here, the carrier 4 is formed for example in the form of a PET film. The carrier 4 is embedded between the two PVB films of the adhesive layer 21 and arranged parallel to the outer and inner discs 2, 3 approximately centrally between the two, wherein a first carrier surface 22 of the second disc surface 25 and a second carrier surface 23 of the third disc surface 26th is facing. The carrier 4 does not extend all the way to the wafer edge 5, so that a carrier edge 29 is set back inwards relative to the wafer edge 5 and a carrier-free, all-round peripheral edge zone 28 of the composite wafer 20 remains. The edge zone 28 is used in particular for electrical insulation of the conductive coating 6 to the outside, for example, to reduce capacitive coupling with the electrically conductive, usually made of sheet metal vehicle body. In addition, the conductive coating 6 is protected against penetrating from the wafer edge 5 corrosion.

On the second support surface 23, a transparent, electrically conductive coating 6 is applied, which is bounded by a coating edge 8 which runs around on all sides. The conductive coating 6 covers an area which is more than 50%, preferably more than 70%, more preferably more than 80% and even more preferably more than 90% of the area of the second disk surface 25 and the third disk surface 26, respectively. The area covered by the conductive coating 6 is preferably more than 1 m ² and may generally be in the range of 100 cm ² to 25 m ² regardless of the use of the composite pane 20 as a windshield. The transparent, electrically conductive coating 6 contains or consists of at least one electrically conductive material. Examples of these are metals with a high electrical conductivity such as silver, copper, gold, aluminum or molybdenum, metal alloys such as palladium-alloyed silver, and transparent conductive oxides (TCO). TCO is preferably indium tin oxide, fluorine-doped tin dioxide, aluminum-doped tin dioxide, gallium-doped tin dioxide, boron-doped tin dioxide, tin zinc oxide or antimony-doped tin oxide.

The conductive coating 6 can consist of a single layer with such a conductive material or of a layer sequence which contains at least one such single layer. By way of example, the layer sequence may comprise at least one layer of a conductive material and at least one layer of a dielectric material. The thickness of the conductive coating 6 may vary widely depending on the use, and the thickness at each location may be, for example, in the range of 30 nm to 100 μm. In the case of TCO, the thickness is preferably in the range of 100 nm to 1.5 μm, preferably in the range of 150 nm to 1 μm, particularly preferably in the range of 200 nm to 500 nm. Is the conductive coating of a layer sequence with at least one Layer of an electrically conductive material and at least one layer of a dielectric material, the thickness is preferably 20 nm to 100 .mu.m, preferably 25 nm to 90 .mu.m, and particularly preferably 30 nm to 80 microns. Advantageously, the layer sequence can withstand high thermal loads so that it can withstand the temperatures required for bending glass panes of typically more than 600.degree. C. without damage, but it is also possible to provide thermally low-loadable layer sequences. The sheet resistance of the conductive coating 6 is preferably less than 20 ohms per unit area and is, for example, in the range of 0.5 to 20 ohms per unit area. in the In the embodiment shown, the sheet resistance of the conductive coating 6 is, for example, 4 ohms per unit area.

The conductive coating 6 is preferably deposited from the gas phase, for which purpose known methods such as chemical vapor deposition (CVD) or physical vapor deposition (PVD) can be used. Preferably, the coating 6 is applied by sputtering (magnetron sputtering).

In the composite disk 20, the conductive coating 6 serves as an area antenna for receiving electromagnetic waves, preferably in the frequency range of the terrestrial broadcasting bands I and II. For this purpose, the conductive coating 6 with a coupling electrode 10, which is here formed for example as a ribbon-shaped flat conductor, electrically coupled. In the exemplary embodiment, the coupling electrode 10 is galvanically coupled to the conductive coating 6, wherein a capacitive coupling may equally be provided. The band-shaped coupling electrode 10 consists for example of a metallic material, preferably silver, and is printed for example by screen printing. It preferably has a length of more than 10 mm with a width of 5 mm or larger, preferably a length of more than 25 mm with a width of 5 mm or larger. In the exemplary embodiment, the coupling electrode 10 has a length of 300 mm and a width of 5 mm. The thickness of the coupling electrode is preferably less than 0.015 mm. The specific conductivity of a coupling electrode 10 consisting of silver is, for example, 61.35 × 10 ⁶ / ohm · m.

As in Fig. 1 2, the coupling electrode 10 extends on and in direct electrical contact with the conductive coating 6 approximately parallel to the upper coating edge 8 and extends into the carrier-free edge zone 28. In this case, the coupling electrode 10 is arranged so that the antenna signals of the surface antenna are optimized in terms of their reception power (signal level).

As in Fig. 2A and 2 B 1, the conductive coating 6 is subdivided in a strip-shaped edge region 15 adjoining the support edge 29, for example by means of lasering, into a plurality of electrically insulated segments 16 between which electrically insulating (de-layered) regions 17 are located. The edge region 15 runs essentially parallel to the carrier surface 24 and can in particular be circumferential on all sides. As in the above-mentioned, unpublished international patent application PCT / EP 2009/066237 disclosed is, can be counteracted by this measure advantageously a capacitive coupling of the conductive coating 6 with surrounding conductive structures, such as an electrically conductive vehicle body. Since the edge region 15 of the conductive coating 6 as an area antenna is not effective, a part of the conductive coating 6 which is effective for the function as an area antenna is limited by a coating edge 8 '.

Within the carrier-free edge zone 28 of the composite disk 20 is embedded in the adhesive layer 4, a line-shaped, unshielded antenna conductor 12, as a line antenna for receiving electromagnetic waves, preferably in the frequency range of the terrestrial radio bands II to V, particularly preferably in the frequency range of the radio bands III to V and is designed to be suitable for this purpose. In the present embodiment, the antenna conductor 12 is in the form of a wire 18, which is preferably longer than 100 mm and narrower than 1 mm. The line conductivity of the antenna conductor 12 is preferably less than 20 ohm / m, more preferably less than 10 ohm / m. In the embodiment shown, the length of the antenna conductor 12 is about 650 mm with a width of 0.75 mm. Its line conductivity is, for example, 5 ohms / m.

Here, for example, the antenna conductor 12 has an at least approximately rectilinear profile and is located completely within the carrier-free and coating-free edge zone 28 of the composite pane 20, wherein it extends predominantly along the short pane edge 5b, for example below a vehicle trim (not shown) in the region of the masking strip 9 , In this case, the antenna conductor 12 has a sufficient distance from both the disk edge 5 and the coating edge 8, whereby a capacitive coupling with the conductive coating 6 and the vehicle body is counteracted. In particular, it is advantageously achieved by the segmented edge region 15 that the distance between the conductive coating 6 and the line antenna effective in terms of radio frequency technology is increased.

Since the antenna conductor 12 outside a in Fig. 2A schematically indicated space 30, which is defined by the fact that each point contained therein can be by orthogonal parallel projection on the projection surface representing serving as a surface antenna conductive coating 6 (or on the surface antenna effective part of the conductive coating 6) can be the line antenna is not electrically stressed by the surface antenna. This space 30 defined by a projection operation is defined by a mental boundary surface 32 which is arranged on the coating edge 8 or 8 'and perpendicular to the carrier 21 is directed, limited. For the segmented edge region 15, the boundary surface 32 is arranged on the coating edge 8 ', since the positioning of the antenna conductor 12 depends on the antenna function of the conductive coating 6. For this reason, it would equally be possible for the line-shaped antenna conductor 12 to be arranged at least in sections, in particular completely, within the segmented edge region 15. In other words, the line-shaped antenna conductor 12 could also be arranged at least in sections, in particular completely, within a space which is defined by the fact that each point contained therein can be imaged by orthogonal parallel projection on the segmented edge region 15 representing a projection surface. According to the invention, this variant is also included.

The coupling electrode 10 is electrically coupled to the linear antenna conductor 12 at a first terminal 11, not shown. In the present exemplary embodiment, the coupling electrode 10 is galvanically coupled to the antenna conductor 12, wherein a capacitive coupling may equally be provided. Although not shown in the figures, equally at least one further electrical coupling (coupling point or contact point) could be provided between the planar antenna, in particular the coupling electrode 10, and the linear antenna conductor 12. The first connection contact 11 of the coupling electrode 10 or the connection point between the coupling electrode 10 and the antenna conductor 12 can be regarded as Antennenfußpunkt for picking up antenna signals of the surface antenna. In fact, however, a second terminal contact 14 of the antenna conductor 12 serves as a common Antennenfußpunkt 13 for tapping the antenna signals of both the planar antenna and the line antenna. The antenna signals of the surface and the line antenna are thus provided at the second terminal contact 14.

The second terminal contact 14 is electrically coupled to a parasitic acting as an antenna terminal conductor 19. In the present exemplary embodiment, the connection conductor 19 is galvanically coupled to the second connection contact 14, although a capacitive coupling may also be provided. Via the connecting conductor 19 and an associated connector 31, the hybrid antenna assembly 1 is electrically connected to downstream electronic components, for example an antenna amplifier, the antenna signals being led out of the composite disk 20 through the connecting conductor 19. As in Fig. 2B is shown, the connecting conductor 19 extends from the adhesive layer 21 on the wafer edge 5 on the fourth disc surface 27 (page IV) and then leads away from the composite disc 20. In this case, the spatial position of the second connection contact 14 is selected such that the connection conductor 19 is as short as possible and its parasitic effect is minimized as an antenna, so that it can be dispensed with the use of a high-frequency technically specific conductor. The connection conductor 19 is preferably shorter than 100 mm. Accordingly, the connection conductor 19 is here for example designed as unshielded stranded wire or foil conductor, which is inexpensive and space-saving and can also be connected via a relatively simple connection technology. The width of the connecting conductor 19 formed here, for example, as a flat conductor, preferably tapers towards the edge of the pane 5 in order to counteract capacitive coupling with the vehicle body.

In the hybrid antenna structure 1, the transparent, electrically conductive coating 6, depending on the material composition, fulfill other functions. For example, it may serve as a heat ray-reflecting coating for purposes of sunscreen, thermoregulation or thermal insulation or as a heating layer for electrically heating the composite disk 20. These functions are of secondary importance to the present invention.

Furthermore, the outer pane 2 is provided with an opaque ink layer, which is applied to the second pane surface 25 (page II) and forms a frame-shaped circumferential masking strip 9, which is not shown in detail in the figures. The color layer is preferably made of an electrically non-conductive, black-colored material that can be baked into the outer pane 2. The masking strip 9 on the one hand prevents the view of an adhesive strand, with which the composite disc 20 can be glued into a vehicle body, on the other hand it serves as UV protection for the adhesive material used.

It will now be related to the FIGS. 3A and 3B wherein a first variant of the hybrid antenna assembly 1 is shown. To avoid unnecessary repetition, only the differences from the embodiment of FIGS. 1 . 2A and 2 B and otherwise reference is made to the statements made there.

Accordingly, no support 4 is provided for the conductive coating 6 in the composite pane 20, since this is applied to the third pane surface 26 (side III) of the inner pane 3. The conductive coating 6 does not extend all the way to the wafer edge 5, so that an edge strip 7 of the third wafer surface 26 which runs around on all sides and remains free of coating remains. The width of the peripheral edge strip 7 can vary widely. Preferably, the width of the edge strip 7 is in the range of 0.2 to 1.5 cm, preferably in the range of 0.3 to 1.3 cm and particularly preferably in the range of 0.4 to 1.0 cm. The edge strip 7 is used in particular an electrical Isolating the conductive coating 6 to the outside and to reduce a capacitive coupling with surrounding conductive structures. The edge strip 7 can be produced by subsequent removal of the conductive coating 6, for example by abrasive removal, laser ablation or etching, or by masking the inner pane 3 before the application of the conductive coating 6 to the third pane surface 26.

The antenna conductor 12 serving as a line antenna is applied to the third disk surface 26 in the region of the coating-free edge strip 7. In the variant shown, the antenna conductor 12 is formed in the form of a flat conductor track 35, which is preferably applied by printing, for example screen printing, a metallic printing paste. Thus, the line antenna and the surface antenna on the same surface (page III) of the inner pane 3. The band-shaped coupling electrode 10 extends beyond the line-shaped antenna conductor 12 and is galvanically coupled thereto, wherein a capacitive coupling may be provided equally. As has already been explained above, since the segmented edge region 15 does not fulfill an antenna function, it would be equally possible for the antenna conductor 12, 35 embodied as a conductor track to be arranged at least in sections, in particular completely, within the segmented edge region 15. In other words, the web-shaped antenna conductor 12, 35 could also be arranged at least in sections, in particular completely, within a space which is defined by the fact that each point contained therein can be imaged by orthogonal parallel projection on the segmented edge region 15 representing a projection surface.

The antenna radiator 12 is located outside the in Fig. 3A illustrated space 30, in which each point can be imaged by orthogonal parallel projection on the surface antenna, so that the line antenna is not electrically charged by the surface antenna. In Fig. 3A is the space 30 bounding (imaginary) boundary surface 32, which is directed perpendicular to the third disc surface 26 and at the coating edge 8 and 8 '(in the edge region 15) is arranged schematically. In other words, the line-shaped antenna conductor 12 is located in an unspecified space in which each point can be imaged by orthogonal parallel projection on the non-coating edge strip 7 serving as a projection surface. An electrical load on the line antenna by the planar antenna is thereby avoided in an advantageous manner.

In the FIGS. 4A and 4B a second variant of the hybrid antenna assembly 1 is shown, with only the differences from the first variant of the FIGS. 3A and 3B Be described and otherwise made to the statements made there reference.

Accordingly, no composite disk 20 but only a single-pane glass with a single pane corresponding to, for example, outer pane 2 is provided. The conductive coating 6 is applied to the first pane surface 24 (side I), wherein the conductive coating 6 does not extend all the way to the pane edge 5, so that a circumferential, coating-free edge strip 7 of the first pane surface 24 remains on all sides. In the region of the coating-free edge strip 7 serving as a line antenna, formed in the form of a conductor 35 line-shaped antenna conductor 12 is applied to the first disk surface 24. The antenna conductor 12 is thus located outside of in Fig. 4A illustrated space 30, in which each point can be imaged by orthogonal parallel projection on the surface antenna. The connection conductor 19 makes contact with the second connection contact 14 of the antenna conductor 12 and then leads away from the antenna conductor 12 on the same side of the outer pane 2.

In the Figures 5A and 5B a third variant of the hybrid antenna assembly 1 is shown, with only the differences from the first embodiment of the FIGS. 1 . 2A and 2 B Be described and otherwise made to the statements made there reference.

Accordingly, a carrier 4 is provided in the composite disk 20, on which the conductive coating 6 is applied. The band-shaped coupling electrode 10 is applied to the fourth surface (side IV) of the inner pane 3 and capacitively coupled to the surface coating serving as a conductive coating 6. Serving as a line antenna antenna conductor 12 is also on the fourth disc surface 27 of the inner pane 3, for example by printing, for example screen printing, applied and galvanically coupled to the coupling electrode, but equally a capacitive coupling can be provided. Thus, the patch antenna and the line antenna are on different surfaces of mutually different substrates. The antenna conductor 12 is located outside the space 30, in which each point can be imaged by orthogonal parallel projection on the surface antenna 6, so that the line antenna is not electrically stressed by the planar antenna. The connecting conductor 19 contacts the antenna conductor 12 and leads away directly from the composite disk 20.

In FIG. 6 a fourth variant of the hybrid antenna assembly 1 is shown, with only the differences from the third variant of the Fig. 5A and 5B Be described and otherwise made to the statements made there reference.

Accordingly, the line-shaped antenna conductor 12 formed as a flat conductor track 35 is applied to the third disk surface 26 of the inner disk 3. A second connecting conductor 34 is applied to the antenna conductor 12 at the base of the antenna and extends over the short disk edge 5b to the fourth disk surface 27 (side IV) of the inner disk 3. In the variant shown, the second connecting conductor 34 is galvanically coupled to the antenna conductor 12, where equally a capacitive coupling can be provided. The second connection conductor 34 may be made of the same material as the coupling electrode 10, for example. The connecting conductor 19 contacts the connecting conductor 19 on the fourth disk surface 27 and leads away from the composite disk 20. The width (dimension perpendicular to the extension direction) of the second connecting conductor 34 designed as a band-shaped flat conductor preferably tapers towards the short disk edge 5b, so that a capacitive coupling between the conductive coating 6 and the electrically conductive vehicle body can be counteracted.

In the Fig. 7 . 8A and 8B an example of an antenna structure 1 is illustrated, wherein only the differences from the first embodiment of the FIGS. 1 . 2A and 2 B Be described and otherwise made to the statements made there reference.

Accordingly, a composite disk 20 is provided with a carrier 4 embedded in the adhesive layer 21 and a transparent, conductive coating 6 applied on the second carrier surface 23. The conductive coating 6 is applied over the entire surface of the second support surface 23, wherein a segmented edge region 15 is not formed, however, may be provided equally.

The coupling electrode 10 is located on the conductive coating 6 and is galvanically coupled thereto, but equally a capacitive coupling can be provided. The coupling electrode 10 extends over the upper, long disk edge 5a on the fourth disk surface 27 (side IV) of the inner pane 3. The line-shaped antenna conductor 12 is analogous to that in connection with Fig. 5A and 5B described third variant of the first embodiment as a conductor 35 applied to the fourth disc surface 27 of the inner pane 3. At At its other end, the coupling electrode 10 is located on the antenna conductor 12 and is galvanically coupled thereto, but equally a capacitive coupling can be provided. The antenna conductor 12 is located outside of the space 30 in which each point can be imaged by orthogonal parallel projection on the surface antenna, so that the line antenna is not electrically stressed by the planar antenna. The connecting conductor 19 contacts the antenna conductor 12 and leads away directly from the composite disk 20.

In Fig. 9 a variant is shown, wherein to avoid repetition, only the differences from the second embodiment of Fig. 7 . 8A and 8B be explained. Accordingly, the coupling electrode 10 is formed only in the region of the conductive coating 6, this is in direct contact and is thus galvanically coupled to the conductive coating 6, wherein a capacitive coupling may equally be provided. A first connection conductor 33 is in direct contact with its one end of the coupling electrode 10 and is galvanically coupled to the conductive coating 6, but equally a capacitive coupling can be provided. The first connection conductor 33 extends beyond the upper long disk edge 5a to the fourth disk surface 27 (side IV) of the inner disk 3 and contacts with its other end the antenna conductor 12 formed as a conductor. The first connection conductor 33 is in direct contact with the antenna conductor 12 and is, for example, galvanically coupled to it via a soldering contact, but equally a capacitive coupling can be provided. The first connection conductor 33 may be made, for example, of the same material as the coupling electrode 10, so that the coupling electrode 10 and the first connection conductor 33 together can also be regarded as a two-part coupling electrode. The width (dimension perpendicular to the extension direction) of the band-shaped flat conductor formed first connection conductor 33 preferably tapers towards the long edge of the disk 5 a, so that a capacitive coupling between the conductive coating 6 and the vehicle body can be counteracted.

The invention provides a hybrid antenna structure which enables bandwidth-optimized reception of electromagnetic waves, wherein a satisfactory reception performance can be achieved through the combination of surface and line antenna over the entire frequency range of the bands IV.

LIST OF REFERENCE NUMBERS

• 1 antenna structure
• 2 outer pane
• 3 inner pane
• 4 carriers
• 5 slice edge
• 5a long wheel rim
• 5b short disc edge
• 6 coating
• 7 edge stripes
• 8, 8 'coating edge
• 9 masking strips
• 10 coupling electrode
• 11 first connection contact
• 12 antenna conductors
• 13 antenna base point
• 14 second connection contact
• 15 border area
• 16 segment
• 17 insulating area
• 18 wire
• 19 connection conductor
• 20 composite disk
• 21 adhesive layer
• 22 first support surface
• 23 second carrier surface
• 24 first disc surface
• 25 second disc surface
• 26 third disc surface
• 27 fourth disc surface
• 28 border zone
• 29 bearer edge
• 30 room
• 31 connector
• 32 boundary surface
• 33 first connecting conductor
• 34 second connection conductor
• 35 trace

Claims (10)

1. Antenna structure (1), comprising

   - an electrically insulating substrate (2-4),

   - an electrically conductive coating (6) that covers a surface (22-27) of the substrate and that serves as a planar antenna for reception of electromagnetic waves,

   - a coupling electrode (10) electrically coupled to the conductive coating (6) for coupling out of antenna signals from the planar antenna,

   wherein the coupling electrode (10) is electrically coupled to an unshielded, linear antenna conductor (12) that serves as a linear antenna for reception of electromagnetic waves, wherein the linear antenna conductor (12) is situated outside an area (30) which contains the planar antenna and is delimited by an imagined bounding surface (32) which is disposed at the circumferential edge of the planar antenna and is perpendicular to the planar antenna, wherein an antenna foot point of the linear antenna, which antenna foot point is used to tap received antenna signals, is a common antenna foot point (13) of the linear and planar antenna, characterized in that the conductive coating (6) has an edge region (15) which is not effective as a planar antenna and is adjacent to the planar antenna on the imagined bounding surface (32), and which has a plurality of planar segments (16) that are subdivided by linear electrically insulating regions (17), so that the distance between the conductive coating (6) and the linear antenna which is effective in terms of high frequency is increased.
2. Antenna structure (1) according to claim 1,
   characterized in that the linear antenna conductor (12) is situated inside an area which is defined in that every point contained therein can be imagined by orthogonal parallel projection onto the segmented edge region (15) representing a projection area.
3. Antenna structure (1) according to one of claims 1 or 2,
   characterized in that the conductive coating (6) covers the surface of the substrate (2-4) except for a circumferential, electrically insulating edge strip (7), wherein the linear antenna conductor (12) is applied on the substrate (2-4) in the region of the edge strip (7).
4. Antenna structure (1) according to one of claims 1 through 3,
   characterized in that the substrate (2-4) has a laminated pane formed from two substrates (2, 3) bonded to one another, wherein the conductive coating (6) is situated on a surface (24-27) of one of the two substrates (2, 3) bonded to each other of the laminated pane (20) or on a surface (22, 23) of a second substrate (4) disposed between the two substrates (2, 3).
5. Antenna structure (1) according to one of claims 1 through 4,
   characterized in that the conductive coating (6) is situated on a surface (22-27) of the substrate (2-4) and the linear antenna conductor (12) is situated on a different surface (22-27) of the same or of a different substrate (2-4).
6. Antenna structure (1) according to one of claims 1 through 5,
   characterized in that the coupling electrode (10) and the linear antenna conductor (12) are electrically conductively connected to each other via a first connection conductor (33).
7. Antenna structure (1) according to one of claims 1 through 6,
   characterized in that the linear antenna conductor (12) is situated on a surface (22-27) of the substrate (2-4) and the common antenna foot point (13) is situated on a different surface (22-27) of the same or of a different substrate (2-4), wherein the linear antenna conductor (12) and the common antenna foot point (13) are electrically conductively connected to each other via a second connection conductor (34).
8. Antenna structure (1) according to one of claims 1 through 7,
   characterized in that the linear antenna conductor (12) comprises a conductor path (35) made of a metallic printing paste, or of a wire (18).
9. Antenna structure (1) according to one of claims 1 through 8,
   characterized in that at least one of the conductors, selected from the coupling electrode (10), the first connection conductor (33), and the second connection conductor (34), leads to the edge (5) of the substrate (2-4) and is configured as a strip-shaped flat conductor with a tapering width in the region of the edge (5).
10. Use of an antenna structure (1) according to one of claims 1 through 9 as a built-in part in furniture, devices, and buildings, as well as in means of transportation for travel on land, in the air, or on water, in particular in motor vehicles, for example, as a windshield, a rear window, a side window, and/or a glass roof.

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