DE102015002442B3 - Mobile radio antenna and associated method for its production - Google Patents

Abstract

An improved mobile radio antenna and an associated improved method for the production thereof are characterized by the following features: the conductive surface structure consists of a composite film 41, the composite film 41 comprises at least one plastic carrier layer 55, 59 and the metal foil or film applied thereon layer (57), and - the composite film (41) is glued on the outer surface or outer skin (19 ') of the radome (5) associated with the mobile radio antenna.

Description

The invention relates to a mobile radio antenna and an associated method for producing a mobile radio antenna.

Cellular antennas for base stations usually have a vertically extending conductive reflector, which may also be provided with extending in the longitudinal or vertical direction and offset from the center to the outside webs, edge boundaries, etc., which are aligned at an angle or perpendicular to the reflector plane. In front of the reflector, a plurality of vertically offset radiators, radiator elements or radiator groups are arranged, which can transmit and / or receive, for example, in a polarization plane or in two mutually perpendicular polarization planes.

Often the dual polarized radiators are at an angle of +45 deg. or -45 deg. aligned with the vertical (or horizontal), which is why we speak of X-polarization emitters.

The radiators, radiator elements and radiator groups can be arranged side by side in one or more columns. However, such antenna arrays, which have several columns next to one another, generally also have a common reflector or a common reflector plate.

Suitable emitter elements are all conceivable emitters, for example single-polarized or dual-polarized emitters, dipole emitters or dipole-like emitters, patch emitters, etc. With regard to the various types of emitters used, reference is made, by way of example only, to the following prior publications, namely DE 197 22 742 A1 . DE 196 27 015 A1 . US 5,710,569 A . WO 00/39 894 A1 or DE 101 50 150 A1 ,

Such antenna arrangements are usually housed in a radome, which serves to protect the radiator from the weather. The radome itself is permeable to electromagnetic waves and usually consists of a glass fiber reinforced plastic.

In widely used mobile radio antennas, the radome is generally designed in the circumferential direction as a closed overall housing, on whose top and bottom end corresponding cover caps can be placed. Corresponding cable connections for the HF signals and / or for controlling antenna components (for example a downtilt angle) can be connected to the underside of the antenna and / or also to the rear side of the antenna.

It is known that mobile radio antennas are usually designed for radiation only in a specific sector, for example for a sector of 120 °, 30 °. or 180 deg. 30 deg. etc. Often, therefore, a high return loss is desired, which should be greater than 20 dB, often even greater than 25 dB or even greater than 30 dB.

In order to achieve a better re-damping is already housed in a previously known and housed in a radome mobile antenna (wherein the entire antenna device including the reflector and the radiators based thereon, radiator elements or radiator groups are housed in the circumferentially closed radome) at a distance behind the back of the Radoms an additional sheet metal has been mounted. As a result, a "double reflector" is formed as it were, whereby the rear damping is improved.

Such a structure is for example from the DE 102 17 330 B4 known. To improve the antenna return loss (FTBR, ie front-to-back ratio) and the side attenuation (FTSR, ie front-to-side ratio) and thus to achieve improved suppression of side lobes and to better protect the spotlights, is on the back of a reflector at a distance to a second reflector and in a further embodiment, again at a distance from the second reflector behind this provided a third reflector. All reflectors have side bars, which rise from the respective reflector plane in the beam direction to the front. This results in a shell structure, wherein the outermost reflector with its side bars the middle reflector and this surrounds the actual, the radiator-bearing reflector not only on the back, but also laterally and shields.

In the JP 2005-033404 A1 a radome for an antenna is shown, with reflector side bars rising from the radome back in the beam direction. The reflector side bars are provided as plate-shaped strips on the outer skin of the radome. These plates can also be arranged at a certain distance from the rear wall of the radome on the side wall regions of the radome. It is even possible that these strip-shaped plates are attached to the transition region from the side surfaces of the radome to the front area, for which they must be slightly curved in cross-section, since here the radome usually passes over an arc section from the side wall portion to the front portion.

Finally, in the DE 10 2005 005 781 A1 or in the EP 1 689 022 A1 has been proposed, in addition to provide a reflector in the form of a conductive surface structure, which is incorporated in the rear wall of the radome and / or is located in the rear wall of the radome in a mobile radio antenna with a reflector housed in a radome housed.

Characterized in that the conductive surface structure according to the DE 10 2005 005 781 A1 or the EP 1 689 022 A1 is incorporated into the material of the radome, the radome should be easier (compared with that of the prior art, in which reflector panels are mounted separately in the distance to the radome separately). In addition, the incorporated in the radome material reflector should be better protected. In particular, compared to previously known solutions in which, for example, reflector devices would be adhered to the wheel material, the danger is to be counteracted that solve these reflectors at high heat again from the wheel material.

It is in the DE 10 2005 005 781 A1 It has also been proposed to provide the mentioned conductive surface structures in the wheel material not only on the back side and / or in the side wall sections of the radome but additionally or alternatively also in the front side of the radome.

According to the prior art, the incorporated in the wheel material conductive surface structure, for example, from a conductive fabric structure, in particular a form of a wire mesh structure, a hole structure, a grid structure, a line grid structure or a metal foil consisting at least one side and preferably on both sides with a paper or paper comprehensive layer is laminated.

From the pre-publication US 2005/0062673 A1 As is known, an apparatus for improving the antenna radiation behavior, which comprises a plurality of scattering structures of a structured, conductive layer on the radome of a base station sector antenna. The scattering structures are applied as a conductive layer in the form of a plurality of strips by means of an adhesive layer on the outside or front of the radome. The scattering structures consist of a patterned, conductive layer of metal, which is provided on the opposite side of the radome with a protective layer. The metal layer itself is adhered by means of an adhesive layer on the outer skin of the radome.

The US 2008/0010809 A1 describes a method for producing a sticker, with an antenna which can be glued in the sense of a radiation structure. In the method, a copper foil is temporarily glued as a metal foil to a removable film or release film, coated and punched or cut out of it a pattern in the sense of a structure. The thus structured copper foil is then glued to a Mylar layer in the sense of a plastic film, the release film is removed, an adhesive is applied to the Mylar layer and the release film is applied again. After cutting the film thus produced, it creates a sticker with an antenna.

The object of the present invention is to provide a further improved mobile radio antenna as well as an improved radome suitable for this purpose and a method for producing a mobile radio antenna improved in this way.

The object is achieved according to the invention with respect to the mobile radio antenna according to the claim 1, with respect to the method for producing a mobile antenna according to the claim 18 and with respect to a mobile antenna according to the invention according to the features specified in claim 22. Advantageous embodiments of the invention are specified in the subclaims.

In the context of the present invention, it is possible to realize not only an improvement in the radiation property of a mobile radio antenna, for example by the improved antenna return loss or improved side attenuation, but also an intermodulation suppression, which in the prior art, for example, to the antenna leading power cable (power cable) are caused.

In the same way, by incorporating appropriate radiation or slot structures or the like, for example in the side wall sections of the radome and / or in the front side region of the radome, the radiation pattern can be specifically acted upon.

In contrast to the previously known solutions in which, for example, a second or third reflector (sub-reflector) was mounted behind the antenna radome, a much smaller installation space is required within the scope of the invention.

Also in the solution according to the DE 10 2005 005 781 A1 or the EP 1 689 022 A1 Only a small space is required because the conductive surface structure is incorporated in particular in the form of a grid and / or hole structure in the wheel material itself. However, it has been found that such a construction consuming and thus cost-intensive, especially labor-intensive and time-consuming in terms of production and also inflexible in the individual design.

In the context of the present invention, therefore, only a comparatively thin composite film is glued to the outer skin of a radome, preferably glued over its entire surface. This process is easy and inexpensive to perform. By sticking such a composite foil on the outside of the radome, d. H. On the outer skin of the radome, a second, the shield improving rear reflector can be formed in a simple manner, as well as corresponding second reflector side webs, when the metal foil is provided in the side region or in the side region of the radome. It proves to be particularly positive in the context of the invention that the side area also can be adjusted individually, which also applies to the dimensioning. In other words, the corresponding composite foil in the desired width can be provided correspondingly adapted to the radome.

The composite film itself is ultimately constructed so that initially an outer plastic carrier layer is provided, on which the Radom side facing a metal layer follows, in turn, is provided following another plastic carrier layer, which is then glued to the outer skin of the radome. Thus, the composite film is at least three-layered or three-layered and preferably also comprises at least one further adhesive layer on the plastic carrier layer, with which the composite film is ultimately adhered to the outer skin of the radome.

In other words, therefore, the composite film adhered or adhered to the radome has a multilayer structure and comprises a metal layer, wherein a carrier layer is provided on each side of this metal layer, so that these composite films comprising at least three layers are then adhesively bonded to the outer skin of the radome by means of a hard adhesive layer can.

If additional beam-shaping, in particular passive radiation structures realized, these z. B. be formed as a single conductive surface structures on a serving as a carrier layer plastic film. But it is also possible that on a composite film, a corresponding metal layer or metal foil is provided which has certain recesses for generating passive radiation structures, such as slot recesses in the metal foil or metal layer, wherein at least one intended plastic carrier layer for the metal foil preferably passes through the entire surface, so no recesses in the plastic film material. In other words, a generally at least two or more layers of film with a corresponding metal layer or metal foil is adhered as fully as possible on the outer skin of the radome, metal surface areas are then provided for the preparation of the corresponding beam-forming structures only at certain locations or not provided at certain locations , Such metal-free structures then so surrounded by corresponding conductive metal surfaces and are formed thereby.

In a preferred embodiment of the invention, a self-adhesive composite film is used, although the adhesive layer can also be applied separately on the outside of the radome and / or on the side of the film composite to be bonded prior to bonding.

The composite film comprising the material film or material layer can have the lowest material thicknesses, for example less than 1 mm, possibly even less than 0.5 mm.

The carrier layer is preferably made of polyethylene terephthalate (PET). It is therefore a thermoplastic produced by polycondensation from the family polyester. However, the carrier film can also consist of polyethylene (PE), for example of PE-LD (LDPE), ie highly branched polymer chains with the formation of a comparatively lower density.

It proves to be particularly advantageous that in the production of the radome not only the radome itself can be produced in the sense of an extrusion or casting process, but also that the composite film production and / or attachment in a pultrusion process, ie in a pultrusion continuous on the Radom can be applied.

In summary, it can thus be stated that, within the scope of the invention, best results with regard to improved shielding and / or with regard to the production of radiator structures, in particular passive radiator structures, can be generated with the simplest means. In this case, an extremely space-saving solution is proposed, wherein the existing radome assumes the insulating and position function for the metal foil or metal foil comprehensive composite foil. This eliminates all previously required additional parts or there is an additional gain in space within the antenna, if previously separate additional expansive Schirmungsteile have been used in the prior art. In contrast to the conductive surface structures incorporated in the wheel material itself, the solution according to the invention can be implemented much more simply and effectively. Above all, that the film easily at all desired regions can be adhered as far as desired over the entire length of the radome and also in the side areas, compared to conventional solutions, even with respect to the incorporated in the radome material conductive surface structure much easier especially optimal shielding in the rear and / or side region of the radome achieve, which not only generally improved antenna attenuation, improve the side attenuation, a lighter radiation waveform, but above all an optimal shielding, for example, to a so-called Remote Radio Head (RRH) can be realized, as he often today between the back of the radome and, for example, an antenna mast is provided separately.

In the context of the invention, an improved intermodulation suppression can be achieved by the composite film according to the invention which has to be optimally applied and has optimal shielding, for example also with respect to a power cable leading to the antenna (power cables). The same applies in principle also with respect to a non-intermodulation cable which runs behind the antenna or with respect to a so-called remote radio head (RRH), which is usually mounted behind the antenna on a mast. Within the scope of the invention, however, it is also possible to generally reduce and prevent the negative influences on the antenna, which are exerted, for example, by a mast carrying the antenna, by a cable leading to the antenna, steel cables mechanically fixed by the antenna. In other words, the intermodulation suppression and thus the passive intermodulation strength (= reduction or suppression of passive intermodulation) can be significantly improved.

It has also been found to be positive that the composite film can be cut to any size and placed for different applications or antenna designs. It is also possible to choose from a selection of different slides, each optimized for the specific application.

In a particularly preferred embodiment, the radiator structures are designed in the form of passive radiating structures in the manner of frequency-selective surfaces. These are preferably arranged periodically on the radome, i. H. especially periodically positioned in the longitudinal direction of the radome. In this case, these frequency-selective surfaces can be realized as preferred passive radiation structures, preferably in the form of periodically arranged dipoles or periodically arranged slots (which then form magnetic dipoles). The difference is in the reflected or transmitted wave. Looking only at the transmission, a band stop filter can be realized with the electric dipoles. If only the reflection is considered, then a bandpass filter can be generated with the magnetic dipoles.

On the frequency-selective surfaces can be a variety of shape designs, d. H. Select different structural forms. Preference is given to forms, for example in the form of the so-called Jerusalem cross or a hexagon loop.

The invention will be explained in more detail by way of examples. In detail:

1 a schematic perspective view of a mobile radio antenna with a radome, which is attached to a mast;

2 3 shows a schematic perspective sectional view through an antenna with a radome according to the invention with a composite foil adhered to the outer skin of the rear side and a partial region of the side wall sections of the radome and comprising a metal layer;

3 a cross section through a radome according to the invention, as it is part of a mobile radio antenna;

4 a partial cross-sectional representation by a glued on the back of a radome and a metal layer comprehensive not belonging to the invention composite film;

5 : one too 4 modified inventive embodiment;

6 a further cross-sectional view through a radome comparable to the sectional view according to 3 ;

7a and 7b in part: representations on the composite film adhered to the outer skin of a radome, comprising metal-free sections, leaving electrically conductive structures behind;

8a and 8b : corresponding representations too 7a and 7b However, wherein the corresponding preferably passive radiation structures are formed by cut-outs in the metal foil area, which is designed metal-free;

9a FIG. 2: a representation of passive radiation structures on the radome using periodic electrical dipoles; FIG.

9b : A representation of passive radiation structures on the radome using periodic magnetic dipoles;

10a to 10c : a first group A of rotationally symmetric passive radiation structures;

11a to 11c a second group B of passive radiation structures in loop form, bounded by an interior space;

12a to 12c : a third group C of passive radiation structures with full-surface interior;

13 : a representation of periodically arranged passive radiation structures which begin in the sidewall region of the radome and extend over the curvature region into the adjoining edge region of the front side;

13a : an enlarged detail of a so-called Jerusalem Cross as an example of the passive radiation structure;

14 : one too 14 modified embodiment using periodically arranged hexagonal loop structures (hexagon);

14a : an enlarged detail of the hexagonal passive conductive structure as shown in FIG 15 is used; and

15a and 15b Two further simplified images of basically possible passive radiation structures.

In 1 is a schematic representation of a mobile radio antenna 1 shown, which belongs for example to a base station. The mobile radio antenna 1 is z. B. over a mast 2 kept and adjusted. The mobile radio antenna 1 inside includes a in 1 not yet visible reflector 3 in front of which, as a rule, a multiplicity of radiators, for example dipole radiators, patch radiators, etc., are arranged in the vertical direction at an offset from one another.

The radiators may be any suitable radiator, radiator elements or radiator groups, as these basically, for example, from the Vorveröffentlichungen DE 197 22 742 A1 . DE 196 27 015 A1 . US 5,710,569 A . WO 00/39 894 A1 or DE 101 50 150 A1 are known.

The radiators, radiator elements or radiator groups are below a radome 5 housed protected, the Radom 5 usually made as a one-piece body, which is closed in the circumferential direction and a rather bulbous curved front 7 , Sidewall sections 10 and a usually rather flat back 9 includes. At the top is an upper cap 11 attachable and attachable and at the bottom of a corresponding lower end cap 13 ( 1 ). The lower end cap 13 However, there is often also a metal flange on which the electrical connections for the radiators or other control devices located in the antenna are provided in order, for example, to set a downtilt angle, etc. differently. In 1 are cables 8th drawn to the connections at the bottom of the antenna cover. In this respect, reference is made to known solutions.

In 2 Furthermore, a perspective excerpted sectional view of the mobile radio antenna is to be seen, with a circumferentially closed radome, within which a conductive reflector 3 is housed. This usually consists of metal or sheet metal. The reflector 3 can also have two reflector side wall sections or sidewall webs 5a (Reflector sidewall webs), which extend in the longitudinal direction and thus usually with a corresponding orientation of the antenna in the vertical direction and thereby can be placed perpendicular or at a different angle to the reflector plane RE.

In the longitudinal direction of the reflector, the radiators which are suitable or desired for the mobile radio range are at a distance from one another 15 arranged, which can radiate in a plane of polarization or in two planes of polarization, ie send and receive. The radiator z. B. in a single band or in a dual or multi-band operation and / or receive.

In 2 is partially in perspective a single dual polarized radiator 15 seen from a dipole square 15 ' exists and has an associated carrier 17 on the reflector 3 is mounted.

As in particular from the cross-sectional view according to 3 It can be seen on the outside 19 the radome, ie the outer skin 19 ' now over the entire surface or in partial surface areas, the mentioned conductive surface structure 39 in the form of a composite foil 41 be applied, which comprises a metal layer or foil. The corresponding composite foil 41 is in the cross-sectional view in 3 indicated by dashed lines.

As in the cross-sectional view according to 3 Also indicated is the mentioned composite foil 41 with the included metal layer or Metal foil, for example, all over the back 9 and / or on the sidewall sections 10 the radome 5 at least in a partial height range H1 based on the total height or total thickness H (starting from the rear side 9 the radome), as shown in the cross-sectional view according to 3 is indicated by dashed lines. Due to the attachment of the composite foil on the outside 19 There is no delay on the radome here. In addition, the metal structures are optimally placed in the composite film, since the composite film can also be configured arbitrarily with respect to their color design, there is also the advantage that the visual impression of the antenna deliberately changed by a desired design and / or by a preferred cut of the film can be.

Based on 4 is a possible construction of the in 3 shown excerpt X in enlarged excerpts, the fragmentary not belonging to the invention composite film 41 in its basic structure reflects how it is on the back 51 the radome 5 is glued on.

Here, in the cross-section, the profile is 5 ' the radome 5 For example, to see how it z. B. on the back side 9 the radome 5 is trained. Glued on is the mentioned composite film 41 The outboard, so opposite to the Radom 5 a plastic carrier layer 55 , then following the electrically conductive metal layer 57 and then an adhesive layer 61 includes, over which the composite film thus formed 41 on the material or the profile 5 ' the radome 5 is glued on.

Based on the cross-sectional view according to 5 with respect to an embodiment of the invention (wherein 5 the detail Y in 3 enlarged) shows that the structure can also be such that coming from the outside towards the outer skin 19 or surface 19 ' the radome 5 the composite foil 41 is constructed so that first an outer plastic carrier layer 55 is provided on which the the Radom 5 facing side a metal layer 57 follows, in turn, another plastic carrier layer 59 following is provided, which then on the mentioned adhesive layer 61 on the outside surface 19 ' the radome 5 is glued on.

The conductive metal layer 57 may for example consist of a copper layer, a brass layer, an aluminum layer or a tin or zinc layer. Preferably, the metal layer or metal foil 57 made of a material that does not contain steel or iron, ie is made of a stainless material.

The plastic carrier layer 55 . 57 , in particular the outer plastic carrier layer 55 , For example, may consist of polyethylene terephthalate (PET, PETP), ie from a thermoplastic produced by polycondensation, preferably from the family of polyesters.

PE-LD (LDPE):

stark verzweigte Polymerketten mit geringer Dichte (”LD” steht für ”low density”);

PE-HD (HDPE):

schwach verzweigte Polymerketten (”HD” steht für ”high density”);

PE-LLD (LLDPE):

lineares Polyethylen niederer Dichte, dessen Polymermolekül nur kurze Verzweigungen aufweist (”LLD” steht für ”linear low density”)

PE-HMW:

hochmolekulares Polyethylen (”HMW” steht für high molecular weight”);

PE-UHMW:

ultrahochmolekulares HDPE mit einer mittleren Molmasse (”UHMW” steht für ”ultra high molecular weight”).

The second plastic carrier layer, which may be closer to the wheel material and optionally provided, may be made, for example, of polyethylene (PE), that is to say of a thermoplastic polymer produced by chain polymerization of ethene. In this case, preference is given to using PE types such as, for example, PE-LD (LDPE), although other PE types are also suitable, for example

PE-LD (LDPE):

highly branched polymer chains with low density ("LD" stands for "low density");

PE-HD (HDPE):

weakly branched polymer chains ("HD" stands for "high density");

PE-LLD (LLDPE):

linear low-density polyethylene whose polymer molecule has only short branches ("LLD" stands for "linear low density")

PE-HMW:

high molecular weight polyethylene ("HMW" stands for high molecular weight);

PE-UHMW:

ultra high molecular weight HDPE with an average molecular weight ("UHMW" stands for "ultra high molecular weight").

It can therefore be seen that the composite film is basically a two-layered or three-layered film, but preferred from home with a further layer, namely the adhesive layer 61 is provided. In that regard, can also of a self-adhesive composite film 41 to be spoken.

Due to the manufacturing process, an adhesion promoter layer can still be provided between the respectively mentioned plastic carrier layer and the metal layer, which, however, is significantly thinner in relation to the individual plastic carrier layer or metal layer.

The entire structure of the composite film thus formed 41 may be such that its thickness is less than 1 mm, in particular less than 0.9 mm, 0.8 mm, 0.7 mm, 0.6 mm, 0.5 mm, 0.4 mm, 0.3 mm or 0.2 mm.

In the embodiment shown according to 2 is the mentioned, the metal layer 57 comprehensive composite foil 41 to the side wall area 10 the radome 5 running on the outer skin 19 ' glued to the radome. The adhesive layer ends here z. B. approximately at a height relative to the reflector plane RE within the radome 5 mounted reflector 3 , for example, the location of the free web edges 3'a the reflector side bars 3a to come to rest. However, the composite film can end even greater or lesser distance to the reflector plane RE, that deviating from the height of the free-ending web edges 3'a the side bars 3a of the reflector 3 ,

It is also possible, for example, as shown by the cross-sectional view in accordance with 6 shown is that the metal foil or metal layer 57 comprehensive composite foil 41 even larger areas of the sidewall sections 10 The radome is covered on the outer skin or even glued circumferentially around the entire radome around.

In addition, it should be emphasized that in the context of the invention, a targeted application of the composite film is possible, d. H. an exact placement and alignment, ie in preselected relative position to the radiator elements in the antenna. In other words, the corresponding structures in the foil can be placed exactly where they can interact optimally with the radiators located below the radome.

Furthermore, the radiator elements and / or the composite film 41 with or without radiant structures discussed in more detail below may be arranged asymmetrically and / or only on one side of the radome or, as a rule, provided symmetrically on both sides of the radome.

The explained composite foil 41 may preferably be adhered during a pultrusion process (extrusion process) in the corresponding production of the radome with integrated. The advantage of such a pultrusion process is that thereby a radome with glued composite foil 41 almost in an endless process can be produced. Post-processing steps or additional further work steps are also avoided.

However, it should be noted that the film application can also take place in a further process step. In this case, the composite film to be stuck would 41 cut in certain sections in a suitable manner and applied, for example via a rolling mechanism on the radome, ie glued. This is again preferably a self-adhesive or self-adhesive composite film 41 , It is also possible that the outer skin or outer surface 19 ' the radome 5 is first provided with an adhesive layer (for example, on the outer skin 19 ' the radome an adhesive layer is sprayed), before then the plastic-metal foil 41 is glued on. Additionally or alternatively, an adhesive or adhesive layer on the side of the composite film 41 first applied, with which the composite foil 41 then on the outer skin 19 ' the radome 5 should be glued.

Another advantage of a so-formed plastic-metal foil composite 41 is that the mainly external plastic carrier layer 55 not only transparent, but also colored. It would even be possible to apply certain print images. As a result, the exterior design of a radome could in addition with minimal effort z. B. differently colored or provided with any patterns, printing contours, etc. It could also be printed advertising. In addition, the individual mobile radio antennas could also be provided according to the appearance of the individual mobile operators with their logos or typically used originating function triggering colors.

It has already been explained, with reference to 6 in that the mentioned composite foil can, for example, surround the entire radome in the circumferential direction, ie covers it.

Especially in this latter case, when the composite film 41 around the entire radome 5 glued around or for example only on the front 7 and / or on the sidewall sections 10 is provided, the composite film with the at least one plastic carrier layer 55 or for example the at least two plastic carrier layers 55 and 57 In addition, no full-surface closed metal layer or metal foil 57 but only metal layer sections or structures 157 , These metal layer sections or structures 157 could, as based on 7a and 7b reproduced, for example, rectangular or cross-shaped metal structures 157 have, that of a metal surface-free area 158 are surrounded. As a result, slot-shaped or cross-slot-shaped radiator structures, in particular passive radiator structures, can be realized, especially on the front side of the radome. But also in the sidewall sections 10 Slot-shaped radiator structures could preferably be formed thereby, which serve a targeted beam shaping.

In the partial by means of 8a and 8b variant shown is the composite film 41 so constructed that the metal layer 57 is preferably formed almost almost full surface, but that then in this full-surface metal layer recesses 157 ' are formed, for example, in turn, slot-shaped or cross-slot-shaped recess structures 157 ' , about which also certain passive radiator structures can be generated. Such passive radiator structures are particularly suitable for use in the sidewall area 10 the radome 5 ,

So while the metal foil or metal layer 57 the composite foil 41 especially on the back 9 and / or in sidewall areas 10 the radome 5 is provided in order to achieve optimum shielding, the above-mentioned electrically conductive surface structures 157 , which are relatively small area based on the metal-free zurückbelassenen sections 158 the composite film, preferably on the top or front 7 the radome 5 be provided. Slot-shaped structures preferably also in the form of recesses 157 ' (Which are at least formed only in the metallic layer, but which can also be formed in the entire composite film, so all layers of the composite film prevail) may preferably in the side wall portions 10 the radome are implemented.

The following is intended to explain how, within the scope of the inventive design of the modular radio antenna or the design of the radome according to the invention, further or alternatively other structures may be provided which ultimately serve for beam shaping.

In this context, already with reference to the previous 7a to 8b Examples have been shown, such as the mentioned composite foil 41 can be used to form frequency-selective structures and / or surfaces (FSS), whereby antenna parameters of a base station antenna, for example, can be improved. In this case, conductive periodic structures are preferably provided. Based on 7a to 8b only individual structures have been shown, which are usually arranged periodically repeating in the longitudinal direction of the radome, in particular in the sidewall region 10 adjacent to the lateral edge of the front 7 or, for example, additionally or alternatively in the immediate transition region from the sidewall region 10 to the front 7 So in any area where the radome usually has a greater curvature.

• • periodisch angeordneten Dipolen, und
• • periodisch angeordneten Schlitzen (magnetische Dipole).

In the realization of particular frequency-selective structures and / or surfaces (FSS) are - what already with reference to the 7a . 7b in contrast to 8a . 8b explained in principle - to distinguish two different configurations. It is possible that the construction and the use of

• • periodically arranged dipoles, and
• • periodically arranged slots (magnetic dipoles).

The difference between the two variants consists in the reflected wave and the transmitted wave.

Looking at the transmission, a band stop filter can be created with the electric dipoles and a band pass filter with the magnetic dipoles. This is only in principle to the attached 9a and 9b referenced, the 9a schematically the use of periodic electric dipoles (ie conductive structures 157 ) and the 9b the use of periodic magnetic dipoles (ie slits 157 ' ) shows.

The optimal size of the structures to be used depends on the one hand on the frequency (operating frequency of the corresponding mobile radio antenna) and the form of the structures used.

The following are based on the 10a to 12c different examples of possible passive radiation structures explained. By selecting the structure, a specific narrowband or broadband radiator shaping can be achieved.

Based on 10a to 10c In principle, a first group of frequency-selective structures is shown, all of which have a common center Z, insofar as they are also referred to as a center-connected structural form A.

Based on 11a to 11c For example, a second group of frequency-selective structure form B, referred to as loop structures, is shown as having an interior space 45 circumscribe. These so-called "loop types" are generally smaller than the above-mentioned "A-type"("center-connectedtypes") and have the further advantage that they can be mounted as a group to each other. These structural shapes B are typically dimensioned such that the circumference of this structural shape is preferably in a certain relation to the wavelength, preferably to the average operating wavelength of the frequency band to be transmitted, for example a multiple of λ / 2 with respect to the operating wavelength or the average operating wavelength.

Based on 12a to 12c are surface structures C reproduced, in the manner of a regular n-polygonal or For example, in circular or disc shape, so that the entire inner surface is closed over the entire surface.

Furthermore, variants are possible which relate to combinations of the abovementioned structural forms A, B and / or C, with further modifications and designs, which may thus be partially or completely enclosed, which are partially double-walled, etc. Furthermore, it is possible that the mentioned hybrid forms of the different structural forms can also be arranged one inside the other or interleaved, so that for different frequency ranges a respectively desired different beam shaping can be achieved.

From the illustrated structural forms, it can be seen that many of these structural forms mentioned and shown have a point-symmetrical structure for the formation of frequency-selective surfaces FSS, that is to say with respect to a central axis Z1 passing centrally through the structural form. In this case, the first group A of the frequency-selective surface structure is rotationally symmetrical, with a 90 ° or 120 ° repetition period.

The hexagonal structures not only have a 120 ° rotational symmetry but a 60 ° rotational symmetry. The circular or disk-shaped structures are point-symmetrical, that is designed as a whole rotationally symmetrical.

Based on 13 the construction of a radome will be explained in greater detail, wherein in the illustration according to 13 in the transition area from the sidewall area 10 in the adjacent front area 7 the radome 5 As a frequency-selective surface structure FSS, for example, a so-called Jerusalem cross is used, which is offset from one another with a periodic spacing in the longitudinal direction of the radome. It is therefore that representation that the 10c corresponds and based on 13a is reproduced enlarged in individual representations.

It can be seen that each one axis 46 of the Jerusalem Cross in the longitudinal direction of the radome and the axis running through 90 ° transversely thereto 47 exactly transverse and thus perpendicular to the longitudinal direction of the radome. At the respective ends of this cross-shaped structure is in each case a short crossbar 48 educated.

Based on 14 a different example is shown, using a hexagonal loop structure, as shown by 11c on the one hand and in an enlarged view on the basis of 14a (the lower portion of the hexagonal loop structure may be limited to the side surface or may be folded over to the back of the radome).

This hexagonal structure (hexagon) is again in the longitudinal direction at the transition region of the side wall 10 to the adjacent front 9 over the edge-like curvature area formed therebetween 12 in the longitudinal direction of the radome 5 formed, wherein the arrangement of this honeycomb hexagonal loop structure has been made so that the individual periodically arranged frequency-selective surface structures FFS are arranged not only in the longitudinal direction L of the radome, but in each case successively with slight lateral offset, as shown 15 can be seen. In other words, in each case a leading and a trailing hexagon is arranged to a hexagon arranged therebetween so that the leading and the trailing hexagon structure form a 120 ° angle to each other.

The corresponding structures 157 may be formed as conductive structures in the composite film 41 ie on the at least one plastic carrier layer 55 . 59 are formed. These conductive structures are thus located in a surrounding area on the at least one plastic carrier layer 55 . 59 , which is otherwise formed completely or largely free of metal film.

It is also possible that the structure 157 ' as mentioned, is not designed as electrically conductive and thus periodically electric dipoles, but as slot-shaped recesses 157 ' and thus as periodic magnetic dipoles. In this case, the metal layer would 57 also be present in the transition region shown from the side wall region to the adjacent front region of the radome, in which case the corresponding structures described in FIG 13 or 14 as slot cutouts 157 ' are provided.

Furthermore, the structures mentioned can also be packed relatively tightly in order to increase the filtering effect. Thus, for example, the aforementioned cross structures can also be positioned in a very approximate position relative to one another without touching each other. In particular, even when using the so-called Jerusalem cross as a structure, the respective structures can be arranged by offset so as to achieve the above-mentioned higher arrangement density.

The size of the structures including the line width can be varied within wide ranges, especially in adaptation to the frequency range of the mobile radio antenna used.

Regarding the Jerusalem Cross according to 14a values for the individual metal surface sections are reproduced below, which may vary, for example, between the following values:
JK1: 10 mm to 100 mm, in particular 20 mm to 80 mm or 30 mm to 60 mm, in particular by 40 mm.
JK2: 10 mm to 100 mm, in particular 20 mm to 80 mm or 30 mm to 60 mm, in particular by 40 mm.
JK3: 0.5 mm to 40 mm, in particular 5 mm to 30 mm, in particular 8 mm to 20 mm, in particular 10 mm to 14 mm. In other words, the lower limit with respect to this measure may be set so that the corresponding dimension is at least 0.5 mm and preferably more than 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 7.5 mm, 10 mm, 12 , 5 mm, 15 mm, 17.5 mm, 20 mm, 22.5 mm, 25 mm, 27.5 mm, 30 mm. Conversely, favorable applications result when the corresponding dimension is less than 40 mm, in particular less than 37.5 mm, 35 mm, 32.5 mm, 30 mm, 27.5 mm, 25 mm, 22.5 mm, 20 mm , 17.5 mm, 15 mm, 12.5 mm, 10 mm.

Regarding the hexagonal loop structure as shown 15a For example, a hexagonal frequency selective surface structure FSS may be used which has a diameter between two parallel opposite sides with the following values:
HS1: 10 mm to 200 mm, 70 mm to 120 mm, in particular 80 mm to 100 mm. In other words, the dimension may preferably be more than 10 mm, in particular more than 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, 65 mm, 70 mm , 75 mm, 80 mm. On the other hand, preferred dimensions should be less than 80 mm, 75 mm, 70 mm, 65 mm, 60 mm, 55 mm, 50 mm, 45 mm, 40 mm, 35 mm, 30 mm, 25 mm, 20 mm.
HS2: 1 mm to 40 mm, in particular 5 mm to 30 mm. In other words, the corresponding dimension for HS2 should preferably be more than 2 mm, in particular more than 3 mm, 4 mm, 5 mm, 7.5 mm, 10 mm, 12.5 mm, 15 mm, 17.5 mm, 20 mm , 22.5 mm, 25 mm, 27.5 mm, 30 mm. Conversely, it has proved to be favorable if the corresponding dimension is preferably smaller than 35 mm, 32.5 mm, 30 mm, 27.5 mm, 25 mm, 22.5 mm, 20 mm, 17.5 mm, 15 mm , 12.5 mm, 10 mm, 7.5 mm, 5 mm, 2.5 mm.
HS3: 0.5 mm to 20 mm, in particular 0.8 mm to 15 mm or 1 mm to 1.6 mm. In other words, the measure for HS3 should preferably be greater than 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 7.5 mm, 10 mm, 12.5 mm, 15 mm, 17.5 mm. Then it is advantageous if the corresponding dimension is smaller than 17, 5 mm, 15 mm, 12.5 mm, 10 mm, 9 mm, 8 mm, 7 mm, 6 mm, 5 mm, 4 mm, 3 mm, 2 mm.
HS4: the gap distance HS4 to an adjacent hexagon loop structure may preferably vary between 3 mm and 20 mm, in particular 8 mm and 15 mm, preferably 10 mm to 14 mm.

The structures explained are as mentioned in the composite film 41 formed, so that the composite film, as already explained with reference to the other embodiments, in a pultrusion process (Strangziehprozess) or separately subsequently, for example, preferably using a rolling mechanism on the surface or outside of the radome, targeted in certain selectable definable areas of the outside of the radome or surrounding the radome over its entire surface.

Based on 15a and 15b is merely exemplified yet another simplified variant of a passive radiation structure reproduced based on 15a in the form of a simple strip (rectangular strip) and based on 15b in the form of such a rectangular strip, at whose opposite ends in each case a transverse bar is provided. From two such, based on 15b shown and rotated by 90 ° to each other arranged structures is ultimately the so-called., Based on 13a Jerusalem Cross shown made.

Finally, it should also be pointed out that the mentioned composite foil can comprise and have not only one metal layer or metal foil but a plurality of metal layers, ie a plurality of metal foils, which may optionally be provided with the structures explained, also with different structures. This composite foil with the at least two or more metal layers or foils with the structures optionally provided thereon or also provided differently may, for example, be arranged offset relative to one another.

Finally, the attachment of the composite film is also possible on the radome such that, for example, on the back side and / or a part of the side wall regions, the composite film with the at least one metal foil or metal layer is applied more or less over the whole surface, and here acts as a subreflector, and that others Parts of the composite film are formed with the mentioned structures in order to influence the beam shape accordingly. In other words, mixed forms are possible, which are realized on a radome. For example, a common composite film may be provided, which is formed over the entire surface, especially in the rear region of the radome and in parts of the side region, and / or is provided with corresponding structures in certain side wall regions or on the front side. Any mixed forms are conceivable here.

The mentioned invention has been explained with reference to a composite film which preferably always has at least one plastic carrier layer. However, it should also be mentioned that it is quite possible to always use a pure metal foil instead of the mentioned composite foil, which is applied, in particular glued, to the outer surface, ie the outer skin of the radome. This metal foil can also be provided with a self-adhesive adhesive layer. In that regard, all the advantages and exemplary embodiments explained are also to be understood as meaning that instead of the composite film comprising one or more plastic carrier layers 41 always only one metal foil without additional plastic carrier layers and foils is used or provided.

Instead of the adhesive layer used, an adhesive layer can generally be used in such a way that allows in any other way to apply the composite film or the metal foil on the outer surface of the radome to anchor and firmly fixed on it.

Claims (22)

Mobile radio antenna with the following features - with a reflector ( 3 ), in front of which one or more radiators ( 15 ) are arranged, - with a the emitters ( 15 ) and the reflector ( 3 ) surrounding radome ( 5 ), where the radome ( 5 ) a front page ( 7 ), two side wall sections ( 10 ) and a back ( 9 ), - having a conductive surface structure, which in the region of the rear wall ( 9 ) and / or the one or both side wall sections ( 10 ) and / or the front ( 7 ) of the radome ( 5 ), wherein the electrically conductive surface structure comprises a metal foil or layer ( 57 ), - the electrically conductive surface structure is on the Radom ( 5 ) provided with an outer layer, and characterized by the following further features - the conductive surface structure consists of a composite film ( 41 ), - the composite foil ( 41 ) comprises two plastic carrier layers ( 55 . 59 ) and interposed a metal foil or layer ( 57 ), - the one plastic carrier layer ( 55 ) is arranged outboard as outer layer, whereas the other the Radom ( 3 ) facing plastic carrier layer ( 59 ) by means of an adhesive layer ( 61 ) on the outer surface or outer skin ( 19 ' ) of the radome ( 5 ) is glued. Mobile radio antenna according to claim 1, characterized in that the composite foil ( 41 ) as a self-adhesive composite film ( 41 ) with an associated adhesive layer ( 61 ) is trained. Mobile radio antenna according to claim 1 or 2, characterized in that the composite film ( 41 ) and on the outer surface ( 19 ' ) of the radome ( 5 ) is glued, that the plastic carrier layer ( 55 ) is arranged on the outside, to which the radome ( 3 ) facing the metal foil or layer ( 57 ) and then the adhesive layer ( 61 ) follows. Mobile radio antenna according to one of claims 1 to 3, characterized in that between the individual layers, ie the plastic carrier layer ( 55 . 61 ) and the metal layer ( 57 ) an adhesive layer is formed. Mobile radio antenna according to one of claims 1 to 4, characterized in that the outer plastic carrier layer ( 55 ) is printed, in particular with printed images in black and white or printed in color. Mobile radio antenna according to one of claims 1 to 5, characterized in that the outer plastic carrier layer ( 55 ) consists of polyethylene terephthalate (PET, PETP) or comprises this material. Mobile radio antenna according to one of claims 1 to 6, characterized in that the at least one or the second plastic carrier layer ( 55 . 57 ) consists of polyethylene (PE) or comprises polyethylene (PE), preferably in the form of highly branched polymer chains (PE-LD; LDPE). Mobile radio antenna according to one of claims 1 to 7, characterized in that the metal foil or layer ( 57 ) in the composite film ( 41 ) consists of a stainless material, and in particular comprises or consists of brass, copper, aluminum, tin or zinc. Mobile radio antenna according to one of claims 1 to 8, characterized in that the composite film ( 41 ) - only on the back ( 9 ) of the radome, or - only on the side wall sections ( 10 ) of the radome ( 5 ) or - only on the back ( 9 ) and the side wall sections ( 10 ) of the radome ( 5 ) or - in the entire circumferential direction the radome ( 5 ) is glued over the entire surface. Mobile radio antenna according to one of claims 1 to 9, characterized in that the composite film ( 41 ) over the entire length of the radome ( 5 ), or preferably at least in a range of more than 50%, 60%, 70%, 80% or 90% of the total length of the radome ( 3 ) is glued. Mobile radio antenna according to one of claims 1 to 10, characterized in that in the Composite foil ( 41 ) Radiation structures, in particular passive radiation structures ( 157 . 157 ' ) are preferably provided in the form of frequency-selective surfaces (LFSS). Mobile radio antenna according to claim 11, characterized in that the radiation structures ( 157 , FSS) in particular in the form of passive radiation structures ( 157 , FSS) are produced by structured metal surfaces, preferably in the form of dipoles, which are surrounded by metal-free regions, in particular in the form of electric dipoles. Mobile radio antenna according to claim 11, characterized in that the radiation structures ( 157 ' , FFS) in particular in the form of passive radiation structures ( 157 ' , FSS) through recesses ( 158 ) in the metal foil or layer ( 57 ) are preferably formed in the form of magnetic dipoles, in particular in the form of magnetic dipoles. Mobile radio antenna according to one of claims 11 to 13, characterized in that the passive radiation structures ( 157 . 175 ' , FSS) periodically repeating on the radome ( 5 ) are arranged, preferably in the sidewall area ( 10 ), on the front ( 7 ) and / or in the sidewall region and at least in an adjoining part of the sidewall region ( 10 ) and the adjacent front ( 7 ) of the radome ( 5 ). Mobile radio antenna according to one of claims 11 to 14, characterized in that the passive radiation structures ( 157 . 157 ' , FFS) are rotationally symmetrical or have a 90 °, 120 ° or 180 ° rotational symmetry. Mobile radio antenna according to one of claims 11 to 15, characterized in that the passive radiation structures ( 157 . 157 ' , FSS) comprise structural forms (A, B, C, D), namely in the manner of a central structural form (A), in which individual sections in a center (Z) of the passive radiation structure (A) 157 . 157 ' , FSS) and / or in the manner of a loop structure (B) with a boundary of an inner surface ( 45 ) and / or in the manner of a full-area radiation structure (C) and / or as a mixed form of the preceding structural forms (A, B, C) are formed. Mobile radio antenna according to one of Claims 11 to 16, characterized in that the passive radiation structure ( 157 . 157 ' ) is cross-shaped, preferably in the manner of a Jerusalem cross, or in the manner of an n-polygonal or regular n-polygonal with bounded inner surface ( 45 ), preferably in the form of a hexagon. Method for producing a mobile radio antenna according to one of claims 1 to 17, characterized in that at least on individual areas of the outer surface ( 19 ' ) of the radome ( 5 ) a composite foil ( 41 ) is glued, wherein a composite foil ( 41 ), the two plastic carrier layers ( 55 . 59 ) and interposed a metal foil or layer ( 57 ), wherein the radome ( 5 ) facing plastic carrier layer ( 59 ) via an adhesive layer ( 61 ) on the outer surface ( 19 ' ) of the radome ( 5 ) is glued. A method according to claim 18, characterized in that a self-adhesive composite film ( 41 ) is used. Method according to claim 18, characterized in that on the outer surface ( 19 ' ) of the radome ( 5 ) and / or on the adhesive side of the composite film ( 41 ) first an adhesive layer ( 61 ) and then the composite foil ( 41 ) on the outer surface ( 19 ' ) of the radome ( 5 ) is glued. Method according to one of claims 18 or 19, characterized in that the composite film ( 41 ) in a pultrusion process separately or together with the radome ( 5 ) or in a further process, preferably using a roller mechanism on the outer surface ( 19 ' ) of the radome ( 5 ) is glued. Mobile radio antenna produced by a method according to one of claims 18 to 21.

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