WO2006058658A1 - Dual-band mobile radio antenna - Google Patents

Abstract

The invention relates to an antenna, in particular a mobile radio antenna for operation in at least two frequency bands, comprising the following features: the antenna is equipped with several dipole transmitters (2; 3), which are located in front of a reflector (1) and transmit in two different frequency bands; the distance between the transmitter structure, the transmitter elements or the upper face (102) of the transmitter elements of at least one dipole transmitter (2) for the higher frequency band and the reflector plane (E) is at least 75 % and a maximum 150 % of the distance between a transmitter structure, a transmitter element or the upper face (103) of a transmitter element of at least one dipole transmitter (3) for the lower frequency band and the reflector plane (E); and/or the distance between the transmitter structure, transmitter elements or the upper face (102) of the transmitter elements of at least one dipole transmitter (2) for the higher frequency band and the reflector plane (E) is greater than 0.4 A and preferably less than 2 A in relation to the mid-frequency of the transmitter for the higher frequency.

Description

 TWO-BAND MOBILE ANTENNA

The invention relates to an antenna, in particular a mobile radio antenna, for operation in at least two frequency bands.

Multi-range antennas are known from the prior art which make it possible to receive or transmit radiation in at least two different frequency ranges. For example, document DE 198 23 749 A1 shows a dual-polarized multigrade antenna comprising first and second radiators. The first and second radiators radiate in different frequency ranges and comprise dual polarized dipole radiators arranged on a reflector and radiating in polarizations oriented at + 45 ° and -45 ° to the vertical. In the multigrade antenna shown in this document, the first radiators comprise cross dipoles that radiate in an upper frequency band. The radiators in the lower frequency band are dipole squares, wherein in each dipole square a cross dipole is arranged. By appropriate shaping of the reflector, the radiation properties can be However, it is not possible to simultaneously optimize the radiation characteristics of the upper and lower frequency bands.

In the above-mentioned prior publication DE 198 23 749 Al it is stated that the distance between the dipoles according to their associated frequency-dependent wavelength with respect to the reflector should not be greater than λ, preferably not greater than λ / 2 in the rule. The lower value for the distance between the dipole elements and the reflector should not be smaller than λ / 16, preferably not smaller than λ / 8.

A tulip-shaped design of a dipole radiator has also become known from WO 03/065505 A1. According to this prior publication, the distance of the rod-shaped radiator devices to the plane of the reflector should correspond to approximately 1/8 to 1/4 of an operating wavelength X, ie a region in which the corresponding dipole radiators are usually arranged in front of the reflector.

The object of the invention is therefore to provide an operating in several frequency bands antenna, which allows improved radiation properties in each frequency band.

This object is achieved by the antenna according to the independent claim. Further developments of the invention are defined in the dependent claims.

The antenna according to the invention comprises a plurality of radiators arranged in front of an electrically conductive and preferential are arranged metallic reflector, which comprises a flat surface which forms the reflector plane. The radiators each comprise one or more radiating edges and / or one or more rod-shaped elements, which represent the essential parts of the dipole radiators and are also referred to below as radiator or dipole radiator structure. The radiators are further each in a radiating plane, are arranged in the radiation edges and / or the rod-shaped elements of the radiator, each radiating plane is substantially parallel to the reflector plane or at most inclined at an angle of ± 5 ° relative to the reflector plane. In order to radiate in at least two frequency bands, first and second radiators are provided, wherein one or more of the first radiators in a common first radiating plane and one or more of the second radiators lie in a common second radiating plane and radiating in different frequency bands. The first emitters are operated here in an upper frequency band and the second emitters in a lower frequency band. The antenna according to the invention is characterized in that the distance of the first radiating plane from the reflector plane is at least 90% and at most 150% of the distance of the second radiating plane from the reflector plane.

Characterized in that the distance of the first, working in the upper frequency band radiator is approximated or greater than the distance of the second radiator, an improved radiation characteristic is achieved in particular for the radiator for the upper frequency band. By the solution according to the invention, an extremely compact design can be realized. Finally, the solution according to the invention provides further design options for the radiation pattern, that is to say for the radiation pattern shaping, and in particular for the upper frequency band. Thus, in the context of the invention, the half-value width can also be changed in a particularly favorable manner, the forward / reverse ratio can be improved, and an improved side lobe attenuation can be realized.

In a preferred embodiment of the invention, the first and second radiating planes are spaced from the reflector plane by substantially the same distance.

In order to space the first emitters operating in the upper frequency band from the reflector plane, in a particularly preferred embodiment of the invention pedestals are used which are connected to the reflector and are preferably at least partially electrically conductive. On each pedestal, a first radiator is arranged. The pedestal can be referred to as a platform or as an auxiliary reflector, which has a longitudinal and transverse extension in the longitudinal and transverse directions parallel to the reflector, which is larger than the cross section of the Sok- or the symmetrization of the associated dipole radiator.

Preferably, the pedestals on their upper side on an electrically conductive and preferably metallic podium top or platform, on each of which a first radiator is positioned. Finally, at the boundary edges of the pedestal, that is to say preferably at the upper level of the pedestal, on which the associated radiator is held over its pedestal, so-called lobes or lap-shaped extensions can be provided in the circumferential direction. These can be issued at any angle, for example at an angle of 20 °, with respect to the vertical upwards and obliquely outwards. However, these lobes can also be designed as outwardly projecting tabs lying in the plane with the pedestal surface, that is to say lying parallel to the reflector plane in other words, the pedestal area quasi widening. Likewise, the lobes can also be angled down. In other words, the lobes in any angular positions of 0 °, for example, by + 10 °, compared to the directed away from the reflector plane vertical up to 180 °, for example, 170 °, be set at an angle relative to the vertical. Finally, the flaps can only be provided at a distance from one another on the side wall sections on the pedestal, so that an open angle region remains in corner regions between two adjacent flaps. In the same way, however, the lobes can also be formed as a peripheral boundary or wall on the pedestal, over which the associated radiator rises upwards. Finally, but can be dispensed with the rag altogether.

Preferably, the lobes - if they are provided - specific length and cross dimensions in order to achieve an optimization. The spotlight standing on the pedestal can be mounted with its pedestal on top of the pedestal or the platform formed by the pedestal. Pedestal and base of the associated spotlight can also be formed in one piece, in a corresponding amount then the laterally projecting over the base conductive or metallic surface is provided, which can be referred to as podium top, plateau or auxiliary reflector.

In a further embodiment of the invention, one or more first radiators are each arranged substantially centrally in a second radiator in plan view of the reflector. Preferably, in plan view of the reflector, one or more first radiators are each arranged substantially centrally between adjacent second radiators. The arrangement in plan view thus substantially corresponds to the arrangement shown in the document DE 198 23 749 Al.

In addition to the first and the second radiation plane further radiation levels can also exist in which the ^'radiation edges and / or the rod-shaped elements of the first and / or second radiators are disposed of. In this way, the radiation field of the antenna can be further adjusted.

One or more second radiators can be, for example, dipolar squares formed from four dipoles, as shown, for example, in the already mentioned DE 198 23 749 A1. The second radiators may in particular also be cup-shaped, dual-polarized radiators, which have radiation edges or rod-shaped elements at the end remote from the reflector. In particular, the second radiators can adopt any embodiment described in document WO 03/065505 A1. Preferably, the cup-shaped radiators comprise a plurality of solid surface elements which run obliquely and / or perpendicular to the reflector plane and whose lying remote from the reflector plane boundary edge is a radiation edge. In a further preferred embodiment, in each case a first radiator is arranged in plan view on the reflector in one or more of the dipole squares and / or spherical radiators.

One or more first radiators are preferably dual-polarized cross dipoles and / or vector dipole radiators. Cross dipoles are shown, for example, in DE 198 23 749 A1, and the structure of vector dipole radiators is known from the document DE 198 60 121 A1.

In a further embodiment of the invention, the reflector has side walls which run in the longitudinal direction of the reflector and extend obliquely and / or vertically out of the reflector plane, the plurality of radiators being arranged between the side walls.

As usual, possible side walls on the reflector

(which are provided lying outside or slightly offset inwards) in a corresponding height and angled

Alignment can be provided in order to form the radiation diagram over this.

In a further embodiment of the antenna according to the invention, the center frequency of the lower frequency band is substantially half as large as the center frequency of the upper frequency band. Furthermore, a multiplicity of first and second radiators are preferably arranged in the longitudinal direction of the reflector, with a first radiator essentially centered above each second radiator and between see each pair of adjacent second emitters each substantially centrally a first emitter is arranged.

In a further embodiment, all first radiators in the first radiating plane and all second radiators in the second radiating plane are arranged.

The antenna according to the invention is preferably a mobile radio antenna whose frequency bands are in particular in the GSM, in the CDMA and / or for example in the UMTS mobile radio frequency range.

Exemplary embodiments of the invention will be described in detail below with reference to the attached figures. Show it:

Figure 1: a plan view of a section of a

Embodiment of the ^"arrival inventive antenna;

Figure 2 is a sectional view taken along the line I-I of Figure 1;

FIG. 3 shows a side view of the pedestal shown in FIG. 2 with radiator arranged thereon;

FIG. 4 shows a plan view of a detail of a second embodiment of the antenna according to the invention;

FIG. 5: a sectional view along the line II- II of Figure 4;

Figure 6: a non-sectioned side view of

Antenna according to Figure 5;

Figure 7 is a plan view of a detail of a third embodiment of the antenna according to the invention;

FIG. 8: a sectional view along the line III-

III of Figure 7; and

Figure 9: a non-sectioned side view of

Antenna according to FIG. 8.

FIG. 1 shows a plan view of a detail of a reflector sheet 1, which is referred to below as a reflector 1, which extends in the X direction. Usually, the X-length direction corresponds to the vertical direction of the antenna. The reflector comprises a substantially planar reflector base Ia, which forms the reflector plane E. The reflector plate further comprises two extending in the longitudinal or vertical direction X side walls Ib, which rise from the plane E of the reflector perpendicular or at an angle to extend and limit the reflector at the outer edge, but also be arranged offset from the outer edge further inwardly can. On this reflector 1 two types of radiators are arranged in Figure 1. The first radiator type consists of a dipole radiator 2 in the form of a vector dipole radiator. Of this type, three radiators are shown in Figure 1, which are arranged at equal intervals in the longitudinal direction X side by side and in an upper Fre- For example, in the range of 1700 MHz to 2700 MHz radiate. The structure and mode of operation of vector dipole radiators is well known from the prior art and described in particular in the publication DE 198 60 121 A1, the disclosure of which is incorporated by reference in its entirety and made part of the content of this application.

The Vektordipolstrahler each comprise a located vertically ^• right to the reflector plane E extending base 2a, which in turn consists of a balancing device 2b, which is formed by vertically in the socket 2a of extending up towards the reflector plane E, and usually to the reflector 1 aligned axial sections, for example, with a length of λ / 4, are introduced, which are remote from the reflector plane lying electrically connected to the radiator or radiator elements. The axial sections 2e extend almost to the reflector plane E, ie up to a so-called base base 2f (FIG. 2). Of ^"Therefore, the distance between the dipole and the plane is of the reflector about λ / 4 in this embodiment. At the upper end of each balancing 2b are two mutually perpendicular and parallel to the reflector plane E lines 2c provided, at each front end of the lines 2c are arranged semi-dipole components 2d, which are perpendicular to the respective line and likewise run parallel to the reflector plane E. The vector dipole radiator is constructed in electrical terms like a crossed dipole, each of which consists of two mutually perpendicular dipole halves, which in the first plane of polarization Pl or P2 (FIG. 1), such a radiator structure forming a dipole half in electrical terms is included the vector dipole in constructive terms each of two mutually perpendicular Halbdipol components

2d, wherein the interconnection of the ends of the leading to the respective dipole halves symmetrical or substantially or approximately symmetrical lines such that always the corresponding line halves of the adjacent, mutually perpendicular dipole halves are electrically connected. The electrical supply of each diametrically opposite dipole halves is decoupled for a first polarization and a second polarization orthogonal thereto. The vector dipole radiators thus constructively form a dipole square, but radiate electrically in a + 45 ° polarization Pl or -45 ° polarization P2.

The dipoles or half-dipole components shown in the radiator 2 ultimately form the dipole structure whose radiator elements are generally referred to as the radiator structure 102, which essentially shape and influence the radiation pattern of this radiator type.

As the second type of dipole radiator, a second radiator in the form of a dual-polarized, cup-shaped dipole radiator 3 is used. This second dipole radiator is likewise sufficiently known from the prior art and is described in particular in WO 03/065505 A1, to the disclosure of which reference is made in its entirety and made to the content of this application. In the exemplary embodiment shown, the cup-shaped dipole radiator 3 comprises four surface area elements 3 a, wherein the boundary edges 3 f (see FIG. 2) of the area elements remote from the reflector base 1 a form the dipole radiating elements or the radiation pattern form essential radiator structure 103 in particular by the radiator structure top side. The surface elements 3a are fed electrically to four feed points 3b, wherein the feed to the feed points is at least approximately in-phase and approximately symmetrical. This makes it possible for the dipole radiator 3 - in analogy to the dipole radiators 2 - to radiate in the + 45 ° polarization Pl and the -45 ° polarization P2. As can be deduced from WO 03/065505 A1, however, the feed at the feed points 3b is in each case such that in each case the outer conductor is rotated by one end of a corresponding radiator element 3a and the inner conductor is rotated by 90 ° with the adjacent end of an adjacent one aligned radiating element 3a is electrically connected. Between two such illustrated radiator elements then runs from the above-mentioned prior publication as known to be taken gap or slot 3 g, which extends to a lower base portion adjacent to the reflector plane E.

The individual surface elements 3a of the radiator 3 are trapezoidal in shape and extend substantially obliquely out of the reflector base 1a. The obliquely running out of the reflector bottom edges of the surface elements 3a also have bends 3c, wherein between adjacent folds a gap is formed. This shape and arrangement of the surface elements, the cup-shaped shape of the dipole radiator 3 is achieved. It should be noted that other types of cup-shaped dipole radiators can be used in the antenna according to the invention. In particular, the surface elements 3a need not be formed over the entire surface, but may have a frame structure formed of a plurality of rods. In particular, all dipole radiator molds described in the aforementioned application WO 03/065505 A1 are conceivable for use in the present invention.

The second radiator 3 radiates in a lower frequency band, the center frequency of which is substantially half the center frequency of the first radiator 2, ie can radiate in the 900 MHz band, for example in the range of 800 MHz to e.g. 1,000 MHz.

In the embodiment shown with reference to Figures 1 and 2, in addition to the three radiators 2 shown for the higher frequency band with the associated radiator structure 102, a radiator 3 with the associated radiator structure 103 for the lower frequency band shown. The middle radiator 2 for the higher frequency band is arranged centrally in plan view inside the cup-shaped second radiator 3, this radiator 2 is arranged on a pedestal 4, so that the plane of the lines 2c and especially the semi-dipole components 2d and thus the emitter elements or emitter structure 102 are in the embodiment shown above the upper edge of the cup-shaped radiator 3, which will be explained in more detail below with reference to Figure 2. The pedestal 4 is preferably made of electrically conductive material or is at least provided with a conductive top layer. The pedestal thus has an upper side, which is aligned parallel to the reflector plane or at least substantially parallel to the reflector plane E. The podium top 4f thus forms a plateau 4f, which is also referred to below as an auxiliary reflector 4f. The size of the auxiliary reflector 4f is larger than the base cross section. As can be seen from the drawings, in the embodiment shown, the podium top side is formed substantially rectangular or square, wherein recesses may be provided in the corner regions (as is apparent from the plan view of Figure 1). The longitudinal extent of the podium top side or of the plateau 4f in this case has a longitudinal dimension in the X or vertical direction of the reflector 1, which corresponds to at least λ / 4 and at most λ, wherein the smallest value of λ of the wavelength at the lower band limit (lower frequency) of the upper Frequency band corresponds. The largest value of λ corresponds to that value at the upper band limit (highest frequency) with respect to the upper transmitted frequency band. Correspondingly, the dimensioning in Quererstre- ckung transverse to the X or vertical direction of the reflector and is selected. A preferred value for the lower longitudinal or transverse extent for the diameter of the plateau surface is, for example, λ / 4 at a frequency of 2.7 GHz.

As can also be seen from the drawings, the dimension for the longitudinal extent in the X or Y direction of the top of the podium corresponds approximately to the height of the pedestal above the plane of the reflector. This measure can thus be for example λ / 4, as well as the preferred distance height of the dipole beam elements with respect to the reflector plane or the plane of the pedestal (which is preferably λ / 4). In general, it can be said that the distance of the dipole radiators from the plane of the reflector or the podium top side is generally between λ / lβ and λ and preferably λ / 8 to λ / 2, ie preferably λ / 4 (as is basically the case in FIG DE 198 23 749 Al is known). In this case, λ usually represents a value with respect to the frequency band to be transmitted, preferably the smallest one Value for λ (corresponding to the upper end of the respective frequency band). A preferred range for the distance of the dipole radiator elements to the reflector plane or to the pedestal height is therefore λ / 6 to λ / 4.

As can also be seen from the drawings, 4g of the podium top side 4f or the plateau 4f so-called lobes 4a are provided on the boundary sides or edges 4g, which will be discussed in more detail later. However, it can already be emphasized at this point that the platform top 4f may have different shapes, for example, square, rectangular, ^' generally n-polygonal or curvy, ie, round, etc. may be, the pedestal is in each case dimensioned larger than that Base cross-section of the corresponding radiator.

FIG. 2 shows a sectional view along the line I-I of FIG. 1. The structure of the cup-shaped radiator 3 and of the pedestal 4 arranged therein can be seen in more detail in FIG. It can be seen, in particular, that the individual surface elements 3 a consist of a lower, obliquely upwardly extending section 3 d, at the upper end of which a section 3 e runs perpendicular to the reflector plane E and ends at upper boundary edges 3 f, which form the dipole beam elements of the Make radiator 3. Further, it will be seen that the pedestal 4 has downwardly tapered side walls 4b and is hollow inside. The vector dipole emitter 2 is arranged centrally on the pedestal, and the obliquely upwardly extending tabs 4a also extend from the pedestal. '

By using the pedestal is achieved that the Half-dipole components of a vector dipole radiator 2 arranged on the pedestal lie in a first radiation plane S1, which lies in the vicinity of the radiation plane S2 which is formed by the boundary edges 3f of the spherical radiator 3. In the exemplary embodiment shown, the plane Sl is higher than the plane S2. However, it is also conceivable that the plane Sl is substantially the same height as the plane S2 or is also arranged slightly below the plane S2. In particular, the distance between the plane S is in a range of between 75% and 150% of the distance of the plane S2 of the ^'reflector plane E. This lower limit but may also be at 80%, 90%, 100% or even 110% are. The corresponding upper limit may also be 140%, 130% or 120%. FIG. 2 also shows a third radiation plane S3, in which the dipoles of the left and right vector dipole radiators 2 are located. The plane S3 is much lower than the levels Sl and S2, since the left and right radiators 2 are not on a-podium. It is also conceivable, however, that the left and right radiators 2 are also arranged to: ^• a respective pedestal 4, will be described in more detail below. It can also be seen from FIG. 2 that the top side of the pedestal lies at an at least slightly greater distance from the plane E of the reflector than the plane S3 in which the dipole elements of the dipole radiator mounted on the reflector come to lie for the higher frequency band , In other words, therefore, the distance between the plateau height and the plane E of the reflector is equal to or at least slightly greater than the distance of the dipole radiator of the radiator device 2 with respect to the plateau top or the plane E of the reflector in the case of the radiator 102, directly on the reflector sitting. By using a pedestal, with which a dipole radiator 2, which radiates in an upper frequency band, is spaced from the reflector plane E, the radiation behavior, in particular the half-value width of the radiation in the upper frequency band, can be influenced in an advantageous manner. By appropriate shaping of the pedestal 4, this can also act as a second reflector for the radiator located on the pedestal, whereby the radiation behavior can continue to be positively influenced.

With regard to its radiator elements, radiator element upper side or generally its radiator structure 102, the radiator 2 for the higher frequency band arranged centrally on the pedestal 4 in the radiator 3 for the low frequency band is arranged at such a height with respect to the reflector plane E at least in the area of this radiator which is greater than 0.4 λ, where λ is the average wavelength for the center frequency of the radiator 2 provided for the higher frequency band range. However, this lower limit may also be 0.6 λ, 0.8 λ, 1.0 λ or for example 1.2 λ or more. On the other hand, the distance to the reflector plane E should not be greater than 2 λ, but this upper limit can also be at 1.8 λ, 1.6 λ or 1.4 λ, λ-is again related to the center frequency of the upper frequency band , For example, if the radiators 102 for the higher frequency band in the 1800 MHz range and the radiator 103 in the 900 MHz band range (ratio 2: 1) radiate, the distance of the dipole radiator elements of the radiator 103 for the lower frequency band from the plane E of the reflector should not be greater than λ and not smaller than 0.2 λ, for example, if the levels Sl. and S2 in the same or at least approximately or approximately at the same height. Again, X is a wavelength from the frequency band to be transmitted, preferably the smallest wavelength corresponding to the highest frequency of the lower frequency band.

FIG. 3 again shows a side detail view of the pedestal 4 shown in FIG. 2 with the vector dipole radiator 2 arranged thereon. FIG. 3 shows, in particular, that the pedestal 4 has a closed structure with four side walls 4b, whereby the level of the pedestal top side 4d starting from the already mentioned four lobes 4a in the embodiment shown extend obliquely upwardly and outwardly extending. On the upper pedestal or plateau level then the radiator 2 is mounted with its base.

It can be seen from FIG. 3, especially in conjunction with FIGS. 1 and 2, that the platform has an approximately square structure, the lateral boundaries of which lie parallel to the semi-dipole components of the vector dipole 2. The of the platform from these ^'side intervals upwardly rising side walls (lobes) 4b do not extend therefore also not placed perpendicular to the plane of the platform and perpendicular to the reflector plane E, but are at an angle to the outside .verlaufend in the illustrated embodiment. This

Angle is preferably more than 10 ° and preferably less than 40 °. In particular, this angle is a by 20 ° (Figure 2) with respect to the vertical. Incidentally, the side walls 4a are not circumferentially closed, but open in the corner areas, as is apparent in particular from the plan view of Figure 1. However, this angle α can also assume any other values, so that the lobes or the lobe-shaped extensions 4a can even lie in the plane of the podium top side or the plateau 4f formed thereby and can thus be interpreted in the manner of an auxiliary reflector extension. In addition, these lobes 4a may be angled downwards even with respect to the top of the podium 4f, for example, almost up to a vertical angle. In other words, the angle between the lobes 4a and a plane parallel to the reflector plane E between ± 85 ° or _. + 80 ° and 0 ° vary, in which the lobes are aligned parallel to the reflector plane.

The longitudinal extent of the lobes starting from the pedestal 4 towards its free end is preferably λ / 10 to λ, the smallest value of λ corresponding to the wavelength at the upper band limit (highest frequency) of the upper transmitted frequency band and the maximum value of λ to the wavelength , at the lower band limit (lowest frequency) corresponds to the upper frequency band to be transmitted. The same dimensioning also applies to the transverse extent of the lobes, these values representing preferred values.

The flaps are preferably symmetrically formed and aligned on each pedestal. However, certain imbalances can sometimes be beneficial in terms of their angular orientation as compared to another lobe on a pedestal or its sizing. Finally, however, the tabs can be omitted altogether or ^• "a peripheral boundary .or sidewall 4b closed.

FIG. 4 shows a plan view of a second embodiment. shape of the antenna according to the invention. In the embodiment of FIG. 4, the same radiators 2 and 3 as in FIG. 1 are used, and the radiators are also arranged in a plan view just as in the embodiment of FIG. In contrast to the embodiment of FIG. 1, however, the left and right first radiators are also arranged on a pedestal, wherein this pedestal has a closed, substantially rectangular pedestal surface 4c with a corresponding boundary 4d framing and circumscribing the pedestal surface. The pedestal, on which the central emitter 2 is arranged, further corresponds to the pedestal, which is also used in the embodiment of FIG.

Figure 5 shows a sectional view taken along the line II-II of Figure 4. It can be seen in particular that the left and right platforms are identical and have a different shape than the middle pedestal. The left and right platforms form-essentially a tower with obliquely upwardly extending side walls, wherein at the top of the tower, the platform platform is formed with the circumferential closed side wall boundary 4c. In addition, the left and right receptacles have raised pedestals 4, on each of which a first radiator 2 is positioned. The left and right pedestals have - analogous to the middle pedestal - in the lower part of a cavity which is bounded by tapered side walls 4b. In contrast to the embodiment of FIG. 1, in the embodiment of FIG. 5 there are only two radiation planes S1 and S2, wherein all three first radiators 2 are arranged in the first radiation plane S1. The arrangement can also be chosen differently from FIG. 5 such that the pedestal height of the outer radiator elements or radiator structures 102 is, for example, slightly lower. ■ ger or higher than the radiator elements or radiator structure 102 of the radiator 2, which is arranged centrally in the radiator 3rd, so that the radiator plane S3 for the not arranged within the radiator for the low frequency band emitter 2 deviates from the radiator plane Sl.

FIG. 6 shows the same side view as FIG. 5, but the side view of FIG. 6 is not cut. It can be seen here in particular that the left and right pedestals have inclined, closed side walls, so that they have a laterally, i. in conversion

^■ closed towards the tower, open towards the top. • ■■, on whose plateau or platform surface 4d the corresponding radiator is arranged.

Figure 1 shows a plan view of a third embodiment of the present invention ^'s antenna. The antenna of Figure 7 differs from the antenna of Figure 1 in that a different type of second radiator is used. Otherwise, the embodiment of Figure 7 corresponds to the embodiment ^" of Figure 1, so that a detailed description is omitted.

In FIG. 7, instead of a spherical radiator 3, a dipole square 3 'is used which comprises four rod-shaped dipoles consisting of two dipole halves 3a' each. The individual dipoles extend in this case at a 45 "angle to the side walls Ib of the reflector 1. In this way, the dipole square radiates - in the +45 ° polarization Pl and the -45 ° - analogously to the cup-shaped radiator of FIG The structure of emitters in the form of dipole squares has long been known from the prior art.For example, reference is made to the document DE 198 23 749 A1, which by this reference with its entire disclosure content is made part of this application.

FIG. 8 shows a side view of FIG. 7 cut along the line III-III. It can be seen that-analogously-as in FIG. 2-there are three different radiation planes S1, S2 and S3. In the lowermost radiating plane S3, the left and right first radiators 2 are arranged. In the radiation plane S2, which is higher than the radiation plane S3, are the dipoles of the dipole radiator 3. In the uppermost radiation plane Sl are the dipoles of the radiator 2, which is arranged on the pedestal 4. It can be seen in FIG. 8 that the distance between the radiation planes S1 and S2 is significantly greater than in the embodiment according to FIG. 2. It should be noted here that it is also possible in the embodiment of FIG Right first emitters are also positioned on a pedestal, so that they are also in the radiation plane Sl. Here, the same pedestal can be used, which is used in Figure 5 for the left and right first radiator, but the height of the pedestal is to be adapted to the height of the plane Sl in Figure 8.

FIG. 9 shows an unsectioned side view similar to FIG. 8. It can be seen in this figure that the middle pedestal 4 is identical to the pedestal shown in FIG. But even here, the pedestals for the outer radiator 102 may be slightly formed in height so that the radiator height S3 at the radiator height Sl relative to the reflector plane E at least slightly different from each other.

Notwithstanding the embodiments shown can also the radiator 2 for the higher frequency band not as

Vector dipoles, but for example as dipole squares

(similar to the radiator type in the embodiment according to

FIGS. 7 to 9) or in the form of dipole crosses. Restrictions on the use of certain

There are therefore no dipole radiators or dipole radiators.

The explained radiation planes S1, S2 and S3 are in principle aligned parallel to the reflector plane E. In individual cases, however, the radiator elements or radiator structures 102, 103 could possibly also deviate and be inclined at an angle of less than ± 5 ° with respect to this plane. Therefore, if necessary, could also. At least in a partial length of the reflector, the radiator planes Sl, S2 and S3 deviate in such an angle of less than ± 5 ° relative to the reflector plane.

It is always referred to that the explained distances between the radiation planes and thus the distances between the ^" radiator elements and the radiator structure 102, 103 have the distances explained at least in the area of the radiators 2, 3, 3 'in question It is also possible to use an antenna arrangement which comprises a plurality of reflector sections which, for example, have reflector sections which are folded over one another in an angular range in the circumferential direction in order to radiate the elements of the control elements seated thereon at different azimuth angles.

It can thus be stated on the basis of the exemplary embodiments shown that the antenna according to the invention, in particular the mobile radio antenna according to the invention, can be described by the following features, namely: there are several dipole radiators 2; 3, 3 ', namely at least one first dipole radiator 2 and at least one second dipole radiator .3, 3', which are arranged in front of a reflector 1, - the at least one first and the at least one second dipole radiator 2; 3, 3 'have associated first or associated second radiator structures 102, 103, which optionally comprise radiator elements, which radiates at least one first dipole radiator 2 in a lower frequency band and the at least one second dipole radiator 3, 3' radiates in a comparatively higher frequency band,

-, At least a first radiator structure 102 and an upper side of the at least one first radiator structure 102 of the dipole radiator 2 for the higher frequency band has a distance from the reflector plane E, at least 75% and at most 150% of the distance between the at least one second radiator structure or the upper side of the at least one second radiator structure 103 of the at least one second dipole radiator 3, 3 'for the lower frequency band and the reflector plane E, in particular the at least one first dipole radiator 2 is positioned on a pedestal 4 whose pedestal Top 4d is provided at a distance in front of the reflector plane E, and - in particular, the at least partially electrically conductive pedestal 4 on a pedestal top side 4d, whose area is greater than a base cross section of the first positioned thereon Dipolstrahlers. 2

Furthermore, it proves to be favorable if the distance between the at least one first radiator structure 102 of the at least one first dipole radiator 2 for the higher frequency band has a distance from the reflector plane E, which is greater than 0, 4 λ and preferably less than 2 λ relative to the center frequency of the at least one first dipole radiator 2 for the higher frequency band.

Claims

Patent claims: 1. Antenna, in particular a mobile radio antenna, for operation in at least two frequency bands, with the following features: several dipole radiators (2; 3, 3 ') are provided, which are arranged in front of a reflector (1), the several dipole radiators (2; 3 , 3 ') have radiator elements or radiator structures (102, 103), of the several dipole radiators (2; 3, 3'), at least one dipole radiator (3, 3') is provided, which radiates in a lower frequency band and there is at least one Radiator (2 ^* ) is provided, which radiates in a higher frequency band, characterized by the following further features: the distance of the radiator structure, the radiator elements or the radiator element top (102) of at least one dipole radiator (2) for the higher frequency band is at a distance from the reflector plane (E) which corresponds to at least 75% and at most 150% of the distance between a radiator structure, a radiator element or a radiator element top (103) of at least one dipole radiator (3, 3 ') for the lower frequency band and the reflector plane (E), and / or the distance of the radiator structure, the radiator elements or the radiator element top (102) at least a dipole radiator (2) for the higher frequency band has a distance from the reflector plane (E) that is greater than 0.4 λ and preferably less than 2 λ based on the center frequency of the radiator for the higher frequency. 2. Antenna according to claim 1, characterized by the following features: - the radiator elements or the radiator structure (102) of at least one radiator (2) for the higher frequency range lies in a radiation plane (Sl), and the radiator elements or the radiator structure (103) of at least one dipole radiator (3, 3 ') lie for a lower frequency range in a second radiation plane (S2), the first radiation plane (Sl) being at a greater distance from the reflector plane (E) than the second radiation plane (S2). 3. Antenna according to claim 1, characterized by the following features: the radiator elements or the radiator structure (102) of at least one radiator (2) for the higher frequency range lies in a radiation plane (Sl), and - the radiator elements or the radiator structure (103) at least a dipole radiator (3, 3') for a lower frequency range lies in a second radiation plane (S2), the first radiation plane (Sl) and the second radiation plane (S2) being essentially the same distance from the reflector plane (E). 4. Antenna according to one of the preceding claims, characterized in that one or more first radiators (2), which lie in the first radiation plane (Sl), are each arranged on a pedestal (4) with a larger area than the base cross section of the associated dipole radiator (2), which is connected to the reflector (1) and preferably at least partially electrically is leading. 5. Antenna according to claim 4, characterized in that the pedestal (4) has on its top an electrically conductive and preferably metallic pedestal top (4d), on which a first radiator (2) is positioned. 6. Antenna according to claim 5, characterized in that at least part of the top of the pedestal (4d) comprises a plurality of tabs (4a) which run perpendicularly or obliquely to the reflector plane and which are arranged offset from one another in the circumferential direction in a top view. 1. Antenna according to claim 5 or 6, characterized in that the tabs (4a) are designed at any angle between -90° and +90°, in particular less than ±80°, relative to a plane parallel to the reflector plane (E). are directed. 8. Antenna according to one of claims 5 to 7, characterized in that the tabs (4a) provided in the circumferential direction on the platform (4) or on the top of the platform (4d) are spaced apart from one another or are connected to one another to form a circumferential boundary wall. 9. Antenna according to one of claims 4 to 8, characterized in that in a top view of the reflector (1) the first radiator (2) arranged on the pedestal (4) lies within the border of the pedestal (4). 10. Antenna according to one of claims 4 to 9, characterized in that one or more first radiators (2), which are arranged in the first radiation plane (Sl), are formed in one piece with the associated pedestal (4). • 11. Antenna according to one of the preceding claims, characterized in that in plan view of the reflector (1) one or more first radiators (2) are each arranged essentially in the center of the second radiator (3 ⁾ in a plan view. 12. Antenna according to one of the preceding claims, characterized in that in plan view of the reflector (1) one or more first radiators (2) are each arranged essentially centrally between adjacent second radiators (3). 13. Antenna according to one of the preceding claims, characterized in that further dipole radiators (2) are positioned on the reflector (1). Radiator structure (102) or the top of the associated radiator structure (102), which come to lie in at least a third radiation plane (S3). 14. Antenna according to one of the preceding claims, characterized in that one or more second radiators are dual-polarized dipole squares (3 ') formed from four dipoles. ^{•. • • • ■} 15. Antenna according to one of the preceding claims, characterized in that one or more second radiators are dual-polarized, cup-shaped radiators (3) which have ^radiation edges (3f) or rod-shaped elements at the end remote from the reflector. 16. Antenna according to claim 15, characterized in that the cup-shaped radiators (3) comprise a plurality of full-surface surface elements (3a) which run obliquely or perpendicular to the reflector plane (E) and whose boundary edge is located away from the reflector plane (E-). Radiation edge (3f). 17. Antenna according to one of claims 14 to 16, characterized in that a first radiator (2) is arranged in a top view of the reflector (1) in one or more of the dipole squares (3 ') and / or the cup-shaped radiators (3). is. 18. Antenna according to one of the preceding claims, characterized in that one or more first radiators (2) are dual-polarized cross dipoles and / or vector dipoles. 19. Antenna according to one of the preceding claims, characterized in that the reflector (1) has side walls (Ib) which run in the longitudinal direction of the reflector (1) and extend obliquely and / or vertically from the reflector plane (E), with between the side walls (Ib) _. the plurality of radiators (2, 3, 3 ') is arranged. 20. Antenna according to one of the preceding claims, characterized in that the first dipole radiators (2) are dimensioned so that they are in a lower frequency band in a range from 800 MHz to 1,000 MHz and the second dipole radiators (3, 3 ') so are dimensioned so that they radiate in a frequency band of 1,700 MHz to 2,700 MHz. 21. Antenna according to one of the preceding claims, characterized in that a plurality of first and second radiators (2, 3, 3 ') are arranged next to one another in the longitudinal and / or transverse direction of the reflector (1), with above each second radiator ( 3) a first radiator (2) is arranged essentially centrally and a first radiator (2) is arranged essentially centrally between each pair ^of adjacent second radiators (3). 22. Antenna according to one of the preceding claims, characterized in that all first radiators (2) are arranged in the first radiation plane (Sl) and all second radiators (3, 3 ') in the second radiation plane (S2). 23. Antenna according to one of the preceding claims, characterized in that the frequency bands of the antenna ^' are in the GSM, CDMA and/or UMTS mobile radio frequency range. 24. Antenna according to one of the preceding claims, characterized in that the first radiation plane (Sl) and the second radiation plane (S2) are essentially parallel to the reflector plane (E) or at most at an angle of ±30 ° and preferably up to a maximum of ± is inclined at 5° relative to the reflector plane (E). 25. Antenna according to one of claims 4 to 24, characterized in that the top of the pedestal ( 4d) is rectangular, square, n-polygonal or curved, in particular circular in plan view. 26. Antenna according to one of claims 4 to 25, characterized in that the pedestal surface or the pedestal plateau (4d) has a longitudinal dimension in plan view parallel to the X or vertical direction of the reflector and / or a transverse extension thereto which is at least λ / 4 and a maximum of λ, where the minimum value of λ of the wavelength is at the lower band limit (lower frequency) of the upper transmitted frequency band and the maximum value of λ is at the upper band limit (maximum frequency) of the upper transmitted frequency band. 27. Antenna according to one of claims 4 to 26, characterized in that the tabs (4a) have a longitudinal and / or transverse extension between their side on which they are connected to the platform (4) towards their.m thereof distant free end, which lies between λ/10 and λ, where the smallest value of λ corresponds to the wavelength at the upper band limit (highest frequency) of the upper transmitted frequency band and the maximum value of X corresponds to the wavelength at the lower band limit (lowest Frequency) of the upper frequency band to be transmitted corresponds. 28. Antenna according to one of claims 1 to 27, characterized in that the top of the pedestal (4f) in one Distance in front of the plane (E) of the reflector - which is greater than λ/16 and preferably greater than λ/8 and less than λ and preferably less than λ/2, where λ is a white length of the higher frequency band, preferably the smallest wavelength of the higher frequency band to be transmitted. 29. Antenna according to one of claims 1 to 28, characterized in that the top of the pedestal (4f) has a distance from the plane (E) of the reflector which is equal to or greater than the distance between the radiation plane (Sl) of the radiator elements (102 ) and the top of the pedestal (4f) and/or the distance between the radiation plane (S3) and the plane (E) of the reflector.