WO2025190476A1

WO2025190476A1 - Antenna, mobile communication base station and user device

Info

Publication number: WO2025190476A1
Application number: PCT/EP2024/056537
Authority: WO
Inventors: Jari Van Wonterghem; Casimir EHRENBORG; Michael Freiberger
Original assignee: Telefonaktiebolaget LM Ericsson AB
Current assignee: Telefonaktiebolaget LM Ericsson AB
Priority date: 2024-03-12
Filing date: 2024-03-12
Publication date: 2025-09-18
Anticipated expiration: 2026-09-12

Abstract

An antenna (14) comprises a first array (24) of first dual polarized radiators (16) for a first frequency band and at least one beam shaping element (26). The beam shaping element (26) has a conductor (28) with a first portion (32) extending in a radiation direction (R) as well as a second portion (34) electrically connected to the first portion (32) and extending in a direction different from the radiation direction (R). The conductor (28) of the beam shaping element (26) is ungrounded and has an electrical length between 1/3 and 3/4 of a wavelength of an average frequency of the first frequency band. Further, a mobile communication base station (10) and a user device (12) are shown.

Description

Antenna, mobile communication base station and user device

Technical Field

The invention relates to an antenna, a mobile communication base station and a user device.

Background

Base station antennas that are known in the art usually cover a sector of 120°. It is therefore common for such antennas to be designed to have a half power beam width of 60°.

At the same time, the antennas are designed as multi-band antennas having a first array of first dual polarized radiators designed for a first frequency band which are interleaved with a second and possibly a third array of radiators designed for different frequency bands.

These further radiators but also additional radiators for the first frequency band deform the antenna horizontal pattern so that the half power beam width (HPBW) is not constant across the desired frequency band. Additionally, the isolation between the antenna arrays and the polarizations as well as the crosspolar level is influenced. In order to mitigate these effects, it is known to connect neighboring radiator columns to each other's feeding networks through hybrid couplers or cross wiring. Further, decoupling elements such as grounded monopoles have also been used to shape the beams.

Such antennas are known, for example, from US 10587046 B2, CN 114883802 A and WO 2023/065981 Al.

However, these solutions to shape the beam are very expensive and inflexible.

Summary

It is thus an object to provide an antenna, a mobile communication base station and a user device having a more constant half power beam width across the frequency of the desired frequency band.

For this purpose, an antenna, in particular for a mobile communication base station, is provided. The antenna comprises a first array of first dual polarized radiators designed for a first frequency band and at least one beam shaping element. The at least one beam shaping element comprises a conductor with a first portion extending in a radiation direction of the first array as well as a second portion electrically connected to the first portion at a connection point of the beam shaping element and extending in a direction different from the radiation direction. The conductor of the at least one beam shaping element is ungrounded and has an electrical length between 1/3 and 3/4 of a wavelength of an average frequency of the first frequency band.

By providing a beam shaping element having a first portion and a second portion extending in different directions and, at the same time, having an electrical length between 1/3 and 3/4 of the wavelength of the average frequency of the first frequency band, and the beam shaping element may be ungrounded and thus may be placed flexibly within the antenna. At the same time, it may be manufactured easily and mounted at low costs.

The inventors have realized, that monopole radiation characteristics of the first portion are maintained if the second portion extends in a different direction. Further, an electrical length between 1/3 and 3/4 of the wavelength of the average frequency of the first frequency band allows the current induced by electromagnetic radiation in the first frequency band to resonate inside the beam shaping element even though the beam shaping element itself is not grounded.

In particular, the electrical length of the conductor is 1/2 of the wavelength of the average frequency of the first frequency band, yielding to a further improved monopole radiation characteristics of the beam shaping element.

Within this disclosure, "ungrounded" means in particular not capacitively grounded or galvanically grounded. For example, the beam shaping elements do not have a capacitive or galvanic connection to the reflector, i.e. its ground plane.

For example, the beam shaping elements are galvanically separate from the radiators.

The first and second portion are for example galvanically connected, in particular directly attached or merging into one another.

For example, the conductor consists of the first portion and the second portion.

In an embodiment, the first portion has an electrical length between 1/8 and 3/8 of the wavelength of the average frequency of the first frequency band, in particular of 1/4 of the wavelength of the average frequency of the first frequency band. This way, excellent monopole radiation characteristics of the first portion are ensured.

For example, the electrical length of the first portion is determined from the free end to the connection point.

In an aspect, the second portion extends in a direction perpendicular to the radiation direction, in particular in the same direction as a column of the first array, leading to further improved monopole radiation characteristics of the first portion.

For simplifying manufacture further, the conductor of the beam shaping element may extend in a single plane, in particular in a plane extending in the radiation direction and in a direction of a column of the first array.

In an embodiment, the first portion has a free end and a connected end, and the second portion has a free end and a connected end, wherein the connected ends of the first portion and the second portion are electrically, in particular galvanically connected forming the connection point. This way, a simple and small beam shaping element is provided.

For example, the beam shaping element has an L-shape.

In another embodiment, the first portion has a free end and a connected end, and the second portion has at least two free ends, the connected end of the first portion being electrically, in particular galvanically connected to the second portion at the connection point, wherein the connection point is spaced apart from the free ends of the second portion. The parts of the second portion opposite to one another with respect to the connection point cancel each other's influence on electromagnetic radiation in the first frequency band in the plane perpendicular to the radiation direction R. This leads to improved radiation characteristics of the antenna.

The beam shaping element may have a T-shape. It is also conceivable that the beam shaping element has three, four or more free ends.

In order to improve the radiation characteristic further, the connection point may be located at the mid-point between the free ends of the second portion, and wherein the second portion may be symmetric with respect to the connection point. In an aspect, the electrical length of the conductor is the electrical length between two free ends of the beam shaping element, in particular between the free end of the first portion and one free end of the second portion. This way, monopole radiation characteristics are further improved.

In an embodiment, the first portion and/or the second portion comprise at least one end section extending from the free end towards the connection point and a center section, in particular extending from the connection point towards the respective free end, wherein the conductor is larger in width and/or diameter in the end section than in the center section. The end sections increase the capacitive loading at the end of the first and second portion, which leads to an increased ability of the beam shaping element to shape the beam.

For example, the change of width and/or diameter occurs abruptly or forming a taper. In particular, all of the free ends are provided with an end section.

In an aspect, the physical length of the end section is between 1/2 and 1/4 of the length of the physical distance between the connection point and the respective free end, leading to further improved beam shaping abilities.

For providing simple beam shaping elements at low costs, the beam shaping element may be a metal sheet forming the conductor or may comprise a carrier supporting the conductor, in particular a PCB or a thermoplastic part supporting the conductor.

In an embodiment, the first portion and/or the second portion comprise at least one transparency section, in particular wherein the conductor extends in meanders at least in a first part of the transparency section and/or is larger in width than the center section at least in a second part of the transparency section. The transparency section reduces scattering and coupling effects of electromagnetic radiation in a frequency band of the at least one further array of radiators. Thus, the radiation characteristics of the antenna in the further frequency band are not deteriorated by the beam shaping elements.

In an aspect, the beam shaping element comprises at least one conductive plate being separate from the conductor and corresponding to the second part of the transparency section, wherein the at least one conductive plate and the corresponding second part form a capacitor, in particular wherein the conductive plate and the second part are located opposite to one another on different surfaces or layers of the carrier. This way, a filter function is achieved by the capacitor, in particular in conjunction with the meanders of the first part.

The conductor may be a metallization on the carrier, e.g. on the PCB or thermoplastic.

In an embodiment, the beam shaping element is arranged between two of the first radiators of the first array, in particular wherein the first array comprises at least two columns with at least two first radiators each, wherein between corresponding first radiators of adjacent columns, one of the at least one beam shaping elements is arranged. In this arrangement, variations in the half power beam width over frequency are further reduced.

In order to provide a multi-band antenna, the antenna may comprise at least one further array of radiators designed for a frequency band different from the first frequency band.

For above mentioned purpose a mobile communication base station is further provided. The base station has at least one antenna as described above.

Further, for above mentioned purpose, a user device for mobile communication is provided. The user device has at least one antenna as described above.

The features and advantages described with respect to the antenna also apply to the base station and/or the user device and vice versa. Brief Description of the Drawings

Further features and advantages will be apparent from the following description as well as the accompanying drawings, to which reference is made. In the drawings:

Figure 1 shows a mobile communication base station according to an embodiment of the invention with an antenna according to an embodiment of the invention, and a user device according to an embodiment of the invention with an antenna according to an embodiment of the invention,

Figure 2 shows a simplified perspective view of the antenna of the mobile communication base station of Figure 1,

Figure 3 shows a schematic side view of a beam shaping element of the antenna of Figure 1,

Figure 4 shows a diagram of the half power beam width HPBW over frequency F for an antenna known in the art and for an antenna according to an embodiment of the invention,

Figure 5 shows a schematic side view of a beam shaping element of an antenna according to a second embodiment of the invention,

Figure 6 shows a schematic side view of a beam shaping element of an antenna according to a third embodiment of the invention,

Figure 7 shows a schematic side view of a beam shaping element of an antenna according to a fourth embodiment of the invention, and

Figure 8 shows a simplified perspective view of an antenna according to a fifth embodiment of the invention.

Detailed Description

Figure 1 shows an embodiment of a mobile communication base station 10 and an embodiment of a user device 12. The mobile communication base station 10 has a plurality of antennas 14 for providing speech and data connections to user devices. Mobile communication base stations 10 are also referred to as mobile communication cell sites.

The mobile communication base station 10 may be an access network node of a radio access network of a telecommunication network, or any other similar 3rd Generation Partnership Project (3GPP) access nodes or non-3GPP access points.

Moreover, as will be appreciated by those of skilled in the art, an access a network node is not necessarily limited to an implementation in which a radio portion and a baseband portion are supplied and integrated by a single vendor. Thus, it will be understood that network nodes include disaggregated implementations or portions thereof.

For example, in some embodiments, the mobile communication base station 10 is an Open-RAN (ORAN) network node. An ORAN network node is a node in the telecommunication network that supports an ORAN specification (e.g., a specification published by the O-RAN Alliance, or any similar organization) and may operate alone or together with other nodes to implement one or more functionalities of any node in the telecommunication network, including one or more network nodes and/or core network nodes.

Examples of an ORAN network node include an open radio unit (O-RU), an open distributed unit (O-DU), and an open central unit (O-CU).

The antenna 14 of the mobile communication base station 10 is a multiband antenna to provide speech and data connections in various frequency bands.

The user device 12 has an antenna 14 and may be a mobile phone, a laptop computer, a customer premises equipment (CPE) or the like. The antenna 14 of the user device 12 is also a multiband antenna allowing a speech and/or data connection to the mobile communication base station 10 and/or to a communication satellite.

Figure 2 shows exemplarily an antenna 14 of the mobile communication base station 10 in a simplified perspective view. Even though the antenna 14 of the mobile communication base station 10 is discussed in the following, the same applies for the antenna 14 of the user device 12.

The antenna 14 has a plurality of first dual polarized electromagnetic radiators 16, a plurality of second dual polarized electromagnetic radiators 18 (only two second radiators 18 are shown for simplification), and a common reflector 22. Further, the antenna may also have a plurality of third dual polarized electromagnetic radiators (not shown for simplification) or more than three kinds of radiators.

The second radiators are located in a plane which has a smaller distance to the common reflector 22 as the plane in which the radiator heads of the first radiators 16 are arranged. The same holds true for the third dual polarized electromagnetic radiators.

The terms "first", "second" and "third" are used within this disclosure only for differentiation purposes and do not imply any order or quality of the items.

The first radiators 16 form a first array 24 designed for a first frequency band. Thus, the first radiators 16 are designed to transmit and receive electromagnetic waves in the first frequency band.

Likewise, the second radiators 18 form a second array for a second frequency band. Thus, the second radiators 18 are designed to transmit and receive electromagnetic waves in a second frequency band.

Similarly, the third radiators form a third array for a third frequency band, and so forth. The first frequency band lies below the second frequency band, in particular fully, i.e. not overlapping with the second frequency band.

The third frequency band lies above the second frequency band, in particular fully, i.e. not overlapping with the second frequency band.

For example, the first frequency band lies below 1.0 GHz, in particular the first frequency band lies between 600 MHz and 960 MHz.

For example, the second frequency band lies above 1.0 GHz, in particular the second frequency band is 1.4 GHz to 2.7 GHz.

It is also conceivable that the first frequency band lies between 1685 MHz to 2690 MHz. In this case, the second frequency band may lie below the first frequency band or further above the first frequency band, e.g. between 3.4 GHz and 3.8 GHz.

The first radiators 16 and the second radiators 18 are interleaved with one another with respect to an orthogonal projection onto the common reflector 22. Further, the third radiators and further radiators may also be interleaved with the first radiators 16 and the second radiators 18.

In the shown example, the first array 24 has multiple columns of first radiators 16, for example two columns of five first radiators 16 each.

The columns extend in a direction of the antenna 14 referred to as the direction C of the column within this disclosure. The direction C of the column is, for example, parallel to the reflector 22.

Further, the antenna 14 has a radiation direction R. The radiator direction R is, for example, perpendicular to the reflector 22.

The direction perpendicular to the radiation direction R and the direction C of the column is referred to as the transverse direction T. Directional terms like "up", "down", "above", "vertical", etc. are to be understood with respect to the radiation direction R of the radiator (also referred to as "vertical"). "Sideways" or "horizontal" is to be understood as a direction perpendicular to the radiation direction R.

The reflector 22 is located below the first radiators 16 and the second radiators 18. The reflector 22 is in particular of metal, or a metallized carrier, for example a metallized PCB. It is also conceivable, that the reflector 22 comprises a Frequency Selective Surface (FSS) or a metamaterial.

The reflector 22 is grounded and thus provides a ground plane.

The first radiators 16 and, for example, also the second radiators 18 are mounted to the reflector 22 so that the radiator heads of the radiators 16, 18 are located above the reflector 22.

Further, the antenna 14 comprises multiple beam shaping elements 26.

The beam shaping elements 26 are arranged in three rows in the shown example.

The rows extend in the direction C of the columns, in which the beam shaping elements 26 are arranged one behind the other.

Two of the rows are arranged on the lateral edges of the antenna 14, for example the lateral edge of the common reflector 22.

The third row of the beam shaping elements 26 is arranged between the two columns of the array 24 of the first radiators 16.

Each beam shaping element 26 of the third row is located between two first radiators 16 in the transverse direction T, namely between corresponding first radiators 16 of the first and second column. For example, between the first radiator 16 of the first column and the first radiator 16 of the second column the first beam shaping element 26 of the third row is located.

The beam shaping elements 26 of the first and second row may be arranged accordingly. Thus, seen in the transverse direction T, the first radiators 16 and the beam shaping elements 26 are arranged altematingly.

It is also conceivable, that the antenna comprises more than two columns of first radiators 16 and more than three rows of beam shaping elements 26. In particular, between corresponding first radiators 16 of adjacent columns, a beam shaping element 26 is provided.

An exemplary beam shaping element 26 is shown in Figure 3 in an enlarged side view. For example, all beam shaping elements 26 are identical to one another.

The beam shaping element 26 comprises a conductor 28. The conductor 28 extends in a single plane, which is, in the shown embodiment, the plane spanned by the radiation direction R and the direction C of the columns.

The beam shaping element 26 may be made of a metal sheet which forms the conductor 28.

Alternatively, the beam shaping element 26 may comprise also a carrier 30 (shown in dashed lines in Figure 3) supporting the conductor 28.

In this case, the conductor 28 may be a metallization applied to the carrier 30, which may be a PCB or a thermoplastic part.

The beam shaping element 26 may be mounted to the reflector 22, wherein however, the conductor 28 is not grounded, neither capacitively nor galvanically. The beam shaping elements 26, more precisely the conductors 28, are galvanically separate from the first radiators 16 or any other radiator of the antenna 14.

As can be seen in Figure 3, the conductor 28 comprises a first portion 32 and a second portion 34.

The first portion 32 extends in the radiation direction R and it is electrically connected, in particular galvanically connected, to the second portion 34 at a connection point 36. The first portion 32 is, for example, attached to the second portion 34.

The first portion 32 has a free end 38 and a connected end 40.

The first portion 32 extends from the connection point 36 with its connected end 40, and the free end 38 is the end facing away from the connection point 36 and thus the second portion 34.

The connected end 40 is attached to the second portion 34 at the connection point 36.

The second portion 34 extends in a direction different from the radiation direction R. In the shown embodiment, the second portion 34 extends in the direction C of the columns.

It is, however, also conceivable that the second portion 34 extends in the transverse direction T or even in the transverse direction T and the direction C of the columns. In the latter case, the second portion 34 may have a T- or starshape as seen in a top view.

In the example of Figure 3, the second portion 34 has two free ends 38. The connection point 36 is located between the free ends 38 of the second portion 34, i.e. spaced apart from the free ends 38. In the shown embodiment, the connection point 36 is located in the mid-point between the free ends 38 of the second portion 34, i.e. halfway between the free ends 38 of the second portion 34.

In the example of Figure 3, the second portion 34 is symmetric with respect to the connection point 36. In particular, the entire beam shaping element 26 is symmetric with respect to an axis in the radiation direction R through the connection point 36.

The beam shaping element 26 has a T-shape seen in the traverse direction T.

It is conceivable, that the second portion 34 has three, four or more free ends 38.

The first portion 32 and the second portion 34 each have a center section 42, which extend from the connection point 36 outwards and towards the respective free end 38.

In the first embodiment, the beam shaping element 26 comprises at each of the free ends 38 of the first portion 32 and second portion 34 one end section 44 extending towards the connection point 36.

In the center section 42, the conductor 28 is straight and has a first width.

In the end section 44, the conductor 28 extends straight but has a second width which is larger than the first width of the center section 42. Thus, the conductor 28 is wider in the end sections 44 than in the center sections 42.

In cases in which the conductor 28 is not flat, the conductor 28 has a larger diameter in the end section 44 than in the center section 42.

For example, as seen in Figure 3 the width (diameter) of the conductor 28 changes abruptly at the transition from the center section 42 to the end section 44. Alternatively, the conductor 28 may have a taper at the transition from the center section 42 to the end section 44.

The physical length of the end section 44 is between 1/2 and 1/4 of the length of the physical distance between the connection point 36 and the respective free end 38.

The physical length of the first portion 32, the second portion 34, the center section 42 and the end section 44 as well as the sizes of the first width and the second width are chosen to achieve the following electrical length of the beam shaping element 26.

The electrical length of the conductor 28, which may be regarded as the electrical length (via the connection point 36) between the free end 38 of the first portion 32 and one of the free ends 38 of the second portion 34, is between 1/3 and 3/4, in particular 1/2 of a wavelength of an average frequency of the first frequency band.

The first portion 32 has an electrical length, i.e. an electrical length between the free end 38 and the connected end 40 of the first portion 32 of at least 1/8 and at most 3/8 of the wavelength of the average frequency of the first frequency band. For example, the electrical length of the first portion 32 is 1/4 of the wavelength of the average frequency of the first frequency band.

The beam shaping element 26 behaves, for electromagnetic radiation in the first frequency band, as a grounded monopole of an electrical length of one quarter of the wavelength of the average frequency of the first frequency band. This behavior is achieved by the second portion 34 which increases the electrical length of the conductor 28 to about 1/2, in particular exactly 1/2 of the wavelength of the average frequency of the first frequency band. This way the current induced by the electromagnetic radiation can resonate inside the beam shaping element 26 without needing to be grounded to form an image current. Further, as the second portion 34 extends in a direction different from the direction of the first portion 32, the beam shaping element 26 has monopole radiation characteristics, at the same time.

By virtue of the beam shaping elements 26, the half power beam width across frequency can be held more constant across the first frequency band, as illustrated in Figure 4. Figure 4 shows the half power beam width (HPBW) over the frequency (F) of the electromagnetic radiation. The dashed lines illustrate the half power beam width of an antenna as known in the art and the solid line shows the beam width of an antenna 14 according to the invention.

As can be seen, the half power beam width of an antenna 14 according to the invention is very stable at about 79 degrees for the vast majority of the first frequency band.

Thus, the beam shaping elements 26 allow to adjust the beam width of the antenna 14 in a very cost-efficient and flexible way, as the beam shaping elements 26 can be manufactured easily and be positioned freely within the antenna 14.

The end sections 44 lead to a capacitive loading which increase the effect of the beam shaping elements 26 further.

Figures 5 to 8 show further embodiments of an antenna 14 according to the invention, which correspond substantially to the first embodiment. Thus, in the following, only the differences are discussed and the same and functionally in the same elements are labeled with the same reference signs.

Figure 5 shows a beam shaping element 26 according to a second embodiment of the antenna 14.

The beam shaping element 26 corresponds to the beam shaping element 26 of the first embodiment. In difference to the first embodiment, the second portion 34 comprises several transparency sections 46. The first portion 32 is, for example, free of transparency sections 46.

In the shown embodiment, the second portion 34 comprises four transparency sections 46, two of which being arranged between the connection point 36 and one of the free ends 38 and the other two being arranged between the connection point 36 and the other free end 38.

Each of the transparency sections 46 has a first part 48 and a second part 50. In the first part 48, the conductor 28 extends in meanders. In the shown embodiment four meanders are realized in the first part 48.

The width of the conductor 28 in the first part 48 is smaller than the second width and corresponds in particular to the first width.

In the second part 50, the width of the conductor 28 is larger than the width of the conductor 28 in the first part 48. In particular, the width of the conductor 28 in the second part 50 corresponds to the second width.

In the second part 50, the conductor 28 is straight.

Further, complementing each second part 50 is a conductive plate 51 (shown schematically in dashed lines) of the beam shaping element 26, which is separate from the conductor 28. The conductive plates 51 are spaced apart from the respective corresponding second parts 50 and each form a capacitor with the respective corresponding second part 50.

For example, the conductive plates 51 are located on a different surface or layer of the carrier 30 than the conductor 28 but opposite of the respective corresponding second part 50, and/or the conductive plates 51 have the same size and shape as the respective corresponding second part 50.

In particular, for each of the second parts 50 one corresponding conductive plate 51 is provided. The first part 48 in the second part 50 merge into one another within each transparency section 46.

The neighboring transparency sections 46 are facing each other with their second part 50.

Between the transparency sections 46 an intermediate section 52 corresponding to the center section 42 is provided.

The transparency section 46 has no or only little influence on the behavior of the beam shaping elements 26 in the first frequency band but reduces the scattering and coupling effects of the beam shaping elements 26 for electromagnetic radiation in the second frequency band and/or other frequency bands of the antenna 14. Especially resonances of the beam shaping element 26 in the second and/or other frequency bands can be suppressed.

This is achieved as the transparency sections 46 provide a filter function generated by the capacitors formed by the second parts 50 and the respective corresponding conductive plate 51, in particular in conjunction with the meanders of the first part 48.

It is conceivable that the transparency section 46 are of a different construction, e.g. with different transparency elements, but providing the same filter function.

Figure 6 shows a beam shaping element 26 of a third embodiment of an antenna 14 according to the invention.

The beam shaping element 26 of the third embodiment corresponds to that of the first embodiment, wherein no end sections 44 are provided.

In other words, the conductor 28 has the same width across the entire second portion 34. It is conceivable, that transparency sections 46 are provided in the second portion 34. In this case, the conductor 28 in the second portion 34 has the same width except for the second parts 50 of the transparency sections 46.

Figure 7 shows a beam shaping element 26 of a fourth embodiment of an antenna 14 according to the invention.

In this embodiment, the beam shaping element 26 has an L-shape.

The connection point 36 at the second portion 34 is located at an end of the second portion 34. Thus, the second portion 34 has one free end 38 and a connected end 40.

The connected ends 40 of the first portion 32 and the second portion 34 are electrically connected, in particular galvanically connected and attached to one another at the connection point 36.

Figure 8 shows a fifth embodiment of an antenna 14 in a view similar to that of Figure 2.

In this embodiment, only one row of beam shaping elements 26 is provided. This row of beam shaping elements 26 is located between the columns of the first array 24 and thus corresponds to the third row of beam shaping elements 26 of the antenna 14 according to the first embodiment.

Claims

1. Antenna, in particular for a mobile communication base station (10), comprising a first array (24) of first dual polarized radiators (16) designed for a first frequency band and at least one beam shaping element (26), wherein the at least one beam shaping element (26) comprises a conductor (28) with a first portion (32) extending in a radiation direction (R) of the first array (24) as well as a second portion (34) electrically connected to the first portion (32) at a connection point (36) of the beam shaping element (26) and extending in a direction different from the radiation direction (R), and wherein the conductor (28) of the at least one beam shaping element (26) is ungrounded and has an electrical length between 1/3 and 3/4 of a wavelength of an average frequency of the first frequency band.

2. Antenna according to claim 1, characterized in that the electrical length of the conductor (28) is 1/2 of the wavelength of the average frequency of the first frequency band and/or that the first portion (32) has an electrical length between 1/8 and 3/8 of the wavelength of the average frequency of the first frequency band, in particular of 1/4 of the wavelength of the average frequency of the first frequency band.

3. Antenna according to claim 1 or 2, characterized in that the second portion (34) extends in a direction perpendicular to the radiation direction (R), in particular in the same direction (C) as a column of the first array (24).

4. Antenna according to any of the preceding claims, characterized in that the conductor (28) of the beam shaping element (26) extends in a single plane, in particular in a plane extending in the radiation direction (R) and in a direction (C) of a column of the first array (24).

5. Antenna according to any of the preceding claims, characterized in that the first portion (32) has a free end (38) and a connected end (40), and the second portion (34) has a free end (38) and a connected end (40), wherein the connected ends (40) of the first portion (32) and the second portion (34) are electrically, in particular galvanically connected forming the connection point (36).

6. Antenna according to any of the claims 1 to 4, characterized in that the first portion (32) has a free end (38) and a connected end (40), and the second portion (34) has at least two free ends (38), the connected end (40) of the first portion (32) being electrically, in particular galvanically connected to the second portion (34) at the connection point (36), wherein the connection point (36) is spaced apart from the free ends (38) of the second portion (34).

7. Antenna according to claim 6, characterized in that the connection point (36) is located at the mid-point between the free ends (38) of the second portion (34), and wherein the second portion (34) is symmetric with respect to the connection point (36).

8. Antenna according to any of the claims 5 to 7, characterized in that the electrical length of the conductor (28) is the electrical length between two free ends (38) of the beam shaping element (26), in particular between the free end (38) of the first portion (32) and one free end (38) of the second portion (34).

9. Antenna according to any of the claims 5 to 8, characterized in that the first portion (32) and/or the second portion (34) comprise at least one end section (44) extending from the free end (38) towards the connection point (36) and a center section (42), in particular extending from the connection point (36) towards the respective free end (38), wherein the conductor (28) is larger in width and/or diameter in the end section (44) than in the center section (42).

10. Antenna according to claim 9, characterized in that the physical length of the end section (44) is between 1/2 and 1/4 of the length of the physical distance between the connection point (36) and the respective free end (38).

11. Antenna according to any of the preceding claims, characterized in that the beam shaping element (26) is a metal sheet forming the conductor (28) or comprises a carrier (30) supporting the conductor (28), in particular a PCB or a thermoplastic part supporting the conductor (28).

12. Antenna according to any of the claims 5 to 11, characterized in that the first portion (32) and/or the second portion (34) comprise at least one transparency section (46), in particular wherein the conductor (28) extends in meanders at least in a first part (48) of the transparency section (46) and/or is larger in width than the center section (42) at least in a second part (50) of the transparency section (46).

13. Antenna according to claim 12, characterized in that the beam shaping element (26) comprises at least one conductive plate (51) being separate from the conductor (28) and corresponding to the second part (50) of the transparency section (46), wherein the at least one conductive plate (51) and the corresponding second part (50) form a capacitor, in particular wherein the conductive plate (50) and the second part (50) are located opposite to one another on different surfaces or layers of the carrier (30).

14. Antenna according to any of the preceding claims, characterized in that the beam shaping element (26) is arranged between two of the first radiators (16) of the first array (24), in particular wherein the first array (24) comprises at least two columns with at least two first radiators (16) each, wherein between corresponding first radiators (16) of adjacent columns, one of the at least one beam shaping elements (26) is arranged.

15. Antenna according to any of the preceding claims, characterized in that the antenna (14) comprises at least one further array of radiators designed for a frequency band different from the first frequency band.

16. Mobile communication base station having at least one antenna (14) according to any of the claims 1 to 15.

17. User device for mobile communication having at least one antenna (14) according to any of the claims 1 to 15.