WO2022199854A1

WO2022199854A1 - Beam steering arrangement for electronic apparatus

Info

Publication number: WO2022199854A1
Application number: PCT/EP2021/058004
Authority: WO
Inventors: Janne Ilvonen; Alexander Khripkov; Timofey KAMYSHEV; Ruiyuan TIAN; Dong Liu; Zlatoljub Milosavljevic
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2021-03-26
Filing date: 2021-03-26
Publication date: 2022-09-29

Abstract

A radiation field beam steering arrangement (1) comprising a first conductive element (12), a second conductive element (2) extending adjacent the first conductive element (12) and 5 comprising at least one dielectric coupling structure (3), and at least one end-fire antenna element (4). The end-fire antenna element (4) comprises an antenna radiator (5) configured to generate a radiation field having a main beam direction (D0) oriented parallel to a main plane (P1) of the first conductive element (12). The dielectric coupling structure (3) is configured such that a dielectric gap (13) is formed between the first conductive element (12) and a surface 10 of the second conductive element (2), which gap is transparent to radiation having frequencies within in the millimeter-wave frequency band. Optionally, the overlap between the first conductive element (12) and the second conductive element (2) is small enough to not prevent radiation from passing through the dielectric gap (13).

Description

BEAM STEERING ARRANGEMENT FOR ELECTRONIC APPARATUS

TECHNICAL FIELD

The disclosure relates to a radiation field beam steering arrangement comprising at least one end-fire antenna element and several conductive elements.

BACKGROUND

Mobile apparatuses such as smartphones require omni-coverage dual-polarized mmWave antennas to achieve stable communication in all directions and orientations. However, requirements on the design include the apparatus having a curved design with a sleek metal frame and a large display, with very small clearance therebetween. The frame should preferably not have any visible openings. These requirements are contradictory and thus difficult to achieve in one and the same apparatus.

In one known solution, having a moderately curved display, the end-fire antenna module is positioned towards the dielectric back cover of the apparatus, such that the metal frame of the apparatus does not shadow the antenna. This necessarily limits the battery size, with regards to battery thickness and the required placement of the antenna module. This design provides fairly good end-fire performance, however, the directivity of the antenna is tilted by approximately 30 degrees towards the back cover. Furthermore, the space between the back cover and the display has to be increased when to accommodate the antenna module.

In a further known solution, a more challenging design is provided using a highly curved display. The symmetric glass curvature forces the antenna module to be arranged closer towards the display, which causes the metal frame to shadow the antenna. Furthermore, the antenna has to be arranged closer to the frame in order to allow a sufficiently large battery to be used. Since the antenna is arranged relatively close to the edge, the end-fire directivity would be tilted by up to almost 90 deg and have a wide beam angle.

Hence, there is a need for a solution which provides good end-fire performance and directivity for apparatuses having metal frames and curved displays. SUMMARY

It is an object to provide an improved beam steering arrangement for a handheld device. The foregoing and other objects are achieved by the features of the independent claims. Further implementation forms are apparent from the dependent claims, the description, and the figures.

According to a first aspect, there is provided a radiation field beam steering arrangement comprising a first conductive element, a second conductive element extending adjacent the first conductive element and comprising at least one dielectric coupling structure, and at least one end-fire antenna element. The end-fire antenna element comprises an antenna radiator configured to generate a radiation field having a main beam direction oriented parallel to a main plane of the first conductive element. The dielectric coupling structure is configured such that a dielectric gap is formed between the first conductive element and a surface of the second conductive element, which gap is transparent to radiation having frequencies within in the millimeter-wave frequency band.

Such a beam steering arrangement provides a radiation field which is highly efficient and which does not require tilting of the directivity of the end-fire antenna element even though the end- fire antenna element is arranged relatively close to the conductive elements. Since the directivity of the end-fire antenna element does not need to be tilted towards the back cover of the apparatus, the omni-coverage of the antenna element is improved. Furthermore, the beam steering arrangement can be used together with highly curved display elements, since the dielectric coupling structure allows correct beam steering regardless of the small distances involved.

In a possible implementation form of the first aspect, the dielectric gap extends in a first direction perpendicular to a main plane of the antenna radiator, the dielectric gap being wide enough to allow the millimeter-wave frequency radiation to pass therethrough allowing at least a part of the radiation propagate towards the main beam direction.

In a further possible implementation form of the first aspect, there is no overlap between the first conductive element and the second conductive element along the first direction, allowing radiation to propagate uninterruptedly between components towards the main beam direction. In a further possible implementation form of the first aspect, the first conductive element and the second conductive element partially overlap along the first direction, the overlap being small enough that it does not prevent the millimeter-wave frequency radiation from pass through the dielectric gap. This allows for increased design freedom without deterioration of antenna performance.

In a further possible implementation form of the first aspect, the radiation field beam steering arrangement further comprises a filter element configured to limit the millimeter-wave frequency radiation to frequencies between 24-30 GHz and 37-44 GHz.

In a further possible implementation form of the first aspect, the dielectric coupling structure enables a radiation pattern having a first polarization, the first polarization extending perpendicular to the main beam direction. First polarization such as vertical polarization is made possible as reflection is avoided by means of the dielectric coupling structure.

In a further possible implementation form of the first aspect, the dielectric coupling structure extends in a second direction parallel with the main plane of the antenna radiator(s), and in a third direction parallel with the main plane and perpendicular to the second direction, improving antenna gain by as much as 3 dB.

In a further possible implementation form of the first aspect, a plurality of antenna radiators are aligned to form an array of antenna radiators extending in the second direction, the antenna radiators extending adjacent the dielectric coupling structure(s) such that the main plane of the antenna radiators is parallel with at least a first conductive wall and a second conductive wall partially defining the dielectric coupling structure, improving antenna gain.

In a further possible implementation form of the first aspect, the dielectric coupling structure is defined by the first conductive wall, the second conductive wall, a third conductive wall, and a fourth conductive wall, the third conductive wall and the fourth conductive wall extending, at opposite ends of the dielectric coupling structure, between the first conductive wall and the second conductive wall, using an existing structure to form the dielectric coupling structure. In a further possible implementation form of the first aspect, the dielectric coupling structure has in a U-shape as seen from the main plane of the antenna radiator in the first direction, allowing the dielectric coupling structure to be formed by CNC-machining or similar.

In a further possible implementation form of the first aspect, the antenna arrangement comprises a plurality of antenna elements and the second conductive element comprises one dielectric coupling structure, each antenna radiator being aligned with a section of the dielectric coupling structure in the first direction and in the second direction, enabling vertically polarized end-fire radiation.

In a further possible implementation form of the first aspect, the second conductive element comprises a plurality of dielectric coupling structures, each dielectric coupling structure being aligned with one antenna radiator in the first direction and in the second direction, improving antenna peak directivity.

In a further possible implementation form of the first aspect, the dielectric coupling structure has a larger dimension in the second direction than in the first direction and/or a larger dimension in the second direction than in the third direction, and wherein the dielectric coupling structure has a larger dimension in the third direction than in the first direction, avoiding reflection within the dielectric coupling structure.

In a further possible implementation form of the first aspect, the dielectric coupling structure forms a recess extending partially into the second conductive element in the first direction and in the second direction, while forming a throughgoing opening extending completely through the second conductive element in the third direction, allowing radiation to propagate on two sides of the second conductive element, i.e., both towards and from a user holding the apparatus comprising the beam steering arrangement.

In a further possible implementation form of the first aspect, each dielectric coupling structure has an elongated shape which is one of elliptical and rectangular, allowing the dielectric coupling structure to be configured such that the end-fire gain for one polarization is enhanced without deteriorating the end-fire gain for the other polarization. In a further possible implementation form of the first aspect, the first conductive wall, the second conductive wall, the third conductive wall, and the fourth conductive wall are at least partially straight walls.

In a further possible implementation form of the first aspect, the first conductive wall and the second conductive wall are straight walls interconnected by an at least partially curved third conductive wall and an at least partially curved fourth conductive wall, allowing the dielectric coupling structure to be manufactured using conventional manufacturing technology.

In a further possible implementation form of the first aspect, the dielectric coupling structure has a dimension in the second direction which corresponds to l/2, l being a wavelength at the lowest frequency of the radiation. This assures the end-fire radiation direction and helps avoid parasitic resonance.

In a further possible implementation form of the first aspect, the first conductive wall, extending directly adjacent the antenna radiator, has a first dimension in the third direction, the second conductive wall has a second dimension in the third direction, the second dimension being larger than the first dimension, and the third conductive wall and/or the fourth conductive wall is stepped in the third direction to form a transition between the first conductive wall and the second conductive wall in the third direction, improving the operation of the dielectric coupling structure, in particular wave coupling, by as much as 0.8 dB.

In a further possible implementation form of the first aspect, the step comprises a concave surface.

In a further possible implementation form of the first aspect, adjacent dielectric coupling structures are separated by the third conductive wall or the fourth conductive wall, a section of the third conductive wall and a section of the fourth conductive wall having the second dimension in the third direction, allowing adjacent dielectric coupling structures to be arranged as close as possible yet still being physically separated.

In a further possible implementation form of the first aspect, the second conductive element comprises at least one conductive protrusion extending into at least one of the dielectric coupling structures, improving directivity in high frequency bands such as those between 37- 43 GHz.

In a further possible implementation form of the first aspect, the conductive protrusion is a resonant stub, effectively shortening the length of the dielectric coupling structure at high frequency bands and, hence, improving directivity.

In a further possible implementation form of the first aspect, the conductive protrusion extends from the first conductive wall, the second conductive wall, the third conductive wall, and/or the fourth conductive wall of the dielectric coupling structure, the conductive protrusion(s) extending in the first direction and/or the second direction, allowing the dielectric coupling structure to be adapted to a specific desired configuration.

According to a second aspect, there is provided an apparatus comprising a display element, a back cover, a frame element being arranged at least partially between the display element and the back cover, and the radiation field beam steering arrangement according to the above, the display element comprising the first conductive element of the radiation field beam steering arrangement, the frame element comprising the second conductive element of the radiation field beam steering arrangement.

Such an apparatus comprises an antenna and beam steering arrangement which has a highly efficient radiation field with omni-coverage. The end-fire antenna elements can be arranged relatively close to the conductive elements of the apparatus, freeing up space within the apparatus for, e.g., the battery. Furthermore, the beam steering arrangement can be used together with highly curved display elements, since the dielectric coupling structure allows correct beam steering regardless of the small distances involved.

In a possible implementation form of the second aspect, vertically polarized radiation emitted by the radiation field beam steering arrangement propagates towards the display element and the back cover simultaneously, the dielectric coupling structures of the radiation field beam steering arrangement allowing the vertically polarized radiation to propagate between the display element and the frame element, and between the back cover and the frame element, respectively. In a further possible implementation form of the second aspect, the dielectric coupling structures are covered by the display element, the back cover, and the frame element, such that they are invisible to the naked eye, allowing vertically polarized radiation to propagate through the structures while at least partially protecting the structures from the exterior.

These and other aspects will be apparent from the embodiment s) described below.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following detailed portion of the present disclosure, the aspects, embodiments, and implementations will be explained in more detail with reference to the example embodiments shown in the drawings, in which:

Fig. la shows a partial top view of a radiation field beam steering arrangement in accordance with an example of the embodiments of the disclosure;

Fig. lb shows a cross-sectional view of a radiation field beam steering arrangement in accordance with an example of the embodiments of the disclosure;

Fig. 2a shows a perspective view of an apparatus comprising a radiation field beam steering arrangement in accordance with an example of the embodiments of the disclosure;

Fig. 2b shows a perspective view of an apparatus comprising a radiation field beam steering arrangement in accordance with an example of the embodiments of the disclosure;

Fig. 3 shows a partial perspective view of an apparatus comprising a radiation field beam steering arrangement in accordance with an example of the embodiments of the disclosure;

Fig. 4 shows a partial perspective view of a radiation field beam steering arrangement in accordance with an example of the embodiments of the disclosure;

Fig. 5a shows a partial perspective view of a radiation field beam steering arrangement in accordance with an example of the embodiments of the disclosure; Fig. 5b shows a partial perspective view of a radiation field beam steering arrangement in accordance with an example of the embodiments of the disclosure;

Fig. 6 shows a top view of a dielectric coupling structure in accordance with an example of the embodiments of the disclosure;

Figs. 7a to 7d show top views of dielectric coupling structures in accordance with examples of the embodiments of the disclosure.

DETAILED DESCRIPTION

Fig. 2a shows an apparatus 8, preferably a handheld device such as a smartphone or a tablet, comprising a display element 9, a back cover 10, and a radiation field beam steering arrangement 1 described in more detail below. The apparatus 8 further comprises a frame element 11 arranged at least partially between the display element 9 and the back cover 10.

The display element 9 comprises the first conductive element 12 of the radiation field beam steering arrangement 1 and the frame element 11 comprises the second conductive element 2 of the radiation field beam steering arrangement 1. The frame element 11 may be a metal frame, and the back cover 10 may be a dielectric element made of glass and/or plastic.

The apparatus 8 is configured such that vertically polarized radiation, emitted by the radiation field beam steering arrangement 1, may propagate towards the display element 9 and the back cover 10 simultaneously. As suggested by Figs. 2b and 3, dielectric coupling structures 3 of the radiation field beam steering arrangement 1 allow the vertically polarized radiation to propagate between the display element 9 and the frame element 11, as well as between the back cover 10 and the frame element 11. The dielectric coupling structures 3, in other words, may enable a radiation pattern having a first polarization, such as vertical polarization, the first polarization extending perpendicular to the main beam direction DO. The dielectric coupling structures 3 may be covered by the display element 9, the back cover 10, and the frame element 11, such that they are invisible to the naked eye, as suggested in Fig. 2a.

The radiation field beam steering arrangement 1 comprises a first conductive element 12, a second conductive element 2 extending adjacent the first conductive element 12 and comprising at least one dielectric coupling structure 3, and at least one end-fire antenna element 4 comprising an antenna radiator 5 configured to generate a radiation field having a main beam direction DO oriented parallel to a main plane PI of the first conductive element 12. The dielectric coupling structure 3 is configured such that a dielectric gap 13 is formed between the first conductive element 12 and a surface of the second conductive element 2, which gap is transparent to radiation having frequencies within in the millimeter-wave frequency band.

The radiation field beam steering arrangement 1 may comprise a filter element configured to limit the millimeter-wave frequency radiation to frequencies between 24-30 GHz and 37-44 GHz.

The first conductive element 12, which may be the display element 9 of the apparatus 8 as mentioned above, may be partially curved, preferably along its edges. The main plane PI of the first conductive element 12 corresponds to the main flat surface of the display element 9.

The second conductive element 2 extends adjacent the first conductive element 12, and may be, or be comprised in, the frame element 11 of the apparatus 8 as mentioned above. The first conductive element 12 and the second conductive element 2 may be arranged such that there is no overlap between the first conductive element 12 and the second conductive element 2 (not shown) along a first direction Dl. Optionally, the first conductive element 12 and the second conductive element 2 may be arranged such that they partially overlap along the first direction Dl, as shown in Figs 2a and 3, the overlap being small enough that it does not prevent the millimeter-wave frequency radiation from propagating between the first conductive element 12 and the second conductive element 2 towards the exterior of the apparatus 8.

The second conductive element 2 comprises at least one dielectric coupling structure 3. The dielectric coupling structure 3 is configured such that a dielectric gap 13 is formed between the first conductive element 12 and a surface of the second conductive element 2, which gap is transparent to radiation having frequencies within in the millimeter-wave frequency band. The above-mentioned overlap between the first conductive element 12 and the second conductive element 2 is small enough that it does not prevent the millimeter- wave frequency radiation from passing through the dielectric gap 13. The dielectric coupling structure 3 may be filled with a dielectric material such as plastic, providing support to the second conductive element 2 such that it remains sturdy. Optionally, the dielectric coupling structure 3 may be formed by a void, i.e. be filled with air. The radiation field beam steering arrangement 1 furthermore comprises at least one end-fire antenna element 4. The antenna radiator 5 of the end-fire antenna element 4 is configured to generate the above-mentioned radiation field having a main beam direction DO oriented parallel to a main plane PI of the first conductive element 12, as shown in Figs lb and 2a.

The dielectric gap 13 between the first conductive element 12 and the second conductive element 2 may extend in a first direction D1 perpendicular to a main plane P2 of the antenna radiator 5, as shown in Figs. 2a to 3. The dielectric gap 13 is wide enough to allow the millimeter-wave frequency radiation to pass therethrough.

The dielectric coupling structure 3 may extend in a second direction D2 parallel with the main plane P2 of the antenna radiators 5, and in a third direction D3 parallel with the main plane P2 and perpendicular to the second direction D2, as shown in Figs la, 2a, and 3 to 5b. In other words, the dielectric coupling structure 3 may have a depth along the first direction Dl, a length along the second direction D2, and a height along the third direction D3.

The dielectric coupling structure 3 may have a dimension in the second direction D2, i.e. a length, which corresponds to l/2, l being the wavelength at the lowest frequency of the radiation.

The dielectric coupling structure 3 may have a larger dimension in the second direction D2 than in the first direction Dl and/or a larger dimension in the second direction D2 than in the third direction D3. The dielectric coupling structure 3 may also have a larger dimension in the third direction D3 than in the first direction Dl. In other words, the dielectric coupling structure 3 may have a length which is longer than its depth and/or height. The dielectric coupling structure 3 may have an elongated shape which is one of elliptical and rectangular.

The dielectric coupling structure 3 may be configured to form a recess extending partially into the second conductive element 2 in the first direction Dl and in the second direction D2, while forming a throughgoing opening extending completely through the second conductive element 2 in the third direction D3. The dielectric coupling structure 3 may be defined by a first conductive wall 6a, a second conductive wall 6b, a third conductive wall 6c, and a fourth conductive wall 6d, as shown in Figs. 5a and 5b. The third conductive wall 6c and the fourth conductive wall 6d may extend at opposite ends of the dielectric coupling structure 3 between the first conductive wall 6a and the second conductive wall 6b.

The first conductive wall 6a, the second conductive wall 6b, the third conductive wall 6c, and the fourth conductive wall 6d may be at least partially straight walls. The first conductive wall 6a and the second conductive wall 6b may be straight walls interconnected by an at least partially curved third conductive wall 6c and an at least partially curved fourth conductive wall 6d, as shown in Figs. 5a and 5b.

The first conductive wall 6a may extend directly adjacent the antenna radiator 5 and have a first dimension dl in the third direction D3. Correspondingly, the second conductive wall 6b may have a second dimension d2 in the third direction D3, the second dimension d2 being larger than the first dimension dl. The third conductive wall 6c and/or the fourth conductive wall 6d may stepped in the third direction D3, the step optionally comprising a concave surface as shown in Fig. 5a, to form a smooth transition between the first conductive wall 6a and the second conductive wall 6b in the third direction D3.

Adjacent dielectric coupling structures 3 may be separated by the third conductive wall 6c and/or the fourth conductive wall 6d, such that a section of the third conductive wall 6c and a section of the fourth conductive wall 6d have the second dimension d2 in the third direction D3. The third conductive wall 6c of one dielectric coupling structure 3 may correspond to the fourth conductive wall 6d of an adjacent dielectric coupling structure 3, and the opposite.

A plurality of antenna radiators 5 may be aligned to form an array of antenna radiators 5 extending in the second direction D2, as suggested in Figs lb and 4. At least one antenna radiator 5 extends adjacent at least one dielectric coupling structure 3 such that the main plane P2 of the antenna radiator 5 is parallel with at least the first conductive wall 6a and the second conductive wall 6b partially defining the dielectric coupling structure 3. The dielectric coupling structure 3 may have in a U-shape as seen from the main plane P2 of the antenna radiator 5 in the first direction Dl . The radiation field beam steering arrangement 1 may comprise a plurality of antenna elements 4, and the second conductive element 2 may correspondingly comprise a plurality of dielectric coupling structures 3, each dielectric coupling structure 3 being aligned with one antenna radiator 5 and/or one antenna element 4 in the first direction D1 and in the second direction D2, as shown in Figs lb and 3.

Optionally, the second conductive element 2 may comprise only one dielectric coupling structure 3. Each antenna radiator 5 of the plurality of antenna elements 4 is aligned with a section of the dielectric coupling structure 3 in the first direction D1 and in the second direction D2 (not shown).

The second conductive element 2 may comprise at least one conductive protrusion 7 extending into at least one of the dielectric coupling structures 3. The conductive protrusion 7 may be a resonant stub.

The conductive protrusion 7 may extends from the first conductive wall 6a of the dielectric coupling structure 3, as shown in Figs. 7a to 7c, from the second conductive wall 6b, as shown in Figs. 6 to 7c, from the third conductive wall 6c (not shown), and/or from the fourth conductive wall 6d, as shown in Fig. 7d. The conductive protrusions 7 may extend in the first direction D1 and/or in the second direction D2.

The various aspects and implementations have been described in conjunction with various embodiments herein. However, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed subject-matter, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage.

The reference signs used in the claims shall not be construed as limiting the scope. Unless otherwise indicated, the drawings are intended to be read (e.g., cross-hatching, arrangement of parts, proportion, degree, etc.) together with the specification, and are to be considered a portion of the entire written description of this disclosure. As used in the description, the terms “horizontal”, “vertical”, “left”, “right”, “up” and “down”, as well as adjectival and adverbial derivatives thereof (e.g., “horizontally”, “rightwardly”, “upwardly”, etc.), simply refer to the orientation of the illustrated structure as the particular drawing figure faces the reader. Similarly, the terms “inwardly” and “outwardly” generally refer to the orientation of a surface relative to its axis of elongation, or axis of rotation, as appropriate.

Claims

1. A radiation field beam steering arrangement (1) comprising:

-a first conductive element (12);

-a second conductive element (2) extending adjacent said first conductive element (12) and comprising at least one dielectric coupling structure (3);

-at least one end-fire antenna element (4) comprising an antenna radiator (5) configured to generate a radiation field having a main beam direction (DO) oriented parallel to a main plane (PI) of the first conductive element (12), said dielectric coupling structure (3) being configured such that a dielectric gap (13) is formed between said first conductive element (12) and a surface of said second conductive element (2), which gap is transparent to radiation having frequencies within in the millimeter-wave frequency band.

2. The radiation field beam steering arrangement (1) according to claim 1, wherein said dielectric gap (13) extends in a first direction (Dl) perpendicular to a main plane (P2) of said antenna radiator (5), said dielectric gap (13) being wide enough to allow said millimeter-wave frequency radiation to pass therethrough.

3. The radiation field beam steering arrangement (1) according to claim 1 or 2, further comprising a filter element configured to limit said millimeter- wave frequency radiation to frequencies between 24-30 GHz and 37-44 GHz.

4. The radiation field beam steering arrangement (1) according to claim 2 or 3, wherein said dielectric coupling structure (3) extends in a second direction (D2) parallel with said main plane (P2) of said antenna radiator(s) (5), and in a third direction (D3) parallel with said main plane (P2) and perpendicular to said second direction (D2).

5. The radiation field beam steering arrangement (1) according to claim 4, wherein a plurality of antenna radiators (5) are aligned to form an array of antenna radiators (5) extending in said second direction (D2), said antenna radiators (5) extending adjacent said dielectric coupling structure(s) (3) such that said main plane (P2) of said antenna radiators (5) is parallel with at least a first conductive wall (6a) and a second conductive wall (6b) partially defining said dielectric coupling structure (3).

6. The radiation field beam steering arrangement (1) according to claim 5, wherein said dielectric coupling structure (3) is defined by said first conductive wall (6a), said second conductive wall (6b), a third conductive wall (6c), and a fourth conductive wall (6d), said third conductive wall (6c) and said fourth conductive wall (6d) extending, at opposite ends of said dielectric coupling structure (3), between said first conductive wall (6a) and said second conductive wall (6b).

7. The radiation field beam steering arrangement (1) according to any one of claims 4 to 6, wherein said second conductive element (2) comprises a plurality of dielectric coupling structures (3), each dielectric coupling structure (3) being aligned with one antenna radiator (5) in said first direction (Dl) and in said second direction (D2).

8. The radiation field beam steering arrangement (1) according to any one of claims 4 to 7, wherein said dielectric coupling structure (3) has a larger dimension in said second direction (D2) than in said first direction (Dl) and/or a larger dimension in said second direction (D2) than in said third direction (D3), and wherein said dielectric coupling structure (3) has a larger dimension in said third direction (D3) than in said first direction (Dl).

9. The radiation field beam steering arrangement (1) according to any one of claims 4 to 8, wherein said dielectric coupling structure (3) forms a recess extending partially into said second conductive element (2) in said first direction (Dl) and in said second direction (D2), while forming a throughgoing opening extending completely through said second conductive element (2) in said third direction (D3).

10. The radiation field beam steering arrangement according to any one of claims 4 to 9, wherein said dielectric coupling structure (3) has a dimension in said second direction (D2) which corresponds to l/2, l being a wavelength at the lowest frequency of said radiation.

11. The radiation field beam steering arrangement according to any one of claims 6 to 9, wherein said first conductive wall (6a), extending directly adjacent said antenna radiator (5), has a first dimension (dl) in said third direction (D3), said second conductive wall (6b) has a second dimension (d2) in said third direction (D3), said second dimension (d2) being larger than said first dimension (dl), and said third conductive wall (6c) and/or said fourth conductive wall (6d) is stepped in said third direction (D3) to form a transition between said first conductive wall (6a) and said second conductive wall (6b) in said third direction (D3).

12. The radiation field beam steering arrangement (1) according to claim 11, wherein adjacent dielectric coupling structures (3) are separated by said third conductive wall (6c) or said fourth conductive wall (6d), a section of said third conductive wall (6c) and a section of said fourth conductive wall (6d) having said second dimension (d2) in said third direction (D3).

13. The radiation field beam steering arrangement (1) according to any one of the previous claims, wherein said second conductive element (2) comprises at least one conductive protrusion (7) extending into at least one of said dielectric coupling structures (3).

14. The radiation field beam steering arrangement (1) according to claim 13, wherein said conductive protrusion (7) extends from said first conductive wall (6a), said second conductive wall (6b), said third conductive wall (6c), and/or said fourth conductive wall (6d) of said dielectric coupling structure (3), said conductive protrusion(s) (7) extending in said first direction (Dl) and/or said second direction (D2).

15. An apparatus (8) comprising a display element (9), a back cover (10), a frame element (11) being arranged at least partially between said display element (9) and said back cover (10), and the radiation field beam steering arrangement (1) according to any one of claims 1 to 14, the display element (9) comprising the first conductive element (12) of said radiation field beam steering arrangement (1), the frame element (11) comprising the second conductive element (2) of said radiation field beam steering arrangement (1).

16. The apparatus (8) according to claim 15, wherein vertically polarized radiation emitted by said radiation field beam steering arrangement (1) propagates towards said display element (9) and said back cover (10) simultaneously, the dielectric coupling structures (3) of said radiation field beam steering arrangement (1) allowing said vertically polarized radiation to propagate between said display element (9) and said frame element (11), and between said back cover (10) and said frame element (11), respectively.