DUAL-POLARIZATION ANTENNA ARRAY

Abstract

Embodiments of the present invention provide a dual-polarization antenna array that includes: a conductive structure having an aperture pattern including at least one first aperture and at least one second aperture, the first aperture(s) being directly interconnected with at least one second aperture. At least one first coupling element is connected to a first antenna feed line to excite a first electrical field having a first polarization. At least one second coupling element is connected to a second antenna feed line to excite a second electrical field having a second polarization. Each first coupling element is at least partially juxtaposed with one first aperture, allowing said first electrical field to be transmitted and/or received through said first aperture. Each second coupling element being at least partially juxtaposed with one second aperture, allowing said second electrical field to be transmitted and/or received through said second aperture.

Claims

1-17. (canceled)

18. A dual-polarization antenna array, comprising: a conductive structure, having an aperture pattern comprising at least one first aperture having a first configuration and at least one second aperture having a second configuration, wherein the at least one first aperture is directly interconnected with at least one second aperture; at least one first coupling element connected to a first antenna feed line; and at least one second coupling element connected to a second antenna feed line, wherein the at least one first coupling element is configured to excite a first electrical field having a first polarization, wherein the at least one second coupling element is configured to excite a second electrical field having a second polarization, wherein each first coupling element is at least partially juxtaposed with one first aperture, allowing the first electrical field having the first polarization to be transmitted or received through the first aperture, and wherein each second coupling element is at least partially juxtaposed with one second aperture, allowing the second electrical field having the second polarization to be transmitted or received through the second aperture.

19. The dual-polarization antenna array according to claim 18, wherein the first aperture has a larger area than the second aperture, wherein the first coupling element is configured to excite an electrical field having horizontal polarization, and wherein the second coupling element is configured to excite an electrical field having vertical polarization.

20. The dual-polarization antenna array according to claim 18, wherein a first end of the second coupling element is connected to the second antenna feed line at one side of the second aperture, and wherein a second end of the second coupling element is coupled to the conductive structure at an opposite side of the second aperture.

21. The dual-polarization antenna array according to claim 20, wherein the second end of the second coupling element is at least one of galvanically, inductively, and capacitively coupled to the conductive structure.

22. The dual-polarization antenna array according to claim 18, wherein a first end of the first coupling element is connected to the first antenna feed line at one side of the second aperture, and wherein a second end of the first coupling element is at least partially juxtaposed with the first aperture adjacent to the second aperture.

23. The dual-polarization antenna array according to claim 22, wherein the second end of the first coupling element is offset from the first end of the first coupling element in a direction towards to an adjacent second aperture.

24. The dual-polarization antenna array according to claim 18, wherein the first coupling element and the second coupling element are connected to one of an unbalanced antenna feed line and a balanced antenna feed line.

25. The dual-polarization antenna array according to claim 18, further comprising at least two first apertures and at least one second aperture, wherein the least two first apertures and the at least one second aperture are arranged in periodic sequence such that each first aperture is separated from an adjacent first aperture by a second aperture, and wherein each second aperture is directly interconnected with two adjacent first apertures.

26. The dual-polarization antenna array according to claim 25, wherein the first coupling elements and the second coupling elements are arranged such that every other second aperture is at least partially juxtaposed with a second coupling element and every other second aperture is at least partially juxtaposed with a first coupling element, and wherein each first coupling element additionally is at least partially juxtaposed with one first aperture adjacent to the second aperture.

27. The dual-polarization antenna array according to claim 18, wherein one first coupling element and one second coupling element are at least partially juxtaposed with one second aperture.

28. The dual-polarization antenna array according to claim 27, wherein the aperture pattern comprises at least one H-pattern, each H-pattern comprising two first apertures and one second aperture directly interconnecting the first apertures.

29. An electronic device, comprising: a display, a device chassis, and a dual-polarization antenna array, further comprising: a conductive structure, having an aperture pattern comprising at least one first aperture having a first configuration and at least one second aperture having a second configuration, wherein the at least one first aperture(s) is directly interconnected with at least one second aperture; at least one first coupling element being connected to a first antenna feed line; and at least one second coupling element being connected to a second antenna feed line, wherein the at least one first coupling element is configured to excite a first electrical field having a first polarization, wherein the at least one second coupling element is configured to excite a second electrical field having a second polarization, wherein each first coupling element is at least partially juxtaposed with one first aperture, allowing the first electrical field having the first polarization to be transmitted or received through the first aperture, wherein each second coupling element is at least partially juxtaposed with one second aperture, allowing the second electrical field having the second polarization to be transmitted or received through the second aperture, wherein the conductive structure of the dual-polarization antenna array comprises a metal frame, wherein the device chassis is at least partially enclosed by the display and the metal frame, wherein first coupling elements and second coupling elements of the dual-polarization antenna array are coupled to the metal frame.

30. The electronic device according to claim 29, wherein the conductive structure further comprises a printed circuit board extending at least partially in parallel with the metal frame, between the metal frame and the device chassis, wherein the first coupling elements and the second coupling elements of the dual-polarization antenna array are arranged on the printed circuit board.

31. The electronic device according to claim 29, further comprising a reflecting structure extending in parallel with the at least one first aperture and the at least one second aperture of the conductive structure.

32. The electronic device according to claim 29, wherein the dual-polarization antenna array is configured to generate millimeter-wave frequencies.

33. The electronic device according to claim 32, wherein the dual-polarization antenna array comprises at least one end-fire antenna element.

34. The electronic device according to claim 29, further comprising at least one further antenna configured by the device chassis and the metal frame with feed lines extending partially adjacent to the dual-polarization antenna array and partially across a gap between the device chassis and the metal frame, the further antenna generating non-millimeter-wave frequencies.

35. The electronic device according to claim 29, wherein a first end of the second coupling element is connected to the second antenna feed line at one side of the second aperture, wherein a second end of the second coupling element is coupled to the conductive structure at an opposite side of the second aperture.

36. The dual-polarization antenna array according to claim 29, wherein a first end of the first coupling element is connected to the first antenna feed line at one side of the second aperture, and wherein a second end of the first coupling element is at least partially juxtaposed with the first aperture adjacent to the second aperture.

37. The dual-polarization antenna array according to claim 36, wherein the second end of the first coupling element is offset from the first end of the first coupling element in a direction towards to an adjacent second aperture.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] 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:

[0028] FIGS. 1a to 1c show schematic illustrations of aperture patterns used in a dual-polarization antenna array according to an embodiment of the application;

[0029] FIG. 2a shows a schematic perspective view of a dual-polarization antenna array according to an embodiment of the application;

[0030] FIG. 2b shows a schematic perspective view of a dual-polarization antenna array according to an embodiment of the application;

[0031] FIG. 3a is a further schematic illustration of the embodiment of FIG. 1a;

[0032] FIG. 3b shows a schematic illustration of an aperture pattern used in a dual-polarization antenna array according to an embodiment of the application;

[0033] FIG. 4 is a further schematic illustration of the embodiment of FIG. 3b, indicating a possible relationship between different dimensions according to an embodiment of the application;

[0034] FIG. 5a shows a partial perspective view of a dual-polarization antenna array according to an embodiment of the application;

[0035] FIG. 5b shows a schematic top view of a dual-polarization antenna array according to an embodiment of the application;

[0036] FIG. 5c shows a partial perspective view of the embodiments of FIGS. 5a and 5b in more detail according to an embodiment of the application;

[0037] FIG. 6a shows a partial perspective view of a dual-polarization antenna array according to an embodiment of the application;

[0038] FIG. 6b shows a partial exploded view of the embodiment of FIG. 6a;

[0039] FIG. 7 shows a schematic cross-sectional view of an electronic device according to an embodiment of the application.

[0040] FIG. 8a shows a partial perspective view an electronic device with a conductive structure according to an embodiment of the application;

[0041] FIG. 8b shows a front view of the embodiment of FIG. 8a according to an embodiment of the application;

[0042] FIG. 9 shows a schematic cross-sectional view of an electronic device and the radiation of the electromagnetic field generated by the electronic device according to an embodiment of the application.

DETAILED DESCRIPTION

[0043] FIGS. 8a and 8b show an embodiment of an electronic device 9, such as a mobile phone or a tablet, comprising a display 10, a device chassis 11, and a dual-polarization antenna array 1 which includes a conductive structure 2, comprising a metal frame 14 and a PCB 12, having an aperture pattern.

[0044] The aperture pattern, shown schematically in FIGS. 1a to 1c, comprises at least one first aperture 3 having a first configuration and at least one second aperture 4 having a second configuration. Each first aperture 3 is directly interconnected with at least one second aperture 4. The aperture pattern may comprise of essentially rectangular shapes, as shown in FIG. 2a, of essentially elliptical shapes, having rounded corners as shown in FIG. 2b, a combination of both, or any other suitable shape. FIG. 3a shows a dual-polarization antenna array 1 comprising a larger number of first apertures 3, each pair of two first apertures 3 being interconnected by one second aperture 4 such that a chain-like structure is formed.

[0045] In one embodiment, the dual-polarization antenna array 1 comprises at least two first apertures 3 and at least one second aperture 4, the first apertures 3 and the second aperture 4 being arranged in periodic sequence such that each first aperture 3 is separated from an adjacent first aperture 3 by a second aperture 4, and each second aperture 4 is directly interconnected with two adjacent first apertures 3. FIG. 3b shows a dual-polarization antenna array 1 comprising two first apertures 3 and one second aperture 4 directly interconnecting the two first apertures 3, i.e. the aperture pattern of FIG. 3b comprises two H-patterns. The dual-polarization antenna array 1 may comprise only one such H-pattern, pattern, or several subsequent H-patterns as shown in FIG. 4.

[0046] The dual-polarization antenna array 1 further comprises at least one first coupling element, i.e. conductor, 5 which is connected to a first antenna feed line 6, and at least one second coupling element, i.e. conductor, 7 which is connected to a second antenna feed line 8, as shown in FIGS. 5a to 5c and 8a to 8b.

[0047] In one embodiment, shown in FIGS. 5a to 5c, the first coupling elements 5 and the second coupling elements 7 are arranged such that every other second aperture 4 is at least partially juxtaposed with a second coupling element 7 and every other second aperture 4 is at least partially juxtaposed with a first coupling element 5. Each first coupling element 5 is additionally at least partially juxtaposed with one first aperture 3 adjacent the second aperture 4.

[0048] The first coupling element 5 is configured to excite an electrical field having a first polarization, and the second coupling element 7 is configured to excite an electrical field having a second polarization. Each first coupling element 5 is at least partially juxtaposed with one first aperture 3, which allows the electrical field having a first polarization to be transmitted and/or received through the first aperture 3. Correspondingly, each second coupling element 7 is at least partially juxtaposed with one second aperture 4, which allows the electrical field having a second polarization to be transmitted and/or received through the second aperture 4.

[0049] In one embodiment, the first aperture 3 has a larger area than the second aperture 4, and the first coupling element 5 is configured to excite an electrical field having horizontal polarization, while the second coupling element 7 is configured to excite an electrical field having vertical polarization, as shown in FIG. 5c.

[0050] The first end 7a of the second coupling element 7 may be connected to the second antenna feed line 8 at one side of the second aperture 4, while the second end 7b of the second coupling element 7 is coupled to the conductive structure 2 at an opposite side of the second aperture 4, as shown clearly in FIG. 5c. The second end 7b of the second coupling element 7 is at least one of galvanically, inductively, and capacitively coupled to the conductive structure 2.

[0051] Correspondingly, the first end 5a of the first coupling element 5 may be connected to the first antenna feed line 6 at one side of the second aperture 4, while the second end 5b of the first coupling element 5 is at least partially juxtaposed with one of the first apertures 3, which first aperture 3 is located adjacent the second aperture 4. The second end 5b of the first coupling element 5 is offset from the first end 5a of the first coupling element 5 in a direction towards a further, adjacent second aperture 4, as shown in FIG. 5c.

[0052] FIG. 5c shows a first coupling element 5 where the second end 5b extends only in one direction.

[0053] An unbalanced feed line 6a, 8a is connected to different types of conductors, i.e. coupling elements 5, 7, for differently polarized currents. For instance, the return current may flow through a common ground or other conductive parts. An unbalanced feed line 6a, 8a inherently couples to the common ground, which typically results into a significant mutual coupling between closely-located unbalanced feeds. To lower the mutual coupling between the feed lines 6a, 8a, they are typically physically offset, as shown in FIGS. 5a to 5c). For instance, if λ/2 element separation is desired in a dual-polarized array, the distance between differently polarized feed lines 6a, 8a can be λ/4. Hereinafter λ is the wavelength at center frequency of the dual-polarization antenna array 1.

[0054] FIG. 5b shows preferable dimensions of the dual-polarization antenna array 1. L1, λ/4˜λ/2, defines the inter-element spacing which will affect the directivity of the array and define the maximum grating-lobe free steering range. L2, λ/4˜λ/2, defines the lowest operational frequency for the horizontal polarization. L3, approximately λ/4, defines the probe length which defines the resonant frequency for the horizontal polarization. L4, λ/15-λ/4, defines the conductor length which defines the resonant frequency for the vertical polarization, i.e. the length of the second coupling element 7 which extends across the second aperture 4. L5, λ/15-λ/4, defines the gap between two opposite “teeth” of the dual-polarization antenna array 1, which is modified to, in turn, modify the resonant frequency.

[0055] In a further embodiment, shown in FIG. 6a, 6b, the first coupling elements 5 and the second coupling elements 7 are arranged such that both one first coupling element 5 and one second coupling element 7 are at least partially juxtaposed with one second aperture 4, the first coupling element 5 and the second coupling element 7 being co-located.

[0056] The first coupling element 5 and the second coupling element 7 may also be connected to balanced feed lines 6b, 8b. As shown in FIG. 6a, 6b, the first coupling element 5 may comprise two conductors, i.e. two second ends 5b extending in two opposite directions, providing balanced excitation of two adjacent first apertures 3. Geometrically, a balanced feed line 6b, 8b is symmetrical and therefore the conductors for positive and negative currents are identical, as is clear from FIGS. 6a, 6b. Furthermore, both conductors couple equally to the conductive structure 2 and to other parts. Ideally, the differential mode of a balanced feed line does not couple to the conductive structure 2, or other nearby metal objects at all. Therefore, two orthogonally-polarized balanced feed lines 6b, 8b can be co-located, both feed lines being mutually uncoupled as shown in FIG. 6b). This embodiment improves the isolation and cross-polarization levels of each feed line. A balanced solution may rely on capacitive coupling from the second end 7b of the second coupling element 7 to the conductive structure 2.

[0057] One of first coupling element 5 and the second coupling element 7 may be connected to a balanced feed line 6a, 8a while the other coupling element is connected to an unbalanced feed line 6a, 8a, regardless of the first coupling element 5 and the second coupling element 7 being co-located or not.

[0058] Regardless whether the feed line 6, 8, and hence the coupling element 5, 7 is balanced or unbalanced, the coupling element 5, 7 can couple to the conductive structure 2 galvanically, capacitively or inductively. In galvanic coupling, either both ends of a balanced feed line 6a, 8a,or signal and ground conductors in case of an unbalanced feed line 6b, 8b, are galvanically connected to the conductive structure 2. This embodiment is most feasible with an unbalanced vertically polarized feed line, but can be used in other cases too. An unbalanced vertically polarized feed line 8b could also be realized with a capacitive coupling. In this case the signal would be coupled to certain area of the conductive structure 2 through a large parallel-plate capacitor at the second end 7b, as well as the ground coupling pad. This would facilitate the fabrication process since no galvanic connection is needed.

[0059] In a further embodiment, the coupling could also be done by utilizing magnetic fields such that currents in the feed line 6, 8 induce currents on the conductive structure 2.

[0060] As mentioned above, and shown in FIG. 7, the electronic device 9 comprises a display 10, a device chassis 11, and a dual-polarization antenna array 1. The conductive structure 2 of the dual-polarization antenna array 1 comprises at least a metal frame 14, and the device chassis 11 is at least partially enclosed by the display 10 and the metal frame 14. The first coupling elements 5 and second coupling elements 7 of the dual-polarization antenna array 1 are coupled to the metal frame 14.

[0061] The conductive structure 2 may furthermore comprise a PCB 12. The first coupling elements 5 and second coupling elements 7 of the dual-polarization antenna array 1 are arranged on the PCB 12 which extends at least partially in parallel with the metal frame 14, between the metal frame 14 and the device chassis 11. The coupling elements 5, 7, when realized on the PCB 12, are relatively easy and inexpensive to manufacture.

[0062] In one embodiment, the first coupling elements 5, the second coupling elements 7, and the conductive structure 2 are configured using at least one of molded interconnect device technology, laser direct structuring technology, flexible printed circuits, metal-spraying techniques and related technologies.

[0063] The aperture pattern in the metal frame 14 can be filled with dielectric material such as plastic for robustness and sealing purposes.

[0064] In one embodiment, the electronic device 9 comprises a reflecting structure 13 extending in parallel with the at least one first aperture 3 and the at least one second aperture 4 of the conductive structure 2, as shown in FIGS. 5a and 7. The reflecting structure 13 may be an existing component of the electronic device 9, such as the device chassis 11, a battery, a shielding structure, or another conductive component. The reflecting structure 13 may be located at approximately λ/4 from the aperture pattern at the conductive structure 2 in order to direct radiation outwards from the electronic device.

[0065] The dual-polarization antenna array 1 may be configured to generate millimeter-wave frequencies. Furthermore, the dual-polarization antenna array 1 may comprise at least one end-fire antenna element.

[0066] The electronic device 9 may also comprise at least one further antenna array 16 configured to generate non-millimeter-wave frequencies, e.g. a sub-6 GHz antenna being part of the metal frame 14. The further antenna array 16 is configured by the device chassis 11 and the metal frame 14 with feed lines 17 extending partially adjacent the dual-polarization antenna array 1 and partially across a gap 15 formed between the device chassis 11 and the metal frame 14.

[0067] The communication performance of the electronic device 9 is further improved by beamforming directed along the edges the electronic device in the directions indicated by the arrows in FIG. 7. The edges of the metal frame 14 are exposed to free-space in typical user scenarios. Steering the dual-polarization beams in these directions enables omnicoverage.

[0068] The present disclosure allows the size of the apertures in the metal frame 14, and the antenna thickness Lt, shown in FIG. 7 to be reduced, from as common in prior art λ/2 (4-5 mm) and λ/4 (2 mm) to λ/20 (0.5 mm), i.e. a reduction by about 40% and 80%, respectively. In one embodiment, the necessary aperture height is 3 mm. In a further embodiment, the antenna thickness, in the direction of the gap 15, is Lt=0.3 mm.

[0069] As mentioned above, the conductive structure 2 of the dual-polarization antenna array 1 may be configured by the metal frame 14 and the PCB 12, as shown in FIGS. 8a and FIG. 8b, where dielectric structures are hidden for the sake of clarity. The aperture patterns of the conductive structure 2 are configured as follows: the second apertures 4 are defined by metallization layers of the PCB 12, and the first apertures 3 are defined by metallization layers of the PCB 12 and an aperture in the metal frame 14. This solution enables the coexistence of sub-6 GHz antennas with 5G mm-wave antennas: both sub 6-GHz antennas 16 and the millimeter-wave dual-polarization antenna array 1 share the same volume of the metal frame 14 and the same volume of the gap 15 between the metal frame 14 and the chassis 11. The aperture pattern of the metal frame 14 does not degrade performance of the sub 6-GHz antennas 16.

[0070] The radiation of the electromagnetic field generated by the electronic device 9 is shown in FIG. 9. Lines of equal electric potential are illustrated for the horizontal polarization radiation, which is generated by first coupling elements 5. A reactive electric field is generated within the gap 15, between the device chassis 11 and the metal frame 14, illustrating efficient usage of the gap 15 volume for bandwidth and antenna efficiency improvement. At the same time, the dual-polarization array 1 does not require any conductive structures present within the gap 15, thus enabling coexistence with the above-mentioned further antenna array 16 which generates non-millimeter-wave frequencies, as shown in FIG. 7.

[0071] The various aspects and implementations has 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 operations, 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.

[0072] The reference signs used in the claims shall not be construed as limiting the scope.