The present invention relates to the field of antenna technologies, and in particular, to a dual-band dual-polarized millimeter-wave antenna.
With development of the fifth generation mobile communications technology, a millimeter-wave frequency band is formally used. For example, two millimeter-wave frequency bands in the United States are respectively 28 GHz and 39 GHz. To meet operators' requirements, antennas of communications products (such as smart phones and notebook computers) should cover both the millimeter-wave frequency bands. However, so far, there is no design of a dual-band dual-polarized millimeter-wave antenna in the industry.
Embodiments of this application provide a design of a dual-band dual-polarized millimeter-wave antenna.
According to a first aspect, this application provides a millimeter-wave antenna array element, including a ground layer, a first dielectric layer, a first radiation patch, a second dielectric layer, and a second radiation patch that are sequentially stacked, the millimeter-wave antenna array element further includes a first feeding part and a second feeding part; at least a part of the first feeding part is disposed inside the first dielectric layer, or inside the second dielectric layer, or between the first dielectric layer and the second dielectric layer, and the first feeding part is insulated from the first radiation patch, the second radiation patch, and the ground layer; at least a part of the second feeding part is disposed inside the first dielectric layer, or inside the second dielectric layer, or between the first dielectric layer and the second dielectric layer, and the second feeding part is insulated from the first feeding part, the first radiation patch, the second radiation patch, and the ground layer; and the first feeding part and the second feeding part are electrically connected to a feed, to excite electromagnetic wave signals of two frequency bands to each of the first radiation patch and the second radiation patch. Specifically, the electromagnetic wave signals are excited through spatial coupling. In addition, electromagnetic wave signals with two polarizations are generated on each of the first radiation patch and the second radiation patch. In other words, electromagnetic wave signals with two polarizations are generated on the first radiation patch. Specifically, orthogonally polarized electromagnetic wave signals are generated on the first radiation patch, and orthogonally polarized electromagnetic wave signals are also generated on the second radiation patch.
For example, the electromagnetic wave signals of the two frequency bands may be electromagnetic wave signals of a frequency band range of 26.5 GHz to 29.5 GHz and electromagnetic wave signals of a frequency band range of 37.0 GHz to 40.5 GHz.
In this application, the first feeding part and the second feeding part are disposed, the first feeding part is spatially coupled to the first radiation patch and the second radiation patch, and the second feeding part is spatially coupled to the first radiation patch and the second radiation patch, so that electromagnetic wave signals with two different polarizations of a first frequency band are excited on the first radiation patch, and electromagnetic wave signals with two different polarizations of a second frequency band are excited on the second radiation patch. In this way, the millimeter-wave antenna array element provided in this application can be dual-band and dual-polarized. Specifically, a frequency of an electromagnetic wave signal on the first radiation patch is lower than a frequency of an electromagnetic wave signal on the second radiation patch, the first radiation patch is a low-frequency radiator, and the second radiation patch is a high-frequency radiator.
In an implementation, when at least a part of the first feeding part and at least a part of the second feeding part are disposed between the first dielectric layer and the second dielectric layer, the first feeding part includes a first feeding plate and a first conducting wire, the second feeding part includes a second feeding plate and a second conducting wire, a first accommodation hole and a second accommodation hole are disposed on the first radiation patch, the first feeding plate is disposed in the first accommodation hole, the second feeding plate is disposed in the second accommodation hole, the first conducting wire is electrically connected between the first feeding plate and the feed, and the second conducting wire is electrically connected between the second feeding plate and the feed. In this implementation, the first feeding plate and the second feeding plate are disposed at the same layer as the first radiation patch. In this way, only one dielectric layer needs to be disposed between the first radiation patch and the ground layer, and only one dielectric layer needs to be disposed between the second radiation patch and the first radiation patch. This helps reduce an overall size of the millimeter-wave antenna array element. In this architecture, it is equivalent that the millimeter-wave antenna array element provided in this application is disposed on a double-layer PCB, and the double-layer PCB has two dielectric layers (namely, the first dielectric layer and the second dielectric layer) and three metal layers (namely, the ground layer, the first radiation patch, and the second radiation patch). Specifically, the first feeding plate and the second feeding plate may be in any shape such as a circle, a triangle, or a square.
In another implementation, the first feeding plate and the second feeding plate may alternatively be disposed in other locations, for example, embedded in the first dielectric layer. In other words, a metal layer is further disposed inside the first dielectric layer. In this way, it is equivalent that the millimeter-wave antenna array element in this application is disposed on a multi-layer PCB. Certainly, the first feeding plate and the second feeding plate may alternatively be embedded in the second dielectric layer. Alternatively, the first feeding plate and the second feeding plate are respectively disposed inside the first dielectric layer and the second dielectric layer. That is, the first feeding plate and the second feeding plate may be disposed at different layers.
In an implementation, the first conducting wire vertically extends from the first feeding plate to the ground layer, and extends out of the millimeter wave array element from the ground layer, and the second conducting wire vertically extends from the second feeding plate to the ground layer, and extends out of the millimeter wave array element from the ground layer. Lead-out directions of the first conducting wire and the second conducting wire are limited in this implementation. This architecture helps reduce impact of the first feeding part and the second feeding part on antenna radiation performance, reduce a feeding loss, and improve an antenna gain.
The first conducting wire and the second conducting wire may be coaxial cables. An inner conductor of the coaxial cable extends into the first dielectric layer and is electrically connected to the first feeding plate, and an outer conductor of the coaxial cable is electrically connected to the ground layer. Specifically, openings may be disposed at the ground layer and the first dielectric layer, and the openings extend from the ground layer to the first feeding plate. In this way, the first conducting wire and the second conducting wire may extend into the openings and be electrically connected to the first feeding plate and the seconding feeding plate.
In an implementation, the first radiation patch is symmetrically distributed along both a first axis and a second axis, the first axis is perpendicular to the second axis, and the first feeding plate and the second feeding plate are respectively disposed on the first axis and the second axis.
In an implementation, a center of the second radiation patch faces a center of the first radiation patch, and an area of the second radiation patch is less than an area of the first radiation patch. An outline of the first radiation patch is a cross shape, and the outline of the first radiation patch includes four straight line edges located on four sides and four └-shaped edges that are each connected between two adjacent straight line edges and that are located at four corners. An outline of the second radiation patch includes four side edges of a same shape that are located on four sides and that are sequentially connected. Each side edge includes one straight line edge and two L-shaped edges, the two L-shaped edges are bilaterally symmetrical on two sides of the straight line edge, and L-shaped edges of two adjacent side edges are connected. A through hole is disposed in a center area of the second radiation patch. In a specific implementation, the through hole may be but is not limited to a circle. Specific shape structures of the first radiation patch and the second radiation patch are not limited to those described in this implementation, and shapes of the first radiation patch and the second radiation patch may change based on a specific antenna matching requirement.
In an implementation, the millimeter-wave antenna array element further includes one or more resonators, the one or more resonators are distributed on a periphery of the second radiation patch and are insulated from the second radiation patch, and the one or more resonators are configured to improve isolation and a spread bandwidth of the millimeter-wave antenna array element.
In an implementation, there are four resonators, and the resonators are distributed pairwise opposite to each other on four sides of the second radiation patch.
In an implementation, each resonator is in a strip shape, an extension direction of two resonators that are disposed opposite to each other is a first direction, and an extension direction of the other two resonators that are disposed opposite to each other is a second direction. The first direction is perpendicular to the second direction, and in the first direction and the second direction, a size of the second radiation patch is less than or equal to an extension size of each resonator. In other words, a vertical projection of the second radiation patch on the resonator coincides with the resonator or falls within a range of the resonator.
According to a second aspect, this application provides an array antenna, including a plurality of millimeter-wave antenna array elements according to the first aspect. The plurality of millimeter-wave antenna array elements are distributed in an array, all the first dielectric layers are coplanar and jointly form a complete dielectric slab, all the second dielectric layers are coplanar and jointly form a complete dielectric slab, and all the ground layers are coplanar and interconnected as a whole.
In an implementation, the array antenna further includes an isolation structure, the isolation structure is disposed between adjacent millimeter-wave antenna array elements, the isolation structure includes an isolation plate and a plurality of metal through holes, the isolation plate is disposed on a side that is of the second dielectric layers and that is away from the first dielectric layers, the isolation plate is disposed between adjacent second radiation patches, and the plurality of metal through holes extend from the isolation plate to the ground layers.
In an implementation, in a direction perpendicular to the second dielectric layers, a height at which the isolation plate protrudes from the second dielectric layers is greater than a height at which the second radiation patches protrude from the second dielectric layers.
According to a third aspect, this application provides a communications product, including a feed source and the array antenna according to the second aspect, and the feed source is configured to feed electromagnetic wave signals into the first feeding part and the second feeding part.
The following describes the embodiments of this application with reference to accompanying drawings.
A millimeter-wave antenna array element and an array antenna provided in this application are applied to a communications product. The communications product may be a mobile terminal such as a mobile phone operating within a millimeter-wave frequency band range of a 5G communications system. As shown in
Referring to
The millimeter-wave antenna array element 10 further includes a first feeding part 17 and a second feeding part 18. At least a part of the first feeding part 17 is disposed inside the first dielectric layer 13, or inside the second dielectric layer 15, or between the first dielectric layer 13 and the second dielectric layer 15. The first feeding part 17 is insulated from the first radiation patch 14, the second radiation patch 16, and the ground layer 12. At least a part of the second feeding part 18 is disposed inside the first dielectric layer 13, or inside the second dielectric layer 15, or between the first dielectric layer 13 and the second dielectric layer 15. The second feeding part 18 is insulated from the first feeding part 17, the first radiation patch 14, the second radiation patch 16, and the ground layer 12. Specifically, in an implementation, being insulated herein means that features are insulated through isolation of dielectrics, and the dielectrics may be the first dielectric layer 13 and the second dielectric layer 15.
The first feeding part 17 and the second feeding part 18 may be disposed at a same layer, or may be disposed at different layers. The first feeding part 17 and the second feeding part 18 are electrically connected to a feed, to excite electromagnetic wave signals of two frequency bands to each of the first radiation patch 14 and the second radiation patch 16 through spatial coupling, and generate electromagnetic wave signals with two polarizations on each of the first radiation patch 14 and the second radiation patch 16. In other words, electromagnetic wave signals with two polarizations are generated on the first radiation patch 14. Specifically, orthogonally polarized electromagnetic wave signals are generated on the first radiation patch 14, and orthogonally polarized electromagnetic wave signals are also generated on the second radiation patch 16.
For example, the electromagnetic wave signals of the two frequency bands may be electromagnetic wave signals of a frequency band range of 26.5 GHz to 29.5 GHz and electromagnetic wave signals of a frequency band range of 37.0 GHz to 40.5 GHz.
In this application, the first feeding part 17 and the second feeding part 18 are disposed, the first feeding part 17 is spatially coupled to the first radiation patch 14 and the second radiation patch 16, and the second feeding part 18 is spatially coupled to the first radiation patch 14 and the second radiation patch 16, so that electromagnetic wave signals with two different polarizations of a first frequency band are excited on the first radiation patch 14, and electromagnetic wave signals with two different polarizations of a second frequency band are excited on the second radiation patch 16. In this way, the millimeter-wave antenna array element provided in this application can be dual-band and dual-polarized. Specifically, a frequency of an electromagnetic wave signal on the first radiation patch 14 is lower than a frequency of an electromagnetic signal on the second radiation patch 16, that is, the first radiation patch 14 is a low-frequency radiator, and the second radiation patch 16 is a high-frequency radiator.
A thickness of the first dielectric layer 13 is greater than a thickness of the second dielectric layer 15. Herein, the “thickness” is a size in a direction perpendicular to the first dielectric layer 13 and the second dielectric layer 15. In a specific implementation, a vertical distance between the first radiation patch 14 and the ground layer 12 is 0.7 mm, and a vertical distance between the second radiation patch 16 and the ground layer 12 is 0.9 mm.
Specifically, the ground layer 12 is a metal layer formed on a bottom surface of the first dielectric layer 13. The ground layer 12 may be a large-area copper foil layer that covers all the bottom surface of the first dielectric layer 13, or the ground layer 12 may cover only a part of the bottom surface of the first dielectric layer 13. The first radiation patch 14 is a metal layer formed on a top surface of the first dielectric layer 13, the first radiation patch 14 is sandwiched between the first dielectric layer 13 and the second dielectric layer 15, and the second radiation patch 16 is a metal layer formed on a top surface of the second dielectric layer 15.
In an implementation, the first feeding part 17 includes a first feeding plate 171 and a first conducting wire 172, and the second feeding part 18 includes a second feeding plate 181 and a second conducting wire 182. A first accommodation hole 141 and a second accommodation hole 142 are disposed on the first radiation patch 14, the first feeding plate 171 is disposed in the first accommodation hole 141, and the second feeding plate 181 is disposed in the second accommodation hole 142. The first conducting wire 172 is electrically connected between the first feeding plate 171 and the feed, and the second conducting wire 182 is electrically connected between the second feeding plate 181 and the feed. In this implementation, the first feeding plate 171 and the second feeding plate 181 are disposed at the same layer as the first radiation patch 14. In this way, only one dielectric layer needs to be disposed between the first radiation patch 14 and the ground layer 12, and only one dielectric layer needs to be disposed between the second radiation patch 16 and the first radiation patch 14. This helps reduce an overall size of the millimeter-wave antenna array element. In this architecture, it is equivalent that the millimeter-wave antenna array element provided in this application is disposed on a double-layer PCB, and the double-layer PCB has two dielectric layers (namely, the first dielectric layer 13 and the second dielectric layer 15) and three metal layers (namely, the ground layer 12, the first radiation patch 14, and the second radiation patch 16). Specifically, the first feeding plate 171 and the second feeding plate 181 may be in any shape such as a circle, a triangle, or a square.
In another implementation, the first feeding plate 171 and the second feeding plate 181 may alternatively be disposed in other locations, for example, embedded in the first dielectric layer 13. In other words, a metal layer is further disposed inside the first dielectric layer 13. In this way, it is equivalent that the millimeter-wave antenna array element in this application is disposed on a multi-layer PCB. Certainly, the first feeding plate 171 and the second feeding plate 181 may alternatively be embedded in the second dielectric layer 15. Alternatively, the first feeding plate 171 and the second feeding plate 181 are respectively disposed inside the first dielectric layer 13 and the second dielectric layer 15. That is, the first feeding plate 171 and the second feeding plate 181 may be disposed at different layers.
In an implementation, the first conducting wire 172 vertically extends from the first feeding plate 171 to the ground layer 12, and extends out of the millimeter wave array element 10 from the ground layer 12, and the second conducting wire 182 vertically extends from the second feeding plate 181 to the ground layer 12, and extends out of the millimeter wave array element 10 from the ground layer 12. Lead-out directions of the first conducting wire 172 and the second conducting wire 182 are limited in this implementation. This architecture helps reduce impact of the first feeding part 17 and the second feeding part 18 on antenna radiation performance, reduce a feeding loss, and improve an antenna gain.
The first conducting wire 172 and the second conducting wire 182 may be coaxial cables. An inner conductor of the coaxial cable extends into the first dielectric layer 13 and is electrically connected to the first feeding plate 171, and an outer conductor of the coaxial cable is electrically connected to the ground layer 12. Specifically, two openings 11 may be disposed at the ground layer 12 and the first dielectric layer 13. As shown in
The first conducting wire 172 and the second conducting wire 182 may alternatively be probes or other feeding structures.
As shown in
As shown in
In an implementation, a center of the second radiation patch 16 faces a center of the first radiation patch 14, and an area of the second radiation patch 16 is less than an area of the first radiation patch 14. An outline of the first radiation patch 14 is a cross shape, and the outline of the first radiation patch 14 includes four straight line edges 143 located on four sides and four └-shaped edges 144 that are each connected between two adjacent straight line edges 143 and that are located at four corners.
As shown in
Specific shape structures of the first radiation patch 14 and the second radiation patch 16 are not limited to those described in this implementation, and shapes of the first radiation patch 14 and the second radiation patch 16 may change based on a specific antenna matching requirement.
In an implementation, the millimeter-wave antenna array element 10 further includes one or more resonators 19, the one or more resonators 19 are distributed on a periphery of the second radiation patch 16 and are insulated from the second radiation patch 16, and the one or more resonators 19 are configured to improve isolation and a spread bandwidth of the millimeter-wave antenna array element 10.
In an implementation, there are four resonators 19, and the resonators are distributed pairwise opposite to each other on four sides of the second radiation patch 16.
In an implementation, each resonator 19 is in a strip shape, an extension direction of two resonators 19 that are disposed opposite to each other is a first direction, and an extension direction of the other two resonators 19 that are disposed opposite to each other is a second direction. The first direction is perpendicular to the second direction, and in the first direction and the second direction, a size of the second radiation patch 16 is less than or equal to an extension size of each resonator 19. In the first direction and the second direction, a center of the second radiation patch 16 faces a center of the resonator 19. In this way, an orthographic projection of the second radiation patch 16 on any resonator 19 falls within a range of the resonator 19 or coincides with the resonator 19. This architecture herein helps improve isolation between millimeter-wave antenna array elements.
As shown in
An array antenna provided in this application includes a plurality of millimeter-wave antenna array elements distributed in an array. All the first dielectric layers 13 are coplanar and jointly form a complete dielectric slab, all the second dielectric layers 15 are coplanar and jointly form a complete dielectric slab, and all the ground layers 12 are coplanar and interconnected as a whole. In other words, the array antenna includes a first dielectric slab and a second dielectric slab that are stacked, a bottom surface of the first dielectric slab is the ground layers 12, a plurality of first radiation patches 14 arranged in an array are disposed on a top surface of the first dielectric slab, and a plurality of second radiation patches 16 arranged in an array and the resonators 19 arranged around each second radiation patch 16 are disposed on a top surface (to be specific, a surface that is of the second dielectric slab and that is away from the first dielectric slab) of the second dielectric slab. Each second radiation patch 16 is disposed opposite to each first radiation patch 14. The first radiation patch 14, the second radiation patch 16, the resonators 19 around the second radiation patch 16, and a part of the ground layers 12 facing the first radiation patch 14 jointly form a millimeter-wave antenna array element.
As shown in
In an implementation, in a direction perpendicular to the second dielectric layers 15, a height at which the isolation plate protrudes from the second dielectric layers 15 is greater than a height at which the second radiation patches 16 protrude from the second dielectric layers 15. The isolation plate 41 may be a metal plate fastened on the top surface of the second dielectric layers 15, or may be a metal layer formed on the top surface of the second dielectric layers 15 by using a PCB manufacturing process.
The embodiments of this application are described in detail above. The principle and embodiments of this application are described herein through specific examples. The description about the embodiments of this application is merely provided to help understand the method and core ideas of this application. In addition, a person of ordinary skill in the art can make variations and modifications to this application in terms of the specific embodiments and application scopes according to the ideas of this application. Therefore, the content of specification shall not be construed as a limitation on this application.
Filing Document | Filing Date | Country | Kind |
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PCT/CN2018/086197 | 5/9/2018 | WO | 00 |