Air-interface electrically tunable metasurfaces and radiating devices

Abstract

The present application discloses an air-interface electrically tunable metasurface (2), the air-interface electrically tunable metasurface (2) comprising a dielectric substrate and a metal structure array, the dielectric substrate comprising a plurality of dielectric substrate units (200), the metal structure array comprising a plurality of metal structures (100) disposed on the dielectric substrate and corresponding one-to-one to the ±45 degree dual polarized antenna units (11), the metal structures (100) comprising two groups of metal units and a microwave diode (120), each group of metal units comprising two metal pieces (110) distributed axially symmetrically, the two groups of metal units being distributed symmetrically around the center of the ±45 degree dual polarized antenna unit (11), the metal pieces (110) and the microwave diode (120) working together to adjust the phase of the electromagnetic signal polarized at +45 degrees or -45 degrees transmitted from the ±45 degree dual polarized antenna unit (11).

Description

[Technical Field]

[0001] This application is based on and claims priority from a Chinese patent application having application number 202210489719.0 and filing date May 7, 2022, the entire contents of which are incorporated herein by reference.

[0002] This application relates to the technical field of wireless communications, and in particular to air-interface electrically tunable metasurfaces and radiating devices. [Background technology]

[0003] In a base station antenna system, the beam coverage of the antenna is an important reference index for evaluating the system performance, and its characteristics are closely related to indexes such as beam switching and gain coverage. In the current embodiment, the beam switching of the base station antenna is mainly realized by digital electrical adjustment or mechanical electrical adjustment. The digital electrically tunable antenna has a high degree of scheduling freedom, fast response, and small link loss, but the introduction of digital devices in the link increases the overall cost. The mechanically electrically tunable antenna performs beam switching by motor transmission, which has a somewhat low degree of scheduling freedom, slow response, and large link loss. Whether it is a digitally electrically tunable antenna or a mechanically electrically tunable antenna, the beam switching method is realized by the back-end circuit of the antenna array, which results in a relatively complex feeding network for the antenna array and increases the insertion loss of the antenna system. Summary of the Invention [Problem to be solved by the invention]

[0004] The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims.

[0005] Embodiments of the present application provide air-interface electrically tunable metasurfaces and radiating devices. [Means for solving the problem]

[0006] According to a first aspect, an embodiment of the present application provides an air interface electrically adjustable metasurface, the metasurface including a dielectric substrate and a metal structure array, the dielectric substrate including a plurality of dielectric substrate units, the metal structure array being installed on the dielectric substrate unit and including a plurality of metal structures corresponding one-to-one to the ±45 degree dual polarization antenna units, the metal structures including two groups of metal units and a microwave diode, each group of metal units including two metal pieces distributed axially symmetrically, the two groups of metal units being distributed symmetrically around the center of the ±45 degree dual polarization antenna unit, and the metal pieces and the microwave diode working together to adjust the phase of the electromagnetic wave signal polarized at +45 degrees or -45 degrees transmitted from the ±45 degree dual polarization antenna unit.

[0007] According to a second aspect, an embodiment of the present application provides a radiating device, the radiating device including a multi-channel dual-polarized antenna array and an air-interface electrically tunable metasurface described in the first aspect, wherein the multi-channel dual-polarized antenna array includes a plurality of ±45 degree dual-polarized antenna units for transmitting electromagnetic signals, and the air-interface electrically tunable metasurface is installed directly above the radiation direction of the multi-channel dual-polarized antenna array and adjusts the phase of the electromagnetic signals transmitted from the multi-channel dual-polarized antenna array.

[0008] Other features and advantages of the present application will be set forth in the specification which follows, and in part will be obvious from the specification, or may be learned by the practice of the present application. The objectives and other advantages of the present application may be realized and obtained by the structure particularly pointed out in the written description, claims and drawings.

[0009] The drawings are used to provide a further understanding of the technical solutions of the present application, constitute a part of the specification, and are used to interpret the technical solutions of the present application together with the examples of the present application, and do not constitute limitations on the technical solutions of the present application. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic diagram of a beam switching structure of a conventional base station antenna according to the present invention; [Figure 2] 1 is a schematic diagram of an air interface electrically adjustable beam switching structure according to an embodiment of the present application; [Figure 3] 1 is a schematic three-dimensional view of a metal structure in which isosceles trapezoidal metal pieces and diodes are installed on different layers according to an embodiment of the present application; FIG. [Figure 4] FIG. 1 is a plan view of a metal structure in which isosceles trapezoidal metal strips and diodes are located on different layers according to an embodiment of the present application. [Figure 5] 1 is a schematic three-dimensional view of a metal structure in which an isosceles trapezoidal metal piece and a diode are installed on the same layer according to an embodiment of the present application; [Figure 6] FIG. 1 is a plan view of a metal structure in which an isosceles trapezoidal metal strip and a diode are located on the same layer according to one embodiment of the present application. [Figure 7] 1 is a schematic diagram of a metal structure in which a circularly fanned metal piece and a diode are installed on the same layer according to an embodiment of the present application; FIG. [Figure 8] FIG. 1 is a plan view of a metal structure having annular sectored metal strips and a diode disposed on the same layer according to one embodiment of the present application. [Figure 9] 1 is a schematic three-dimensional view of a metal structure in which rectangular metal pieces and diodes are disposed on different layers according to an embodiment of the present application; [Figure 10] FIG. 1 is a plan view of a metal structure with rectangular metal strips and diodes located on different layers according to one embodiment of the present application. [Figure 11] 1 is a schematic diagram illustrating the layout of a multi-channel dual-polarized antenna array according to an embodiment of the present application. [Figure 12]1 is a composite schematic diagram of a multi-channel dual-polarized antenna array unit according to an embodiment of the present application; [Figure 13] FIG. 1 is a schematic diagram of beam deflection of an air-interface electrically tunable metasurface according to one embodiment of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0011] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be described in more detail below with reference to the drawings and examples. The specific examples described herein are only for the purpose of interpreting the present application, and are not intended to limit the present application.

[0012] In the description of this application, the orientations or positional relationships indicated by terms such as "center," "top," and "bottom" are those indicated based on the drawings and are intended merely to facilitate or simplify the description of this application. They do not necessarily indicate or imply that the depicted devices or elements necessarily have a specific orientation or are constructed or operated in a specific orientation, and therefore should not be understood as limiting this application. The terms "first," "second," and "third" are merely descriptive and should not be understood as indicating or implying relative importance. Furthermore, unless otherwise clearly specified or limited, the terms "attached," "coupled," and "connected" should be understood broadly, and may refer to, for example, fixedly connected, detachably connected, integrally connected, mechanically connected, electrically connected, directly connected, indirectly connected via an intermediate medium, or internal communication between two elements. Those skilled in the art will be able to understand the specific meanings of the above terms in this application based on specific circumstances.

[0013] In related art, to achieve beam switching in a channel, beam polarization switching must be achieved in the form of a phase shifter load in each channel. As shown in FIG. 1, in a multi-channel dual-polarized antenna array 1, beam switching requires the use of a number of phase shifters corresponding to the number of antenna units, and the phase distribution between the antenna units is changed by adjusting the phase shifter network in the antenna backend, thereby achieving antenna beam switching. In current embodiments, beam switching in base station antennas is mainly achieved by digital electrical adjustment or mechanical electrical adjustment. However, whether it is a digitally electrically tunable antenna or a mechanically electrically tunable antenna, the beam switching method is achieved by the phase shifter circuit in the backend of the multi-channel dual-polarized antenna array 1, which results in a relatively complex backend feeding network for the multi-channel dual-polarized antenna array 1 and increased insertion loss of the antenna system.

[0014] Beam switching can also be achieved by loading the upper air interface of the antenna with a lens or metamaterial surface, etc. However, current air interface electrically tunable metasurfaces are mainly applied to single-polarized antenna units or linear arrays, which cannot fully meet the beam steering demands of multi-channel dual-polarized antenna arrays 1 in base station systems.

[0015] In order to realize beam switching for each channel, reduce the complexity of the back-end feeding network of the multi-channel dual-polarized antenna array 1 using the conventional electrical tuning method, and reduce the insertion loss of the antenna system, the present application proposes an air-interface electrically tunable metasurface. Referring to Figures 2 to 12, the air-interface electrically tunable metasurface 2 includes a dielectric substrate and a metal structure array, The dielectric substrate includes a plurality of dielectric substrate units 200; The metal structure array includes a plurality of metal structures 100, which are installed on a dielectric substrate unit 200, and the metal structures 100 correspond one-to-one to the ±45 degree dual-polarized antenna units 11, which are installed in the multi-channel dual-polarized antenna array 1, and the metal structures 100 include two groups of metal units and microwave diodes 120, and each group of metal units includes two metal pieces 110 distributed axially symmetrically, and the two groups of metal units are distributed symmetrically around the center of the ±45 degree dual-polarized antenna unit 11, and the metal pieces 110 and the microwave diodes 120 work together to adjust the phase of the electromagnetic signal polarized at +45 degrees or -45 degrees transmitted from the ±45 degree dual-polarized antenna unit 11.

[0016] In addition, the air-interface electrically tunable metasurface 2 of the embodiment of the present application is applied to a multi-channel dual-polarized antenna array 1, which is divided into multiple multi-channel dual-polarized antenna array units 13, each of which includes multiple ±45-degree dual-polarized antenna units 11. Two channels can be separated from one multi-channel dual-polarized antenna array unit 13, and one multi-channel dual-polarized antenna array unit 13 corresponds to one metal structure array unit separated from one metal structure array. In this application, adjacent metal structures 100 refer to two metal structures 100 adjacent to each other in one metal structure array, and the microwave diode 120 may be a varicap diode.

[0017] The air-interface electrically tunable metasurface 2 designed in the embodiment of this application makes the metal structures 100 in the corresponding metal structure array units correspond to the ±45 degree dual-polarized antenna units 11 in the multi-channel dual-polarized antenna array 1. Since the metal structure 100 includes two groups of metal units and microwave diodes 120, each group of metal units including two metal pieces 110 distributed axially symmetrically, and the two groups of metal units distributed symmetrically around the center of the ±45 degree dual polarization antenna unit 11, the embodiment of the present application controls the magnitude of the DC bias voltage applied to both ends of the microwave diode 120 in one metal structure and adjusts the capacitance value of the microwave diode 120, thereby adjusting the phase of the electromagnetic signal polarized at +45 degrees or -45 degrees transmitted from the ±45 degree dual polarization antenna unit 11. Finally, by controlling the electromagnetic signal transmitted from the ±45 degree dual polarization antenna unit 11 corresponding to adjacent metal structures 100 to have a fixed difference between the polarization phase values ​​after passing through the adjacent metal structures 100, beam deflection of the entire multi-channel dual polarization antenna array 1 is realized.

[0018] Since the present embodiment replaces the phase shifter with a corresponding metal structure 100, the present embodiment can be used for multi-channel Dual polarizationThis has the advantages of reducing the complexity of the back-end feeding network of the antenna array 1 and reducing the system insertion loss. The air-interface electrically tunable metasurface 2 designed in the present embodiment can process electromagnetic signals polarized at +45 degrees or -45 degrees, and can also handle situations in which the ±45-degree dual-polarized antenna unit 11 simultaneously transmits electromagnetic signals polarized at +45 degrees and -45 degrees (where the tilt angle of the air-interface electrically tunable metasurface 2 is the same after adjustment for both the +45-degree polarized electromagnetic signal and the -45-degree polarized electromagnetic signal). Therefore, compared to the metal structures of conventional air-interface electrically tunable metasurfaces mainly applied to single-polarized antenna units or linear arrays, the present embodiment can handle the polarization of multi-channel electromagnetic signals, thereby increasing the gain of the multi-channel dual-polarized antenna array 1, improving the product reliability of the multi-channel dual-polarized antenna array 1, and meeting the actual needs of multi-channel dual-polarized antenna arrays in base stations.

[0019] Referring to Figure 2, in order to better receive the electromagnetic wave signals of the multi-channel dual-polarized antenna array 1 and meet the requirements of the air interface, the air interface electrically tunable metasurface 2 in the embodiment of the present application is installed directly above the radiation direction of the multi-channel dual-polarized antenna array 1, and the height from the air interface electrically tunable metasurface 2 to the multi-channel dual-polarized antenna array 1 does not exceed 0.25 wavelengths.

[0020] In order to better adjust the +45 degree polarized electromagnetic signal or -45 degree polarized electromagnetic signal transmitted from the ±45 degree dual polarization antenna unit 11, the shape of the metal pieces 110 of one group of metal units in the metal structure 100 may be an isosceles trapezoid, as shown in Figures 3 and 4, where the upper bases of two adjacent metal pieces 110 of the metal structure 100 are perpendicular to each other, and the upper bases of all the metal pieces 110 of the metal structure 100 form a regular rectangle with four notches, and the upper base is the shorter of the two parallel sides of the isosceles trapezoid. The reason for this arrangement is that when the upper bases of all the metal pieces 110 of the metal structure 100 form a regular rectangle with four notches, the receiving area is larger and the phase of the electromagnetic signal is better adjusted than when the other sides of the isosceles trapezoid form a rectangle.

[0021] In order to better receive the electromagnetic wave signals polarized at +45 degrees or -45 degrees transmitted from the ±45 degree dual polarization antenna unit 11, the shape of the metal pieces 110 of the metal structure 100 may further be annular sector shape, as shown in Figures 7 and 8, where two adjacent metal pieces 110 of the metal structure 100 form a 90 degree angle. A 90 degree angle refers to the angle of 90 degrees between the straight lines respectively identified by the centers of the two adjacent metal pieces 110, i.e., the two adjacent annular sectors, and the center of symmetry. The inner rings of all the metal structures 100 of the metal structure 100 form a circle with four notches, and the center of the circle is the center of symmetry of the four metal pieces 110. Alternatively, considering the area size and cost of the metal pieces 110, the metal pieces 110 of the metal structure 100 may be rectangular, as shown in FIGS. 9 and 10 , where the short sides of all the metal pieces 110 of the metal structure 100 form a regular square with four notches, and the short side is one of the two shortest sides of the metal pieces 110. The reason for using the short side to form a regular square is to better adjust the phase of the electromagnetic wave signal. Note that when the metal pieces 110 of the metal structure 100 shown in FIGS. 9 and 10 are rectangular, the straight line defined by the geometric centers of two pairs of symmetrical metal pieces 110 may be parallel to one of the lower +45-degree and -45-degree polarized antennas, respectively, to ensure that the air-interface electrically tunable metasurface 2 of the embodiment of the present application can adjust the phase of the electromagnetic wave signal transmitted from the multi-channel bipolarized antenna array 1 and thereby realize beam conversion.

[0022] The shape of the metal piece 110 in the embodiment of the present application is not limited to an isosceles trapezoid, a circular sector, and a rectangle, but may be any other reasonable shape, which can be selected by those skilled in the art according to their own needs.

[0023] In order to reduce the cost of the microwave diodes 120 mounted on one metal structure 100, the metal structure 100 shown in Figures 3 and 4 may be used. In the metal structure 100 shown in Figures 3 and 4, the metal structure 100 includes two microwave diodes 120, two groups of metal units are installed on the same plane of the corresponding dielectric substrate unit 200, the two microwave diodes 120 are installed on the upper and lower surfaces of the dielectric substrate unit 200, the two metal pieces 110 of the metal units of each group are connected via one of the microwave diodes 120, the two groups of metal units are connected to the positive and negative poles of a DC bias power supply, and the two microwave diodes 120 are connected in parallel.

[0024] Further referring to the metal structure 100 shown in Figures 3 and 4, in one embodiment of the present application, two metal pieces 110 of one group of metal units are connected through one microwave diode 120 installed on the same plane, and two metal pieces 110 of another group of metal units are each provided with one metal via 130, and one metal via 130 is correspondingly installed with one metal pad 140 on the underside of the dielectric substrate unit 200 and is connected to another microwave diode 120 installed on the underside through two metal pads 140, and the forward current directions of the two microwave diodes 120 are different, and the forward current directions of the two microwave diodes 120 correspond to +45 degree polarization and -45 degree polarization, respectively.

[0025] Although the structure of the metal structure 100 described above can reduce the cost of the microwave diodes 120 per metal structure 100, the wiring must pass from the top to the bottom of the dielectric substrate unit 200, requiring two sets of wiring, resulting in high wiring costs. Therefore, in order to concentrate the wiring of the metal structure 100 on the same plane, the metal structure 100 shown in Figures 5 and 6 may be used. The metal structure 100 includes four microwave diodes 120, two groups of metal units are installed on the same plane of the dielectric substrate unit 200, two adjacent metal pieces 110 are connected via one microwave diode 120, and one group of metal units is used to connect to the positive and negative poles of a DC bias power supply, with the direction of the microwave diodes 120 being the same as the direction of the current in the metal pieces 110. Continuing to refer to Figures 5 and 6, in one embodiment of the present application, the forward current directions of the two microwave diodes 120 connected to the two metal pieces 110 of the metal unit for connecting to the positive and negative poles of the DC bias power supply are different, and as can be seen from observing Figures 5 and 6, the forward current directions of the two microwave diodes 120 connected to the metal piece 110 of the metal unit for connecting to a power supply are one clockwise and one counterclockwise, and the forward current directions of the two microwave diodes 120 connected to the metal piece 110 of the metal unit not connected to a power supply are both clockwise or counterclockwise. In this way, the metal pieces 110 at the lower left corner and the upper right corner of FIG. 6 can be respectively connected to the positive and negative poles of the power supply, so that the two microwave diodes 120 connected to the metal piece 110 at the upper left corner form a series connection relationship, and the two microwave diodes 120 connected to the metal piece 110 at the lower right corner form a series connection relationship, and then these two groups of microwave diodes 120 are connected in parallel, so that the capacitance value of the microwave diodes 120 of one metal structure 100 can be adjusted with just one bias power supply, which saves a lot of wiring costs.

[0026] An embodiment of the present application further provides a radiating device, which comprises a multi-channel dual-polarized antenna array 1 and the air interface Electrically adjustableThe multi-channel dual-polarized antenna array 1 includes a plurality of ±45 degree dual-polarized antenna units 11 for transmitting electromagnetic signals, and the air-interface electrically adjustable metasurface 2 is positioned directly above the radiation direction of the multi-channel dual-polarized antenna array 1 and adjusts the phase of the electromagnetic signals transmitted from the multi-channel dual-polarized antenna array 1.

[0027] In this embodiment, beam switching of the entire multi-channel dual-polarized antenna array 1 is achieved by controlling the ±45 degree dual-polarized antenna units 11 so that there is a fixed difference between the polarization phase values ​​after passing through adjacent metal structures 100. The multi-channel dual-polarized antenna array 1 is divided into a plurality of multi-channel dual-polarized antenna array units 13, and each multi-channel dual-polarized antenna array unit 13 includes a plurality of ±45 degree dual-polarized antenna units 11. The metal structure array of the air interface electrically tunable metasurface in the embodiment of the present application is divided into multiple metal structure array units, each of which includes multiple metal structures 100, each of which corresponds one-to-one to the ±45 degree dual polarization antenna unit 11. Therefore, the electromagnetic signal transmitted from the adjacent ±45 degree dual polarization antenna unit 11 below has a fixed difference after passing through the adjacent metal structure 100. In order to further realize beam deflection, the metal structure 100 may be connected to a DC bias circuit, which is used to adjust the capacitance value of the microwave diode 120 of the metal structure 100. By differentiating the DC bias voltage applied from the DC bias circuit corresponding to the adjacent metal structure 100, the capacitance value of the microwave diode 120 of the adjacent metal structure 100 can be controlled to be different, thereby further realizing beam switching.

[0028] Since the radiating device of the embodiment of the present application applies the above-mentioned air interface electrically tunable metasurface 2, the radiating device of the embodiment of the present application reduces the complexity of the back-end feeding network of the multi-channel dual-polarized antenna array 1, reduces the system insertion loss, increases the gain of the multi-channel dual-polarized antenna array 1, improves the product reliability of the multi-channel dual-polarized antenna array 1, and can meet the actual demands of the multi-channel dual-polarized antenna array 1 in base stations, providing competitive advantages in antenna products and a good user experience.

[0029] In the radiating device according to the embodiment of the present application, the ±45 degree dual polarized antenna unit 11 is It may be one of the following dual polarized antennas: a half-wave symmetrical transducer, a microstrip patch antenna, a magnetoelectric dipole antenna, or a dielectric resonator antenna.

[0030] Below, we explain the air-interface electrically tunable metasurface of the present application through practical examples.

[0031] The multi-channel dual polarized antenna array 1 includes a plurality of multi-channel dual polarized antenna array units, an antenna dielectric substrate, and a metal base, as shown in FIG. 11. Referring to FIG. 11, 11 denotes a ±45-degree dual polarized antenna unit, 12 denotes the antenna dielectric substrate, and 13 denotes the multi-channel dual polarized antenna array unit. In the figure, the multi-channel dual polarized antenna array unit 13 and the metal base (not shown in FIG. 11) are located on either side of the antenna dielectric substrate 12, respectively. The multi-channel dual polarized antenna array 1 comprises 96 ±45-degree dual polarized antenna units 11 arranged in a plane along the x-axis and y-axis. The ±45-degree dual polarized antenna units 11 are spaced approximately 0.67 wavelengths apart along the x-axis and approximately 0.46 wavelengths apart along the y-axis. Every sixth ±45-degree dual polarized antenna unit 11 is connected and combined with the multi-channel dual polarized antenna array unit 13 via a power divider, as shown in FIG. 12. The two power dividers each connect and combine the two polarizations of six ±45 degree dual polarized antenna units 11 along the x-axis, and the multi-channel dual polarized antenna array unit 13 combines two channels per column, so that the multi-channel dual polarized antenna array 1 has a total of 32 channels.

[0032] To achieve beam switching for each channel and reduce the complexity of the antenna backend power network required by conventional electrical tuning methods, a metasurface is used to electrically tune the beam at the air interface, as shown in Figures 2 to 12. The air-interface electrically tunable metasurface 2 has a phase control function and its tuning range covers the operating frequency of the antenna. It includes a dielectric substrate and a metal structure array, where the dielectric substrate includes multiple dielectric substrate units 200 and the metal structure array includes multiple metal structures 100. The metal structures 100 are installed on the dielectric substrate unit 200, and the metal structures 100 correspond one-to-one to the ±45-degree bipolarized antenna units 11. The ±45-degree bipolarized antenna units 11 are installed in the multi-channel bipolarized antenna array 1. The metal structure 100 includes two groups of metal units and microwave diodes 120, each group of metal units including two metal pieces 110, and the two groups of metal units are distributed symmetrically around the center of the ±45-degree bipolarized antenna units 11. As shown in FIGS. 3 and 4, the shape of the metal piece 110 is an isosceles trapezoid, the upper base of the metal piece 110 of the metal structure is vertical, the upper base of the metal piece 110 of the metal structure forms a regular rectangle with four notches, the metal structure includes two microwave diodes 120, two groups of metal units are installed on the same plane of the corresponding dielectric substrate unit 200, the two metal pieces 110 of one group of metal units are connected through one microwave diode 120 installed on the same plane, and one metal via 130 is provided in each of the two metal pieces 110 of the other group of metal units, and one metal The metal via 130 is correspondingly installed with one metal pad 140 on another plane of the dielectric substrate unit 200, and the two metal pads 140 are connected through another microwave diode 120 installed on the same plane, and the forward current directions of the two microwave diodes 120 are different, and the forward current directions of the two microwave diodes 120 correspond to +45 degree polarization and -45 degree polarization respectively, so that the metal piece 110 and the microwave diode 120 can cooperate to adjust the phase of the electromagnetic wave signal polarized at +45 degrees or -45 degrees polarized atFurthermore, by adjusting the DC power supply bias value of every two corresponding microwave diodes 120, the single-row beams can be transmitted through the adjacent periodic metal structures 100 with a certain phase difference, further realizing the air interface beam electrical adjustment characteristics of the multi-channel dual-polarized antenna array 1.

[0033] Using the air interface beam electrical tuning technology, a phase-tunable periodic structure with bipolarization characteristics is used to design a metasurface required for air interface electrical tuning. The principle of the air interface beam in this embodiment is as follows: As shown in Figure 13, in the beam propagation path, by adjusting the DC power supply bias value of every two corresponding microwave diodes 120 in the designed air interface electrically tunable metasurface 2, the phase φ1 to φ2 of the incident plane wave passing through the metasurface can be adjusted. n In this example, the electromagnetic wave signal transmitted from the ±45-degree dual polarization antenna unit 11 initially has an initial phase value. Then, by changing the bias DC voltage, the capacitance values ​​of the two corresponding microwave diodes 120 in the metal structure corresponding to the ±45-degree dual polarization antenna unit 11 in the air-interface electrically tunable metasurface are controlled to change the phase value of the electromagnetic wave signal transmitted from the ±45-degree dual polarization antenna unit 11 from the initial phase value to a polarized phase value. For example, the phase value of the electromagnetic wave signal transmitted from the first ±45-degree dual polarization antenna unit 11 is changed from the initial phase value to φ1, the phase value of the electromagnetic wave signal transmitted from the second ±45-degree dual polarization antenna unit 11 is changed from the initial phase value to φ2, the phase value of the electromagnetic wave signal transmitted from the third ±45-degree dual polarization antenna unit 11 is changed from the initial phase value to φ3, and so on, where φ2 - φ1 = φ3 - φ2 = ... φ n -φ n-1By controlling the formation of a specific phase difference between adjacent periodic metallic structures 100 and adjusting the local phase of the incident plane wave, the equiphase surface of the radiation field is deflected after passing through the air-interface electrically tunable metasurface 2, which further controls the radiation direction of the entire antenna at the air interface, thereby realizing beam deflection switching.

[0034] The air-interface electrically tunable metasurface 2 replaces the traditional mechanical and electrical tuning structure, and controls the transmission phase of the periodic metallic structure 100 of the air-interface electrically tunable metasurface by external voltage, thereby realizing antenna beam switching. Compared with traditional electrical tuning methods, the air-interface electrically tunable metasurface 2 can effectively reduce the complexity of the antenna backend feeding network, reduce the system insertion loss, increase the antenna gain, and improve the reliability of antenna products.

[0035] The form of the periodic metal structure 100 of the air-interface electrically tunable metasurface 2 is not limited to the form of the above metal structure 100, and may be other metal structures 100 having ±45 degree dual polarization characteristics. The air-interface electrically tunable metasurface 2 in this example is located above the multi-channel dual-polarized antenna array 1, and the height to the surface of the multi-channel dual-polarized antenna array 1 does not exceed 0.25 wavelengths.

[0036] The number of periodic metal structures 100 of the air interface electrically adjustable metasurface in this example is determined by the antenna array surface, and the air interface electrically adjustable metasurface 2 only needs to cover the emission range of the antenna array surface.

[0037] Regarding the selection of the microwave diode 120 in this example, the required phase difference can be determined based on the antenna frequency, the required maximum deflection angle of the radiation field, and the size of the periodic metallic structure 100 of the air interface electrically tunable metasurface 2, and finally, a microwave diode 120 that can meet the requirements within the operating frequency based on the range can be searched for.

[0038] The air-interface electrically tunable metasurface according to the embodiments of the present application has at least the following beneficial effects:

[0039] The air-interface electrically tunable metasurface of the present application has metal structures that correspond one-to-one to the ±45-degree dual-polarized antenna units of the multi-channel dual-polarized antenna array. The metal structures include two groups of metal units and microwave diodes, each of which includes two metal pieces, and the two groups of metal units are symmetrically distributed around the center of the ±45-degree dual-polarized antenna unit. Therefore, the present application can adjust the phase of the +45-degree polarized or -45-degree polarized electromagnetic signal transmitted from the ±45-degree dual-polarized antenna unit by controlling the magnitude of the DC bias voltage applied to the positive and negative poles of the microwave diode in one metal structure. Finally, by controlling the polarization phase values ​​of adjacent metal structures to have a fixed difference, the polarization switching of the beam of the entire multi-channel dual-polarized antenna array is realized. Therefore, the embodiments of the present application can reduce the complexity of the back-end feeding network of the multi-channel ±45-degree dual polarized antenna array, reduce the system insertion loss, increase the gain of the multi-channel ±45-degree dual polarized antenna array, improve the product reliability of the multi-channel ±45-degree dual polarized antenna array, and meet the actual demands of the multi-channel ±45-degree dual polarized antenna array in base stations.

[0040] Although several examples of the present application have been specifically described above, the present application is not limited to the above-described embodiments, and those skilled in the art may make various equivalent modifications and substitutions without departing from the scope of the present application, and all of these equivalent modifications and substitutions are included in the scope limited by the claims of the present application. [Explanation of symbols]

[0041] 1. Multi-channel dual-polarized antenna array 2. Air-interface electrically tunable metasurfaces 11 ±45 degree dual polarized antenna unit 12 Antenna dielectric substrate 13 Multi-channel dual-polarized antenna array unit 100 metal construction 110 Metal piece 120 Microwave Diode 130 Metal Vias 140 Metal Pad 200 Dielectric substrate unit

Claims

1. An air-interface electrically tunable metasurface, comprising: a dielectric substrate; and a metal structure array; the dielectric substrate includes a plurality of dielectric substrate units; the metal structure array is disposed on the dielectric substrate unit and includes a plurality of metal structures corresponding one-to-one to the ±45 degree dual polarized antenna units, the metal structures include two groups of metal units and microwave diodes, each group of metal units includes two metal pieces distributed axially symmetrically, the two groups of metal units are distributed symmetrically around the center of the ±45 degree dual polarized antenna unit, and the metal pieces and the microwave diodes cooperate to adjust the phase of the electromagnetic wave signal polarized at +45 degrees or -45 degrees transmitted from the ±45 degree dual polarized antenna unit; The shape of the metal piece is an isosceles trapezoid, and the upper bases of two adjacent metal pieces of the metal structure are perpendicular to each other; or The metal pieces are shaped like an annular sector, and two adjacent metal pieces of the metal structure form a 90-degree angle; or The metal pieces are rectangular in shape, and the short sides of two adjacent metal pieces of the metal structure are perpendicular to each other. Air-interface electrically tunable metasurfaces.

2. The metal structure includes four microwave diodes, two groups of the metal units are installed on the same plane of the dielectric substrate unit, two adjacent metal pieces are connected via one microwave diode, one group of the metal units is used to connect to the positive and negative poles of a DC bias power supply, and the direction of the microwave diode is the same as the direction of the current in the metal pieces. The air-interface electrically tunable metasurface of claim 1.

3. The metal structure includes two microwave diodes, and two groups of metal units are installed on the same plane of the dielectric substrate unit, and the two microwave diodes are installed on the upper and lower surfaces of the dielectric substrate unit, respectively. The two metal pieces of the metal units of each group are connected via one of the microwave diodes, and the two groups of metal units are connected to the positive and negative poles of a DC bias power supply, respectively. The air-interface electrically tunable metasurface of claim 1.

4. The metal structure further includes a metal via and a metal pad, and the two metal pieces of one group of the metal units are connected to the microwave diode through the metal pad and the metal via. The air-interface electrically tunable metasurface of claim 3.

5. The air-interface electrically tunable metasurface is placed directly above the radiation direction of the multi-channel dual-polarized antenna array, and the height from the air-interface electrically tunable metasurface to the multi-channel dual-polarized antenna array does not exceed 0.25 wavelengths; The air-interface electrically tunable metasurface of claim 1.

6. A radiating device comprising: a multi-channel dual-polarized antenna array; and an air-interface electrically tunable metasurface according to any one of claims 1 to 5, wherein the multi-channel dual-polarized antenna array comprises a plurality of ±45 degree dual-polarized antenna units for transmitting electromagnetic signals, and the air-interface electrically tunable metasurface is installed directly above the radiation direction of the multi-channel dual-polarized antenna array and adjusts the phase of the electromagnetic signals transmitted from the multi-channel dual-polarized antenna array.

7. 7. The radiating device of claim 6, wherein the multi-channel dual-polarized antenna array is divided into a plurality of multi-channel dual-polarized antenna array units, and the multi-channel dual-polarized antenna array unit includes a plurality of the ±45 degree dual-polarized antenna units; the metal structure array of the air-interface electrically tunable metasurface is divided into a plurality of metal structure array units, and the metal structure array unit includes a plurality of the metal structures, and the multi-channel dual-polarized antenna array units correspond one-to-one to the metal structure arrays, and the metal structures are connected to a DC bias circuit, and the DC bias circuit is used to adjust the capacitance value of the microwave diode of the metal structure.

8. The ±45 degree dual polarized antenna unit is It is one of the ±45 degree dual polarized antennas, such as half-wave symmetrical oscillator, microstrip patch antenna, magnetoelectric dipole antenna, and dielectric resonator antenna. The radiation device of claim 6.

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