Reflector antenna, beam control method, and communication device

Abstract

An embodiment of the present application provides a reflector antenna, a beam control method, and a communication device. The antenna includes a main reflector panel and a feed structure. The feed structure includes a feed source and a sub-reflector panel. The distance and relative posture between the feed source and the sub-reflector panel are fixed. The main reflector panel is a spherical panel. The feed structure is used to rotate relative to the main reflector panel around the center of the sphere where the main reflector panel is located. The first surface of the sub-reflector panel is provided with a metasurface array. The feed source is used to generate electromagnetic waves, and the sub-reflector panel is used to perform phase control on the electromagnetic waves generated by the feed source through the first surface, and to send the phase-controlled electromagnetic waves to the main reflector panel through the first surface. The main reflector panel is used to reflect the phase-controlled electromagnetic waves. The present application uses a metasurface array to phase control electromagnetic waves, thereby realizing a spherical reflector antenna with a simple system and high antenna gain.

Description

Technical Field

[0001] The present application relates to the field of antenna technology, and in particular to a reflector antenna, a beam control method, and a communication device. Background Art

[0002] Microwave antennas include end-fire antennas, slot antennas, and reflector antennas. Reflector antennas are widely used due to their high gain. Reflector antennas can be categorized into single-reflector antennas and multi-reflector antennas based on the number of reflectors. Single-reflector antennas consist of a feed and a reflector, while multi-reflector antennas consist of a feed, a primary reflector, and at least one secondary reflector. Reflector antennas can be categorized into rotating parabolic antennas, spherical reflector antennas, and cylindrical parabolic antennas based on the shape of the reflector. The spherical reflector of a spherical reflector antenna is isotropically symmetrical. When the feed rotates about the center of the sphere, the direction of the beam's emission also rotates, but the antenna's gain remains unchanged, making it suitable for beam scanning and tracking.

[0003] In the prior art, if a spherical reflector antenna uses a spherical main reflector and a sub-reflector, it will not be able to simultaneously meet the law of conservation of energy and the law of equal optical path length, which will affect the antenna gain of the spherical reflector antenna. If a spherical reflector antenna uses a spherical main reflector antenna and multiple sub-reflector antennas (such as two sub-reflectors), the spherical reflector antenna can simultaneously meet Snell's law of reflection, the law of conservation of energy, and the law of equal optical path length, ensuring a higher antenna gain. However, the multiple sub-reflectors make the antenna system more complex. Summary of the Invention

[0004] The embodiments of the present application provide a reflector antenna, a beam control method, and a communication device. The present application can control the phase of electromagnetic waves through a metasurface array to realize a spherical reflector antenna with a simple system and high antenna gain.

[0005] In a first aspect, embodiments of the present application provide a reflector antenna comprising a primary reflector panel and a feed structure. The feed structure comprises a feed source and a secondary reflector panel, wherein the feed source and the secondary reflector panel are fixed in distance and relative orientation. The primary reflector panel is spherical, and the feed structure is configured to rotate relative to the primary reflector panel about the center of the sphere on which the primary reflector panel resides. The secondary reflector panel has a metasurface array disposed on its first surface.

[0006] The feed source is used to generate electromagnetic waves. The secondary reflector panel is used to phase-control the electromagnetic waves generated by the feed source through the first surface, and transmit the phase-controlled electromagnetic waves to the primary reflector panel through the first surface. The primary reflector panel is used to reflect the phase-controlled electromagnetic waves.

[0007] In this reflector antenna, the sub-reflector panel realizes phase control of the electromagnetic waves to be emitted through the first surface covered with a metasurface array, so that the reflector antenna can simultaneously satisfy Snell's reflection law, the law of conservation of energy and the law of equal optical path length, reducing the system complexity caused by the use of multiple sub-reflector panels, while ensuring that the reflector antenna has a better system gain.

[0008] In combination with the first aspect, in an alternative implementation, the relative position of the main reflection panel and the center of the spherical surface where the main reflection panel is located remains unchanged, and the feed structure is used to rotate around the center of the spherical surface where the main reflection panel is located.

[0009] In combination with the first aspect, in an alternative implementation, the relative position of the feed structure and the center of the sphere where the main reflection panel is located remains unchanged, and the main reflection panel is used to rotate around the center of the sphere where the main reflection panel is located.

[0010] In conjunction with the first aspect, in an alternative implementation, the first surface is a plane on the secondary reflective panel. In another alternative implementation, the first surface may also be a curved surface on the secondary reflective panel.

[0011] The metasurface array arranged on the first surface of the secondary reflective panel can be realized by a metal structure or a liquid crystal array.

[0012] If the metasurface array disposed on the first surface of the secondary reflector panel is implemented using a metal structure, in combination with the first aspect, in an alternative implementation, the metasurface array on the first surface includes a phase control layer, a dielectric layer, and a reflective layer, the phase control layer includes multiple metasurface units uniformly arranged on the dielectric layer, each metasurface unit includes a metal structure, and the reflective layer is used to reflect electromagnetic waves passing through the phase control layer and the dielectric layer. Furthermore, the structural shapes of the metal structures of different metasurface units in the multiple metasurface units are not exactly the same. That is, the structural shapes of the metal structures of each metasurface unit in the multiple metasurface units can be different, or some of them can have the same structural shapes.

[0013] If the metasurface array arranged on the first surface of the secondary reflective panel is implemented by a liquid crystal array, in combination with the first aspect, in an alternative implementation, the metasurface array on the first surface includes a plurality of uniformly arranged metasurface units, each metasurface unit includes a lattice, and the lattice contains liquid crystal. The liquid crystal in the lattice is used to perform phase control on the electromagnetic wave generated by the feed source by applying a bias voltage, and to transmit the electromagnetic wave after phase control. Furthermore, the bias voltages applied to the liquid crystals in different lattices among the multiple lattices are not exactly the same, that is, the bias voltages applied to the liquid crystals in each lattice among the multiple lattices may be different, or the bias voltages applied to the liquid crystals in some lattices may be the same.

[0014] In conjunction with the first aspect, in an alternative implementation, the two metasurface units in the first surface have different phase control capabilities for electromagnetic waves of the same wavelength. The phase control capability of the metasurface unit for electromagnetic waves is determined based on the distance between the metasurface unit and the feed source, the distance between the metasurface unit and the reflection position of the main reflection surface corresponding to the metasurface unit, and the distance between the reflection position of the main reflection surface corresponding to the metasurface unit and the aperture of the reflection surface antenna. The reflection position of the main reflection surface corresponding to the metasurface unit is the position where the electromagnetic wave emitted from the feed source reaches the main reflection panel after being reflected by the metasurface unit.

[0015] In conjunction with the first aspect, in an alternative implementation, the metasurface array of the first surface includes a first metasurface unit and a second metasurface unit; the secondary reflective panel is specifically configured to perform phase compensation of a first phase difference on the electromagnetic wave through the first metasurface unit, and to perform phase compensation of a second phase difference on the electromagnetic wave through the second metasurface unit. The first phase difference and the second phase difference satisfy the following formula:

[0016]

[0017] in, is the first phase difference, l1 is the distance from the first metasurface unit to the feed source, l2 is the distance from the first metasurface unit to the reflection position of the main reflection surface corresponding to the first metasurface unit, l3 is the distance from the reflection position of the main reflection surface corresponding to the first metasurface unit to the aperture of the reflection surface antenna, λ is the wavelength of the electromagnetic wave, is the second phase difference, l4 is the distance from the second metasurface unit to the feed source, l5 is the distance from the second metasurface unit to the reflection position of the main reflection surface corresponding to the second metasurface unit, and l6 is the distance from the reflection position of the main reflection surface corresponding to the second metasurface unit to the aperture of the reflection surface antenna.

[0018] The second aspect of an embodiment of the present application provides another reflecting surface antenna, which includes a main reflecting panel and a receiving structure, the receiving structure includes a receiver and a sub-reflecting panel, and the distance and relative posture between the receiver and the sub-reflecting panel are fixed; the main reflecting panel is a spherical panel; the receiving structure is used to rotate relative to the main reflecting panel around the center of the sphere where the main reflecting panel is located; the second surface of the sub-reflecting panel is provided with a metasurface array.

[0019] Among them, the main reflecting panel is used to receive electromagnetic waves and reflect the received electromagnetic waves; the sub-reflecting panel is used to phase-control the electromagnetic waves reflected from the main reflecting panel to the main reflecting panel through the second surface, and to send the phase-controlled electromagnetic waves to the receiver through the second surface; the receiver is used to receive and process the electromagnetic waves sent by the sub-reflecting panel.

[0020] In this reflector antenna, the sub-reflector panel realizes phase control of the received electromagnetic waves through the second surface equipped with a metasurface array, so that the reflector antenna can simultaneously satisfy Snell's reflection law, the law of conservation of energy and the law of equal optical path length, reducing the system complexity caused by the use of multiple sub-reflector panels while ensuring that the reflector antenna has a better system gain.

[0021] In combination with the second aspect, in an alternative implementation, the relative position of the main reflective panel and the center of the spherical surface where the main reflective panel is located remains unchanged, and the receiving structure is used to rotate around the center of the spherical surface where the main reflective panel is located.

[0022] In combination with the second aspect, in an alternative implementation, the relative position of the receiving structure and the center of the spherical surface where the main reflection panel is located remains unchanged, and the main reflection panel is used to rotate around the center of the spherical surface where the main reflection panel is located.

[0023] In conjunction with the second aspect, in an alternative implementation, the second surface is a plane on the secondary reflective panel. In another alternative implementation, the second surface is a curved surface on the secondary reflective panel.

[0024] In conjunction with the second aspect, in an alternative implementation, the metasurface array on the second surface includes a phase control layer, a dielectric layer, and a reflective layer; the phase control layer includes multiple metasurface units evenly arranged on the dielectric layer, each metasurface unit including a metal structure; and the reflective layer is used to reflect electromagnetic waves that pass through the phase control layer and the dielectric layer. Furthermore, the structural shapes of the metal structures of different metasurface units within the multiple metasurface units are not completely identical. In other words, the structural shapes of the metal structures of each metasurface unit within the multiple metasurface units can be completely different, or some of the metal structures can be partially identical.

[0025] In conjunction with the second aspect, in an alternative implementation, the metasurface array of the second surface includes a plurality of uniformly arranged metasurface units, each metasurface unit including a lattice containing liquid crystal. The liquid crystal in the lattice is used to phase-control the electromagnetic wave generated by the feed source by applying a bias voltage, and to transmit the electromagnetic wave after phase control. Furthermore, the bias voltages applied to the liquid crystals in different lattices among the multiple lattices are not exactly the same, that is, the bias voltages applied to the liquid crystals in each lattice among the multiple lattices may be different, or the bias voltages applied to the liquid crystals in some lattices may be the same.

[0026] In conjunction with the second aspect, in an alternative implementation, different metasurface units in the second surface have different phase control capabilities for electromagnetic waves of the same wavelength. The phase control capability of the metasurface unit for electromagnetic waves is determined based on the distance between the metasurface unit and the receiver, the distance between the metasurface unit and the reflection position of the main reflection surface corresponding to the metasurface unit, and the distance between the reflection position of the main reflection surface corresponding to the metasurface unit and the aperture of the reflection surface antenna. The reflection position of the main reflection surface corresponding to the metasurface unit is the reflection position of the electromagnetic wave reaching the metasurface unit on the main reflection panel.

[0027] In conjunction with the second aspect, in an alternative implementation, the metasurface array of the second surface includes a first metasurface unit and a second metasurface unit; the secondary reflective panel is specifically configured to perform phase compensation of a first phase difference on the electromagnetic wave through the first metasurface unit, and to perform phase compensation of a second phase difference on the electromagnetic wave through the second metasurface unit. The first phase difference and the second phase difference satisfy the following formula:

[0028]

[0029] in, is the first phase difference, l1 is the distance from the first metasurface unit to the receiver, l2 is the distance from the first metasurface unit to the reflection position of the main reflection surface corresponding to the first metasurface unit, l3 is the distance from the reflection position of the main reflection surface corresponding to the first metasurface unit to the aperture of the reflection surface antenna, λ is the wavelength of the electromagnetic wave, is the second phase difference, l4 is the distance from the second metasurface unit to the receiver, l5 is the distance from the second metasurface unit to the reflection position of the main reflection surface corresponding to the second metasurface unit, and l6 is the distance from the reflection position of the main reflection surface corresponding to the second metasurface unit to the aperture of the reflection surface antenna.

[0030] A third aspect of the present application provides a beam steering method for a reflector antenna. The method is applied to a reflector antenna comprising a primary reflector panel and a feed structure, wherein the feed structure comprises a feed source and a secondary reflector panel, and the feed source and the secondary reflector panel are fixed in distance and relative orientation. The primary reflector panel is a spherical panel; the feed structure is configured to rotate relative to the primary reflector panel about the center of the sphere on which the primary reflector panel resides; and a metasurface array is disposed on a first surface of the secondary reflector panel.

[0031] In this method, electromagnetic waves are generated at a feed source. These waves are transmitted to a first surface of a secondary reflector panel, where they are phase-controlled. The phase-controlled electromagnetic waves are then transmitted to a primary reflector panel, where they are reflected.

[0032] A fourth aspect of the present application provides another beam steering method, applied to a reflector antenna. The reflector antenna includes a primary reflector panel and a receiving structure, the receiving structure including a receiver and a secondary reflector panel, the receiver and secondary reflector panel being fixed relative to each other. The primary reflector panel is a spherical panel; the receiving structure is configured to rotate relative to the primary reflector panel about the center of the sphere on which the primary reflector panel resides; and a metasurface array is disposed on the second surface of the secondary reflector panel.

[0033] In this method, electromagnetic waves transmitted to a primary reflective panel are received and reflected by the primary reflective panel. Phase control of the electromagnetic waves reflected by the primary reflective panel is performed using a second surface. The phase-controlled electromagnetic waves are then transmitted to a receiver, which receives and processes the phase-controlled electromagnetic waves.

[0034] The fifth aspect of the embodiments of the present application provides a communication device, which includes the reflective surface antenna provided by the first aspect of the embodiments of the present application or any one of its alternative implementations, and / or includes the reflective surface antenna provided by the second aspect of the embodiments of the present application or any one of its alternative implementations.

[0035] A sixth aspect of the present application provides a communication system, comprising at least one transmitting device and at least one receiving device, wherein the transmitting device is configured to transmit electromagnetic waves and the receiving device is configured to receive electromagnetic waves. The transmitting device may include the reflector antenna provided in the first aspect of the present application or any alternative implementation thereof, and / or the receiving device may include the reflector antenna provided in the second aspect of the present application or any alternative implementation thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0037] Figure 1 An example diagram of a reflector antenna provided in an embodiment of the present application;

[0038] Figure 2 This is a schematic diagram of a dual-reflector antenna configuration provided by an embodiment of the present application;

[0039] Figure 3 Schematic diagram of a metasurface unit provided in an embodiment of the present application;

[0040] Figure 4 A schematic diagram of another metasurface unit provided in an embodiment of the present application;

[0041] Figure 5 Schematic diagram of the metasurface metal structure provided in the embodiment of the present application;

[0042] Figure 6 An example diagram of a metasurface unit provided in an embodiment of the present application;

[0043] Figure 7 This is a schematic structural diagram of a reflector antenna provided in an embodiment of the present application;

[0044] Figure 8 A schematic plan view of a secondary reflective panel provided in an embodiment of the present application;

[0045] Figure 9 A schematic diagram of a reflector antenna provided in an embodiment of the present application;

[0046] Figure 10 This is a schematic structural diagram of a reflector antenna provided in an embodiment of the present application;

[0047] Figure 11 It is a schematic diagram of a communication system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0049] An embodiment of the present application provides a reflector antenna. Before introducing the reflector antenna provided by the embodiment of the present application, the basic structure, relevant parameters and design method of the reflector antenna are briefly introduced.

[0050] See Figure 1 , Figure 1 This is an example diagram of a reflector antenna provided in an embodiment of the present application. Figure 1 Take this as an example to introduce: Figure 1(1a) shows a single reflector antenna, and (1b) shows a dual reflector antenna. The single reflector antenna shown in (1a) includes a bracket, a feed source, and a reflector. The bracket can be used to support the feed source and the reflector. The feed source can be used to generate electromagnetic waves, and the reflector can be used to reflect the electromagnetic waves generated by the feed source. The dual reflector antenna shown in (1b) includes a bracket, a feed source, a main reflector, and a sub-reflector. The bracket can be used to support the feed source, the sub-reflector, and the main reflector. The feed source can be used to generate electromagnetic waves, and the sub-reflector can be used to reflect the electromagnetic waves generated by the feed source to the main reflector. The main reflector can further reflect the electromagnetic waves reflected by the sub-reflector.

[0051] Antenna gain and antenna efficiency are parameters used to describe an antenna's electromagnetic wave transmission performance. Antenna gain is the ratio of the signal power density generated by an actual antenna to that generated by an ideal radiating element at the same point in space, given equal input power. It can be used to quantitatively describe the degree to which an antenna concentrates its input power. Antenna efficiency is the ratio of an antenna's radiated power to its input power.

[0052] From the perspective of electromagnetic waves emitted by an antenna, if the antenna's reflective surface emits the electromagnetic waves in a parallel direction, then because the direction of the emitted electromagnetic waves is relatively concentrated, the power density of the electromagnetic waves and the received radiation power at a certain point in space will be relatively large. In other words, the antenna gain and antenna efficiency of an antenna that emits electromagnetic waves in a parallel direction will be large. On the other hand, if the direction of the electromagnetic waves emitted by the antenna's reflective surface is relatively stray, the power of the electromagnetic waves is relatively dispersed, and the power density of the electromagnetic waves and the received radiation power at that point in space will also be relatively small. In other words, the antenna gain and antenna efficiency of an antenna that emits electromagnetic waves in a parallel direction will be small.

[0053] Antenna aperture is a parameter that indicates the efficiency of the antenna in receiving radio waves. It refers to the area perpendicular to the direction of the incident electromagnetic wave and effectively intercepts the energy of the incident electromagnetic wave. For example, Figure 1 In the single reflector antenna shown in (1a), the antenna aperture can be a circle formed by the edge of the reflector.

[0054] During the design process of a reflector antenna, a reflector with a known, fixed shape can be directly used. For example, a parabolic antenna can have a reflector formed by rotating a parabola 360° around its vertex. However, when using existing reflectors with known, fixed shapes, the reflector antenna may experience defocusing during use. That is, the electromagnetic waves emitted in some emission directions may be stray electromagnetic waves, affecting the antenna gain and efficiency of the reflector antenna. Therefore, during the design process of a reflector antenna, a reflector with a known, fixed shape can be used instead. Instead, the reflector antenna's reflector (for multi-reflector antennas, this can include the main reflector and / or sub-reflector) can be shaped using antenna shaping technology.

[0055] When shaping a reflector antenna, the functional relationship satisfied by the reflector that maximizes antenna gain and efficiency can be determined based on three constraints, thereby completing the shaping of the reflector. These three constraints are Snell's law of reflection, the law of conservation of energy, and the law of equal optical path length. Taking the shaping of the main and secondary reflectors of a dual-reflector antenna as an example, these three constraints are briefly introduced:

[0056] (1) Snell's law of reflection: When an electromagnetic wave propagates to a secondary reflector or a primary reflector, reflection and refraction will occur, where the incident angle and the reflection angle are equal.

[0057] (2) Law of conservation of energy: The energy of the electromagnetic wave received within a certain range on the secondary reflector is equal to the energy of the electromagnetic wave received within the same range after being reflected to the primary reflector.

[0058] (3) Law of equal optical path: The distance that the electromagnetic wave generated from the phase center of the feed source travels after being reflected by the secondary reflector and the main reflector and then reaches the aperture of the main reflector is a constant value.

[0059] The specific shaping process is Figure 2 For example, see Figure 2 , Figure 2 This is a schematic diagram of a dual-reflector antenna shaping provided by an embodiment of the present application. The points of the main reflector are represented by orthogonal coordinates, and the points of the secondary reflector are represented by coordinates of a spherical coordinate system. The shaping process in the ZOX plane is introduced as an example. That is, let y = 0 in the coordinates of each point in the main reflector, and let y = 0 in the coordinates of each point in the secondary reflector. Assume that the coordinates of the center point of the main reflector are (x0, z0), and for any point (x, z) on the main reflector, the maximum value of x is x max , the coordinates of the center point of the sub-reflector are (ρ0, θ0), and for any point (ρ, θ) on the sub-reflector, the maximum value of θ is θ max In addition, p(x) is the aperture field distribution function specified for the antenna, f(θ) is the radiation pattern of the antenna feed, (x0, z0), x max , (ρ0, θ0), θ max , p(x), and f(θ) are all known parameters.

[0060] In the specific shaping: the first step is to initialize and set θ from θ0 to θ max The step length is dθ.

[0061] The second step is Figure 2As shown in the figure, the angle dθ between the two electromagnetic waves (represented by a black line and a gray line) emitted from the phase center of the feed source is . The electromagnetic wave represented by the black line is reflected by the center point of the secondary reflector and then transmitted to the center point of the primary reflector. After being reflected by the center point of the primary reflector, it is transmitted to the antenna aperture. The electromagnetic wave represented by the gray line is transmitted to the point (ρ1, θ1) on the secondary reflector (where ρ1 = ρ0 + dρ and θ1 = θ0 + dθ). After being reflected by this point, it is transmitted to the point (x1, z1) on the primary reflector (where x1 = x0 + dx and z1 = z0 + dz). After being reflected by this point, it is transmitted to the antenna aperture. According to Snell's reflection law, the incident angle and reflection angle of these two electromagnetic waves on the main reflecting surface are equal, and the incident angle and reflection angle of each on the secondary reflecting surface are equal. Therefore, the functional relationship of dρ with respect to dθ can be determined, and then the functional relationship of ρ1 with respect to dθ can be determined to complete the shaping of the secondary reflecting surface.

[0062] The third step is based on the law of conservation of energy, such as Figure 2 As shown, the energy of the electromagnetic wave incident on the secondary reflector dθ by the phase center of the feed source is equal to the energy of the electromagnetic wave reflected by the primary reflector in dx, thus formula (1) can be obtained:

[0063]

[0064] Where P(x)=p 2 (x), F(x)=f 2 (x), according to formula (1), the functional relationship of dx on dθ can be determined, and then the functional relationship of x1 on dθ can be determined.

[0065] The fourth step is based on the law of equal optical path length. Figure 2 The black line in the middle represents the distance of the electromagnetic wave from the phase center of the feed to the antenna aperture, which is consistent with Figure 2 The electromagnetic wave represented by the medium gray line travels the same distance from the phase center of the feed source to the antenna aperture. That is, the sum of the distances from the phase center of the feed source to point (ρ0, θ0), from point (ρ0, θ0) to point (x0, z0), and from point (x0, z0) to the antenna aperture is equal to the sum of the distances from the phase center of the feed source to point (ρ1, θ1), from point (ρ1, θ1) to point (x1, z1), and from point (x1, z1) to the antenna aperture. Based on this equal distance relationship, we can determine the functional relationship of dz with respect to dθ, and further determine the functional relationship of z1 with respect to dθ. The functional relationship of x1 with respect to dθ obtained in the third step and the functional relationship of z1 with respect to dθ obtained in the fourth step are used to shape the main reflector.

[0066] The above example introduces the implementation method of antenna shaping through the three constraints of Snell's reflection law, energy conservation law and equal optical path law. In the shaping process of the antenna with a spherical main reflector, after determining the functional relationship of x1 with respect to dθ, since the main reflector is spherical, x1 and z1 need to satisfy x1 2 +z1 2 =r0 2 , where r0 is the radius of the sphere where the main reflector is located. The z1 determined under this relationship cannot satisfy the equal optical path law in the fourth step above. Therefore, the antenna with a spherical main reflector needs to introduce an optical path difference through an additional sub-reflector, so as to meet the above three constraints in the shaping process and optimize the antenna gain. However, the introduction of additional sub-reflectors will increase the complexity of the antenna system.

[0067] The reflector antenna in the embodiment of the present application can be based on a metasurface, which improves the above-mentioned problems existing in the reflector antenna whose main reflector is spherical. The metasurface is briefly introduced below.

[0068] A metasurface is a two-dimensional metasurface array composed of metasurface units with periodic or non-periodic structures at the sub-wavelength scale. Figure 3 As shown, Figure 3 is a schematic diagram of a metasurface unit provided in an embodiment of the present application, Figure 3 The multiple metasurface units are evenly distributed, and the structures within the multiple metasurface units can be arranged periodically or non-periodically. Figure 4 As shown, Figure 4 This is another schematic diagram of a metasurface unit provided in an embodiment of the present application. Figure 4 The metasurface units are periodically arranged. When electromagnetic waves are reflected or transmitted, the metasurface array can control the electromagnetic wave's amplitude, phase, polarization, and other electromagnetic properties. In the embodiments of the present application, the metasurface controls the phase of the electromagnetic wave, enabling the spherical reflector antenna to satisfy the three constraints of Snell's reflection law, the law of conservation of energy, and the law of equal optical path length during the shaping process. This results in a simple reflector antenna system with a spherical main reflector after shaping, and excellent antenna gain.

[0069] In one approach, a metasurface unit can be implemented using metal structures of different structures. Specifically, the metasurface unit may include a dielectric layer, a reflective layer, and a metal structure layer, wherein one surface of the dielectric layer is printed with a reflective layer, and the other surface of the dielectric layer is printed with a metal structure layer. The dielectric layer may be high-resistance silicon, FR4 (a code for a grade of heat-resistant material), or the like. The reflective layer is used to reflect electromagnetic waves and may be a grounded metal reflective surface (such as a copper reflective surface, an aluminum reflective surface, etc.). The metal structure layer may be a metal structure of different shapes or sizes, such as a metal rectangular ring, a metal circular ring, a metal polygonal ring, and the like. See [Referring to] Figure 5 , Figure 5 Schematic diagram of the metasurface metal structure provided in the embodiment of this application, Figure 5 exemplarily shows different metal structures in the metal structure layer.

[0070] See Figure 6 , Figure 6 This is an example diagram of a metasurface unit provided in an embodiment of the present application, such as Figure 6 As shown, in Figure 6 From the perspective of , the metal structure layer supported by the upper surface of the dielectric layer in the metasurface unit is a metal rectangular ring, and the lower surface of the dielectric layer is a reflective layer. When an electromagnetic wave is incident from above the metasurface unit, the phase of the reflected electromagnetic wave can be controlled. The incident electromagnetic wave can be represented by x, and the reflected electromagnetic wave can be represented by xe jθ In an exemplary control method, the phase θ of the reflected electromagnetic wave can be controlled by adjusting the length and width of the metal rectangular ring or adjusting the width of the metal strip of the metal rectangular ring.

[0071] In one approach, metasurface units can be implemented by loading a metasurface onto a liquid crystal array. Specifically, the metasurface units can include a lattice containing liquid crystals. When electromagnetic waves are incident on the liquid crystals, the liquid crystals manipulate the phase of the incident electromagnetic waves, which are then transmitted through the liquid crystals. Different bias voltages can be applied to the liquid crystals to adjust their dielectric constant, thereby adjusting their ability to phase-modulate the incident electromagnetic waves.

[0072] The following introduces the reflector antenna provided in the embodiment of the application. The reflector antenna provided in the embodiment of the present application can be used to transmit electromagnetic waves. The reflector antenna can realize a spherical reflector antenna with a simple system and high antenna gain by phase controlling the transmitted electromagnetic waves.

[0073] For details, see Figure 7 , Figure 7 This is a schematic diagram of the structure of a reflector antenna provided in an embodiment of the present application. Figure 7 As shown, the reflector antenna may include at least a primary reflector panel and a feed structure, wherein the feed structure includes a feed source and a secondary reflector panel, and the distance and relative posture between the feed source and the secondary reflector panel are fixed. Optionally, the reflector antenna may also include other components, such as a bracket for fixing the reflector antenna.

[0074] The primary reflector is a spherical panel. The feed structure rotates relative to the primary reflector around the center of the sphere on which the primary reflector resides. The secondary reflector is equipped with a metasurface array on its first surface. The feed generates electromagnetic waves. The secondary reflector controls the phase of the electromagnetic waves generated by the feed via its first surface and transmits the phase-controlled electromagnetic waves to the primary reflector via its first surface. The primary reflector reflects the phase-controlled electromagnetic waves.

[0075] In this reflector antenna, the sub-reflector panel realizes phase control of the electromagnetic waves to be emitted through the first surface covered with a metasurface array, so that the reflector antenna can simultaneously satisfy Snell's reflection law, the law of conservation of energy and the law of equal optical path length, reducing the system complexity caused by the use of multiple sub-reflector panels, while ensuring that the reflector antenna has a better system gain.

[0076] Among them, in an alternative manner, the feed source may include a horn feed source, a vibrator feed source, a double-slot feed source and the like, and the feed source may be a forward feed source, a backward feed source or a bias feed source. It should be understood that in the embodiment of the present application, when introducing the shaping of the sub-reflecting surface or the design process of the metasurface array of the first surface, the feed source can be approximately regarded as an electromagnetic wave emission source with a phase center, that is, the electromagnetic wave emitted by the feed source can be understood as an electromagnetic wave emitted from one point and having the same phase. However, in the actual manufacturing and use process, the electromagnetic wave emitted by the feed source may usually have a certain error in its emission point and phase. Theoretically, if the feed source of the reflector antenna in this embodiment emits an electromagnetic wave that is emitted from one point and has the same phase, then the antenna ultimately emitted from the main reflector panel is a parallel electromagnetic wave, which can maximize the antenna gain and antenna efficiency of the reflector antenna.

[0077] The main reflective panel can be made of aluminum, copper, titanium, magnesium, stainless steel, glass fiber with metal coating, etc. The main reflective panel can be in the form of a plate, or in the form of a plate with a transparent structure or a mesh.

[0078] The metasurface array arranged on the first surface of the secondary reflective panel can be realized by a metal structure or a liquid crystal array.

[0079] If the metasurface array disposed on the first surface of the secondary reflector is implemented using a metal structure, the metasurface array on the first surface may include a phase control layer, a dielectric layer, and a reflective layer. The phase control layer includes a plurality of metasurface units uniformly arranged on the dielectric layer, each metasurface unit including a metal structure. The reflective layer is configured to reflect electromagnetic waves that pass through the phase control layer and the dielectric layer.

[0080] Furthermore, the structural shapes of the metal structures of different metasurface units in the multiple metasurface units are not exactly the same, that is, in the multiple metasurface units, the structural shapes of the metal structures of each metasurface unit may be different, or some of the structural shapes may be the same.

[0081] If the metasurface array disposed on the first surface of the secondary reflector is implemented using a liquid crystal array, the metasurface array on the first surface comprises a plurality of uniformly arranged metasurface units, each of which comprises a lattice containing liquid crystals. The liquid crystals in the lattice are used to phase-modulate the electromagnetic waves generated by the feed source by applying a bias voltage, and to transmit the phase-modulated electromagnetic waves.

[0082] Furthermore, the bias voltages loaded on the liquid crystals in different lattices among the multiple lattices are not exactly the same, that is, the bias voltages loaded on the liquid crystals in each lattice among the multiple lattices may be different, or the bias voltages loaded on the liquid crystals in some lattices may be the same.

[0083] Furthermore, in one method, the electromagnetic waves can be transmitted to the main reflective panel after being phase-controlled by the liquid crystal. In another method, the lower part of the metasurface array on the secondary reflective panel also includes a reflective layer that can reflect the electromagnetic waves that pass through the liquid crystal. That is to say, after the electromagnetic waves are phase-controlled by the liquid crystal, they can be reflected to the main reflective panel through the reflective layer.

[0084] The distance and relative posture between the feed source and the sub-reflection panel in the feed structure remain unchanged, including no relative displacement and no relative rotation between the feed source and the sub-reflection panel. In an alternative implementation method, the feed source and the sub-reflection panel in the feed structure can be fixed by a bracket, etc. to ensure that the relative distance and relative posture between the two remain unchanged.

[0085] It should be noted that the feed structure includes the feed source and the sub-reflector panel as a whole feed structure, which can rotate relative to the center of the sphere where the main reflector panel is located. However, within the feed structure, the feed source does not rotate or displace relative to the sub-reflector panel. For example, if the feed source is a horn feed source and the first surface of the sub-reflector panel is a plane, the relative posture of the two can be that the horn opening of the feed source is opposite to the front of the first surface, and the distance between the horn opening and the first surface is 10m. Then, during the operation of the transmitting surface antenna, the feed source and the sub-reflector panel always maintain the posture of the horn opening facing the front of the first surface, and the distance between the horn opening and the first surface always remains 10m.

[0086] By maintaining a fixed relative distance and relative posture between the two, the distance from the feed source to each point on the secondary reflector panel is fixed during use of the reflector antenna, thereby ensuring that the reflector antenna can satisfy the equal optical path law in all emission directions of electromagnetic waves.

[0087] The feed structure can be used to rotate relative to the main reflector panel around the center of the sphere where the main reflector panel is located. In an alternative implementation, the relative position of the main reflector panel and the center of the sphere where the main reflector panel is located remains unchanged, and the feed can be used to rotate around the center of the sphere where the main reflector panel is located. In other words, the position of the main reflector panel can be fixed, and the position of the feed structure is not fixed, and it can rotate around the center of the sphere where the main reflector panel is located. For example, after the reflector antenna is installed, the position of the main reflector panel on the mounting bracket is fixed and cannot be moved or rotated, and the feed structure has a rotatable axis on the mounting bracket.

[0088] In another alternative implementation, the relative position of the feed structure and the center of the sphere on which the main reflector panel resides remains unchanged, while the main reflector panel is configured to rotate about the center of the sphere on which the main reflector panel resides. In other words, the position of the feed structure can be fixed, while the position of the main reflector panel is not fixed, and it can rotate about the center of the sphere on which the main reflector panel resides. For example, after the reflector antenna is installed, the position of the feed structure on the mounting bracket is fixed, immovable, and cannot rotate, while the main reflector panel can have a rotational axis on the mounting bracket.

[0089] The above relative position includes relative direction and relative distance. The invariable relative position means that the relative direction of the two in space and the relative distance in this direction remain unchanged.

[0090] By providing a relatively rotatable structure between the feed structure and the main reflective panel, the feed structure and the main reflective panel can have different relative angles, thereby satisfying the emission of electromagnetic waves in different directions.

[0091] In an alternative implementation, the first surface may be a plane on the secondary reflective panel, and the shape of the secondary reflective panel may not be limited. For example, see Figure 8 , Figure 8 A schematic plan view of a secondary reflective panel provided in an embodiment of the present application, Figure 8 (6a)-(6e) show schematic cross-sectional views of five types of sub-reflection panels, respectively. Among them, the sub-reflection panel shown in (6a) has a rectangular cross-section, and the first surface is a plane, which is represented by one side of the rectangular cross-section. The sub-reflection panel shown in (6b) has a cross-section that includes an arc edge, and the first surface is a plane, which is represented by one side of the cross-section. The sub-reflection panel shown in (6c) has a pentagonal cross-section, and the first surface is a plane, which is represented by one side of the pentagonal cross-section. It should be noted that the first surface can be a plane on the sub-reflection panel, or it can be multiple planes on the sub-reflection panel, such as Figure 8In (6d), the cross section of the secondary reflective panel is a pentagon, and the first surface is a surface formed by connecting two planes, which is represented by two sides in the pentagonal cross section.

[0092] In an alternative implementation, the first surface may be a curved surface, such as a spherical surface, a paraboloid, etc. Figure 8 In (6e), the cross section of the secondary reflector panel includes an arc edge, and the arc edge represents a spherical surface of the secondary reflector panel. The first surface is the spherical surface, which is represented by the arc in (6e).

[0093] Different metasurface units in the first surface may have different phase control capabilities for electromagnetic waves of the same wavelength. That is, among the multiple metasurface units in the first surface, the phase control capabilities of each metasurface unit for electromagnetic waves of the same wavelength may be different, or some metasurface units may have the same phase control capabilities for electromagnetic waves of the same wavelength. The phase control capability of a metasurface unit for electromagnetic waves is determined based on the distance from the metasurface unit to the feed source, the distance from the metasurface unit to the reflection position of the primary reflector corresponding to the metasurface unit, and the distance from the reflection position of the primary reflector corresponding to the metasurface unit to the aperture of the reflector antenna.

[0094] The reflection position of the main reflection surface corresponding to the metasurface unit is the position where the electromagnetic wave emitted from the feed source reaches the main reflection panel after being reflected by the metasurface unit. Figure 2 As shown in Figure 2 The secondary reflector is the first surface on which the metasurface array is arranged. The reflection position of the primary reflector corresponding to the metasurface unit located at point (ρ0, θ0) is point (x0, z0), and the reflection position of the primary reflector corresponding to the metasurface unit located at point (ρ1, θ1) is point (x1, z1).

[0095] Among them, the distance from a certain metasurface unit to the feed source, the distance from the metasurface unit to the reflection position of the main reflection surface corresponding to the metasurface unit, and the distance from the reflection position of the main reflection surface corresponding to the metasurface unit to the aperture of the reflection surface antenna. The sum of these three distances determines the distance of the electromagnetic wave emitted from the feed source, passing through the metasurface unit, and finally reaching the aperture of the reflection surface antenna. Based on this distance, the phase difference for phase compensation of the metasurface unit can be determined, and based on this phase difference, the phase control ability of the metasurface unit on the electromagnetic wave can be set.

[0096] Furthermore, for any two metasurface units in the metasurface array of the first surface, respectively denoted as the first metasurface unit and the second metasurface unit, the sub-reflective panel can be specifically used to perform phase compensation of a first phase difference on the electromagnetic wave through the first metasurface unit, and to perform phase compensation of a second phase difference on the electromagnetic wave through the second metasurface unit. Then, the first phase difference and the second phase difference can satisfy the following formula (2):

[0097]

[0098] in, is the first phase difference, l1 is the distance from the first metasurface unit to the feed source, l2 is the distance from the first metasurface unit to the reflection position of the main reflection surface corresponding to the first metasurface unit, l3 is the distance from the reflection position of the main reflection surface corresponding to the first metasurface unit to the aperture of the reflection surface antenna, λ is the wavelength of the electromagnetic wave, is the second phase difference, l4 is the distance from the second metasurface unit to the feed source, l5 is the distance from the second metasurface unit to the reflection position of the main reflection surface corresponding to the second metasurface unit, and l6 is the distance from the reflection position of the main reflection surface corresponding to the second metasurface unit to the aperture of the reflection surface antenna.

[0099] That is to say, for any two metasurface units on the first surface, after phase compensation of the metasurface units, the phase of the aperture reaching the reflector antenna can be made the same, thereby satisfying the equal optical path law and ensuring the optimal antenna gain of the reflector antenna.

[0100] The following is an example of a design process for a metasurface array for the first surface. This design process can be implemented based on the three constraints of Snell's law of reflection, the law of conservation of energy, and the law of equal optical path length. Figure 9 , Figure 9 This is a schematic diagram of a reflector antenna provided in an embodiment of the present application, in which various points of the main reflector panel are represented by orthogonal coordinates. Figure 9 The first surface shown in the figure is a plane, and each point on the first surface is represented by the coordinates of the spherical coordinate system. The design process in the ZOX plane is taken as an example. Any other plane perpendicular to the Y axis can be designed by referring to this process. That is, let y = 0 in the coordinates of each point on the main reflection surface, and let the coordinates of each point on the first surface be Assume that the coordinates of the center point of the main reflective panel are (x0, z0), for any point (x, z) on the main reflective panel, the maximum value of x is x max The coordinates of the center point of the first surface are (ρ0, θ0). For any point (ρ, θ) on the secondary reflector, the maximum value of θ is θ maxIn addition, p(x) is the aperture field distribution function specified for the antenna, f(θ) is the radiation pattern of the antenna feed, (x0, z0), x max , (ρ0, θ0), θ max , p(x), and f(θ) are all known parameters. The design of the metasurface array of the first surface can be achieved through the following process:

[0101] Step 1: Determine the phase control capabilities of metasurface units with different parameters. For example, if the metasurface array on the first surface is implemented using a metal structure, the first step can determine the phase difference corresponding to metasurface units of different shapes. If the metasurface array on the first surface is implemented using liquid crystal, the first step can determine the phase difference corresponding to different bias voltage values ​​applied to the lattice.

[0102] Step 2: Initialize and set θ from θ0 to θ max The step length is dθ.

[0103] Step 3: If Figure 9 As shown, the angle between the two electromagnetic waves (represented by a black line and a gray line) emitted from the phase center of the feed source is dθ. The electromagnetic wave represented by the black line is reflected by the center point of the first surface and then transmitted to the center point of the main reflector panel. After reflection from the center point of the main reflector panel, it is transmitted to the aperture of the antenna. The electromagnetic wave represented by the gray line is transmitted to the point (ρ1, θ1) on the first surface (where ρ1 = ρ0 + dρ and θ1 = θ0 + dθ). After reflection from this point, it is transmitted to the point (x1, z1) on the main reflector panel (where x1 = x0 + dx and z1 = z0 + dz). After reflection from this point, it is transmitted to the aperture of the antenna. According to Snell's reflection law, the incident angle and reflection angle of each of these two electromagnetic waves on the main reflector are equal, and the incident angle and reflection angle of each of these two electromagnetic waves on the secondary reflector are equal. Therefore, the functional relationship of dρ with respect to dθ can be determined, and the functional relationship of ρ1 with respect to dθ can be determined.

[0104] Step 4: According to the law of conservation of energy, Figure 9 As shown, the energy of the electromagnetic wave incident on the first surface dθ by the phase center of the feed source is equal to the energy of the electromagnetic wave reflected by the main reflective panel in x, so the following formula (3) can be obtained:

[0105]

[0106] Where P(x)=p 2 (x), F(x)=f 2 (x), according to the above formula (3), the functional relationship of dx on dθ can be determined, and then the functional relationship of x1 on dθ can be determined.

[0107] Since the point (x1, z1) is a point on the sphere, it satisfies the spherical formula (x1-x3) 2 +(z1-z3) 2 =r0 2 , where (x3, z3) are the coordinates of the center of the sphere where the main reflection panel is located, which are known parameters. Then, the functional relationship of z1 with respect to dθ can be determined based on the functional relationship of x1 with respect to dθ and the above spherical formula.

[0108] Step 5: If Figure 9 As shown in Figure 9 The distance that the electromagnetic wave represented by the black line travels from the phase center of the feed source to the aperture of the reflector antenna is l1+l2+l3, where l1 can be determined based on the coordinates of the phase center of the feed source and the coordinates (ρ0, θ0), l2 can be determined based on the coordinates (ρ0, θ0) and the coordinates (x0, z0), and l3 can be determined based on the coordinates (x0, z0) and the equation of the plane where the aperture of the reflector antenna is located. The above coordinates or equations are all known, so l1+l2+l3 is known, and then, Figure 9 The phase of the electromagnetic wave reaching the aperture of the reflector antenna, represented by the black line in the middle, is ψ1 = 2π × (l1 + l2 + l3) / λ, which is a known quantity.

[0109] Figure 9 The distance that the electromagnetic wave represented by the medium gray line travels from the phase center of the feed source to the aperture of the reflector antenna is l4+l5+l6, where l4 can be determined based on the coordinates of the phase center of the feed source and the coordinates (ρ1, θ1), l5 can be determined based on the coordinates (ρ1, θ1) and the coordinates (x1, z1), and l6 can be determined based on the coordinates (x1, z1) and the equation of the plane where the aperture of the reflector antenna is located. The functional relationships of ρ1, θ1, x1, and z1 in the above coordinates or equations with respect to dθ are all determined through the above steps, so the functional relationship of l4+l5+l6 with respect to dθ can be obtained.

[0110] and then, Figure 9 The phase ψ2 of the electromagnetic wave reaching the aperture of the reflector antenna, represented by the medium gray line, can be expressed by the formula ψ2 = 2π×(l4+l5+l6) / λ, and the functional relationship of ψ2 with respect to dθ can be obtained.

[0111] According to the law of equal optical path length, in order to ensure Figure 9 The gray line represents the phase ψ2 of the electromagnetic wave reaching the aperture of the reflector antenna, which is Figure 9The phase ψ1 of the electromagnetic wave represented by the black line reaching the aperture of the reflector antenna is equal. Then, when the phase control of the electromagnetic wave at the center point of the first surface is zero, the metasurface unit at (ρ1, θ1) on the first surface needs to have a phase compensation capability of a phase difference of ψ1-ψ2 for the electromagnetic wave with a wavelength of λ. In other words, the functional relationship of the phase difference ψ1-ψ2 with respect to dθ is obtained.

[0112] Step 6: In the fifth step, the functional relationship of the phase difference ψ1-ψ2 with respect to dθ is obtained, that is, for any determined value of θ, the phase difference of the corresponding metasurface unit on the first surface can be determined. Then, according to the phase difference and the phase control capability corresponding to the metasurface units with different parameters determined in the first step, the parameters of the corresponding metasurface units are selected, such as the shape of the metal structure, or the bias voltage value corresponding to the liquid crystal in the lattice.

[0113] It should be understood that in the above-mentioned fifth step, if the phase control of the electromagnetic wave by the center point of the first surface is a non-zero value ψ0, the metasurface unit at (ρ1, θ1) on the first surface needs to have a phase compensation capability of a phase difference of ψ0+ψ1-ψ2 for the electromagnetic wave with a wavelength of λ, that is, the phase difference of the compensation of the electromagnetic wave by each metasurface unit needs to be more than the constant ψ0. The parameters corresponding to each metasurface unit can still be determined by referring to the process of the above-mentioned sixth step.

[0114] It should be noted that the above process is only Figure 9 The above process is described for the case where the first surface is a plane. The first surface can also be non-planar. In the case of a non-planar surface, the parameters of each metasurface unit in the metasurface array can also be determined by referring to the above process. In addition, the above process is described as an example of the process in which the electromagnetic wave is reflected by the secondary reflective panel and then transmitted to the main reflective panel. In the case where the electromagnetic wave is transmitted through the secondary reflective panel and then transmitted to the main reflective panel, the parameters of each metasurface unit in the metasurface array can also be determined by referring to the above process. These will not be described in detail here.

[0115] An embodiment of the present application also provides a reflector antenna that can be used to receive electromagnetic waves. The reflector antenna can realize a spherical reflector antenna with a simple system and high antenna gain by phase-controlling the received electromagnetic waves.

[0116] For details, see Figure 10 , Figure 10 This is a schematic diagram of the structure of a reflector antenna provided in an embodiment of the present application. Figure 10As shown, the reflector antenna may include a primary reflector panel and a receiving structure. The receiving structure includes a receiver and a secondary reflector panel. The distance and relative position between the receiver and the secondary reflector panel are fixed. The primary reflector panel is a spherical panel. The receiving structure is configured to rotate relative to the primary reflector panel around the center of the sphere on which the primary reflector panel resides. The secondary reflector panel has a metasurface array arranged on its second surface.

[0117] The primary reflective panel is configured to receive and reflect electromagnetic waves. The secondary reflective panel is configured to phase-modulate the electromagnetic waves reflected by the primary reflective panel via a second surface and transmit the phase-modulated electromagnetic waves to a receiver via the second surface. The receiver is configured to receive and process the electromagnetic waves transmitted by the secondary reflective panel. Processing of the electromagnetic waves by the receiver may include converting the electromagnetic waves from radio frequency signals to baseband signals.

[0118] In this reflector antenna, the sub-reflector panel realizes phase control of the received electromagnetic waves through the second surface equipped with a metasurface array, so that the reflector antenna can simultaneously satisfy Snell's reflection law, the law of conservation of energy and the law of equal optical path length, reducing the system complexity caused by the use of multiple sub-reflector panels while ensuring that the reflector antenna has a better system gain.

[0119] It should be understood that if the electromagnetic waves received by the main reflecting panel are parallel incident electromagnetic waves, then the electromagnetic waves reflected by the main reflecting panel and the secondary reflecting panel of the reflecting surface antenna of this embodiment will converge at the receiver, thereby maximizing the efficiency of the receiver in receiving electromagnetic waves.

[0120] In one alternative implementation, the relative position of the main reflective panel and the center of the spherical surface on which the main reflective panel is located remains unchanged, and the receiving structure is configured to rotate about the center of the spherical surface on which the main reflective panel is located. In another alternative implementation, the relative position of the main reflective panel and the center of the spherical surface on which the main reflective panel is located remains unchanged, and the receiving structure is configured to rotate about the center of the spherical surface on which the main reflective panel is located. By enabling relative rotation between the receiving structure and the main reflective panel, different relative angles can be set between the receiving structure and the main reflective panel, thereby satisfying the reception of electromagnetic waves in different directions.

[0121] The second surface can be a flat surface or a curved surface on the secondary reflective panel. The metasurface array arranged on the second surface of the secondary reflective panel can be implemented by a metal structure or a liquid crystal array.

[0122] If the metasurface array arranged on the second surface is realized by a metal structure, the metasurface array on the second surface includes a phase control layer, a dielectric layer and a reflective layer. The phase control layer includes a plurality of metasurface units uniformly arranged on the dielectric layer, and each metasurface unit includes a metal structure. The reflective layer is used to reflect electromagnetic waves passing through the phase control layer and the dielectric layer. Furthermore, the structural shapes of the metal structures of different metasurface units in the multiple metasurface units are not exactly the same, that is, the structural shapes of the metal structures of the various metasurface units in the multiple metasurface units may be different, or some of the structural shapes may be the same.

[0123] If the metasurface array arranged on the second surface is implemented by a liquid crystal array, the metasurface array on the second surface includes a plurality of uniformly arranged metasurface units, each of which includes a lattice containing liquid crystals. The liquid crystals in the lattice are used to phase-control the electromagnetic waves generated by the feed source by applying a bias voltage, and to transmit the electromagnetic waves after phase control. Furthermore, the bias voltages applied to the liquid crystals in different lattices among the multiple lattices are not exactly the same. That is, the bias voltages applied to the liquid crystals in each lattice among the multiple lattices may be different, or the bias voltages applied to the liquid crystals in some lattices may be the same.

[0124] The biggest difference between the reflector antenna for receiving electromagnetic waves introduced in this embodiment and the reflector antenna for sending electromagnetic waves introduced above is that the transmission direction of the electromagnetic waves is opposite. In addition, the preparation materials of the main reflector panel and the sub-reflector panel can refer to the corresponding introduction in the above embodiment of the reflector antenna for transmitting electromagnetic waves; the implementation of the second surface of the sub-reflector panel can refer to the specific introduction of the implementation of the first surface of the sub-reflector panel in the above embodiment of the reflector antenna for transmitting electromagnetic waves; the position introduction of the main reflector panel and the receiving structure can refer to the corresponding introduction of the main reflector panel and the feed structure in the above embodiment of the reflector antenna for transmitting electromagnetic waves; the method for determining the specific parameters of each super-surface unit in the super-surface array arranged on the second surface can refer to the method for determining the specific parameters of each super-surface unit in the super-surface array arranged on the first surface in the above embodiment of the reflector antenna for transmitting electromagnetic waves, and they will not be repeated here.

[0125] The embodiment of the present application also provides a beam control method, which can be applied to a reflector antenna. The reflector antenna includes a main reflector panel and a feed structure. The feed structure includes a feed source and a sub-reflector panel. The distance and relative posture between the feed source and the sub-reflector panel are fixed. The main reflector panel is a spherical panel. The feed structure is used to rotate relative to the main reflector panel around the center of the sphere where the main reflector panel is located; the first surface of the sub-reflector panel is covered with a metasurface array. For example, this method can be applied to any of the reflector antennas provided in the embodiment of the reflector antenna for emitting electromagnetic waves introduced above, such as Figure 7 The reflector antenna shown.

[0126] In this method, electromagnetic waves can be generated at the feed source, sent to the first surface of the secondary reflector, the phase of the electromagnetic waves generated by the feed source is controlled by the first surface, the electromagnetic waves after phase control are sent to the main reflector, and the electromagnetic waves after phase control are reflected at the main reflector.

[0127] This method controls the phase of the electromagnetic waves to be emitted through the first surface of the sub-reflector panel, so that the electromagnetic waves emitted from the feed source satisfy Snell's reflection law, the law of conservation of energy and the equal optical path law during the process of transmission to the aperture of the reflector antenna, thereby improving the antenna gain and antenna efficiency of the reflector antenna.

[0128] The embodiment of the present application also provides another beam control method, which can be applied to a reflector antenna, wherein the reflector antenna includes a main reflector panel and a receiving structure, wherein the receiving structure includes a receiver and a sub-reflector panel, and the relative positions of the receiver and the sub-reflector panel are fixed. The main reflector panel is a spherical panel, and the receiving structure is used to rotate relative to the main reflector panel around the center of the sphere where the main reflector panel is located, and the second surface of the sub-reflector panel is provided with a metasurface array. For example, this method can be applied to any of the reflector antennas provided in the embodiment of a reflector antenna for receiving electromagnetic waves described above, such as Figure 10 The reflector antenna shown.

[0129] In this method, electromagnetic waves transmitted to the main reflecting panel can be received, the received electromagnetic waves can be emitted at the main reflecting panel, and the phase of the electromagnetic waves reflected by the main reflecting panel can be controlled through the second surface; the phase-controlled electromagnetic waves can be sent to the receiver, and the phase-controlled electromagnetic waves can be received and processed at the receiver.

[0130] This method uses the second surface of the secondary reflector to control the phase of the electromagnetic waves to be transmitted, so that the electromagnetic waves received by the main reflector satisfy Snell's reflection law, the law of conservation of energy and the equal optical path law during the process of transmission to the receiver, thereby improving the antenna gain and antenna efficiency of the reflector antenna.

[0131] An embodiment of the present application also provides a communication device, which may include any one of the reflector antennas provided in the embodiment of a reflector antenna for transmitting electromagnetic waves introduced above, and / or any one of the reflector antennas provided in the embodiment of a reflector antenna for receiving electromagnetic waves introduced above.

[0132] See Figure 11 , Figure 11 is a schematic diagram of a communication system provided by an embodiment of the present application, the communication system may include at least one transmitting device and at least one receiving device, such as Figure 11 As shown, Figure 11 exemplarily shows a sending device and two receiving devices, where the two receiving devices are receiving device 1 and receiving device 2 respectively.

[0133] The above-mentioned transmitting device is used to transmit electromagnetic waves. The transmitting device can be an evolved Node B (eNB), a radio network controller (RNC), a Node B (NB), a base station controller (BSC), a base transceiver station (BTS), a home base station (for example, a home evolved NodeB, or a home Node B, HNB), a baseband unit (BBU), an access point (AP) in a wireless fidelity (WIFI) system, a wireless relay node, a wireless backhaul node, a transmission point (TP) or a transmission and reception point (TRP), etc. It can also be a gNB in ​​a 5G, such as an NR (new radio) system, or a transmission point (TRP or TP), one or a group of antenna panels of a base station in a 5G system, etc., without exhaustive list.

[0134] The receiving device is used to receive electromagnetic waves. The transmitting device can be an evolved node B, a radio network controller, a node B, a base station controller, a base transceiver station, a home base station, a baseband unit, an access point, a wireless relay node, a wireless backhaul node, a transmission point, or a transmitting and receiving point in a wireless fidelity system. It can also be a 5G, such as a gNB in ​​an NR system, or a transmission point, one or a group of antenna panels of a base station in a 5G system, or a user equipment (UE), a mobile station, or a remote station. It is a network device with wireless receiving capabilities. The terminal can be deployed on land, including indoors or outdoors, handheld, wearable, or vehicle-mounted; it can also be deployed on water (such as a ship); it can also be deployed in the air (such as an airplane, balloon, and satellite). Specifically, it can be a mobile phone, a tablet computer, a computer with wireless transceiver capabilities, a virtual reality (VR) terminal device, an augmented reality (AR) terminal device, a wireless terminal in industrial control (industrial control), a wireless terminal in self-driving (self-driving), or a remote medical device. Medical), wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, etc., are not exhaustive.

[0135] The at least one transmitting device may include any one of the reflector antennas provided in the embodiment of the reflector antenna for transmitting electromagnetic waves described above (e.g. Figure 7 The reflector antenna shown in FIG. 1 ), and / or the at least one receiving device may include any one of the reflector antennas provided in the embodiment of the reflector antenna for receiving electromagnetic waves described above (such as Figure 10 reflector antenna shown).

[0136] If the at least one transmitting device includes any one of the reflector antennas provided in the embodiment of the reflector antenna for transmitting electromagnetic waves described above, and the at least one receiving device includes any one of the reflector antennas provided in the embodiment of the reflector antenna for receiving electromagnetic waves described above, then during use, the transmitting device can align the reflector antenna of the transmitting device and the reflector antenna of the receiving device with each other (for example) by relative rotation between the main reflector panel and the feed structure, and the receiving device can align the reflector antenna of the transmitting device and the reflector antenna of the receiving device with each other (for example) by relative rotation between the main reflector panel and the receiving structure. Figure 11The transmitting device and the receiving device 1 are adjusted so that their respective reflective antennas are aligned with each other), so that the gain of the transmitting device transmitting electromagnetic waves is maximized, and the gain of the receiving device receiving electromagnetic waves is maximized, thereby maximizing the system gain.

[0137] It should be noted that, in the description of the embodiments of this application, unless otherwise specified, " / " represents the meaning of "or." For example, A / B can represent A or B. "And / or" in this article is merely a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. Furthermore, in the description of the embodiments of this application, "plurality" refers to two or more than two.

[0138] The terms "first," "second," "third," and "fourth," etc., in the specification and claims of this application and the accompanying drawings are used to distinguish different objects, not to describe a specific order. In addition, the terms "including," "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, or product that includes a series of steps or devices is not limited to the listed steps or devices, but may optionally include steps or devices not listed, or may optionally include other steps or devices inherent to the process, method, or product.

[0139] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A reflector antenna, characterized in that: It includes a main reflection panel and a feed structure, wherein the feed structure includes a feed and a sub-reflection panel, and the distance and relative posture between the feed and the sub-reflection panel are fixed; The main reflective panel is a spherical panel; the feed structure is used to rotate relative to the main reflective panel around the center of the sphere on which the main reflective panel is located; the first surface of the secondary reflective panel is covered with a metasurface array; The feed source is used to generate electromagnetic waves; The secondary reflective panel is used to perform phase control on the electromagnetic wave generated by the feed source through the first surface, and send the phase-controlled electromagnetic wave to the primary reflective panel through the first surface; The main reflection panel is used to reflect the phase-controlled electromagnetic waves.

2. The reflector antenna according to claim 1, wherein: The relative position of the main reflection panel and the center of the spherical surface where the main reflection panel is located remains unchanged, and the feed structure is used to rotate around the center of the spherical surface where the main reflection panel is located.

3. The reflector antenna according to claim 1, wherein: The relative position of the feed structure and the center of the spherical surface where the main reflection panel is located remains unchanged, and the main reflection panel is used to rotate around the center of the spherical surface where the main reflection panel is located.

4. The reflector antenna according to any one of claims 1 to 3, characterized in that: The first surface is a plane on the secondary reflective panel, or a curved surface on the secondary reflective panel.

5. The reflector antenna according to claim 1, wherein: The metasurface array of the first surface includes a phase control layer, a dielectric layer and a reflective layer; The phase control layer includes a plurality of metasurface units uniformly arranged on the dielectric layer, wherein one of the metasurface units includes a metal structure; The reflective layer is used to reflect electromagnetic waves passing through the phase control layer and the dielectric layer.

6. The reflector antenna according to claim 1, wherein: The metasurface array of the first surface includes a plurality of uniformly arranged metasurface units, wherein one of the metasurface units includes a lattice containing liquid crystal; The liquid crystal in the lattice is used to perform phase control on the electromagnetic wave generated by the feed source by applying a bias voltage, and is used to transmit the electromagnetic wave after the phase control.

7. The reflector antenna according to claim 5 or 6, characterized in that: The two metasurface units have different phase control capabilities for electromagnetic waves of the same wavelength; The phase control capability of the metasurface unit for electromagnetic waves is determined based on the distance from the metasurface unit to the feed source, the distance from the metasurface unit to the reflection position of the main reflection surface corresponding to the metasurface unit, and the distance from the reflection position of the main reflection surface corresponding to the metasurface unit to the aperture of the reflection surface antenna; wherein, the reflection position of the main reflection surface corresponding to the metasurface unit is the position where the electromagnetic wave emitted from the feed source reaches the main reflection panel after being reflected by the metasurface unit.

8. The reflector antenna according to claim 7, wherein: The metasurface array of the first surface includes a first metasurface unit and a second metasurface unit; the secondary reflective panel is specifically used to perform phase compensation of a first phase difference on the electromagnetic wave through the first metasurface unit, and to perform phase compensation of a second phase difference on the electromagnetic wave through the second metasurface unit; the first phase difference and the second phase difference satisfy the following formula: φ 1 + 2π×( l 1 +l 2 +l 3) / λ = φ 2 + 2π×( l 4 +l 5 +l 6) / λ ， in, φ 1 is the first phase difference, is the distance from the first metasurface unit to the feed source, is the distance from the first metasurface unit to the reflection position of the main reflection surface corresponding to the first metasurface unit, is the distance from the reflection position of the main reflection surface corresponding to the first metasurface unit to the aperture of the reflection surface antenna, is the wavelength of the electromagnetic wave, φ 2 is the second phase difference, is the distance from the second metasurface unit to the feed source, is the distance from the second metasurface unit to the reflection position of the main reflection surface corresponding to the second metasurface unit, is the distance from the reflection position of the main reflection surface corresponding to the second metasurface unit to the aperture of the reflection surface antenna.

9. A reflector antenna, characterized in that: It includes a main reflection panel and a receiving structure, wherein the receiving structure includes a receiver and a sub-reflection panel, and the distance and relative posture between the receiver and the sub-reflection panel are fixed; The main reflective panel is a spherical panel; the receiving structure is used to rotate relative to the main reflective panel around the center of the sphere on which the main reflective panel is located; the second surface of the secondary reflective panel is provided with a metasurface array; The main reflection panel is used to receive electromagnetic waves and reflect the received electromagnetic waves; The secondary reflective panel is configured to perform phase control on the electromagnetic wave reflected by the primary reflective panel through the second surface; and transmit the phase-controlled electromagnetic wave to the receiver through the second surface; The receiver is used to receive and process the electromagnetic waves sent by the secondary reflection panel.

10. The reflector antenna according to claim 9, wherein: The relative position of the main reflection panel and the center of the spherical surface where the main reflection panel is located remains unchanged, and the receiving structure is used to rotate around the center of the spherical surface where the main reflection panel is located.

11. The reflector antenna according to claim 9, wherein: The relative position of the receiving structure and the center of the spherical surface where the main reflection panel is located remains unchanged, and the main reflection panel is used to rotate around the center of the spherical surface where the main reflection panel is located.

12. The reflector antenna according to any one of claims 9 to 11, characterized in that: The second surface is a plane on the secondary reflective panel, or a curved surface on the secondary reflective panel.

13. The reflector antenna according to any one of claims 9 to 11, characterized in that: The metasurface array of the second surface includes a phase control layer, a dielectric layer and a reflective layer; The phase control layer includes a plurality of metasurface units uniformly arranged on the dielectric layer, wherein one of the metasurface units includes a metal structure; The reflective layer is used to reflect electromagnetic waves passing through the phase control layer and the dielectric layer.

14. The reflector antenna according to any one of claims 9 to 11, characterized in that: The metasurface array of the second surface includes a plurality of uniformly arranged metasurface units, each of the metasurface units includes a lattice containing liquid crystal; The liquid crystal in the lattice is used to control the phase of the electromagnetic wave reflected by the main reflection panel by applying a bias voltage, and is used to transmit the electromagnetic wave after the phase control.

15. A beam steering method, applied to a reflector antenna, characterized in that: The reflector antenna comprises a main reflector panel and a feed structure, wherein the feed structure comprises a feed source and a sub-reflector panel, and the distance and relative posture between the feed source and the sub-reflector panel are fixed; The main reflective panel is a spherical panel; the feed structure is used to rotate relative to the main reflective panel around the center of the sphere on which the main reflective panel is located; the first surface of the secondary reflective panel is covered with a metasurface array; The method comprises: generating electromagnetic waves by the feed source; Sending the electromagnetic wave generated by the feed source to the first surface of the secondary reflector panel, and performing phase control on the electromagnetic wave generated by the feed source through the first surface; sending the phase-controlled electromagnetic wave to the main reflection panel; The phase-controlled electromagnetic wave is reflected by the main reflection panel.

16. A beam steering method, applied to a reflector antenna, characterized in that: The reflector antenna includes a main reflector panel and a receiving structure, the receiving structure includes a receiver and a sub-reflector panel, and the relative positions of the receiver and the sub-reflector panel are fixed; The main reflective panel is a spherical panel; the receiving structure is used to rotate relative to the main reflective panel around the center of the sphere where the main reflective panel is located; The second surface of the secondary reflective panel is provided with a metasurface array; The method comprises: receiving electromagnetic waves transmitted to the main reflective panel, and reflecting the received electromagnetic waves via the main reflective panel; performing phase control on the electromagnetic waves reflected by the main reflection panel through the second surface; sending the phase-controlled electromagnetic wave to the receiver; The phase-modulated electromagnetic wave is received and processed by the receiver.

17. A communication device, characterized in that: The communication device includes the reflector antenna according to any one of claims 1 to 8 and / or the reflector antenna according to any one of claims 9 to 14.

Images