Antenna unit and antenna array

Abstract

The present application provides an antenna unit and an antenna array. The antenna unit comprises a dielectric layer, a radiating layer, and a phase-shifting layer which are arranged in a stack, the dielectric layer being located between the radiating layer and the phase-shifting layer; a metallic radiator comprised in the radiating layer has a mono-symmetric structure; the phase-shifting layer has a first operating mode and a second operating mode; in the first operating mode, a radio frequency current of the phase-shifting layer has a first direction, and the phase-shifting layer is used for performing phase control on a first electromagnetic wave received by the antenna unit by means of the radiating layer to obtain a second electromagnetic wave; and in the second operating mode, the radio frequency current of the phase-shifting layer has a second direction, and the phase-shifting layer is used for performing phase control on the first electromagnetic wave to obtain a third electromagnetic wave, the first direction being different from the second direction, and the phase of the second electromagnetic wave being different from the phase of the third electromagnetic wave. The present application is conducive to increasing the phase shift bandwidth of the antenna unit, improving the in-band phase difference consistency of the antenna unit, reducing phase difference errors, and enhancing the radiation efficiency of the antenna unit.

Description

An antenna element and an antenna array

[0001] This application claims priority to Chinese Patent Application No. 202411786217.X, filed on December 4, 2024, entitled "An Antenna Element and Antenna Array", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of antenna technology, and more specifically, to an antenna element and an antenna array. Background Technology

[0003] Terahertz (THz) reconfigurable intelligent surfaces (RIS) are metasurface structures with dynamic adjustment capabilities, capable of adjusting their electromagnetic properties in real time to adapt to different application requirements. Compared with traditional static metasurfaces, reconfigurable intelligent surfaces can change their structure, shape, and electromagnetic response under external excitation or control, thereby achieving real-time control of terahertz (THz) waves. Based on the needs of future communication scenarios, intelligent large-scale array devices require reconfigurable devices to have the following characteristics: (1) good tuning performance in the high-frequency band, high switching ratio, and fast control speed; (2) support for large-scale fabrication with low fabrication cost, strong compatibility with other integrated devices, and dynamic programmable control; (3) low power consumption, low insertion loss, and strong environmental stability. Summary of the Invention

[0004] This application provides an antenna element and an antenna array that achieves geometric phase effect based on the geometric phase principle, thereby improving the phase shift bandwidth of the antenna element, improving the in-band phase difference consistency of the antenna element, reducing phase difference error, and improving the radiation efficiency of the antenna element.

[0005] In a first aspect, an antenna element is provided, comprising a dielectric layer, a radiating layer, and a phase-shifting layer stacked together. The dielectric layer supports the radiating layer and the phase-shifting layer and is located between the radiating layer and the phase-shifting layer. The dielectric layer is made of a semiconductor material. The radiating layer includes a metal radiator with a single symmetric structure. The phase-shifting layer has a first operating mode and a second operating mode. In the first operating mode, the radio frequency current of the phase-shifting layer has a first direction, and the phase-shifting layer is used to phase-modulate the first electromagnetic wave received by the antenna element through the radiating layer to obtain a second electromagnetic wave. In the second operating mode, the radio frequency current of the phase-shifting layer has a second direction, and the phase-shifting layer is used to phase-modulate the first electromagnetic wave to obtain a third electromagnetic wave. The first direction is different from the second direction, and the second electromagnetic wave and the third electromagnetic wave have different phases.

[0006] Based on the above technical solution, the antenna element provided in this application, by stacking a dielectric layer, a radiating layer, and a phase-shifting layer, can achieve phase modulation of the incident electromagnetic wave by changing the direction of the radio frequency current. Furthermore, the radiating layer with a single symmetric structure can work together with the phase-shifting layer to generate interlayer electromagnetic coupling, enhancing the antenna element's polarization conversion of the incident electromagnetic wave. Compared to existing resonant metasurface element structures, the antenna element provided in this application has a larger phase-shifting bandwidth, better in-band phase difference consistency, smaller phase difference error, and higher radiation efficiency.

[0007] For example, a metallic radiator consists of one or more ring-shaped metallic units with notches.

[0008] For example, the metal radiator is composed of multiple notched, ring-shaped metal units nested together.

[0009] For example, the metal units that make up the metal radiator are circular, square, or rectangular in shape.

[0010] For example, the metal used to fabricate the antenna element is one or more of aluminum (Al), silver (Ag), gold (Au), or copper (Cu).

[0011] In conjunction with the first aspect, in some implementations of the first aspect, a first channel, a second channel, a third channel, and a fourth channel are provided on the phase-shifting layer. The first channel, the second channel, the third channel, and the fourth channel divide the metal patch on the phase-shifting layer into four parts. The first channel is annular. The second channel and the third channel both start from the outer edge of the first channel and terminate at the edge of the antenna element. The included angle between the second channel and the third channel is greater than 0. The fourth channel divides the metal patch surrounded by the first channel into two parts. The phase-shifting layer also includes a first switch disposed on the second channel and a second switch disposed on the third channel. The first switch connects to the metal patches on both sides of the second channel, and the second switch connects to the metal patches on both sides of the third channel. The first switch and the second switch are also provided with control lines respectively connected to the metal patches on both sides of the fourth channel. The metal patches on both sides of the fourth channel are connected to feed electrodes for controlling the first switch and the second switch.

[0012] Based on the above technical solution, by setting a first switch and a second switch in the phase shifting layer, the direction of the radio frequency current in the phase shifting layer can be changed by changing the on / off state of the first switch and the second switch.

[0013] For example, the first switch and the second switch are transistors. For instance, the first switch and the second switch are high electron mobility transistors or triodes.

[0014] For example, the doped materials of the first and second switches are prepared in the form of an epitaxial layer on the upper surface of the dielectric layer.

[0015] For example, the doping material is one of the following: aluminum gallium nitride (AlGaN), gallium nitride (GaN), indium gallium nitride (InGaN), aluminum gallium arsenide (AlGaAs), or gallium arsenide (GaAs).

[0016] For example, in the first operating mode, the first switch is off and the second switch is on; in the second operating mode, the second switch is off and the first switch is on.

[0017] In conjunction with the first aspect, in some implementations of the first aspect, the angle between the second channel and the third channel is 90 degrees, the angle between the first direction and the second direction is 180 degrees, and the phase difference between the second electromagnetic wave and the third electromagnetic wave is 180 degrees.

[0018] Based on the above technical solution, by setting the angle between the second channel and the third channel to 90 degrees, the direction reversal of the radio frequency current of the phase shifting layer can be achieved, thereby realizing phase modulation of the incident electromagnetic wave with a 180-degree phase difference.

[0019] For example, the second channel is rectangular, square, circular, or elliptical in shape; the third channel is rectangular, square, circular, or elliptical in shape.

[0020] The shape of the second channel may be the same as or different from that of the third channel.

[0021] For example, the metal patches surrounding the first channel and located on both sides of the fourth channel are a first metal patch and a second metal patch; the shape of the first metal patch is triangular, semi-circular or semi-elliptical; the shape of the second metal patch is triangular, semi-circular or semi-elliptical.

[0022] The shape of the second channel may be the same as or different from that of the third channel.

[0023] In a second aspect, an antenna array is provided, comprising a plurality of antenna elements as described in the first aspect above.

[0024] Based on the above technical solution, it is beneficial to realize the individual control of the antenna elements included in the antenna array, so that the different antenna elements included in the antenna array can work in the first working mode or the second working mode. This is conducive to realizing real-time two-dimensional beam scanning in the terahertz band and has important application value for the development of terahertz reconfigurable smart surface wavefront adjustment capability.

[0025] In conjunction with the second aspect, in some implementations of the second aspect, the antenna array includes M×N antenna elements as described in the first aspect above, and the M×N antenna elements are arranged in an M×N array.

[0026] In conjunction with the second aspect, in some implementations of the second aspect, in an M×N array of antenna elements, adjacent first antenna elements and second antenna elements are located in the same column, with the first antenna element located above the second antenna element. The metal patch in the phase-shifting layer of the first antenna element near its lower edge and the metal patch in the phase-shifting layer of the second antenna element near its upper edge are integrally formed. In an M×N array of antenna elements, adjacent third antenna elements and fourth antenna elements are located in the same row, with the third antenna element located to the left of the fourth antenna element. The metal patch in the phase-shifting layer of the third antenna element near its right edge and the metal patch in the phase-shifting layer of the fourth antenna element near its left edge are integrally formed.

[0027] Thirdly, a communication device is provided, comprising the antenna array described in the second aspect above. Attached Figure Description

[0028] Figure 1 is a schematic diagram of a communication system provided in an embodiment of this application.

[0029] Figure 2 shows a schematic diagram of the structure of the antenna unit provided in the embodiment of this application.

[0030] Figure 3 shows a schematic diagram of the structure of the radiation layer provided in an embodiment of this application.

[0031] Figure 4 shows a schematic diagram of the phase-shifting layer provided in an embodiment of this application.

[0032] Figure 5 shows a schematic diagram of the antenna unit provided in an embodiment of this application.

[0033] Figure 6 shows the simulation diagrams of the surface electric field distribution and surface current distribution of the antenna element provided in the embodiments of this application under different operating modes.

[0034] Figure 7 shows a schematic diagram of the antenna array provided in an embodiment of this application.

[0035] Figure 8 shows a schematic diagram of the simulation results of the amplitude and phase characteristics and phase difference of the antenna array provided in the embodiments of this application under different operating modes. Detailed Implementation

[0036] The technical solutions in this application will now be described with reference to the accompanying drawings.

[0037] The embodiments described in this application are only some embodiments, not all embodiments. All other embodiments obtained by those skilled in the art based on the descriptions of the embodiments in this application without inventive effort are within the scope of protection claimed in this application.

[0038] This application provides an antenna element that can be applied to antenna arrays, as well as to fields such as spatial light modulation of electromagnetic waves and electronically controlled two-dimensional imaging. It can also be used in base station antennas, microwave antennas, satellite communications, millimeter-wave radar, and other fields.

[0039] The antennas and / or antenna systems described in this application can be applied to various communication systems, such as: Global System for Mobile Communication (GSM), Code Division Multiple Access (CDMA), Wideband Code Division Multiple Access (WCDMA), General Packet Radio Service (GPRS), Long Term Evolution (LTE), LTE Frequency Division Duplex (FDD), LTE Time Division Duplex (TDD), Universal Mobile Telecommunication System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX), 5th Generation (5G), New Radio (NR), inter-satellite communication, and satellite communication. The antennas and / or antenna systems described in this application can also be applied to other communication systems, which will not be detailed here.

[0040] Figure 1 is a schematic diagram of a communication system provided in an embodiment of this application. As shown in Figure 1, the communication system 100 includes a network device (network device 110 as shown in Figure 1) and terminal devices (terminal devices 120-1 to 120-L as shown in Figure 1). The network device 110 and the terminal devices (terminal devices 120-1 to 120-L) can communicate via a wireless link to exchange information. It is understood that the network device and the terminal devices can also be referred to as communication devices.

[0041] Network device 110 may include at least one antenna array (antenna array 111 as shown in FIG1). As shown in FIG1, antenna array 111 may include multiple antenna elements, each antenna element may include a high-electron-mobility transistor (HEMT) device. By adjusting the voltage excitation received by the HEMT device in the antenna element, network device 110 can change the phase and amplitude of the output signal of the antenna element, thereby controlling the direction of the antenna beam to achieve communication with one or more terminal devices among terminal devices 120-1, terminal device 120-2, ..., terminal device 120-L.

[0042] In the embodiments of this application, the terminal device may also be referred to as user equipment (UE), access terminal, user unit, user station, mobile station, mobile station, remote station, remote terminal, mobile device, user terminal, terminal, wireless communication device, user agent, or user apparatus.

[0043] Terminal devices can be devices that provide voice / data, such as handheld devices with wireless connectivity, in-vehicle devices, etc. Currently, examples of terminals include: mobile phones, tablets, laptops, PDAs, mobile internet devices (MIDs), wearable devices, virtual reality (VR) devices, augmented reality (AR) devices, wireless terminals in industrial control, wireless terminals in self-driving vehicles, wireless terminals in remote medical surgery, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, cellular phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDAs), handheld devices with wireless communication capabilities, computing devices or other processing devices connected to wireless modems, wearable devices, terminal devices in 5G networks, or future public land mobile communication networks. Terminal devices in a network (PLMN), etc., are not limited to this in the embodiments of this application.

[0044] By way of example and not limitation, in this embodiment, the terminal device can also be a wearable device. Wearable devices, also known as wearable smart devices, are a general term for devices that utilize wearable technology to intelligently design and develop everyday wearables, such as glasses, gloves, watches, clothing, and shoes. Wearable devices are portable devices that are worn directly on the body or integrated into the user's clothing or accessories. Wearable devices are not merely hardware devices, but also achieve powerful functions through software support, data interaction, and cloud interaction. Broadly speaking, wearable smart devices include those that are feature-rich, large in size, and can achieve complete or partial functions without relying on a smartphone, such as smartwatches or smart glasses, as well as those that focus on a specific type of application function and require the use of other devices such as smartphones, such as various smart bracelets and smart jewelry for vital sign monitoring.

[0045] In this embodiment, the device for implementing the functions of the terminal device can be the terminal device itself, or it can be any device capable of supporting the terminal device in implementing those functions, such as a chip system. This device can be installed in or used in conjunction with the terminal device. In this embodiment, the chip system can be composed of chips or may include chips and other discrete components. This embodiment only uses the terminal device as an example to illustrate the device for implementing the functions of the terminal device, and does not constitute a limitation on the solution of this embodiment.

[0046] The network device in this application embodiment may include a device for communicating with a terminal device. For example, the network device may include an access network device or a wireless access network device, such as a base station (BS). The wireless access network device in this application embodiment may refer to a radio access network (RAN) node (or device) that connects the terminal device to the wireless network. A base station can broadly encompass, or be replaced by, various names including: NodeB, evolved NodeB (eNB), next-generation NodeB (gNB), relay station, access point, transmitting and receiving point (TRP), transmitting point (TP), master station, auxiliary station, motor slide retainer (MSR) node, home base station, network controller, access node, wireless node, access point (AP), transmission node, transceiver node, baseband unit (BBU), remote radio unit (RRU), active antenna unit (AAU), remote radio head (RRH), central unit (CU), distributed unit (DU), radio unit (RU), positioning node, etc. A base station can be a macro base station, micro base station, relay node, donor node, or similar entities, or combinations thereof. A base station can also refer to a communication module, modem, or chip installed within the aforementioned equipment or apparatus. A base station can also be a mobile switching center, a device that performs base station functions in D2D, V2X, and M2M communications, or a device that performs base station functions in future communication systems. A base station can support networks using the same or different access technologies. Optionally, a RAN node can also be a server, wearable device, vehicle, or in-vehicle equipment. For example, the access network equipment in vehicle-to-everything (V2X) technology can be a roadside unit (RSU). The embodiments of this application do not limit the specific technologies or equipment forms used in the network equipment.

[0047] Base stations can be fixed or mobile. For example, a helicopter or drone can be configured to act as a mobile base station, and one or more cells can move depending on the location of the mobile base station. In other examples, a helicopter or drone can be configured as a device to communicate with another base station.

[0048] In some deployments, the network devices mentioned in the embodiments of this application may be devices including CU, DU, or CU and DU, or devices with control plane CU nodes (central unit-control plane (CU-CP)) and user plane CU nodes (central unit-user plane (CU-UP)) and DU nodes. For example, the network devices may include gNB-CU-CP, gNB-CU-UP, and gNB-DU.

[0049] In some deployments, multiple RAN nodes collaborate to assist terminals in achieving wireless access, with different RAN nodes each implementing some of the base station's functions. For example, RAN nodes can be CUs, DUs, CU-CPs, CU-UPs, or RUs. CUs and DUs can be configured separately or included in the same network element, such as a BBU. RUs can be included in radio frequency equipment or radio frequency units, such as RRUs, AAUs, or RRHs.

[0050] RAN nodes can support one or more types of fronthaul interfaces, each corresponding to a DU and RU with different functions. If the fronthaul interface between the DU and RU is a common public radio interface (CPRI), the DU is configured to implement one or more baseband functions, and the RU is configured to implement one or more radio frequency functions. If the fronthaul interface between the DU and RU is another type of interface, relative to CPRI, some downlink and / or uplink baseband functions, such as, for downlink, precoding, digital beamforming (BF), or one or more of inverse fast Fourier transform (IFFT) / cyclic prefix addition (CP), are moved from the DU to the RU; and for uplink, digital beamforming (BF), or one or more of fast Fourier transform (FFT) / cyclic prefix removal (CP), are moved from the DU to the RU. In one possible implementation, the interface can be an enhanced common public radio interface (eCPRI). Under the eCPRI architecture, the segmentation between DU and RU differs, corresponding to different categories (Cat) of eCPRI, such as eCPRI Cat A, B, C, D, E, F.

[0051] Taking eCPRI Cat A as an example, for downlink transmission, the DU is configured to implement one or more functions before and after layer mapping (i.e., coding, rate matching, scrambling, modulation, and layer mapping), while other functions after layer mapping (e.g., RE mapping, digital beamforming (BF), or one or more functions of inverse fast Fourier transform (IFFT) / adding cyclic prefix (CP)) are moved to the RU. For uplink transmission, the DU is configured to implement one or more functions before and after de-RE mapping (i.e., decoding, de-rate matching, descrambling, demodulation, inverse discrete Fourier transform (IDFT), channel equalization, and de-RE mapping), while other functions after de-RE mapping (e.g., digital BF or one or more functions of fast Fourier transform (FFT) / removing CP) are moved to the RU. It is understandable that the functional descriptions of the DU and RU corresponding to various types of eCPRI can be found in the eCPRI protocol, and will not be elaborated here.

[0052] In one possible design, the processing unit in the BBU used to implement baseband functions is called the baseband high (BBH) unit, and the processing unit in the RRU / AAU / RRH used to implement baseband functions is called the baseband low (BBL) unit.

[0053] In different systems, CU (or CU-CP and CU-UP), DU, or RU may have different names, but those skilled in the art will understand their meaning. For example, in an open RAN (ORAN) system, CU can also be called O-CU (open CU), DU can also be called O-DU, CU-CP can also be called O-CU-CP, CU-UP can also be called O-CU-UP, and RU can also be called O-RU. Any of the units among CU (or CU-CP, CU-UP), DU, and RU in this application can be implemented through software modules, hardware modules, or a combination of software modules and hardware modules.

[0054] Network devices and / or terminal devices can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; they can also be deployed on water; and they can also be deployed in the air on airplanes, balloons, and satellites. This application does not limit the scenario in which the network devices and terminal devices are located. Furthermore, terminal devices and network devices can be hardware devices, or software functions running on dedicated hardware or general-purpose hardware, such as virtualization functions instantiated on a platform (e.g., a cloud platform), or entities that include dedicated or general-purpose hardware devices and software functions. This application does not limit the specific form of the terminal devices and network devices.

[0055] Terahertz (THz) reconfigurable intelligent surfaces (RIS) are metasurface structures with dynamic adjustment capabilities, capable of adjusting their electromagnetic properties in real time to adapt to different application requirements. Compared to traditional static metasurfaces, reconfigurable intelligent surfaces can change their structure, shape, and electromagnetic response under external excitation or control, thereby achieving real-time control of terahertz (THz) waves. Based on the needs of future communication scenarios, intelligent large-scale array devices (such as massive multiple-input multiple-output (MIMO) RIS) require reconfigurable devices to have the following characteristics:

[0056] (1) It has good tuning performance in the high-frequency band, high switching ratio, and fast control speed;

[0057] (2) It supports large-scale fabrication with low fabrication cost, strong compatibility with other integrated devices, and can be dynamically programmed and controlled.

[0058] (3) Low power consumption, low insertion loss and strong environmental stability.

[0059] Existing RIS architectures based on HEMT switches suffer from problems such as narrow bandwidth and poor phase shift consistency.

[0060] In view of this, embodiments of this application provide an antenna element and an antenna array, aiming to broaden the phase shift bandwidth of the reconfigurable smart surface and improve phase shift consistency by combining the geometric phase principle with the terahertz reconfigurable smart surface structure.

[0061] This application provides an antenna element and antenna array that can be applied to future communication systems and scenarios such as integrated sensing and communication. The antenna element and antenna array provided in this application can be used for beam control in the millimeter-wave and terahertz bands, including beamforming, beam scanning, and beam deflection. Besides beam control, this reconfigurable array antenna can also be used in programmable holographic imaging systems, adaptive intelligent sensing, and new wireless communication systems.

[0062] The antenna element and antenna array provided in the embodiments of this application will be described in detail below.

[0063] Referring to Figure 2, Figure 2 shows a schematic diagram of an antenna unit provided in an embodiment of this application.

[0064] As shown in Figure 2, the antenna unit includes a three-layer structure arranged in a stacked manner: a dielectric layer 220, a radiating layer 210 disposed on a first surface of the dielectric layer 220 (e.g., the upper surface of the dielectric layer 220 in Figure 2), and a phase-shifting layer 230 disposed on a second surface of the dielectric layer 220 (e.g., the lower surface of the dielectric layer 220 in Figure 2). The second surface of the dielectric layer 220 is opposite to the first surface.

[0065] The following is a detailed description of the three-layer structure.

[0066] (1) Dielectric layer 220.

[0067] The dielectric layer 220 can also be called a dielectric substrate, dielectric substrate, or phase-shifting resonant layer dielectric substrate. The dielectric layer 220 is located between the radiation layer 210 and the phase-shifting layer 230 and is used to support the radiation layer 210 and the phase-shifting layer 230.

[0068] The dielectric layer 220 supports the radiation layer 210 and the phase-shifting layer 230. It can be understood that the dielectric layer 220 can serve as a processing carrier for the metal patterns of the radiation layer 210 and the phase-shifting layer 230. For example, the radiation layer 210 and the phase-shifting layer 230 can be respectively formed on the two surfaces of the dielectric layer 220 by means of a metal coating.

[0069] It is understood that the dielectric layer 220 serves as a support carrier for the radiation layer 210 and the phase-shifting layer 230, and is not a structural layer that affects the function of the structure. Therefore, it can be replaced with any structure that can function as a support carrier. This application does not limit this.

[0070] For example, the dielectric layer 220 can be a semiconductor material. For example, sapphire, high-resistivity silicon, indium phosphide (InP), gallium arsenide (GaAs), or silicon carbide (SiC), etc., are not limited to this embodiment of the application.

[0071] (2) Radiation layer 210.

[0072] The radiating layer 210 is used to realize the radiation function and to work together with the phase-shifting layer 230 to generate interlayer electromagnetic coupling and enhance the polarization conversion of the antenna element to electromagnetic waves.

[0073] For example, the radiation layer 210 includes a metallic radiator with a single symmetric structure; in other words, the radiation layer 210 has a single symmetric structure. The metallic radiator may also be referred to as a metallic pattern, a metallic coating, etc., and this application does not limit it to these terms.

[0074] It should be understood that when the metal radiator included in the radiating layer 210 has a single symmetric structure, polarization conversion of the electromagnetic waves received by the antenna element through the radiating layer 210 can be achieved.

[0075] Optionally, the axis of symmetry of the metallic radiator can be the x-axis, y-axis, or other directions, and this application does not limit this.

[0076] Optionally, the metallic radiator is composed of one or more metallic units, the combination of which has a single symmetric structure.

[0077] Optionally, one or more metal units constituting the metal radiator are notched, ring-shaped metal units.

[0078] Optionally, the metal radiator is composed of multiple notched, ring-shaped metal units nested together.

[0079] Optionally, the notched, annular metal unit can be in the form of a circle, square, rectangle, ellipse, semicircle, semi-ellipse, triangle, or other shapes with a single symmetric structure.

[0080] Optionally, the metallic radiator is composed of multiple metallic units, in which case any two metallic units can be the same or different.

[0081] Optionally, the material of the metal radiator may be one or more of gold (Au), aluminum (Al), silver (Ag) or copper (Cu).

[0082] Referring to Figure 3, Figure 3 shows a schematic diagram of the structure of the radiation layer 210 provided in the embodiment of this application.

[0083] As shown in Figure 3(a), the metal radiator included in the radiation layer 210 is composed of a square metal unit with a notch.

[0084] As shown in Figure 3(b) or (c), the metal radiator included in the radiation layer 210 is composed of a square ring-shaped metal unit with a notch. As can be seen from the figure, the axis of symmetry of the metal radiator shown in Figure 3(b) is the y-axis, and the axis of symmetry of the metal radiator shown in Figure 3(c) has an angle with the x-axis.

[0085] As shown in Figure 3(d), the metal radiator included in the radiation layer 210 is composed of two nested, square ring-shaped metal units with gaps. As can be seen from the figure, the two metal units constituting the metal radiator shown in Figure 3(d) have the same shape.

[0086] As shown in Figure 3(e), the radiating layer 210 includes a metallic radiator composed of two nested, notched annular metallic units. As can be seen from the figure, the two metallic units constituting the metallic radiator shown in Figure 3(e) are different; the outer metallic unit is circular in shape, while the inner metallic unit is square in shape.

[0087] As shown in Figure 3(f), the radiating layer 210 includes a metallic radiator composed of two nested metallic units. As can be seen from the figure, the two metallic units that make up the metallic radiator shown in Figure 3(f) have different shapes. The outer metallic unit is a circular ring-shaped metallic unit with a notch, and the inner metallic unit is a square metallic unit with a notch.

[0088] The shape and arrangement of the metal units constituting the radiation layer 210 shown in Figure 3 are merely examples and do not limit the embodiments of this application.

[0089] (3) Phase shift layer 230.

[0090] The phase-shifting layer 230 has two operating modes, for example, a first operating mode and a second operating mode.

[0091] In the first operating mode, the radio frequency current of the phase-shifting layer 230 has a first direction, and the phase-shifting layer 230 is used to phase-modulate the first electromagnetic wave received by the antenna element through the radiating layer 210 to obtain a second electromagnetic wave. In the second operating mode, the radio frequency current of the phase-shifting layer 230 has a second direction, and is used to phase-modulate the first electromagnetic wave received by the antenna element through the radiating layer 210 to obtain a third electromagnetic wave. The first direction is different from the second direction, and the second electromagnetic wave and the third electromagnetic wave have different phases.

[0092] In other words, the antenna element provided in this application can achieve phase modulation and polarization conversion of the incident electromagnetic wave of the antenna element by changing the direction of the radio frequency current of the phase shift layer 230 in different operating modes.

[0093] In one possible implementation, a first channel, a second channel, a third channel, and a fourth channel are provided on the phase-shifting layer 230, which divide the metal patch on the phase-shifting layer 230 into four parts.

[0094] The first channel is annular. For example, the first channel can be a square annular, a circular annular, a rectangular annular, or an elliptical annular, etc.

[0095] Optionally, the shape of the inner side of the first channel can be the same as or different from the shape of the outer side of the first channel. For example, the outer side of the first channel can be square, and the inner side of the first channel can be circular.

[0096] The second and third channels both start at the outer edge of the first channel and end at the edge of the antenna element, and the angle between the second and third channels is greater than 0.

[0097] Optionally, the angle between the second and third channels is 90 degrees.

[0098] Based on the above technical solution, when the angle between the second and third channels is 90 degrees, and the switches in the second and third channels are alternately turned on, the flow path of the radio frequency current in the phase shift layer 230 rotates by 90 degrees, which is equivalent to a 90-degree rotation of the antenna element structure. According to the geometric phase principle, the cross-polarization scattering phase of the antenna element undergoes a 180-degree phase shift. Furthermore, based on the single symmetry of the metallic radiator included in the radiating layer 210, the radiating layer 210 and the phase shift layer 230 generate interlayer electromagnetic coupling, which enhances the resonant response of the antenna element to cross-polarized waves and increases the scattering amplitude of the cross-polarized waves.

[0099] Optionally, the second channel can be rectangular, square, circular, or elliptical in shape.

[0100] Optionally, the third channel can be rectangular, square, circular, or elliptical in shape.

[0101] Optionally, the shape of the second or third channel can be other irregular shapes.

[0102] Optionally, the shape of the second channel is the same as that of the third channel.

[0103] Optionally, the second channel has the same shape as the third channel, and the dimensions of the second channel are the same as those of the third channel. For example, if both the second and third channels are rectangular, then the width of the second channel is the same as the width of the third channel.

[0104] The fourth channel divides the metal patch surrounded by the first channel into two parts. In other words, the fourth channel starts at the inner edge of the first channel and ends at the inner edge of the first channel.

[0105] The metal patches surrounding the first groove and located on both sides of the fourth groove are the first metal patch and the second metal patch.

[0106] Optionally, the first metal patch may be triangular, semi-circular, semi-elliptical, or other shapes.

[0107] Optionally, the second metal patch can be triangular, semi-circular, semi-elliptical, or other shapes.

[0108] The shape of the first metal patch and the shape of the second metal patch may be the same or different, and this application does not limit this.

[0109] It is understandable that, since the first and second metal patches are located within the first channel and on either side of the fourth channel, their shapes are related to the shapes of the first and fourth channels. For example, if the inner side of the first channel is a square or rectangle, and the fourth channel is a square or rectangle, then the shapes of the first and second metal patches are triangular. Or, for another example, if the inner side of the first channel is a circle, and the fourth channel is a square or rectangle, then the shapes of the first and second metal patches are semi-circular.

[0110] The phase-shifting layer 230 also includes a first switch disposed in the second channel and a second switch disposed in the third channel. The first switch is connected to metal patches on both sides of the second channel, and the second switch is connected to metal patches on both sides of the third channel. The first and second switches are also provided with control lines respectively connected to metal patches on both sides of a fourth channel (i.e., the first and second metal patches). The metal patches on both sides of the fourth channel are connected to feed electrodes used to control the first and second switches. The feed electrodes are used to generate different voltages to control the opening and closing of the first switch.

[0111] Optionally, in the first operating mode, the first switch is open and the second switch is closed. In the second operating mode, the first switch is closed and the second switch is open.

[0112] Optionally, the first and second switches are transistors. For example, the first and second switches can be HEMT switches, field-effect transistors (FETs), phase-change materials, or bipolar junction transistors. The first and second switches can also be referred to as voltage-controlled switching transistors.

[0113] Optionally, the doped materials for the first and second switches are prepared in the form of an epitaxial layer on the upper surface of the dielectric layer 220.

[0114] Optionally, the doping material is one of the following: aluminum gallium nitride (AlGaN), gallium nitride (GaN), indium gallium nitride (InGaN), aluminum gallium arsenide (AlGaAs), or gallium arsenide (GaAs).

[0115] For example, the first switch is configured on the phase-shifting layer 230 as follows: First, a doped material is generated on the dielectric layer 220 in the form of an epitaxial layer, and an active region is isolated in a designated area by ion implantation. Then, the ohmic contacts of the source and drain of the first switch are set on the active region to realize the transistor conduction state. Then, metal patches 411 and 412 are overlaid on the epitaxial layer and the ohmic contacts in a metal patterning manner. The ohmic contact layer of the source and the ohmic contact layer of the drain are covered between the oscillation structure of the phase-shifting layer 230 (i.e., metal patches 411 and 412) and the metal pads. The metal pads on both sides and the covered ohmic contact layer constitute the source and drain of the first switch. The source and drain of the first switch are grounded through the cathode leads connected by metal patches 411 and 412. Between the two metal pads, a Schottky contact for the gate of the first switch is made at a position equidistant from the two metal pads. The gate of the first switch is connected to the anode of the metal patch 407 through a gate metal connection line 405. The anode is connected to an independent electrode for power feeding.

[0116] Optionally, the metal patch on the phase-shifting layer 230 may be made of one or more of gold (Au), aluminum (Al), silver (Ag), or copper (Cu).

[0117] Referring to Figure 4, Figure 4 shows a schematic diagram of the structure of the phase-shifting layer 230 provided in an embodiment of this application.

[0118] As shown in Figure 4, the first channel 409, the second channel 401, the third channel 402 and the fourth channel 410 disposed on the phase shift layer 230 divide the metal patch on the phase shift layer 230 into four parts, namely the first metal patch 407, the second metal patch 408, the C-shaped metal patch 412 and the W-shaped metal patch 411 as shown in Figure 4.

[0119] As shown in Figure 4(a), the first channel 409 is a square annular channel. The second channel 401 and the third channel 402 are both rectangular, and their widths are the same. The included angle between the second channel 401 and the third channel 402 is 90 degrees. The fourth channel 410 is rectangular. Based on the shapes of the first channel 409 and the fourth channel 410, the first metal patch 407 and the second metal patch 408 shown in Figure 4(a) are triangular in shape.

[0120] As shown in Figure 4(b), the outer side of the first channel 409 is square, and the inner side is circular. The second channel 401 and the third channel 402 are both rectangular, and their widths are the same. The fourth channel 410 is rectangular. Based on the shapes of the first channel 409 and the fourth channel 410, the first metal patch 407 and the second metal patch 408 shown in Figure 4(b) are semi-circular.

[0121] As shown in Figure 4, the phase-shifting layer 230 also includes a first switch 403 disposed in the second channel 401 and a second switch 404 disposed in the third channel 402. The first switch 403 is provided with a control line 405 connected to the first metal patch 407, and the second switch 404 is provided with a control line 406 connected to the second metal patch 408.

[0122] It is understood that the shapes and sizes of the various channels or metal patches disposed on the phase shift layer 230 shown in Figure 4 are merely examples and do not limit the embodiments of this application.

[0123] It should also be understood that the above example, which describes dividing the metal patch on the phase shift layer 230 into four parts by providing the first to fourth channels on the phase shift layer 230, is not limited in this application. For example, the metal patch on the phase shift layer 230 can be divided into four parts by other means or insulating materials, so that the four parts of the metal patch on the phase shift layer 230 are mutually insulated.

[0124] Based on the above technical solution, the antenna element provided in this application, by stacking a dielectric layer, a radiating layer, and a phase-shifting layer, can achieve phase modulation of the incident electromagnetic wave by changing the direction of the radio frequency current. Furthermore, the radiating layer with a single symmetric structure can work together with the phase-shifting layer to generate interlayer electromagnetic coupling, enhancing the antenna element's polarization conversion of the incident electromagnetic wave. Compared to existing resonant metasurface element structures, the antenna element provided in this application has a larger phase-shifting bandwidth, better in-band phase difference consistency, smaller phase difference error, and higher radiation efficiency.

[0125] The foregoing description includes the dielectric layer 220, radiating layer 210, and phase-shifting layer 230 in the antenna unit provided in the embodiments of this application. However, this application does not limit the antenna unit to include only the aforementioned dielectric layer 220, radiating layer 210, and phase-shifting layer 230. It should be noted that, in actual implementation, the antenna unit provided in the embodiments of this application may also include an adapter layer 240 and a printed circuit board (PCB) layer 250.

[0126] Referring to Figure 5, Figure 5 shows a schematic diagram of an antenna element provided in an embodiment of this application.

[0127] As shown in Figure 5, in addition to the dielectric layer 220, the radiating layer 210 and the phase shifting layer 230, the antenna unit also includes a transition layer 240 and a PCB layer 250.

[0128] The transition layer 240 is used to connect the phase shift layer 230 to the PCB layer 250. The PCB layer is used to implement the layout and fabrication of control lines.

[0129] The transition layer 240 includes two first metal balls 241, a transition layer dielectric substrate 242, two metal vias 243 disposed in the transition layer dielectric substrate 242, two second metal balls 244, and two metal patches 245. The two first metal balls 241 are electrically connected to the first and second metal patches in the phase-shifting layer 230, respectively. The two first metal balls 241 are connected to the two second metal balls 244 through the two metal vias 243 and the two metal patches 245, respectively. The two second metal balls 244 are connected to the feed electrodes in the PCB layer 250 used to control the first and second switches.

[0130] PCB layer 250 consists of a PCB substrate and metal lines.

[0131] Optionally, the dielectric substrate 242 of the transition layer is made of one of the following materials: quartz, high-resistivity silicon, or SiC.

[0132] Optionally, the metal used to fabricate the antenna element may be one or more of Al, Ag, Au, or Cu.

[0133] Based on the above technical solutions, the antenna unit provided in this application optimizes the difficult planar routing into a mature multi-layer PCB routing through bottom electrode flip-chip, through-glass via (TGV) connection, and PCB redistribution layer (RDL) rerouting, thereby facilitating independent control of the antenna unit. Furthermore, based on the antenna unit provided in this application, it is advantageous to achieve a more ideal scattering coefficient and phase bandwidth, and reduce the influence of multi-layer dielectric standing wave resonance, by adjusting various structural parameters of the antenna unit and designing the metal shielding layer of the adapter board.

[0134] When the antenna element operates in different operating modes, its structure exhibits different resonant responses. Referring to Figure 6, Figure 6 shows simulation diagrams of the surface electric field distribution and surface current distribution of the antenna element provided in this embodiment under different operating modes. As shown in Figure 6, in the first operating mode (i.e., state 1 shown in Figure 6), the first switch 403 is open, and the second switch 404 is closed. In the second operating mode (i.e., state 0 shown in Figure 6), the first switch 403 is closed, and the second switch 404 is open. As can be seen from Figure 6, the antenna element provided in this application can cause the path of the radio frequency current to rotate by switching operating modes, thereby controlling the phase shift response of the structure according to the geometric phase principle.

[0135] This application also provides an antenna array comprising a plurality of antenna elements as described above. The antenna array provided in this application may also be referred to as a reconfigurable smart surface.

[0136] Optionally, the antenna array includes multiple antenna elements of the same size, and all of the antenna elements are square.

[0137] Optionally, the antenna array comprises M×N antenna elements, which are arranged in an M×N array. M and N are both integers greater than 1.

[0138] Optional, M equals N.

[0139] Optionally, in the M×N antenna elements, the first antenna element and the second antenna element are located in the same column, and the first antenna element is located above the second antenna element. The metal patch in the phase shifting layer of the first antenna element near the lower edge of the first antenna element and the metal patch in the phase shifting layer of the second antenna element near the upper edge of the second antenna element are a whole.

[0140] Optionally, in an M×N array of antenna elements, adjacent third and fourth antenna elements are located in the same row, with the third antenna element located to the left of the fourth antenna element. The metal patch in the phase-shifting layer of the third antenna element near the right edge of the third antenna element and the metal patch in the phase-shifting layer of the fourth antenna element near the left edge of the fourth antenna element are integrated into one unit.

[0141] Referring to Figure 7, Figure 7 shows a schematic diagram of the antenna array structure provided in an embodiment of this application. In Figure 7(a), the front view of the antenna array is shown, and in Figure 7(b), the rear view of the antenna array is shown. As shown in Figure 7, the antenna array includes 16 antenna elements, which are arranged orthogonally.

[0142] Taking the first and second switches of the antenna unit as HEMT switches as an example, the working principle of the antenna array provided in this application is as follows: by controlling the carrier concentration of the two-dimensional electron gas layer formed by the doped material at the position of the oscillation structure through the voltage difference between the external positive electrode and the external negative electrode, the on / off adjustment of the first and second switches is realized, thereby performing phase modulation of the incident electromagnetic wave.

[0143] Based on the above technical solution, this application combines artificial microstructures with transistors to form a terahertz independently electrically controlled reflective reconfigurable antenna unit. A reconfigurable smart surface is formed through two-dimensional planar arrangement. Based on the geometric phase principle, the path of the radio frequency current is changed by alternately controlling the conduction of transistors, further generating an equivalent structural rotation, achieving 180-degree phase control capability for high-frequency terahertz waves. Furthermore, the use of bottom electrode flip-chip, TGV conversion, and PCB RDL rewiring processes enables the wiring and independent control of a large-scale geometric phase array. The antenna array provided in this application can achieve fast, real-time, and precise two-dimensional beam scanning in the terahertz band, which has significant application value for the development of wavefront adjustment capabilities for terahertz reconfigurable smart surfaces.

[0144] Referring to Figure 8, Figure 8 shows a schematic diagram of the simulation results of the amplitude and phase characteristics and phase difference of the antenna array provided in the embodiments of this application under different operating modes. As shown in Figure 8, by changing the electromagnetic characteristics of the first and second switches by applying an external voltage, the on / off state of the first and second switches can be switched. By switching the operating modes of each antenna element included in the antenna array, phase modulation of the terahertz beam is finally achieved. As shown in Figure 8, in both operating modes, the cross-polarized wave has a 180-degree phase difference with an error of less than 2 degrees in the 122GHz to 160GHz frequency band. The cross-polarized wave reflection amplitude is highly consistent in both operating modes throughout the entire frequency band, with the maximum reflection amplitude being -6.13dB, achieving broadband and efficient modulation.

[0145] This application also provides a communication device, including the antenna array described above.

[0146] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An antenna unit, characterized by include: A dielectric layer, a radiating layer, and a phase-shifting layer are stacked together, wherein the dielectric layer supports the radiating layer and the phase-shifting layer, and the dielectric layer is located between the radiating layer and the phase-shifting layer; The dielectric layer is made of a semiconductor material; The radiation layer includes a metallic radiator, which has a single symmetric structure. The phase-shifting layer has a first operating mode and a second operating mode. In the first operating mode, the radio frequency current of the phase-shifting layer has a first direction. The phase-shifting layer is used to perform phase modulation on the first electromagnetic wave received by the antenna unit through the radiation layer to obtain the second electromagnetic wave. In the second operating mode, the radio frequency current of the phase-shifting layer has a second direction, and the phase-shifting layer is used to perform phase modulation on the first electromagnetic wave to obtain a third electromagnetic wave. The first direction is different from the second direction, and the second electromagnetic wave is different from the third electromagnetic wave.

2. The antenna unit of claim 1, wherein, The phase-shifting layer is provided with a first channel, a second channel, a third channel and a fourth channel, which divide the metal patch on the phase-shifting layer into four parts; The first channel is annular; Both the second channel and the third channel start at the outer edge of the first channel and end at the edge of the antenna element, and the angle between the second channel and the third channel is greater than 0. The fourth channel divides the metal patch surrounded by the first channel into two parts. The phase-shifting layer further includes a first switch disposed in the second channel and a second switch disposed in the third channel. The first switch is connected to metal patches on both sides of the second channel, and the second switch is connected to metal patches on both sides of the third channel. The first switch and the second switch are also provided with control lines respectively connected to metal patches on both sides of the fourth channel. The metal patches on both sides of the fourth channel are connected to feed electrodes for controlling the first switch and the second switch.

3. The antenna element according to claim 2, characterized in that, In the first operating mode, the first switch is open and the second switch is on; In the second operating mode, the second switch is off and the first switch is on.

4. The antenna unit according to claim 2 or 3, c h a r a c t e r i z e d b y The angle between the second channel and the third channel is 90 degrees, the angle between the first direction and the second direction is 180 degrees, and the phase difference between the second electromagnetic wave and the third electromagnetic wave is 180 degrees.

5. The antenna unit of any one of claims 2 to 4, wherein, The first switch and the second switch are transistors.

6. The antenna unit of any one of claims 2 to 5, wherein, The doped materials of the first switch and the second switch are prepared in the form of an epitaxial layer on the upper surface of the dielectric layer.

7. The antenna unit of claim 6, wherein, The doping material is one of the following: AlGaN, GaN, InGaN, AlGaAs, or GaAs.

8. The antenna element according to any one of claims 2 to 7, characterized in that, The second channel can be rectangular, square, circular, or elliptical in shape; The third channel can be rectangular, square, circular, or elliptical in shape.

9. The antenna unit of any one of claims 2 to 8, characterized by The metal patches surrounding the first channel and located on both sides of the fourth channel are the first metal patch and the second metal patch; The shape of the first metal patch is triangular, semi-circular, or semi-elliptical; The second metal patch is triangular, semi-circular, or semi-elliptical in shape.

10. The antenna unit of any one of claims 1 to 9, wherein, The metal radiator is composed of one or more ring-shaped metal units with notches.

11. The antenna unit of claim 10, wherein, The metal radiator is composed of multiple notched, ring-shaped metal units, which are nested together.

12. The antenna unit according to claim 10 or 11, characterized by The metal units that make up the metal radiator are circular, square, or rectangular in shape.

13. The antenna unit of any one of claims 1 to 12, wherein, The metal used to fabricate the antenna element is one or more of Al, Ag, Au, or Cu.

14. An antenna array, characterized by It includes multiple antenna elements as described in any one of claims 1 to 13.

15. The antenna array of claim 14, wherein, The antenna array includes M×N antenna elements, which are arranged in an M×N array, where M and N are both integers greater than 1.

16. The antenna array of claim 15, wherein, In the M×N antenna elements, the first antenna element and the second antenna element are located in the same column, and the first antenna element is located above the second antenna element. The metal patch in the phase shifting layer of the first antenna element near the lower edge of the first antenna element and the metal patch in the phase shifting layer of the second antenna element near the upper edge of the second antenna element are a whole. In the M×N antenna elements, the adjacent third antenna element and the fourth antenna element are located in the same row, and the third antenna element is located to the left of the fourth antenna element. The metal patch in the phase shifting layer of the third antenna element near the right edge of the third antenna element and the metal patch in the phase shifting layer of the fourth antenna element near the left edge of the fourth antenna element are a whole.

17. A communication device, characterized by The antenna array includes any one of claims 14 to 16.

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