Filtering antenna, antenna system, base station, and communication system

Abstract

NOT VISIBLE DUE TO STATUS OF PATENT

Description

Filter antenna, antenna feed system, base station and communication system

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of the People's Republic of China on February 8, 2024, with application number 202410178200.X and application name "A filtering antenna, antenna feed system, base station and communication system", the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present application relates to the field of communication technology, and in particular to a filtering antenna, an antenna feed system, a base station, and a communication system. Background Art

[0004] With the development of mobile communications, the usage rate of mobile terminals is increasing. Mobile cellular network coverage is crucial for mobile communications. The key to achieving this coverage is the antenna system. With the application and development of massive multiple input multiple output (Massive MIMO) technology in 5G mobile communications, the number of RF components in the antenna system has increased dramatically. To increase the capacity of RF components in the antenna system and conserve site space and antenna resources, the current field is placing higher demands on the miniaturization and integration of RF components in the antenna system. Summary of the Invention

[0005] The present application provides a filtering antenna, an antenna feed system, a base station, and a communication system, which are conducive to the miniaturization design of the antenna feed system.

[0006] In a first aspect, the present application provides a filtering antenna comprising a radiating surface, a filter, and a metal back cavity. The radiating surface comprises a dielectric substrate, a feed network, and a radiating structure. The feed network and radiating structure are disposed on the surface of the dielectric substrate, which is covered by the metal back cavity, and the filter is housed within the metal back cavity. The feed network comprises a combiner and an adapter, connected to the combiner and adapter via a conductive wire. The radiating structure comprises a feed patch, and the adapter and feed patch are connected via a conductive wire. Furthermore, the filter comprises a probe, connected to the combiner. Since the filter is connected to a feed source, the combiner can be connected to the feed source via the filter, allowing the feed network to excite electromagnetic waves, which can be radiated via the feed patch. Simultaneously, the filter can filter the electrical signal between the combiner and the feed source, thereby enabling the filter to remove interference noise from the electromagnetic waves or select the signal frequency of the electromagnetic waves. In the filtering antenna provided in the present application, the filter and radiating surface are integrated by sharing a metal back cavity, thereby reducing the size of the filtering antenna. In addition, since the filter and the radiation surface are connected through the probe and the junction in the filtering antenna, this can effectively reduce the loss of the filtering antenna, thereby helping to improve the radiation efficiency of the filtering antenna.

[0007] To improve the filter antenna's electromagnetic wave radiation efficiency, the radiating structure also includes a metasurface, which is used to adjust the electric field distribution of the radiating surface. In the filter antenna provided in this application, the electric field distribution of the radiating surface can be adjusted by adjusting the size and placement of the metasurface, thereby improving the directivity coefficient of the electromagnetic waves radiated by the feed patch and regulating the beam shape of the radiation pattern, such as the beam null position and depth.

[0008] When specifically configured, the metasurface may include multiple metasurface units arranged according to a predetermined periodic pattern. In the filtering antenna provided in this application, the arrangement pattern and shape of the metasurface units of the metasurface may be specifically configured according to the radiation requirements of the specific application scenario and are not limited thereto.

[0009] In practical applications, the radiating structure can include multiple metasurfaces, at least one of which is positioned adjacent to the feed patch to facilitate coupled power feeding between the feed patch and the metasurface. Furthermore, the inclusion of multiple metasurfaces in the radiating structure improves the uniformity of the electric field distribution on the radiating surface, thereby improving the radiation efficiency of the radiating surface.

[0010] In addition, the radiating structure may have multiple feeding patches, and the multiple feeding patches may be located between two adjacent metasurfaces, which is beneficial for optimizing the electric field distribution on the radiating surface.

[0011] In one possible implementation of the present application, the dielectric substrate includes a first side and a second side connected to each other, wherein the length of the first side is greater than or equal to the length of the second side. The length of the first side of the dielectric substrate is greater than or equal to a wavelength of the electromagnetic wave radiated by the radiating structure. This allows the filtering antenna to have a narrow beamwidth in the direction extending from the first side and ensures that the filtering antenna has good cross-polarization discrimination. Furthermore, the dielectric substrate adopts the above-described design, so that the dimensions of the metal back cavity along the direction extending from the first side meet the filter's installation space requirements and also reduce the impact on the feed network and feed patch.

[0012] In addition, the length of the second side of the dielectric substrate is less than or equal to half the wavelength of the electromagnetic wave radiated by the radiating structure. This can make the beam width of the filtering antenna in the extension direction of the second side wider, ensure that the filtering antenna has good cross-polarization discrimination, and facilitate the arraying of the filtering antenna along the extension direction of the second side.

[0013] The present application does not limit the polarization mode of the feed patch. For example, the feed patch may be an orthogonal polarization feed patch, that is, the polarization mode of the feed patch may be dual polarization.

[0014] To meet the dual-polarization requirements of the feed patch, the feeding network may include two combining points. Furthermore, the filtering antenna includes two filters, each combining point being connected to a probe of a filter, thereby connecting each combining point to a feed source. This allows the two combining points to be fed individually or simultaneously. When one of the two combining points is excited, the polarization of the feed patch is single-polarized; when both combining points are excited simultaneously, the polarization of the feed patch is dual-polarized.

[0015] In another possible implementation of the present application, the feed patch is a single-polarization feed patch, in which case the feed network may include only one combiner. This allows connection to the feed source via the single combiner, so that the polarization requirements of the feed patch are met through the single combiner alone.

[0016] In one possible implementation of the present application, the adapter is an air strip line, which can help reduce power loss of the electrical signal in the feed network. Furthermore, the length of the adapter can be greater than zero and less than or equal to one wavelength of the electromagnetic wave radiated by the radiating structure, so that the adapter can be used to modulate the phase of the electrical signal between the combining point and the feed patch.

[0017] In this application, the conductive wires connecting the adapter and the junction, as well as the conductive wires connecting the adapter and the feed patch, can also be air strip wires. This helps reduce power losses in the feed network and between the feed network and the feed patch, thereby reducing losses in electromagnetic waves radiated by the feed patch and improving the radiation efficiency of the filter antenna.

[0018] The filtering antenna provided in this application does not limit the connection method between the probe and the combining point. For example, the probe and the combining point are coupled and connected, or the probe and the combining point are connected through a conductive wire, as long as the transmission of electrical signals between the filter and the feeding network can be achieved.

[0019] In a second aspect, the present application further provides an antenna feed system comprising an amplifier, a phase shifter, and the filtering antenna of the first aspect. The amplifier is used to amplify the electromagnetic waves received or transmitted by the radiating structure, while the phase shifter is used to adjust the electromagnetic waves radiated by the radiating structure accordingly, thereby changing the electrical downtilt angle of the electromagnetic waves radiated by the radiating structure, thereby changing the radiation direction of the electromagnetic waves radiated by the radiating structure to meet the signal coverage requirements of the filtering antenna. The antenna feed system provided by the present application has a high degree of integration, which facilitates the miniaturization of the antenna feed system.

[0020] In a third aspect, the present application further provides a base station comprising a radio frequency processing unit, a baseband processing unit, and the antenna feed system of the second aspect, wherein the baseband processing unit is connected to the antenna feed system via the radio frequency processing unit. Due to the relatively small size of the antenna feed system provided in the present application, it helps conserve site space and antenna resources occupied by the antenna feed system. Furthermore, a large number of antenna feed systems can be deployed simultaneously in a base station, which helps increase the types of signals that can be radiated by the base station, thereby expanding the applicability of the base station.

[0021] In a fourth aspect, the present application further provides a communication system, the communication system comprising a terminal and the base station of the third aspect, wherein the terminal is in communication connection with the base station. The communication system provided by the present application has good communication performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG1 is an architecture diagram of a communication system provided in an embodiment of the present application;

[0023] FIG2 is a schematic diagram of an application scenario of the antenna feed system provided in an embodiment of the present application;

[0024] FIG3 is a schematic structural diagram of a conventional antenna feed system provided in an embodiment of the present application;

[0025] FIG4 is a schematic diagram of a layout of antennas and filters of the antenna feed system shown in FIG3 ;

[0026] FIG5 is a schematic structural diagram of a filtering antenna provided in an embodiment of the present application;

[0027] FIG6 is a top view of the filter antenna shown in FIG5 ;

[0028] FIG7 is another schematic structural diagram of a filtering antenna provided in an embodiment of the present application;

[0029] FIG8 is a side view of the filter shown in FIG5 ;

[0030] FIG9 is another schematic structural diagram of a filtering antenna provided in an embodiment of the present application;

[0031] FIG10 is a schematic structural diagram of an antenna feed system provided in an embodiment of the present application.

[0032] Figures: 1000 - base station; 2000 - terminal; 100 - antenna feed system; 10 - radome; 20 - antenna connector; 30 - antenna; 3001 - radiating element; 3002 - reflector; 40 - filter; 4001 - probe; 50 - amplifier; 60 - phase shifter; 70 - signal processing module; 80 - RF front-end circuit board; 1 - radiating surface; 101 - dielectric substrate; 1011 - first side; 1012 - second side; 102 - feed network; 1021 - combining point; 1022 - adapter; 103 - radiating structure; 1031 - feed patch; 1032 - metasurface; 10321 - metasurface unit; 104 - conductive line; 105 - metal back cavity; 1051 - bottom plate; 1052 - side plate; 200-support frame; 300-RF processing unit; 400-baseband unit; 500-connecting wires; 600-adjustment bracket; 700-grounding device. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings. However, the example embodiments can be implemented in various forms and should not be understood as being limited to the embodiments set forth herein. The same figure marks in the figures represent the same or similar structures, and thus their repeated description will be omitted. The words expressing position and direction described in the embodiments of the present application are all explained with reference to the accompanying drawings as examples, but changes can be made as needed, and the changes made are all included in the scope of protection of the present application. The drawings in the embodiments of the present application are only used to illustrate the relative position relationship and do not represent the true proportion.

[0034] It should be noted that the following description sets forth specific details to facilitate understanding of the present application. However, the present application can be implemented in a variety of other ways than those described herein, and those skilled in the art may make similar generalizations without violating the scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0035] In order to facilitate the understanding of the filtering antenna, antenna feed system and base station provided in the present application, the application scenarios are first introduced below. Figure 1 exemplarily shows an architectural diagram of a communication system to which an embodiment of the present application is applicable. As shown in Figure 1, the communication system architecture may include a base station 1000 and a terminal 2000. Wireless communication can be achieved between the base station 1000 and the terminal 2000. The base station 1000 can also be called an access network device or an access node, which can be located in a base station subsystem (BBS), a terrestrial radio access network (UMTS terrestrial radio access network, UTRAN) or an evolved universal terrestrial radio access (E-UTRAN), and is used to provide signal cell coverage to achieve communication between the terminal device and the wireless network. Specifically, the base station 1000 can be a base transceiver station (BTS) in a global system for mobile communication (GSM) or a code division multiple access (CDMA) system, a node B (NB) in a wideband code division multiple access (WCDMA) system, an evolutionary node B (eNB or eNodeB) in a long term evolution (LTE) system, a transmission reception point (TRP), a next generation NodeB (gNB) in a 5G mobile communication system, a next generation base station in a sixth generation (6G) mobile communication system, an access network device or a module of an access network device in an open access network (ORAN) system, a base station in a future mobile communication system, or an access node in a WiFi system, etc. The base station may be a centralized unit (CU), a distributed unit (DU), a CU-control plane (CP), a CU-user plane (UP), or a radio unit (RU) as described below.Among them, in the ORAN system, CU can also be called O-CU, DU can also be called open (open, O)-DU, CU-CP can also be called O-CU-CP, CU-UP can also be called O-CUP-UP, and RU can also be called O-RU. The base station 1000 of the present application can be a macro base station, a micro base station or an indoor station, a relay node or a donor node, or it can also be a wireless controller in a cloud radio access network (CRAN) scenario. Or the base station 1000 can also be a server, a vehicle-mounted device, a wearable device, a g node (gNodeB or gNB) in a new radio (NR) system, an access network device in a future evolved network, etc. For example, the base station in the vehicle to everything (V2X) technology can be a road side unit (RSU). Multiple base stations 1000 in the communication system can be base stations of the same type or different types. The base station 1000 can communicate with the terminal 2000, or communicate with the terminal 2000 through a relay station. The terminal 2000 can communicate with multiple base stations 1000 in different access technologies.

[0036] Base station 1000 is equipped with an antenna system 100 to enable signal transmission in space. Figure 2 shows a schematic diagram of an application scenario for the antenna system 100 equipped with base station 1000 shown in Figure 1. Figure 2 illustrates the structure of a support frame 200 and the antenna system 100. The antenna system 100 includes an antenna cover 10, which is fixed to a support frame 200 such as a pole or tower via the antenna cover 10 to facilitate signal reception or transmission by the antenna system 100. The antenna cover 10 has excellent electrical electromagnetic wave penetration characteristics and mechanical properties that can withstand the influence of harsh external environments, thereby protecting the antenna system from external environmental influences.

[0037] The base station 1000 may further include a radio frequency processing unit 300 and a baseband processing unit 400. The antenna system 100 is connected to the radio frequency processing unit 300 via an antenna connector 20 located outside the antenna cover 10. The baseband processing unit 400 may be connected to the antenna system 100 via the radio frequency processing unit 300. In some embodiments, the radio frequency processing unit 300 may also be referred to as a remote radio unit (RRU), and the baseband processing unit 400 may also be referred to as a baseband unit (BBU).

[0038] The support frame 200 is fixed to the ground at a certain height, and the antenna system 100 is fixed to the support frame 200 to meet the radiation distance requirements of the antenna system 100. The antenna system 100 is removably fixed to the support frame 200 by adjusting the bracket 600, so that the antenna system 100 can receive or transmit signals. The orientation of the antenna system 100 can be adjusted in a direction perpendicular to the height of the support frame 200 by adjusting the bracket 600.

[0039] In one possible embodiment, as shown in FIG2 , the RF processing unit 300 may be integrated with the antenna system 100, and the baseband processing unit 400 may be located at the remote end of the antenna system 100. In this case, the RF processing unit 300 and the antenna system 100 may be collectively referred to as an active antenna unit (AAU). It should be noted that FIG2 is only an example of the positional relationship between the RF processing unit 300 and the antenna system 100. In other embodiments, the RF processing unit 300 and the baseband processing unit 400 may also be located at the remote end of the antenna system 100. The RF processing unit 300 and the baseband processing unit 400 may be connected via a connecting wire 500.

[0040] A grounding device 700 is provided between the baseband processing unit 400 and the connecting wire 500. The grounding device 700 generally comprises a grounding electrode buried underground. A seal may be provided at the connection between the antenna feed system 100 and the connecting wire 500, and a seal may also be provided at the connection between the grounding device 700 and the connecting wire 500. Specifically, the seal may comprise at least one of insulating sealing tape and polyvinyl chloride (PVC) insulating tape. Of course, the seal may also be of other structures and is not limited to tape.

[0041] Furthermore, Figure 3 is a schematic structural diagram of a conventional antenna feed system 100 provided in an embodiment of the present application. As shown in Figure 3, the primary component for signal transmission in the antenna feed system is an antenna 30, which includes a radiating element 3001 and a reflector 3002. The radiating element 3001, which can also be referred to as an antenna element or vibrator, is a unit that constitutes the basic structure of the antenna array and can effectively radiate or receive antenna signals. The frequencies of different radiating elements 3001 can be the same or different. The reflector 3002, which can also be referred to as a base plate, antenna panel, or metal reflective surface, can reflect and focus received signals at the receiving point. The radiating element 3001 is typically placed on one side of the reflector 3002, which not only greatly enhances signal reception or transmission capabilities but also blocks and shields interference signals from the back side of the reflector 3002. In this application, the back side of the reflector 3002 refers to the side of the reflector 3002 opposite to where the radiating element 3001 is located.

[0042] In the antenna feed system 100, to filter out interference noise from the antenna signal or select the signal frequency of the antenna signal, the radiating element 3001 of the antenna 30 is typically connected to the filter 40. As shown in FIG4 , FIG4 is a schematic diagram of a layout of the antenna 30 and the filter 40 of the antenna feed system 100 shown in FIG3 . Due to the limited spacing between the radiating elements 3001 in a conventional antenna feed system 100, the filter 40 can typically only be positioned outside the cavity of the antenna 30, that is, the filter 40 and the radiating element 3001 are respectively positioned on either side of the reflector 3002. This results in a larger size and weight for the entire antenna feed system 100, which in turn occupies more site space and antenna resources. In addition, since the antenna 30 and the filter 40 are independently arranged, the two must be connected through standard connectors and matching circuits, which will introduce additional losses. Moreover, since each radiating unit 3001 of the antenna 30 is connected to a filter 40 respectively, as the number of radiating units 3001 increases, the lengthening of the feed line thread caused by the external placement of the filter 40 will significantly reduce the overall efficiency of the antenna feed system 100.

[0043] In view of this, the filtering antenna provided by the present application realizes an integrated design of the radiating surface and the filter by sharing a metal back cavity with the radiating surface for radiating electromagnetic waves. This can help improve the integration of the antenna feed system and realize the miniaturization design of the antenna feed system. In addition, since the matching circuit between the filter and the radiating surface can be effectively simplified in the filtering antenna, the loss of the filtering antenna can be effectively reduced, which is conducive to improving the radiation efficiency of the filtering antenna and further improving the overall efficiency of the antenna feed system. In order to facilitate the understanding of the technical solution of the present application, the filtering antenna provided by the present application will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0044] Referring to Figure 5, Figure 5 is a schematic diagram of the structure of the filtering antenna provided in an embodiment of the present application. The filtering antenna includes a radiating surface 1. In the present application, the radiating surface 1 is a structure that excites antenna signals and is used to realize antenna signal radiation. In a specific configuration, the radiating surface 1 includes a dielectric substrate 101, a feeding network 102, and a radiating structure 103. The feeding network 102 and the radiating structure 103 can be arranged on the board surface of the dielectric substrate 101, wherein the feeding network 102 and the radiating structure 103 can be integrated into the dielectric substrate 101 through, but not limited to, connecting lines. The feeding network 102 includes a junction point 1021 and an adapter 1022, and the junction point 1021 and the adapter 1022 are connected by a conductive line 104. The radiating structure 103 includes a feeding patch 1031, and the adapter 1022 is also connected to the feeding patch 1031 by a conductive line 104, thereby realizing the connection between the feeding network 102 and the radiating structure 103.

[0045] It is worth mentioning that in the embodiment of the present application, the dielectric substrate 101 serves as a supporting structure for the feed network 102 and the radiating structure 103, which can be exemplarily a printed circuit board (PCB). In addition, the feed network 102 is a structure used to excite the radiating structure in the filter antenna. In the feed network 102, the junction 1021 can also be called a feed port, which is used to connect to the feed source to receive the electrical signal from the feed source. The adapter 1022 is used to modulate the phase of the electrical signal between the junction 1021 and the feed patch 1031. It can be understood that the radiating structure 103 is a structure used to radiate the antenna signal in the filter antenna. In the present application, the antenna signal is radiated in the form of electromagnetic waves. Therefore, in the following text of the present application, unless otherwise specified, the electromagnetic waves and antenna signals mentioned are the same concept.

[0046] 5 , the filtering antenna further includes a filter 40 and a metal back cavity 105. The dielectric substrate 101 is covered on the metal back cavity 105, and the filter 40 is accommodated in the metal back cavity 105. In addition, the filter 40 includes a probe 4001, and the probe 4001 is connected to the junction 1021. Since the filter 40 is connected to the feed source, the connection between the junction 1021 and the feed source can be achieved by connecting the probe 4001 of the filter 40 to the junction 1021, so that the feeding network 102 can excite electromagnetic waves, which can be radiated through the feeding patch 1031. At the same time, the filter 40 can filter the electrical signal between the junction 1021 and the feed source, so as to realize the function of the filter 40 to filter out interference noise in the electromagnetic wave or to select the signal frequency of the electromagnetic wave.

[0047] In the filtering antenna provided in the present application, the integrated design of the filter 40 and the radiating surface 1 is achieved by making the filter 40 and the radiating surface 1 share the metal back cavity 105, which can make the filtering antenna smaller in size, lighter in weight and lower in cost. In addition, since in the filtering antenna, the filter 40 and the radiating surface 1 are connected through the probe 4001 and the junction 1021, there is no additional current path, which can effectively reduce the loss of the filtering antenna, thereby helping to improve the radiation efficiency of the filtering antenna. It is worth mentioning that in a possible embodiment of the present application, the filter 40 and the radiating surface 1 can be connected only through the connection between the probe 4001 and the junction 1021, which helps to further reduce the loss of the filtering antenna.

[0048] In order to further understand the design principle of the filtering antenna provided in this application, the specific structure of the filtering antenna is described below.

[0049] In the filtering antenna shown in Figure 5, the feed patch 1031 is an orthogonally polarized feed patch 1031, that is, the polarization mode of the feed patch 1031 can be dual polarization. Exemplarily, the polarization mode of the feed patch 1031 is ±45°, or the polarization mode of the feed patch 1031 is 0° and 90°. The specific polarization mode of the feed patch 1031 is not limited in this application.

[0050] The specific shape of dielectric substrate 101 is not limited in this application; it can be exemplarily a rectangular plate. Furthermore, dielectric substrate 101 includes a first side 1011 and a second side 1012, where the length of first side 1011 is greater than or equal to the length of second side 1012. Therefore, first side 1011 can be understood as the long side of dielectric substrate 101, and second side 1012 can be understood as the short side of dielectric substrate 101. In this embodiment of the present application, for ease of description, the direction in which first side 1011 extends can be defined as the X direction, and the direction in which second side 1012 extends can be defined as the Y direction.

[0051] 5 , in the filtering antenna, the feeding network 102 includes two combining points 1021, which are spaced apart along the Y direction. In addition, each combining point 1021 is connected to a filter 40, so that each combining point 1021 is connected to a feed source, so that the two combining points 1021 can be fed separately or simultaneously. It can be understood that when one of the two combining points 1021 is excited, the polarization mode of the feeding patch 1031 is single polarization; and when the two combining points 1021 are excited at the same time, the polarization mode of the feeding patch 1031 is dual polarization.

[0052] It is worth mentioning that in the filtering antenna shown in Figure 5, the feeding network 102 is symmetrically arranged along the Y direction, so that when the two combining points 1021 of the feeding network 102 are excited at the same time, the polarization mode of the feeding patch 1031 is orthogonal polarization, thereby improving the cross-polarization of the electromagnetic waves radiated by the feeding patch 1031.

[0053] The specific connection method between the feed network 102 and the feed patch 1031 is not limited in this application. For example, the feed network 102 and the feed patch 1031 can be directly connected via the conductive wire 104. In other words, the conductive wire 104 disposed between the adapter 1022 and the feed patch 1031 is in contact with and connected to the adapter 1022, and is also in contact with and connected to the feed patch. Alternatively, the feed network 102 and the feed patch 1031 can be coupled and connected. Specifically, the conductive wire 104 disposed between the adapter 1022 and the feed patch 1031 can be in contact with and connected to the adapter 1022, but a gap exists between the conductive wire 104 and the feed patch 1031. In this case, the feed network 102 can couple and feed the feed patch 1031 through the gap.

[0054] In the present application, the conductive line 104 can be an air strip line, which helps reduce the power loss of the electrical signal transmitted between the feed network 102 and the feed network 102 and the feed patch 1031, thereby reducing the loss of electromagnetic waves radiated by the feed patch 1031, thereby improving the radiation efficiency of the filter antenna. In some possible embodiments of the present application, the conductive line 104 can also be configured as other possible forms, for example, the conductive line 104 is a metal trace formed on the dielectric substrate 101.

[0055] In addition, the adapter 1022 can also be configured as an air strip line, and the length of the adapter 1022 can be greater than 0 and less than or equal to one wavelength of the electromagnetic wave radiated by the radiating structure 103, so that the adapter 1022 can be used to modulate the phase of the electrical signal between the combining point 1021 and the feeding patch 1031. Of course, the adapter 1022 can also be configured in other possible forms. For example, the adapter 1022 can be a metal trace formed on the dielectric substrate 101.

[0056] In the filter antenna provided herein, to improve radiation efficiency, the radiating structure 103 further includes a metasurface 1032. In this application, metasurface 1032 is an artificial electromagnetic structure formed by subwavelength units arranged in a specific spatial arrangement. Metasurface 1032 can be used to adjust the electric field distribution of radiating surface 1, thereby improving the directivity coefficient of the electromagnetic waves radiated by feed patch 1031 and regulating the beam shape of the incident radiation pattern, such as the beam null position and depth.

[0057] As shown in FIG5 , the feed network 102, the feed patch 1031, and the metasurface 1032 can be arranged on the same surface of the dielectric substrate 101, and the surface of the dielectric substrate 101 used for arranging the feed network 102, the feed patch 1031, and the metasurface 1032 can face away from the metal back cavity 105. Alternatively, the surface of the dielectric substrate 101 used for arranging the feed network 102, the feed patch 1031, and the metasurface 1032 can face the metal back cavity 105, or in other words, the feed network 102, the feed patch 1031, and the metasurface 1032 can be located between the dielectric substrate 101 and the metal back cavity 105. In this way, an air cavity can be formed between the dielectric substrate 101 and the metal back cavity 105. Compared with a cavity filled with dielectric, this can effectively reduce the overall loss of the filter antenna, thereby facilitating an improvement in the radiation efficiency of the filter antenna.

[0058] It is worth mentioning that in the filtering antenna provided in the present application, by integrating the feed network 102, the feed patch 1031, and the metasurface 1032 into the dielectric substrate 101, the structure of the filtering antenna can be effectively simplified. When the feed network 102, the feed patch 1031, and the metasurface 1032 are arranged on the same surface of the dielectric substrate 101, the feed network 102, the feed patch 1031, and the metasurface 1032 can be formed at one time through the same processing process, which is conducive to reducing the processing complexity and production cost of the filtering antenna. In addition, when the side of the dielectric substrate 101 used to set the feed network 102, the feed patch 1031, and the metasurface 1032 faces the metal back cavity 105, by forming an air cavity between the dielectric substrate 101 and the metal back cavity 105, while reducing the transmission loss of the entire filtering antenna, it can also provide conditions for the feed network 102 and the metal back cavity 105 to form an air-suspended microstrip line structure, thereby reducing the transmission loss of the feed network 102. In addition, since the metasurface 1032 has electromagnetic bandgap characteristics for surface waves, it can suppress the propagation of surface waves within the operating frequency band of the filtering antenna, thereby suppressing the antenna mutual coupling caused by the propagation of surface waves, so as to realize the self-decoupling function of the filtering antenna and improve the isolation of the filtering antenna.

[0059] It is understood that in order to achieve coupled feeding between the feed patch 1031 and the metasurface 1032, the metasurface 1032 should be arranged adjacent to the feed patch 1031. In the present application, the number of metasurfaces 1032 is not limited, and it can be one or more. When there are multiple metasurfaces 1032, at least one of the multiple metasurfaces 1032 is arranged adjacent to the feed patch 1031. In addition, when there are multiple metasurfaces 1032, the multiple metasurfaces 1032 can all be arranged on the same surface of the dielectric substrate 101, or some of the metasurfaces 1032 can be arranged on the side of the dielectric substrate 101 facing the metal back cavity 105, while another part of the metasurface 1032 is arranged on the side of the dielectric substrate 101 facing away from the metal back cavity 105.

[0060] 5 , in the filtering antenna provided in the present application, the radiating structure 103 may include one or more feed patches 1031. When the radiating structure 103 includes multiple feed patches 1031, the multiple feed patches 1031 may be located between two adjacent metasurfaces 1032 to optimize the electric field distribution of the radiating surface 1. In other possible embodiments of the present application, the arrangement of the multiple feed patches 1031 and the multiple metasurfaces 1032 may be adjusted according to specific application scenarios to achieve the purpose of optimizing the electric field distribution of the radiating surface 1. For example, some feed patches 1031 may be located between two adjacent metasurfaces 1032, while other parts of the feed patches 1031 may be located on one side of a metasurface 1032, etc. They are not listed one by one here, but they should all be understood to fall within the scope of protection of the present application.

[0061] It is understood that since the X direction is the long side direction of the dielectric substrate 101, when the radiating structure 103 includes multiple feeding patches 1031, the multiple feeding patches 1031 can be arranged along the X direction. Furthermore, the multiple metasurfaces 1032 of the radiating structure 103 can also be arranged along the X direction. This can help optimize the electric field distribution of the radiating surface 1, thereby improving the radiation efficiency of the filter antenna.

[0062] FIG6 is a top view of the filtering antenna shown in FIG5 , showing three metasurfaces 1032. The metasurface 1032 includes a plurality of metasurface units 10321, which can be arranged according to a predetermined periodic pattern. For example, in FIG6 , the plurality of metasurface units 10321 of the metasurface 1032 are arranged in a matrix. In other possible embodiments, the plurality of metasurface units 10321 of the metasurface 1032 can also be arranged in a rotational arrangement or in other manners. The specific arrangement of the plurality of metasurface units 10321 of the metasurface 1032 is not limited in this application.

[0063] This application also does not limit the shape of the metasurface unit 10321 of the metasurface 1032. For example, the metasurface unit 10321 may be a regular shape such as a square, rectangle, triangle, rhombus or circle, or may be some possible irregular shapes. In addition, in each metasurface 1032, the arrangement periodicity of multiple metasurface units 10321 may be the same or different, and the shapes of multiple metasurface units 10321 may be the same or different. In addition, the arrangement methods of each metasurface 1032 arranged on the dielectric substrate 101 may be the same or different. That is to say, in the filtering antenna provided in this application, each metasurface 1032 can be reasonably designed according to the specific application scenario. They are not listed one by one here, but they should all be understood to fall within the scope of protection of this application.

[0064] It can be understood that in the filtering antenna provided in the present application, the radiation pattern of the electromagnetic waves radiated by the radiation structure 103 can be adjusted by adjusting the number of feeding patches 1031 and the number and size of the metasurfaces 1032 and the specific setting of the metasurface units 10321. For example, in the filtering antenna shown in Figure 6, the radiation structure 103 includes two feeding patches 1031 and three metasurfaces 1032. By adjusting the size of the three metasurfaces 1032 and the specific setting of the metasurface units 10321, the radiation pattern radiated by the radiation structure 103 can be equivalent to the radiation pattern of the three radiation units of a traditional antenna. That is to say, the radiation structure 103 of the filtering antenna provided in the present application can be equivalent to the three radiation units of a traditional antenna.

[0065] In actual application scenarios, the number of filter antenna feed patches 1031 can be designed and adjusted according to the array form or the required radiation effect. For example, referring to FIG7 , FIG7 is another structural schematic diagram of a filter antenna provided in an embodiment of the present application. The filter antenna includes four feed patches 1031 and six metasurfaces 1032. In the filter antenna, the specific setting of each metasurface 1032 can be adjusted so that the radiation structure 103 can be equivalent to the six radiation units of a traditional antenna. All possible settings of the filter antenna are not listed here, but they should all be understood to fall within the scope of protection of the present application.

[0066] It can be understood that the filtering antenna provided in the present application adopts the above-mentioned design method. When the radiation structure 103 includes multiple feed patches 1031, the feeding network 102 can still be connected to two feed sources, or even only to one feed source. It can greatly simplify the structure of the feeding network 102 while achieving the same or similar radiation effect as a traditional antenna connected to more feed sources, thereby helping to simplify the overall structure of the filtering antenna.

[0067] After understanding the configuration of the radiation surface 1 of the filtering antenna provided in the present application, the metal back cavity 105 and the filter 40 accommodated in the metal back cavity 105 are introduced next.

[0068] 5 , in the filtering antenna provided in the present application, the metal back cavity 105 includes a bottom plate 1051 and a side plate 1052 . The bottom plate 1051 is arranged opposite to the dielectric substrate 101 , and the side plate 1052 is located between the bottom plate 1051 and the dielectric substrate 101 . The side plate 1052 can be arranged around the bottom plate 1051 . In the present application, the dielectric substrate 101 covering the metal back cavity 105 can be understood as the dielectric substrate 101 being connected to the end of the side plate 1052 facing away from the bottom plate 1051 .

[0069] It is worth mentioning that in the present application, the bottom plate 1051 and the side plates 1052 of the metal back cavity 105 can both be closed surfaces, thereby forming a closed cavity between the dielectric substrate 101 and the metal back cavity 105. Furthermore, at least one of the bottom plate 1051 or the side plates 1052 of the metal back cavity 105 can be a hollow structure or include holes, or the side plates 1052 can be provided only at the top corners of the bottom plate 1051, so that the metal back cavity 105 has a semi-open or fully open frame structure, which helps reduce the weight of the filtering antenna.

[0070] In the present application, the filter 40 may be a cavity filter 40. The cavity filter 40 is usually cut from a whole piece of metal and has a firm structure. In addition, the cavity filter 40 has the advantages of wide frequency coverage, good consistency, flexible setting and high reliability.

[0071] As described above, the filter 40 is connected to the combining point 1021 via the probe 4001 to enable power feeding between the filter 40 and the feeding network 102. In the present application, the probe 4001 and the combining point 1021 can be coupled or connected via the conductive wire 104, as long as the transmission of electrical signals between the filter 40 and the feeding network 102 is achieved.

[0072] Referring to Figure 8, Figure 8 is a side view of the filter shown in Figure 5. In the filtering antenna provided in the present application, since the radiating surface 1 and the filter 40 share the metal back cavity 105, the overall size of the filtering antenna can be made smaller. In addition, by adopting the design scheme of the filtering antenna provided in the present application, on the basis of realizing the structural integration of the radiating surface 1 and the filter 40, it is also possible to make the radiating surface 1 replace the last or last multiple resonant cavities of the filter 40 through reasonable design to achieve deep fusion of the radiating surface 1 and the filter 40, which can effectively reduce the number of resonant cavities of the filter 40 itself. On the one hand, it can reduce the size of the filter 40, which is conducive to reducing the overall size of the filtering antenna, thereby facilitating the integration of the filtering antenna with other devices. On the other hand, it can reduce the loss caused by the resonant cavity.

[0073] In addition, when the radiating surface 1 replaces the last or last multiple resonant cavities of the filter 40, the adapter 1022 can be used to modulate the coupling phase between the last or last multiple resonant cavities of the filter 40 and the radiating surface 1, which can eliminate the connection joint between the filter 40 and the radiating surface 1 to simplify the matching network between the filter 40 and the radiating surface 1, thereby reducing link loss.

[0074] In practical applications, the size of the radiating surface 1 of the filtering antenna can be designed and adjusted according to the array configuration or the desired radiation effect. For example, referring to FIG. 5 , in the present application, the length of the first side 1011 of the dielectric substrate 101 can be made greater than or equal to one wavelength of the electromagnetic wave radiated by the radiating structure 103. This can make the beam width of the filtering antenna narrower in the X direction and ensure that the filtering antenna has good cross-polarization discrimination. In addition, by making the length of the first side 1011 of the dielectric substrate 101 greater than or equal to one wavelength of the electromagnetic wave radiated by the radiating structure 103, the size of the metal back cavity 105 along the X direction can meet the installation space requirements of the filter 40, and can also reduce the impact on the feeding network 102 and the feeding patch 1031.

[0075] In addition, the length of the second side 1012 of the dielectric substrate 101 is less than or equal to half the wavelength of the electromagnetic wave radiated by the radiating structure 103. This can make the beam width of the filtering antenna in the Y direction wider, ensure that the filtering antenna has good cross-polarization discrimination, and facilitate the formation of the filtering antenna array along the Y direction.

[0076] From the above introduction to the radiating surface 1, it can be known that in the filtering antenna provided by the present application, the direction pattern of the electromagnetic waves radiated by the radiating structure 103 can be adjusted by adjusting the number of feed patches 1031 and the number and size of the metasurface 1032 and the specific setting method of the metasurface unit 10321, so that the radiating structure 103 of the filtering antenna can be equivalent to multiple radiating units of a traditional antenna. In addition, because in the present application, the radiating structure 103 can be driven by a feed source, the filtering antenna provided by the present application can achieve the effect of one feed source driving multiple radiating units. Compared with the solution in which each radiating unit of the traditional antenna requires a feed source to drive, it can effectively reduce the number of feed sources, thereby reducing the number of filters 40, which is conducive to reducing the debugging cost of the filter 40 of the filtering antenna, and can also reduce the threads connecting the feed source and the radiating surface 1, thereby reducing losses.

[0077] In the above, the introduction of the radiating surface 1 of the filtering antenna is based on the feed patch 1031 of the radiating structure 103 being an orthogonal polarization feed patch 1031. When the feed patch 1031 is a single polarization patch, refer to FIG9 , which is another structural schematic diagram of the filtering antenna provided in the embodiment of the present application. In the filtering antenna shown in FIG9 , the feed network 102 includes a combining point 1021, and at this time, the other structures of the radiating surface 1 can be set with reference to the above-mentioned embodiments, and will not be described in detail here. In addition, it should be understood that various filtering antennas obtained by a series of deformations based on the design principle of the filtering antenna provided in the embodiment of the present application should be understood to fall within the scope of protection of the present application.

[0078] The filtering antenna provided in the present application can be used in an antenna feed system 100. Referring to FIG10 , FIG10 is a schematic structural diagram of the antenna feed system 100 provided in an embodiment of the present application. In addition to the filtering antenna, the antenna feed system 100 also includes a phase shifter 60. The phase shifter 60 is configured to adjust the electromagnetic waves radiated by the radiating structure 103 accordingly, thereby changing the electrical downtilt angle of the electromagnetic waves radiated by the radiating structure 103, thereby changing the radiation direction of the electromagnetic waves radiated by the radiating structure 103, to meet the signal coverage requirements of the filtering antenna.

[0079] 10 , the antenna system 100 further includes an amplifier 50 for amplifying the electromagnetic waves received or transmitted by the radiating structure 103. Furthermore, the antenna system 100 further includes a signal processing module 70 for processing the electromagnetic waves received or transmitted by the radiating structure 103.

[0080] In practical applications, the filtering antenna can be used individually or in an array according to the specific application scenario. When the filtering antenna is used in an array, the antenna feed system 100 includes multiple filtering antennas, which are arranged in an array, or multiple filtering antennas are arranged along the X direction or along the Y direction.

[0081] It is worth mentioning that, in the present application, in addition to the above structure, the antenna system 100 may also include other functional modules, which can be specifically configured according to the specific usage requirements of the antenna system 100 and are not listed one by one here.

[0082] 3 , in a conventional antenna feed system 100, the filter 40, amplifier 50, and phase shifter 60 are all disposed on the RF front-end circuit board 80. Furthermore, since each radiating element of the antenna is connected to a filter 40, the number of filters 40 in the antenna feed system 100 is relatively large, and the number of components disposed on the RF front-end circuit board 80 is relatively large, thereby making the overall volume of the antenna feed system 100 relatively large. Furthermore, with reference to FIG10 , the filtering antenna provided in the embodiment of the present application achieves an integrated design of the radiating surface 1 and the filter 40 by allowing the radiating surface 1 and the filter 40 to share a metal back cavity 105. This prevents the filter 40 from occupying the area of ​​the RF front-end circuit board 80 of the antenna feed system 100, thereby freeing up more space on the RF front-end circuit board 80, thereby increasing the degree of freedom in the configuration of the RF front-end circuit board 80 and reducing the cost, while also making it easier to achieve heat dissipation.

[0083] The above are only specific embodiments of the present application, but the scope of protection of this 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 filtering antenna, characterized in that: The invention comprises a radiating surface, a filter and a metal back cavity, wherein the radiating surface comprises a dielectric substrate, a feeding network and a radiating structure, wherein the feeding network and the radiating structure are arranged on the plate surface of the dielectric substrate, the dielectric substrate is covered on the metal back cavity, and the filter is accommodated in the metal back cavity, wherein: The feed network includes a combining point and an adapter, wherein the combining point and the adapter are connected via a conductive line; The radiating structure includes a feeding patch, and the adapter is connected to the feeding patch via a conductive line; The filter includes a probe connected to the combining point.

2. The filtering antenna according to claim 1, wherein The radiation structure further includes a metasurface, which is used to adjust the electric field distribution of the radiation surface.

3. The filtering antenna according to claim 2, wherein: The metasurface includes a plurality of metasurface units, and the plurality of metasurface units are arranged according to a set periodic pattern.

4. The filtering antenna according to claim 2 or 3, characterized in that: There are a plurality of metasurfaces, and at least one of the plurality of metasurfaces is arranged adjacent to the feed patch.

5. The filtering antenna according to claim 4, wherein: There are multiple feeding patches, and the multiple feeding patches are located between two adjacent metasurfaces.

6. The filtering antenna according to any one of claims 1 to 5, characterized in that: The dielectric substrate includes a first side and a second side connected to each other. The length of the first side is greater than or equal to the length of the second side. The length of the first side of the dielectric substrate is greater than or equal to a wavelength of the electromagnetic wave radiated by the radiation structure.

7. The filtering antenna according to claim 6, wherein: The length of the second side of the dielectric substrate is less than or equal to half the wavelength of the electromagnetic wave radiated by the radiating structure.

8. The filtering antenna according to any one of claims 1 to 7, characterized in that: The feed patch is an orthogonal polarization feed patch.

9. The filtering antenna according to claim 8, wherein: The filtering antenna includes two filters; the feeding network includes two combining points, and each combining point is respectively connected to the probe of one filter.

10. The filtering antenna according to any one of claims 1 to 7, characterized in that: The feeding patch is a single-polarization feeding patch, and the feeding network includes one combining point.

11. The filtering antenna according to any one of claims 1 to 10, characterized in that: The adapter is an air strip line, and the length of the adapter is greater than 0 and less than or equal to a wavelength of the electromagnetic wave radiated by the radiation structure.

12. The filtering antenna according to any one of claims 1 to 11, characterized in that: The filter is a cavity filter.

13. The filtering antenna according to any one of claims 1 to 12, characterized in that: The probe is coupled to the junction, or the probe is connected to the junction via a conductive line.

14. The filtering antenna according to any one of claims 1 to 13, characterized in that: The conductive wire is an air strip wire.

15. An antenna feed system, characterized in that: The invention comprises a phase shifter and the filtering antenna according to any one of claims 1 to 14.

16. The antenna feed system according to claim 15, wherein: The antenna feed system includes a plurality of the filtering antennas, and the plurality of the filtering antennas are arranged in an array.

17. A base station, characterized in that: It comprises a radio frequency processing unit, a baseband processing unit and the antenna feed system according to claim 15 or 16, wherein the baseband processing unit is connected to the antenna feed system through the radio frequency processing unit.

18. A communication system, characterized in that: The method comprises a terminal and the base station according to claim 17, wherein the terminal is communicatively connected with the base station.