Antenna device and antenna system

Abstract

The invention discloses an antenna device and an antenna system. The antenna device is an antenna array formed by a plurality of microstrip antenna units. Each microstrip antenna unit comprises a dielectric substrate, a radiation patch, a metal bottom plate, a feed probe and a short circuit column. The radiation patch is located on the upper surface of the dielectric substrate, the metal bottom plate is located on the lower surface of the dielectric substrate, the feed probe penetrates through the dielectric substrate to connect one end of the radiation patch with the metal bottom plate, and the short circuit column penetrates through the dielectric substrate to connect the other end of the radiation patch with the metal bottom plate. By configuring the short circuit columns on the radiation patch and simultaneously exciting the first-order mode and the second-order mode, the radiation power of the microstrip antenna unit in the preset area can be suppressed to generate a radiation zero point, so that the signal radiated by the microstrip antenna unit can have asymmetry, and the asymmetry of the antenna array is further realized. The antenna system formed by adopting the antenna array can realize receiving and transmitting array coupling suppression of the antenna system, so that the isolation degree of a receiving and transmitting array surface is improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of communications, and in particular to an antenna device and an antenna system. Background Art

[0002] With the increasing demand for mobile communication capacity, not only the communication frequency of base stations is gradually developing towards high frequency bands that provide large bandwidth, but also higher requirements are placed on the full-duplex communication of high-frequency macro stations. For example, if a base station is responsible for the transmission of enhanced mobile broadband (eMBB) and uplink ultra-wideband (UL centric broadbandcommunication, UCBC) at the same time, it is required that eMBB and UCBC have a certain degree of isolation when working at the same frequency to minimize the mutual interference between the arrays in the station. Therefore, how to improve the isolation of the transceiver array to ensure the normal operation of the high-frequency macro station full-duplex system is the key research direction of current base station communications.

[0003] In this regard, traditional technology proposes to load an isolation wall in the transceiver antenna array, and to achieve decoupling between the transceiver array surfaces by loading a choke slot in the isolation wall, thereby improving the isolation of the transceiver array surfaces.

[0004] However, the decoupling structures (eg, isolation walls, choke slots, etc.) used in conventional technologies are relatively large in size and are difficult to apply to compact arrays, multiple-input multiple-output (MIMO) and other application scenarios.

[0005] Therefore, there is an urgent need for an antenna device that can solve the decoupling problem between the transmitting and receiving arrays and thus improve the isolation between the transmitting and receiving arrays. Summary of the invention

[0006] The present application provides an antenna device and an antenna system, which are used to suppress the coupling of the transmit and receive arrays of the antenna system by suppressing the radiation power at a specific angle, thereby improving the isolation of the transmit and receive arrays.

[0007] In a first aspect, the present application provides an antenna device, which is an antenna array composed of multiple microstrip antenna units. Each microstrip antenna unit includes at least one polarization unit, and each polarization unit includes a dielectric substrate, a radiating patch, a metal base plate, a feeding probe and a short-circuit post. The radiating patch is located on the upper surface of the dielectric substrate, the metal base plate is located on the lower surface of the dielectric substrate, the feeding probe passes through the dielectric substrate to connect one end of the radiating patch to the metal base plate, and the short-circuit post passes through the dielectric substrate to connect the other end of the radiating patch to the metal base plate. When the antenna device is working, each microstrip antenna unit is used to simultaneously excite the first-order mode and the second-order mode through the radiating patch to generate an asymmetric radiation signal at the working frequency. The asymmetric radiation signal has a radiation zero point in a preset area, and the working frequency is between the frequency corresponding to the first-order mode and the frequency corresponding to the second-order mode.

[0008] In the present application, by configuring a short-circuit post on the radiation patch and simultaneously exciting the first-order mode and the second-order mode, the radiation power of the microstrip antenna unit in a preset area can be suppressed to generate a radiation zero point, so that the signal radiated by the microstrip antenna unit can be asymmetric, and then the antenna signal radiated by the antenna array composed of the aforementioned multiple microstrip antenna units is also asymmetric. Therefore, the antenna system composed of the antenna array can achieve the coupling suppression of the antenna system's transceiver array, thereby improving the isolation of the transceiver array.

[0009] In a possible implementation, the short-circuit post is located near the electric wall generated by the second-order mode on the radiation patch, and the position of the short-circuit post does not overlap with the position of the electric wall generated by the first-order mode on the radiation patch.

[0010] In this embodiment, the short-circuit post is arranged near the electric wall of the second-order mode, which can move the resonant frequency of the first-order mode to a high frequency without affecting the resonant frequency of the second-order mode. Therefore, it is beneficial to bring the frequency corresponding to the first-order mode closer to the frequency corresponding to the second-order mode, thereby improving the matching effect of the antenna.

[0011] In a possible implementation manner, the distance between the short-circuit post and the feeding probe is greater than 3 / 4 times the length of the radiation patch, and the length of the radiation patch is related to the wavelength corresponding to the operating frequency.

[0012] In this embodiment, since the electric wall of the second-order mode is generally at 3 / 4 of the length of the radiation patch, after adjusting the amplitude and phase by adjusting the short-circuit post, the distance between the short-circuit post and the feeding probe is greater than 3 / 4 times the length of the radiation patch. This is beneficial for adjusting the radiation zero point to a preset area while ensuring that the microstrip antenna unit can radiate non-corresponding signals, thereby facilitating the coupling suppression of the antenna system's transceiver array and improving the isolation of the transceiver array.

[0013] In a possible implementation, the radiation patch presents a branch-loaded slow-wave transmission structure along the length direction, and the length of the radiation patch is less than or equal to 1 / 2 times the wavelength corresponding to the operating frequency.

[0014] Exemplarily, the length of the radiation patch is approximately equal to 0.4 times the wavelength corresponding to the operating frequency.

[0015] In this embodiment, when the operating frequency of the microstrip antenna unit is between the first-order mode and the second-order mode, the size of the microstrip antenna unit is relatively large and may not be suitable for compact array applications. Therefore, making the radiating patch into a branch-loaded slow-wave transmission structure is beneficial to shortening the size of the radiating patch and significantly reducing the waveguide wavelength, thereby achieving miniaturization of the microstrip antenna unit size.

[0016] In a possible implementation, at least one polarization unit is a ±45° dual-polarization unit, wherein the radiation patch of the +45° polarization unit and the radiation patch of the -45° polarization unit are placed crosswise, and an insulating medium is arranged between the radiation patch of the +45° polarization unit and the radiation patch of the -45° polarization unit.

[0017] In this embodiment, each microstrip antenna unit is configured as a dual-polarization unit. Compared with using a single-polarization unit to implement a microstrip antenna unit, the use of a dual-polarization unit not only increases the degree of freedom of the antenna, but also increases the communication capacity and improves the anti-interference capability, which is beneficial to improving the communication performance of the antenna device.

[0018] In a possible implementation manner, the distance between the short-circuit post of the +45° polarization unit and the end of the radiation patch of the +45° polarization unit is not equal to the distance between the short-circuit post of the −45° polarization unit and the end of the radiation patch of the −45° polarization unit.

[0019] In this embodiment, the distances between the short-circuit post and the ends of the radiation patches of the two polarization units are different, which is beneficial to increase the asymmetry of the radiation signal radiated by the microstrip antenna unit.

[0020] In a possible implementation, the microstrip antenna unit further includes a plurality of scattering columns, and the plurality of scattering columns are symmetrically distributed around the at least one polarization unit.

[0021] Exemplarily, multiple scattering columns are located on one side of the line connecting the positions of two feeding probes of the ±45° dual polarization unit, and the multiple scattering columns are symmetrically distributed based on the perpendicular bisector of the line connecting the positions of the two feeding probes, and the center distance between two adjacent scattering columns in the multiple scattering columns is consistent.

[0022] In this embodiment, after the scattering column is loaded, the surface current near the metal base plate where the microstrip antenna unit is located will be more concentrated in the area near the loaded scattering column. Therefore, by configuring the scattering column around at least one polarization unit of the microstrip antenna unit, it is beneficial to enhance the radiation power suppression effect of the preset area and enhance the asymmetry of the signal radiated by the microstrip antenna unit.

[0023] In a possible implementation manner, the antenna device further includes a plurality of electromagnetic bandgap structures, and the plurality of electromagnetic bandgap structures are evenly distributed around a subarray including at least two microstrip antenna units.

[0024] In this embodiment, the electromagnetic bandgap structure has frequency bandgap and phase bandgap characteristics, and can affect the propagation of electromagnetic waves within a certain frequency band. After multiple microstrip antenna units are arrayed, coupling may occur between the microstrip antenna units, resulting in a decrease in asymmetric performance (suppression performance). This embodiment suppresses the aforementioned coupling by adding an electromagnetic bandgap structure, thereby enhancing the isolation between the microstrip antenna units, which is conducive to strengthening the asymmetric performance (suppression performance), that is, it is conducive to keeping the asymmetric performance of the antenna array consistent with the asymmetric performance of the microstrip antenna unit.

[0025] In a possible implementation, the electromagnetic bandgap structure includes a metal column and a conductor sheet. The conductor sheet is located on a surface of a dielectric substrate, and the metal column penetrates the dielectric substrate and is connected to a geometric center of the conductor sheet.

[0026] In a possible implementation manner, the subarray includes two microstrip antenna units. For example, the subarray is a 1×2 subarray or a 2×1 subarray.

[0027] In a second aspect, the present application provides an antenna system, which includes a transmitting array and a receiving array. The transmitting array is used to transmit an asymmetric radiation signal; the receiving array is used to receive an asymmetric radiation signal. The transmitting array can be implemented by the antenna device described in any one of the embodiments of the first aspect, and the receiving array can be implemented by the antenna device described in any one of the embodiments of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic diagram of an embodiment of a microstrip antenna unit provided in the present application;

[0029] Figure 2A An example diagram of the design principle of the microstrip antenna unit provided in this application;

[0030] Figure 2B for Figure 2A An example diagram comparing the directional patterns of the microstrip antenna units corresponding to each step in the process;

[0031] Figure 3A A top view of the miniaturized microstrip antenna unit provided by the present application;

[0032] Figure 3B A three-dimensional diagram of the miniaturized microstrip antenna unit provided by the present application;

[0033] Figure 4A A three-dimensional diagram of the miniaturized dual-polarized microstrip antenna unit provided by the present application;

[0034] Figure 4B A top view and a cross-sectional view of the miniaturized dual-polarized microstrip antenna unit provided by the present application;

[0035] Figure 5A A three-dimensional diagram of a microstrip antenna unit provided by the present application and equipped with a scattering column;

[0036] Figure 5B A top view of a microstrip antenna unit provided in the present application and equipped with a scattering column;

[0037] Figure 6 Schematic diagram of surface current distribution on a metal base plate of the dual-polarized antenna unit of the present application when no scattering column is loaded and when scattering column is loaded;

[0038] Figure 7 An example diagram comparing the directional patterns of the dual-polarized antenna unit provided in the present application with those of a traditional dual-polarized antenna unit;

[0039] Fig. 8A A three-dimensional diagram of the electromagnetic bandgap structure provided for this application;

[0040] Figure 8B A top view of the electromagnetic bandgap structure provided in the present application;

[0041] Fig. 9 An example diagram of a dispersion curve obtained by simulating the electromagnetic bandgap structure provided in the present application under periodic boundary conditions;

[0042] Fig.10 An example diagram of an antenna array composed of multiple microstrip antenna units and multiple electromagnetic band gap structures provided by the present application;

[0043] Fig.11 An example diagram of the impedance bandwidth of the antenna array provided for this application;

[0044] Fig.12 An example diagram comparing the radiation patterns of the antenna array provided in this application and the traditional antenna array at 25.5 GHz;

[0045] Fig.13An example diagram comparing the port isolation of the antenna array provided in this application with that of a traditional antenna array;

[0046] Fig.14 An example diagram of an antenna system composed of an antenna array provided in this application. DETAILED DESCRIPTION

[0047] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0048] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way are interchangeable where appropriate, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0049] It should be understood that the term "and / or" in this article is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0050] The following is a brief introduction to the professional terms involved in this application:

[0051] Asymmetry: refers to the asymmetric radiation pattern of the antenna. Compared with the symmetrical radiation pattern of traditional antennas, the antenna unit proposed in this application can effectively suppress the radiation power in a specific lateral area, but does not suppress the radiation power in the same area on the opposite side, resulting in the radiation patterns on both sides not showing completely consistent characteristics, which is called asymmetry.

[0052] First-order mode: refers to the field intensity mode with only one half-wave in the electric field distribution along the length direction of the radiation patch of the microstrip antenna unit (i.e. the direction where the longer side is located). Figure 1As shown in FIG. 1 , if the direction of the longer side of the radiation patch is defined as the y direction, and the direction of the shorter side of the radiation patch is defined as the x direction, then the first-order mode is the TM01 mode. For another example, if the direction of the longer side of the radiation patch is defined as the x direction, and the direction of the shorter side of the radiation patch is defined as the y direction, then the first-order mode is the TM10 mode. Figure 1 The example shown is introduced.

[0053] Second-order mode: refers to the electric field distribution along the length direction of the radiation patch of the microstrip antenna unit (that is, the direction of the longer side) with two half-wave field strength patterns. For example, Figure 1 As shown in the figure, if the direction of the longer side of the radiation patch is defined as the y direction, and the direction of the shorter side of the radiation patch is defined as the x direction, then the second-order mode is the TM02 mode. For another example, if the direction of the longer side of the radiation patch is defined as the x direction, and the direction of the shorter side of the radiation patch is defined as the y direction, then the second-order mode is the TM20 mode. Figure 1 The example shown is introduced.

[0054] Electric wall: refers to a surface that satisfies the boundary conditions of an ideal conductor, that is, E and H are both 0 inside the conductor. The electric lines are perpendicular to the conductor surface; the magnetic lines are parallel to the conductor surface. Generally, the surface that intersects the electric lines perpendicularly is called an electric wall.

[0055] Space angle filtering antenna: compared with the symmetrical radiation pattern of the traditional antenna, the proposed antenna unit can effectively suppress the radiation power in a specific lateral angle area, thereby causing a radiation zero point in this direction. This antenna unit is a space angle filtering antenna.

[0056] The antenna device provided in the present application includes an antenna array composed of multiple microstrip antenna units. Since the directional pattern of the signal radiated by each microstrip antenna unit is asymmetric, the signal radiated by the antenna device as a whole also has good asymmetry, which is conducive to achieving the coupling suppression of the antenna system's transceiver array, thereby improving the isolation of the transceiver array.

[0057] Combine the following Figure 1 The structure of each microstrip antenna unit 10 is introduced as follows:

[0058] like Figure 1, which is a schematic diagram of an embodiment of a microstrip antenna unit 10 provided by the present application. Each microstrip antenna unit 10 includes a dielectric substrate 101, a radiation patch 102, a metal bottom plate 103, a feed probe 104 and a short-circuit post 105. It should be noted that when a plurality of microstrip antenna units 10 form an antenna array, the plurality of microstrip antenna units 10 share the same dielectric substrate 101, and the plurality of microstrip antenna units 10 share the same metal bottom plate 103.

[0059] The dielectric substrate 101 is composed of an insulating medium, and the radiation patch 102, the metal base plate 103, the feeding probe 104 and the short-circuit post 105 are respectively made of conductive materials such as metal. The dielectric substrate 101 is used to carry the radiation patch 102 and the metal base plate 103. The radiation patch 102 is located on the upper surface of the dielectric substrate 101 as a radiator, and the metal base plate 103 is located on the lower surface of the dielectric substrate 101 as a grounding plate. The feeding probe 104 is used as a feeding device to connect the radiation patch 102 and the metal base plate 103. The short-circuit post 105 is used as a short-circuit device to achieve short-circuit between the radiation patch 102 and the metal base plate 103. The feeding probe 104 and the short-circuit post 105 are respectively located at both ends of the radiation patch 102. For example, the feeding probe 104 penetrates the dielectric substrate 101 to connect one end of the radiation patch 102 to the metal bottom plate 103 , and the short-circuit post 105 penetrates the dielectric substrate 101 to connect the other end of the radiation patch 102 to the metal bottom plate 103 .

[0060] When the microstrip antenna unit 10 is working, the microstrip antenna unit 10 simultaneously excites the first-order mode and the second-order mode through the radiation patch 102 to generate an asymmetric radiation signal at the operating frequency. The asymmetric radiation signal has a radiation zero point in a preset area, and the operating frequency is between the frequency corresponding to the first-order mode and the frequency corresponding to the second-order mode.

[0061] Among them, the first-order mode is a field intensity mode with only one half-wave in the electric field distribution along the length direction (i.e., the direction where the longer side is located) of the radiation patch 102 of the microstrip antenna unit 10; the second-order mode is a field intensity mode with two half-waves in the electric field distribution along the length direction (i.e., the direction where the longer side is located) of the radiation patch 102 of the microstrip antenna unit 10. When the microstrip antenna unit 10 passes through the radiation patch 102 configured with the short-circuit post 105 and excites the first-order mode and the second-order mode at the same time, an unevenly distributed current is generated on the radiation patch 102 to radiate an asymmetric radiation signal. Among them, the asymmetric radiation signal has a radiation zero point in a preset area, that is, the radiation power of the antenna's directional pattern in the preset area is low, and the radiation power of the entire directional pattern presents an asymmetric distribution law. Optionally, the short-circuit post 105 is located near the electric wall generated by the second-order mode on the radiation patch, and the position of the short-circuit post 105 does not overlap with the electric wall generated by the first-order mode on the radiation patch.

[0062] For ease of understanding, the following Figure 2A The principle of the microstrip antenna unit radiating an asymmetric signal is introduced:

[0063] Figure 2A Step 1 in is an example diagram of a microstrip antenna unit that is not equipped with a short-circuit device and uses a feeding probe. When the microstrip antenna unit excites the first-order mode (for example, TM01 mode) and the second-order mode (for example, TM02 mode) at the same time, although the current distribution on the patch can be made uneven, the frequency point corresponding to the first-order mode and the frequency point corresponding to the second-order mode will be twice the difference, that is, the frequency point f2 corresponding to the second-order mode is equal to twice the frequency point corresponding to the first-order mode, and the two modes are difficult to match in the same frequency band. In order to successfully excite the two modes at the same time, the two modes are brought closer by loading short-circuit columns at the edge of the microstrip antenna unit, thereby improving the matching effect of the antenna. As shown Figure 2A As shown in step 2 of , a short-circuit post is arranged near the electric wall of the second-order mode to bring the frequency points corresponding to the two modes closer. For example, after the short-circuit post is arranged on the radiation patch, the center frequency of the first-order mode can be moved toward the second-order mode while the frequency of the second-order mode remains unchanged, thereby reducing the frequency difference between the first-order mode and the second-order mode. Figure 2A In step 2, the difference between f2 and f1 is less than Figure 2A The difference between f2 and f1 in . Then, Figure 2A As shown in step 3 of , moving the short-circuit post away from the feeding probe can adjust the current amplitude ratio and phase difference of the two modes while bringing the frequency points corresponding to the two modes closer, so that the signal radiated by the microstrip antenna unit suppresses the radiation energy in the preset area and a radiation zero point appears. Figure 2B In the example shown, by adjusting the position of the short-circuit post, the microstrip antenna unit has a radiation zero point near 60°. In this example, the short-circuit post is arranged near the electric wall of the second-order mode, which can move the resonant frequency of the first-order mode to a higher frequency without affecting the resonant frequency of the second-order mode. Therefore, it is helpful to bring the frequency corresponding to the first-order mode and the frequency corresponding to the second-order mode closer, thereby improving the matching effect of the antenna.

[0064] In this embodiment, by configuring the short-circuit post 105 on the radiation patch 102 and simultaneously exciting the first-order mode and the second-order mode, the radiation power of the microstrip antenna unit 10 in the preset area can be suppressed to generate a radiation zero point, so that the signal radiated by the microstrip antenna unit 10 can be asymmetric, and then the antenna signal radiated by the antenna array composed of the aforementioned multiple microstrip antenna units 10 is also asymmetric. Therefore, the antenna system composed of the antenna array can achieve the coupling suppression of the antenna system's transceiver array, thereby improving the isolation of the transceiver array.

[0065] Optionally, the distance between the short-circuit post 105 and the feeding probe 104 (ie Figure 1 L 0 ) is greater than the length of the radiation patch 102 (i.e. Figure 1 L 1 ), the length of the radiation patch 102 is related to the wavelength corresponding to the operating frequency. Exemplarily, the length of the radiation patch 102 is 0.5 times the wavelength corresponding to the operating frequency. Since the electric wall of the second-order mode is generally at 3 / 4 of the length of the radiation patch 102, after adjusting the amplitude and phase by adjusting the short-circuit post 105, the distance between the short-circuit post 105 and the feeding probe 104 is greater than 3 / 4 times the length of the radiation patch 102. It is beneficial to adjust the radiation zero point to a preset area while ensuring that the microstrip antenna unit can radiate non-corresponding signals, which is beneficial to achieve the coupling suppression of the transmit and receive arrays of the antenna system, thereby improving the isolation of the transmit and receive arrays.

[0066] Further, in a possible implementation manner, as Figure 3A and Figure 3B As shown, the radiation patch 102 presents a branch-loaded slow-wave transmission structure along the length direction. The branch-loaded slow-wave transmission structure presents a symmetrical sawtooth shape along the length direction of the radiation patch 102. Configuring the radiation patch 102 as a branch-loaded slow-wave transmission structure can reduce the size of the radiation patch 102 along the length direction, that is, when the same radiation signal is obtained, the length of the radiation patch configured as a branch-loaded slow-wave transmission structure (for example, Figure 3A L 1 ') is longer than the length of a normal rectangular radiating patch (e.g. Figure 1 L 1 ) is small. Optionally, the length of the radiation patch 102 is less than or equal to 1 / 2 times the wavelength corresponding to the operating frequency. Exemplarily, the length of the radiation patch 102 is approximately equal to 0.4 times the wavelength corresponding to the operating frequency. Exemplarily, the width of the radiation patch 102 is approximately equal to 0.08 times the wavelength corresponding to the operating frequency.

[0067] In the present embodiment, when the operating frequency of the microstrip antenna unit 10 is between the first-order mode and the second-order mode, the size of the microstrip antenna unit is relatively large (i.e., the size of the radiation patch along the length direction is relatively large, for example, the size of the radiation patch along the length direction is greater than or close to 1 / 2 times the wavelength corresponding to the operating frequency), and it may be difficult to be suitable for compact array applications. Therefore, making the radiation patch into a branch-loaded slow-wave transmission structure is beneficial to shortening the size of the radiation patch and significantly reducing the waveguide wavelength, thereby realizing the miniaturization of the microstrip antenna unit size.

[0068] Furthermore, each microstrip antenna unit 10 includes at least one polarization unit.

[0069] In a possible implementation, Figure 4A In the example (a) on the left, each microstrip antenna unit 10 includes a polarization unit, and each polarization unit includes a radiation patch 102, a feeding probe 104, and a short-circuit post 105. When multiple single-polarization microstrip antenna units 10 form an antenna array, the multiple microstrip antenna units 10 share the same dielectric substrate 101, and the multiple microstrip antenna units 10 share the same metal base plate 103.

[0070] In another possible implementation, Figure 4A In the example (b) on the left, each microstrip antenna unit 10 includes two polarization units with different polarization directions, that is, each microstrip antenna unit 10 is a dual-polarization unit. Since each polarization unit includes a radiation patch 102, a feeding probe 104 and a short-circuit post 105, each microstrip antenna unit 10 includes two radiation patches 102, two feeding probes 104 and two short-circuit posts 105, and the two polarization units share the same dielectric substrate 101 and the same metal bottom plate 103.

[0071] In such Figure 4A In the example (b) shown, the microstrip antenna unit 10 is a ±45° dual-polarization unit, wherein the radiation patch of the +45° polarization unit and the radiation patch of the -45° polarization unit are placed crosswise, and an insulating medium is provided between the radiation patch of the +45° polarization unit and the radiation patch of the -45° polarization unit.

[0072] For example, Figure 4B As shown, the microstrip antenna unit includes two layers of dielectric substrates (i.e., dielectric substrate 101-1 and dielectric substrate 101-2). Among them, the upper dielectric substrate 101-1 is mainly used to print the radiation patch 102-1 of the -45° polarization unit, and the lower dielectric substrate 101-2 is mainly used to print the radiation patch 102-2 of the +45° polarization unit and the metal base plate 103. For example, the radiation patch 102-1 of the -45° polarization unit is located on the upper surface of the upper dielectric substrate 101-1, the radiation patch 102-2 of the +45° polarization unit is located on the upper surface of the lower dielectric substrate 101-2, and the metal base plate 103 is located on the lower surface of the lower dielectric substrate 101-2.

[0073] Optionally, the distance between the short-circuit post 105 of the +45° polarization unit and the end of the radiation patch 102-2 of the +45° polarization unit is not equal to the distance between the short-circuit post 105 of the -45° polarization unit and the end of the radiation patch 102-1 of the -45° polarization unit.

[0074] In this embodiment, each microstrip antenna unit 10 is configured as a dual-polarization unit. Compared with using a single-polarization unit to implement the microstrip antenna unit 10, the use of a dual-polarization unit not only increases the degree of freedom of the antenna, but also increases the communication capacity and improves the anti-interference ability, thereby helping to improve the communication performance of the antenna system. In addition, the distances between the short-circuit post 105 and the ends of the radiation patches of the two polarization units are configured to be different, which is conducive to increasing the asymmetry of the radiation signal radiated by the microstrip antenna unit 10.

[0075] Furthermore, in a possible implementation manner, the microstrip antenna unit 10 further includes a plurality of scattering columns, and the plurality of scattering columns are symmetrically distributed around at least one polarization unit.

[0076] like Figure 5A and Figure 5B As shown, the microstrip antenna unit 10 includes a ±45° dual-polarization unit as an example for introduction. A plurality of scattering columns 106 are symmetrically distributed around the ±45° dual-polarization unit. Optionally, the plurality of scattering columns 106 are located on one side of a line connecting two feeding probes 104 of the ±45° dual-polarization unit, and the plurality of scattering columns 106 are symmetrically distributed based on a perpendicular midline connecting the two feeding probes 104.

[0077] Optionally, the center distances between two adjacent scattering columns 106 in the plurality of scattering columns 106 are consistent, that is, the plurality of scattering columns 106 are evenly distributed around the ±45° dual-polarization unit. Figure 5B In the example shown, 24 scattering columns 106 are arranged around the ±45° dual polarization unit. It should be understood that in practical applications, the number of scattering columns 106 arranged around the ±45° dual polarization unit can be adjusted, and accordingly, the center distance between two adjacent scattering columns 106 can also be adjusted, which is not limited here.

[0078] In one example, if Figure 5A and Figure 5B As shown, the radius R of the scattering column 106 1 The radius R of the short-circuit column 105 is 0.1 mm to 0.2 mm, and the center distance d4 of adjacent scattering columns 106 is 0.4 mm to 0.8 mm. 2 The length L of the radiation patch 102-1 of the -45° polarization unit is 0.05mm to 0.2mm. 3 3.3mm~3.9mm, width W 3 0.84 mm to 1.24 mm; the length L of the radiation patch 102-2 of the +45° polarization unit 4 3mm~3.6mm, width W 4 It is 0.84mm~1.24mm.

[0079] like Figure 6As shown in FIG. 1 , it is a schematic diagram of the surface current distribution on the metal bottom plate of the dual-polarized antenna unit of the present application when the scattering column is not loaded and when the scattering column is loaded. Figure 6 As shown, after the scattering column 106 is loaded, the surface current near the metal base plate 103 where the microstrip antenna unit 10 is located will be more concentrated in the area near the loaded scattering column 106. Therefore, by configuring the scattering column 106 around at least one polarization unit of the microstrip antenna unit 10, it is beneficial to enhance the radiation power suppression effect of the preset area and enhance the asymmetry of the signal radiated by the microstrip antenna unit 10.

[0080] In addition, if Figure 7 As shown, the directional diagram of the dual-polarized antenna unit with spatial angle filtering capability in the present application is compared with that of the traditional dual-polarized antenna unit at 25GHz. Compared with the traditional antenna unit, the sidelobe level of the dual-polarized antenna unit proposed in the present application is reduced by 3.8dB, that is, the sidelobe level at a specific angle can be effectively suppressed to achieve good asymmetry.

[0081] Furthermore, in a possible implementation, the antenna device provided by the present application further includes a plurality of electromagnetic band gap structures (EBG) 20. The electromagnetic band gap structure 20 is an artificial periodic structure having frequency band gap and phase band gap characteristics, and can affect the propagation of electromagnetic waves within a certain frequency band.

[0082] like Fig. 8A As shown, the electromagnetic bandgap structure 20 includes a metal column 201 and a conductor sheet 202. The conductor sheet 202 is located on the surface of the dielectric substrate 101. The metal column 201 penetrates the dielectric substrate 101 and is connected to the geometric center of the conductor sheet 202. For example, Fig. 8A As shown, the conductor sheet 202 in the electromagnetic bandgap structure 20 can be a square metal patch, and the metal column 201 coincides with the geometric center of the square patch. Since coupling may occur between the microstrip antenna units 10 after the multiple microstrip antenna units 10 are arrayed, resulting in a decrease in asymmetric performance (suppression performance), the electromagnetic bandgap structure 20 is added to suppress the aforementioned coupling, thereby enhancing the isolation between the microstrip antenna units 10, thereby strengthening the asymmetric performance (suppression performance), that is, it is conducive to keeping the asymmetric performance of the antenna array consistent with the asymmetric performance of the microstrip antenna unit.

[0083] In one example, if Figure 8B As shown, the radius R of the metal column 201 is 0.05 mm to 0.15 mm, and the length L of the square patch is 2 0.3mm~0.7mm, width W 2 The length L of the square patch is 0.3mm to 0.7mm. 2It is related to the working frequency of the antenna unit. Taking the working frequency of the antenna unit as 25.8G as an example, the length L of the square patch 2 Approximately equal to 0.04 times the wavelength of the operating frequency.

[0084] like Fig. 9 As shown in FIG. 1 , it is a dispersion curve obtained by simulating the electromagnetic bandgap structure 20 provided by the present application under periodic boundary conditions. Fig. 9 The simulation results shown show that at a certain size (for example, Figure 8B The dimensions shown in the figure) can effectively suppress surface waves at 19.5 GHz or even higher frequencies, thereby suppressing the radiation power in a preset area to obtain a radiation zero point.

[0085] Furthermore, a plurality of electromagnetic bandgap structures 20 are evenly distributed around a subarray including at least two microstrip antenna units 10. Optionally, a subarray includes 2 microstrip antenna units 10. For example, a subarray including at least two microstrip antenna units 10 is a 1×2 subarray or a 2×1 subarray. Optionally, a subarray includes 4 microstrip antenna units 10. For example, a subarray including at least two microstrip antenna units 10 is a 2×2 subarray. No limitation is made here. Compared to the solution in which a plurality of electromagnetic bandgap structures are distributed only in one microstrip antenna unit in the conventional technology, the present application evenly distributes a plurality of electric field bandgap structures around at least two microstrip antenna units, which is beneficial to maintain the consistency of the radiation direction of at least two microstrip antenna units, thereby ensuring the asymmetry of the directional pattern of the entire antenna device.

[0086] For example, a subarray including at least two microstrip antenna units 10 is taken as a 1×2 subarray. Fig.10 As shown, every two microstrip antenna units 10 form a subarray (i.e., a 1×2 subarray), and a plurality of electromagnetic bandgap structures 20 are evenly distributed around the 1×2 subarray. In addition, a plurality of subarray groups are regularly arranged into an antenna array, and a plurality of electromagnetic bandgap structures 20 are evenly distributed around each 1×2 subarray in the antenna array. Exemplarily, the row spacing between adjacent microstrip antenna units 10 in the antenna array is 0.6 times the wavelength corresponding to the operating frequency, and the column spacing between adjacent microstrip antenna units 10 is 0.5 times the wavelength corresponding to the operating frequency.

[0087] In one example, if Fig.10 As shown, the antenna array includes 64 dual-polarized antenna elements, the antenna array size is 8×8, and the row spacing d between adjacent microstrip antenna elements 10 is 1 The column spacing d between adjacent microstrip antenna units 10 is 7 mm to 8 mm. 2 5.75 mm to 6.75 mm; the adjacent spacing d between the electromagnetic band gap structures 20 3 It is 0.87mm~1.27mm.

[0088] like Fig.11 As shown in FIG. , it is the impedance bandwidth of the antenna array with spatial angle filtering capability proposed in this application. Fig.11 From the simulation results shown, it can be seen that the impedance bandwidth range of the antenna array is 24.7 to 27.1 GHz.

[0089] like Fig.12 As shown in FIG. 1 , the radiation pattern of the antenna array with spatial angle filtering capability proposed in this application is compared with that of the traditional antenna array at 25.5 GHz. Fig.12 It can be seen from the simulation results shown that, compared with the radiation pattern of a traditional antenna array at 25 GHz, the sidelobe level of the antenna array with spatial angle filtering capability proposed in the present application can be reduced by 3.89 dB.

[0090] like Fig.13 As shown in FIG. 1 , the port isolation comparison between the antenna array with spatial angle filtering capability proposed in this application and the traditional antenna array is shown. Fig.13 It can be seen from the simulation results that, compared with the traditional antenna array, within the entire frequency band of the antenna operation, the antenna array with spatial angle filtering capability proposed in the present application has a significant isolation improvement effect under ±15° spatial domain scanning, and the port isolation can be improved by 16.1dB.

[0091] like Fig.14 As shown in FIG. 1 , an example diagram of an antenna system composed of antenna arrays provided in the present application is shown. The antenna system includes a transmitting array and a receiving array. The specific implementation of the transmitting array and the receiving array is as described above. Fig.10 In the antenna device shown, the signal radiated by the transmitting array has a radiation null in a preset area, and the signal radiated by the receiving array has a radiation null in a preset area. The transmitting array and the receiving array are arranged oppositely on the sides having the radiation null, that is, the transmitting array and the receiving array are arranged oppositely on the sides having the sidelobe suppressed, so that the transmitting and receiving arrays can obtain good isolation, thereby improving the communication performance of the antenna.

[0092] In the present embodiment, not only is the radiation power suppressed in a preset area by the microstrip antenna unit 10 to generate a radiation zero point, but a 1×2 subarray is constructed by the electromagnetic bandgap structure 20 so that the directional diagrams of each microstrip antenna unit 10 in the array have good consistency. Therefore, the antenna array composed of the aforementioned microstrip antenna unit 10 and the electromagnetic bandgap structure 20 can not only achieve the coupling suppression of the transmit and receive arrays of the antenna system, thereby improving the isolation of the transmit and receive arrays, but also ensure that the transmit and receive antenna arrays still have good isolation under quasi-far field spacing and when independently scanning.

[0093] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An antenna device, characterized in that: include: An antenna array composed of multiple microstrip antenna units, each of which includes at least one polarization unit, each of which includes a dielectric substrate, a radiation patch, a metal bottom plate, a feeding probe and a short-circuit column, the radiation patch is located on the upper surface of the dielectric substrate, the metal bottom plate is located on the lower surface of the dielectric substrate, the feeding probe penetrates the dielectric substrate to connect one end of the radiation patch with the metal bottom plate, and the short-circuit column penetrates the dielectric substrate to connect the other end of the radiation patch with the metal bottom plate; Each of the microstrip antenna units is used to simultaneously excite the first-order mode and the second-order mode through the radiation patch to generate an asymmetric radiation signal at an operating frequency, wherein the asymmetric radiation signal has a radiation zero point in a preset area, and the operating frequency is between a frequency corresponding to the first-order mode and a frequency corresponding to the second-order mode.

2. The antenna device according to claim 1, characterized in that The short-circuit post is located near the electric wall generated by the second-order mode on the radiation patch, and the position of the short-circuit post does not overlap with the position of the electric wall generated by the first-order mode on the radiation patch.

3. The antenna device according to claim 1 or 2, characterized in that: The distance between the short-circuit post and the feeding probe is greater than 3 / 4 times the length of the radiation patch, and the length of the radiation patch is related to the wavelength corresponding to the operating frequency point.

4. The antenna device according to any one of claims 1 to 3, characterized in that: The radiation patch presents a branch-loaded slow-wave transmission structure along the length direction, and the length of the radiation patch is less than or equal to 1 / 2 times the wavelength corresponding to the working frequency.

5. The antenna device according to any one of claims 1 to 4, characterized in that: The at least one polarization unit is a ±45° dual polarization unit, wherein the radiation patch of the +45° polarization unit and the radiation patch of the -45° polarization unit are placed crosswise, and an insulating medium is arranged between the radiation patch of the +45° polarization unit and the radiation patch of the -45° polarization unit.

6. The antenna device according to claim 5, characterized in that The distance between the short-circuit post of the +45° polarization unit and the end of the radiation patch of the +45° polarization unit is not equal to the distance between the short-circuit post of the −45° polarization unit and the end of the radiation patch of the −45° polarization unit.

7. The antenna device according to any one of claims 1 to 6, characterized in that: The microstrip antenna unit further includes a plurality of scattering columns, and the plurality of scattering columns are symmetrically distributed around the at least one polarization unit.

8. The antenna device according to claim 7, characterized in that: The multiple scattering columns are located on one side of the line connecting the positions of the two feeding probes of the ±45° dual-polarization unit, the multiple scattering columns are symmetrically distributed based on the perpendicular bisector of the line connecting the positions of the two feeding probes, and the center distance between two adjacent scattering columns among the multiple scattering columns is consistent.

9. The antenna device according to any one of claims 1 to 8, characterized in that: The antenna device further comprises a plurality of electromagnetic bandgap structures, and the plurality of electromagnetic bandgap structures are evenly distributed around a subarray comprising at least two of the microstrip antenna units.

10. The antenna device according to claim 9, characterized in that: The electromagnetic bandgap structure comprises a metal column and a conductor sheet, wherein the conductor sheet is located on the surface of the dielectric substrate, and the metal column penetrates the dielectric substrate and is connected to the geometric center of the conductor sheet.

11. The antenna device according to claim 9 or 10, characterized in that: The subarray includes two microstrip antenna units, and the subarray is a 1×2 subarray or a 2×1 subarray.

12. An antenna system, characterized in that: include: A transmitting array and a receiving array, wherein the transmitting array is the antenna device according to any one of claims 1 to 11, and the receiving array is the antenna device according to any one of claims 1 to 11; The transmitting array is used to transmit an asymmetric radiation signal; The receiving array is used to receive the asymmetric radiation signal.

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