Beam control unit and antenna system

Abstract

This application discloses a beam control unit and an antenna system, belonging to the field of wireless communication technology. The beam control unit includes an electromagnetic structure disposed in the air interface direction of the antenna array, and the electromagnetic structure is used to achieve beamforming of the antenna array. This application solves the problem of high antenna system loss caused by the complexity of the back-end feed network of the antenna array in the prior art.

Description

Technical Field

[0001] This application relates to the field of wireless communication technology, and more particularly to beam control units and antenna systems. Background Technology

[0002] A key feature of fifth-generation mobile communication systems is the use of beam-tunable antennas at both the link and infrastructure ends of the communication system. Beam-tunable antennas are an effective technology for improving system capacity and energy efficiency, as well as reducing interference in mobile communications. In current base station systems, antenna beam control is achieved through digital and mechanical control.

[0003] However, while digital control offers rapid response, the introduction of phase shifters increases system costs; and while mechanical control can improve antenna efficiency and reduce losses by altering the antenna's design through mechanical means, its structure may be more complex. Summary of the Invention

[0004] The main objective of this application is to provide a beam control unit and an antenna system, which aims to reduce the complexity of the back-end feed network of the antenna array, reduce the insertion loss of the antenna system, reduce the computational load of MIMO (Multiple-Input Multiple-Output), and improve the radiation performance of the antenna array.

[0005] To achieve the above objectives, embodiments of this application provide a beam control unit, the beam control unit comprising:

[0006] An electromagnetic structure is disposed in the air interface direction of the antenna array, and the electromagnetic structure is used to realize beamforming of the antenna array.

[0007] In some embodiments, the electromagnetic structure includes:

[0008] A metamaterial substrate that completely covers the aperture of the antenna array, the metamaterial substrate being used to adjust the phase of the antenna subarrays in the antenna array.

[0009] In some embodiments, the electromagnetic structure includes:

[0010] Multiple discrete dielectric substrates are disposed on the air interface of a designated antenna subarray in the antenna array. Each discrete dielectric substrate is used to adjust the phase of the designated antenna subarray. When each discrete dielectric substrate is loaded onto the air interface of the designated antenna subarray, the antenna array has a beam splitting function.

[0011] Furthermore, to achieve the above objectives, this application also provides an antenna system comprising: an antenna array, and a beam control unit disposed in the air interface direction of the antenna array as described above, wherein the antenna array loads the beam control unit through the air interface to achieve beamforming.

[0012] This application proposes a beam control unit and an antenna system. The beam control unit includes an electromagnetic structure disposed in the air interface direction of the antenna array. The electromagnetic structure is used to achieve beamforming of the antenna array. This application, by introducing a designed beam control unit above the antenna array, replaces traditional digital and mechanical beamforming techniques with air-loaded electronic modulation technology. This effectively reduces the complexity of the antenna array's back-end feed network, while also reducing system insertion loss, reducing MIMO computation, and improving the antenna array's radiation performance. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only a part of the embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 A schematic diagram of a traditional base station antenna used to achieve beam scanning;

[0015] Figure 2 A schematic diagram of a traditional base station antenna used for beamforming.

[0016] Figure 3 This is a schematic diagram of the structure of an antenna system provided in one embodiment of this application;

[0017] Figure 4 A schematic diagram of the structure of a metamaterial substrate related to a beam control unit provided in an embodiment of this application;

[0018] Figure 5 A waveform diagram illustrating beam scanning based on a metamaterial substrate in a beam control unit, provided as an embodiment of this application;

[0019] Figure 6 A waveform diagram illustrating pattern null compensation based on a metamaterial substrate in a beam control unit in an embodiment of this application;

[0020] Figure 7A waveform diagram illustrating beam suppression based on a metamaterial substrate in a beam control unit in an embodiment of this application;

[0021] Figure 8 A waveform diagram illustrating beamforming based on a metamaterial substrate in a beam control unit in an embodiment of this application;

[0022] Figure 9 This is a schematic diagram of the structure of an antenna system provided in another embodiment of this application;

[0023] Figure 10 A schematic diagram of a traditional base station antenna that uses a phase shifter to achieve beam splitting of the antenna array.

[0024] Figure 11 This is a waveform diagram illustrating beam splitting based on a discrete dielectric substrate in a beam control unit, as provided in another embodiment of this application. Detailed Implementation

[0025] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that the embodiments of this application can also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of the embodiments of this application with unnecessary detail.

[0026] It should be noted that although a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than that shown in the flowchart. The terms "first," "second," etc., in the specification, claims, and the aforementioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0027] It should also be understood that references to "one embodiment" or "some embodiments" in the specification of embodiments of this application mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0028] A key feature of fifth-generation mobile communication systems is the use of beam-tunable antennas at both the link and infrastructure ends. Beam tuning is an effective technology for improving system capacity and energy efficiency, as well as reducing interference in mobile communications. In current base station systems, antenna beam control is achieved through digital and mechanical modulation. For example, to achieve vertical beam scanning, phase shifters are typically introduced into the back-end circuitry of the antenna array to change the phase of the antenna elements. Furthermore, in LTE scenarios, to improve capacity and enable beam splitting, 180° phase shifters are introduced into the back-end of some antenna subarrays to achieve a 180° phase difference between different subarrays. To achieve horizontal beam tuning, beamforming is performed directly on the antenna through active ports. These beamforming methods all increase the power consumption of the active ports. In addition, to prevent signal interference, mechanical control methods are usually used to minimize interference from other signals to the antenna array.

[0029] However, while digital control offers rapid response, the introduction of phase shifters increases system costs; and while mechanical control can improve antenna efficiency and reduce losses by altering the antenna's design through mechanical means, its structure may be more complex.

[0030] Therefore, to replace traditional methods and reduce the power consumption of active ports, the above-mentioned beamforming function can be achieved through over-the-air loading. This application provides a beam control unit and an antenna system. The beam control unit includes an electromagnetic structure disposed in the over-the-air direction of the antenna array, and the electromagnetic structure is used to achieve beamforming of the antenna array. This application's embodiments introduce a designed beam control unit above the antenna array, replacing traditional digital and mechanical control techniques for beamforming with over-the-air (OTA) electronically tunable beams. For antenna arrays aiming for vertical beamforming, depending on the situation, an electromagnetic structure designed and loaded onto the antenna OTA is used to control the amplitude and phase of the electromagnetic waves radiated by the antenna. This not only increases the antenna's beam scanning capability and improves beam coverage, but also compensates for the gain null of the lower sidelobe, solving the problem of tower blacking in base station antenna systems. Furthermore, in cases of external signal interference, the OTA loading method can control the beam pattern to achieve nulling in the direction of the interfering electromagnetic wave, thus avoiding interference. For antenna arrays aiming for horizontal beamforming, the OTA loading method not only enables beam scanning and improves beam coverage, but also allows for the generation of specific beam pattern shapes as needed. This method can replace traditional mechanical electronic tuning or digital phase shifter methods, achieving rapid and accurate beamforming and improving the performance of base station antenna systems, such as reducing costs, reducing MIMO computation, and reducing losses.

[0031] The beam control unit and antenna system provided in the embodiments of the present application will be specifically described through the following embodiments. Refer to Figure 3 , Figure 3 FIG. is a schematic structural diagram of an antenna system provided in an embodiment of the present application. As Figure 3 shown, the antenna system provided in this embodiment includes:

[0032] An antenna array 1 and a beam control unit arranged in the air interface direction of the antenna array 1. The antenna array 1 realizes beamforming by loading the beam control unit through the air interface.

[0033] As an example, the antenna array includes:

[0034] Multiple antenna sub-arrays, and the array apertures of the antenna sub-arrays to be adjusted in phase or amplitude in each antenna sub-array are completely covered by the beam control unit.

[0035] As Figure 3 shown, the beam control unit provided in this embodiment includes:

[0036] An electromagnetic structure 5, which is arranged in the air interface direction of the antenna array 1 and is used to realize the beamforming of the antenna array 1.

[0037] In a traditional base station antenna system, the method for realizing the beam adjustment of the antenna array is as Figure 1 shown. It loads a phase shifter network 3 at the rear end of the antenna array 1 to change the phase distribution of the antenna elements, thereby realizing the adjustability of the beam direction of the antenna array. Figure 1 FIG. shows the system architecture for realizing array beam scanning in the traditional method. It includes N antenna sub-arrays 1. If beam directional radiation is to be realized, a metal reflector 2 needs to be introduced below. To realize the beam scanning function, N - 1 phase shifter units need to be introduced at the rear end of the antenna array 1. The bottommost is the power distribution network 4. The power distribution network leads out M ports, and M < N, where M and N are both natural numbers. The traditional method can change the phase of the antenna elements by loading a phase shifter network at the rear end of the antenna, thereby realizing the beam scanning function of the antenna array. In addition, beamforming can also be directly performed on the antenna array through the active ports at the rear end of the antenna elements, thereby realizing the adjustability of the antenna array pattern, as Figure 2 shown.

[0038] However, the aforementioned traditional solutions all achieve this through control on the circuitry at the antenna's back end, which makes the back-end network relatively complex. The beam control unit proposed in this embodiment, on the other hand, loads an electromagnetic structure 5 capable of amplitude or phase modulation onto the air interface of the antenna array 1, thereby achieving beam adjustment of the antenna array 1. This electromagnetic structure 5 can completely cover the antenna array. This embodiment replaces traditional electrically adjustable structures or phase-shifting structures on the circuitry, such as digital phase shifters, with air interface loading, improving the flexibility of base station antenna array shaping.

[0039] As an example, the antenna array 1 is a multi-channel antenna array, the electromagnetic structure 5 is an air-to-ground beam tunable electromagnetic structure, the antenna element form can be of various forms, and the electromagnetic structure can also be designed differently according to different requirements and antenna element forms.

[0040] As an example, the electromagnetic structure 5 is located above the multi-channel antenna array 1, and needs to completely cover the antenna array aperture, with the distance from the antenna array height not exceeding 0.25 times the wavelength at the operating frequency.

[0041] In some feasible embodiments, the electromagnetic structure 5 includes:

[0042] A metamaterial substrate that completely covers the aperture of the antenna array, the metamaterial substrate being used to adjust the phase of the antenna subarrays in the antenna array.

[0043] It should be noted that in this embodiment, the electromagnetic structure 5 can be a metasurface material with an adjustable metal structure layout. The metasurface material substrate is a metasurface material substrate. The metasurface structure designed in this embodiment has the ability to adjust the phase of the antenna subarray, and the adjustment range can cover the entire operating frequency band of the antenna. When the phase difference compensated by the metasurface structure is equal to the phase difference caused by the path difference in a certain direction, the radiation pattern of the antenna array can be deflected in that direction, realizing the function of beam scanning.

[0044] Reference Figure 4 In some feasible embodiments, the metamaterial substrate includes: a dielectric substrate 51, a metal structure 52, and an adjustable device 53. The metal structure 52 is printed on the upper surface and / or lower surface of the dielectric substrate 51, and a plurality of adjustable devices 53 are uniformly inserted between the metal structures 52 on the upper surface of the dielectric substrate 51. Each adjustable device 53 is used to control the transmission phase distribution of the antenna array 1.

[0045] As an example, the metal structure 52 may be printed only on the upper or lower surface of the dielectric substrate 51, or it may be printed on both the upper and lower surfaces of the dielectric substrate 51.

[0046] As an example, the adjustable device 53 can be a varactor diode, and the number of adjustable devices 53 can be four. Each varactor diode is controlled by a corresponding DC voltage. By changing the DC power supply bias value that controls each varactor diode, the corresponding capacitance value of the diode can be changed. That is, the distribution of the transmission phase of the array unit is controlled by adjusting the capacitance value of the varactor diode.

[0047] In some feasible embodiments, when the metamaterial substrate is loaded onto the air port of the antenna array, the antenna array has a beam scanning function.

[0048] As an example, refer to Figure 5 By loading the metamaterial substrate, which includes a metal structure 52 and an adjustable device 53, through an air interface, the antenna array can be equipped with beam scanning capabilities, thereby increasing the beam coverage.

[0049] Reference Figure 6 In some feasible embodiments, the metamaterial substrate is loaded onto the opening of the antenna array, and when the metal structure 52 and the adjustable device 53 are adjusted, the radiation pattern of the antenna array is compensated for the zero point of the lower sidelobe gain.

[0050] like Figure 6 As shown, in practical applications, base station antennas typically need to achieve beam downtilt functionality. However, in areas close to the base station antenna, the signal may be weak due to an excessively small lower sidelobe. Different metamaterial structures can be designed, and by loading adjustable devices onto these structures, the amplitude and phase of the electromagnetic waves radiated by the antenna subarray can be adjusted. This allows the beam of the antenna array with the metamaterial structure to cover the region at the original zero-gain point, thus compensating for the originally weak beam. Therefore, by loading the designed electromagnetic structure, the lower sidelobe can be compensated, thereby solving the problem of signal blackout at the user's tower.

[0051] Reference Figure 7 In some feasible embodiments, the metamaterial substrate is loaded onto the opening of the antenna array, and when the metal structure 52 and the adjustable device 53 are adjusted, the beam of the interference signal of the antenna array is suppressed in the direction of arrival.

[0052] It should be noted that in this embodiment, when the signal of antenna array 1 is subjected to other interference, the over-the-air loading method can suppress part of the beam to avoid interference. Since the electromagnetic structure of the over-the-air loading is a metamaterial structure loaded with tunable devices, by adjusting the tunable devices, the amplitude and phase of the electromagnetic waves radiated by the antenna array when passing through the metamaterial can be adjusted, so that the radiation field of the antenna array can be destructively superimposed in the opposite direction of the incoming wave of the interference signal, weakening the radiation field in the direction of the incoming wave of the interference signal, achieving null in that direction, thereby avoiding interference from other signals.

[0053] Reference Figure 8 In some feasible embodiments, when the metal structure 52 and the adjustable device 53 are adjusted and the metamaterial substrate is loaded onto the air port of the antenna array, the metamaterial substrate is used to adjust the amplitude and phase of the radiated electromagnetic waves so that the antenna array generates a specified waveform.

[0054] As an example, the electromagnetic structure 5 loaded over the air interface of antenna array 1 can also achieve other beamforming functions, such as... Figure 8 As shown, square waveforms can be generated as needed, thereby expanding the beam coverage area. The electromagnetic structure can also utilize a metamaterial structure loaded with adjustable devices. This metamaterial structure can be used to adjust the amplitude and phase of the radiated electromagnetic waves, thereby generating specific waveforms.

[0055] Combination Figure 3 and Figure 9 In this embodiment, the electromagnetic structure 5 includes:

[0056] Multiple discrete dielectric substrates 6 are disposed on the air interface of a designated antenna subarray in the antenna array. Each discrete dielectric substrate 6 is used to adjust the phase of the designated antenna subarray. When each discrete dielectric substrate 6 is loaded on the air interface of the designated antenna subarray, the antenna array has a beam splitting function.

[0057] As an example, in this embodiment, the antenna subarray is designated as antenna subarray 12.

[0058] In some embodiments, the discrete dielectric substrate 6 is a ceramic material dielectric substrate.

[0059] As an example, the discrete dielectric substrate 6 can also be other dielectric substrates with a dielectric constant greater than 9ε.

[0060] In some embodiments, the dielectric constant and thickness of each of the discrete dielectric substrates 6 are not exactly the same.

[0061] It should be noted that the electromagnetic structure 5 can be completely covering the antenna array as described in the above embodiments, or it can be loaded only on the antenna elements that require amplitude modulation or phase modulation, as in this embodiment. Using an open-hole loading method on different antenna elements can also enable the antenna array to generate multiple beams within the required angle, achieving beam splitting functionality.

[0062] As an example, the discrete dielectric substrate 6 is disposed above the antenna subarray 12 in the multi-channel antenna array 1, completely covering the array aperture of the antenna subarray 12, and the distance from the array height of the antenna subarray 12 does not exceed 0.25 times the wavelength at the operating frequency.

[0063] In existing designs, to achieve beam splitting, a 180° phase shifter is typically introduced at the rear end of part of the antenna, such as... Figure 10 As shown. Figure 10 A system architecture for beam splitting based on a phase shifter is demonstrated, comprising a first subarray 11 and a second subarray 12, with the first subarray 11 and the second subarray 12 placed adjacent to each other. The first subarray 11 contains N / 2 first sub-antennas, and the second subarray 12 contains N / 2 second sub-antennas. To achieve beam splitting, a 180° phase shifter is introduced at the rear-end circuitry of the second subarray 12. Similarly, at the bottom is a power divider network 4, which outputs M ports.

[0064] In this embodiment, to achieve the beam splitting function of the antenna array and replace the phase shifter in the original circuit, discrete electromagnetic structures, namely discrete dielectric substrates 6, can be loaded onto the antenna subarrays 12 that require phase modulation, such as... Figure 9 As shown, this electromagnetic structure can employ dielectric substrates with different high dielectric constants, such as ceramic materials. The relative dielectric constants and thicknesses of each dielectric substrate are (ε1,h1), (ε2,h2), ..., (ε...). N / 2,h N / 2). The phase of each antenna array can be varied by changing the dielectric constant and thickness of the ceramic material. Generally, the higher the dielectric constant and the thicker the ceramic material, the greater the phase change of the signal radiated by the antenna subarray. To achieve a 180° phase difference between the second subarray 12 and the first subarray 11, a discrete dielectric substrate with a suitable thickness and relative dielectric constant can be introduced above the second subarray. When the electromagnetic waves radiated by the second subarray pass through these discrete dielectric substrates, the incident wave will produce a 180° phase change, thereby achieving a beam splitting effect.

[0065] Reference Figure 11 In some embodiments, the number of antenna subarrays in the antenna array is adjustable.

[0066] It should be noted that when each of the discrete dielectric substrates is loaded onto the air port of the designated antenna subarray, the beam splitting effect of the antenna array will vary depending on the number of antenna subarrays in the antenna array. In this embodiment, the number of antenna subarrays 11 and the number of antenna subarrays 12 change simultaneously, and loading a corresponding number of discrete dielectric substrates onto the air port of antenna subarray 12 will result in different beam splitting effects.

[0067] As an example, by loading the discrete dielectric substrate 6 through the opening of the second subarray 12, the antenna array can have a beam-splitting function, and different beam-splitting effects can be achieved depending on the number of antenna subarrays. Figure 11This diagram illustrates dual-beam splitting. This method can also increase the beam coverage capability of an antenna array.

[0068] This embodiment provides a beam control unit and an antenna system. Based on over-the-air (OTA) loading electronic tuning technology, it can replace traditional OTA structures. By loading electromagnetic structures, the amplitude and phase of the electromagnetic waves radiated by the antenna are changed, thereby controlling the direction and shape of the beam. Compared to traditional OTA methods, OTA loading can effectively reduce the complexity of the network on the back-end circuitry of the antenna array, reduce system insertion loss, reduce MIMO computation, improve the reliability of antenna products, and enhance the radiation performance of the antenna array.

[0069] The beam control unit provided in this embodiment includes an electromagnetic structure that is not unique. It can be a metasurface material with an adjustable metal structure layout. By using different metal structure layouts, the metasurface structure can have different properties, thereby achieving changes in the amplitude or phase of the electromagnetic waves radiated by the antenna array. Alternatively, it can be a structure of multiple dielectric substrates with different dielectric constants. The discrete dielectric substrates can flexibly control the amplitude and phase of each antenna column.

[0070] The above is a detailed description of the preferred embodiments of this application. However, the embodiments of this application are not limited to the above-described implementation methods. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the embodiments of this application. All such equivalent modifications or substitutions are included within the scope defined by the claims of the embodiments of this application.

Claims

1. A beam control unit, characterized in that, The beam control unit includes: An electromagnetic structure is disposed in the air interface direction of the antenna array, and the electromagnetic structure is used to realize beamforming of the antenna array; The electromagnetic structure is located at a distance from the antenna array that does not exceed 0.25 times the wavelength at the operating frequency. The electromagnetic structure includes: multiple discrete dielectric substrates, each of which is disposed on the air interface of a designated antenna subarray in the antenna array. Each discrete dielectric substrate is used to adjust the phase of the designated antenna subarray. When each discrete dielectric substrate is loaded onto the air interface of the designated antenna subarray, the antenna array has a beam splitting function.

2. The beam control unit as described in claim 1, characterized in that, The electromagnetic structure includes: A metamaterial substrate that completely covers the aperture of the antenna array, the metamaterial substrate being used to adjust the phase of the antenna subarrays in the antenna array.

3. The beam control unit as described in claim 2, characterized in that, The metamaterial substrate includes: a dielectric substrate, metal structures, and adjustable devices. The metal structures are printed on the upper surface and / or lower surface of the dielectric substrate. A plurality of adjustable devices are uniformly inserted between the metal structures on the upper surface of the dielectric substrate. Each adjustable device is used to control the transmission phase distribution of the antenna array.

4. The beam control unit as described in claim 3, characterized in that, When the metamaterial substrate is loaded onto the air port of the antenna array, the antenna array has a beam scanning function.

5. The beam control unit as described in claim 3, characterized in that, When the metamaterial substrate is loaded onto the opening of the antenna array, and the metal structure and the adjustable device are adjusted, the radiation pattern of the antenna array is compensated for the zero point of the lower sidelobe gain.

6. The beam control unit as described in claim 3, characterized in that, When the metamaterial substrate is loaded onto the opening of the antenna array, and the metal structure and the adjustable device are adjusted, the beam of the interference signal of the antenna array is suppressed in the direction of arrival.

7. The beam control unit as described in claim 3, characterized in that, When the metamaterial substrate is loaded onto the air port of the antenna array and the metal structure and the adjustable device are adjusted, the metamaterial substrate is used to adjust the amplitude and phase of the radiated electromagnetic waves so that the antenna array generates a specified waveform.

8. The beam control unit as described in any one of claims 2 to 7, characterized in that, The metamaterial substrate is a metasurface material substrate.

9. The beam control unit as claimed in claim 1, characterized in that, The number of antenna subarrays in the antenna array is adjustable.

10. The beam control unit as claimed in claim 1, characterized in that, The discrete dielectric substrate is a ceramic material dielectric substrate.

11. The beam control unit as claimed in claim 1, characterized in that, The dielectric constant and thickness of each discrete dielectric substrate are not exactly the same.

12. An antenna system, characterized in that, The antenna system includes: an antenna array, and a beam control unit as described in any one of claims 1 to 11 disposed in the air interface direction of the antenna array, wherein the antenna array loads the beam control unit through the air interface to achieve beamforming.

13. The antenna system as claimed in claim 12, characterized in that, The antenna array includes: Multiple antenna subarrays, wherein the aperture of the antenna subarray whose phase or amplitude is to be adjusted is completely covered by the beam control unit.

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