Antenna array, phase center control method and base station

Abstract

Disclosed in the embodiments of the present application are an antenna array, a phase center control method, and a base station. The antenna array comprises a plurality of antenna subarrays. Each antenna subarray comprises a multi-modal antenna and a hybrid coupler; the hybrid coupler is used for inputting two signals from a first input end and a second input end, outputting a first feed signal to a first patch by means of a first output end, and outputting a second feed signal to a second patch by means of a second output end; the multi-modal antenna is used for exciting, on the basis of the first feed signal, the first patch to radiate a first electromagnetic wave, and exciting, on the basis of the second feed signal, the second patch to radiate a second electromagnetic wave; the phases of the two signals are used for controlling the power ratio and the phase difference between the second feed signal and the first feed signal, the power ratio and the phase difference being used for controlling the position of the phase center of the antenna subarray. The present application implements equivalent antenna array element position displacement, increases the adjustment speed, reduces control complexity, and improves ELAA spectral efficiency.

Description

Antenna array, phase center control method and base station

[0001] This application claims priority to Chinese Patent Application No. 202411519722.8, filed on October 29, 2024, entitled "Antenna Array, Phase Center Control Method and Base Station", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of communication technology, and in particular to an antenna array, a phase center control method, and a base station. Background Technology

[0003] With the advent of the 5.5G era in wireless communication, extremely large aperture arrays (ELAAs) have become a key technology for enhancing capacity, coverage, and user experience. Typically, the degrees of freedom available in ELAAs include array dimensions, drive relationships, and element amplitude and phase weights. Recently, movable antennas (MAs) have become increasingly popular, with research showing that the degrees of freedom offered by movable antennas, such as element position, orientation, and polarization, can further significantly improve system performance.

[0004] The implementation of movable antennas mainly focuses on mechanical motors, hydraulic fluids, and metals, but these methods suffer from problems such as slow movement speed and complex control methods. Summary of the Invention

[0005] This application provides an antenna array, a phase center control method, and a base station, which realizes the equivalent movement of antenna array element positions, improves the adjustable speed, reduces control complexity, and improves ELAA spectral efficiency.

[0006] In a first aspect, embodiments of this application provide an antenna array, the antenna array comprising a plurality of antenna subarrays, each of the antenna subarrays comprising a multimode antenna and a bridge, the bridge comprising a first input terminal and a second input terminal, a first output terminal and a second output terminal, and the multimode antenna comprising a first patch and a second patch;

[0007] The bridge is used to input two signals from the first input terminal and the second input terminal respectively, output a first feed signal to the first patch through the first output terminal, and output a second feed signal to the second patch through the second output terminal;

[0008] The multimode antenna is used to excite the first patch to radiate a first electromagnetic wave according to the first feed signal, and to excite the second patch to radiate a second electromagnetic wave according to the second feed signal.

[0009] The phase of the two signals is used to control the power ratio and phase difference between the second feed signal and the first feed signal, and the power ratio and phase difference are used to control the position of the phase center of the antenna subarray.

[0010] By using common components such as bridges and multimode antennas, the equivalent position of antenna array elements can be moved without the need for additional devices, thereby improving the adjustable speed, reducing control complexity, and improving ELAA spectral efficiency.

[0011] In one possible design, the first patch operates in TM11 mode and the second patch operates in TM21 mode.

[0012] In one possible design, when the excitation power of the second feed signal is 0, the phase center of the antenna subarray is located at the geometric center of the antenna subarray. The position of the phase center of the antenna subarray is adjusted by controlling the power ratio between the second feed signal and the first feed signal.

[0013] In one possible design, when the power ratio between the second feed signal and the first feed signal is 1:1, the phase center of the antenna subarray deviates from the wavelength of the electromagnetic wave by 0.25 times. The position of the phase center of the antenna subarray is adjusted by controlling the power ratio between the second feed signal and the first feed signal.

[0014] In one possible design, when the phase difference between the two signals is greater than or equal to 0 degrees and less than or equal to 90 degrees, the phase difference between the second feed signal and the first feed signal is in phase, and the phase center of the antenna subarray shifts in a first direction; when the phase difference between the two signals is greater than 90 degrees and less than or equal to 180 degrees, the phase difference between the second feed signal and the first feed signal is out of phase, and the phase center of the antenna subarray shifts in a second direction, wherein the first direction is opposite to the second direction. By controlling whether the second feed signal is in phase or out of phase with the first feed signal, the phase center of the antenna subarray is controlled to move in different directions.

[0015] In one possible design, the two signals have the same power.

[0016] In one possible design, each antenna subarray further includes two phase shifters connected to the first and second input terminals of the bridge, respectively, to adjust the phases of the two signals. By adjusting the phases of the two signals using the phase shifters, a different power ratio and phase difference are generated between the second feed signal and the first feed signal, thereby adjusting the position of the phase center of the antenna subarray.

[0017] In one possible design, each antenna subarray further includes two amplifiers connected to the first and second input terminals of the bridge, respectively, to amplify the power of the two signals. Amplifying the power of the two signals ensures the effective adjustment of the phase center of the antenna subarray.

[0018] In one possible design, the bridge is a 180-degree bridge.

[0019] In one possible design, the antenna array includes 24 digital channels: 6 horizontal and 4 vertical. Each digital channel includes multiple antenna subarrays, and each antenna subarray includes multiple multimode antennas.

[0020] In one possible design, the antenna array includes 48 digital channels, 6 horizontally and 8 vertically, each digital channel comprising an antenna subarray, and each antenna subarray comprising multiple multimode antennas.

[0021] In one possible design, each antenna subarray further includes a first combiner and a second combiner. The input of the first combiner is connected to the first output of the bridge, and the output of the first combiner is connected to a first patch in each of the plurality of multimode antennas. The input of the second combiner is connected to the second output of the bridge, and the output of the second combiner is connected to a second patch in each of the plurality of multimode antennas. The first combiner outputs the first feed signal to the first patch in the plurality of multimode antennas, and the second combiner outputs the second feed signal to the second patch in the plurality of multimode antennas. By using the combiner to split the feed signal into multiple signals and input them to the plurality of multimode antennas, the phase center of the plurality of multimode antennas can be adjusted simultaneously.

[0022] In one possible design, the antenna array includes 24 digital channels, 6 horizontal and 4 vertical, each digital channel corresponding to an antenna subarray, each digital channel including multiple antenna elements, and each antenna element including a multimode antenna.

[0023] Secondly, embodiments of this application provide a phase center control method. The antenna array includes multiple antenna subarrays, each antenna subarray including a multimode antenna and a bridge. The bridge includes a first input terminal and a second input terminal, a first output terminal and a second output terminal. The multimode antenna includes a first patch and a second patch. The first input terminal and the second input terminal are used to input two signals. The first output terminal is used to feed the first patch, and the second output terminal is used to feed the second patch. The method includes:

[0024] Determine the phase of each of the two signals;

[0025] Based on the phase of the two signals, control the power ratio and phase difference between the second feed signal input to the second patch and the first feed signal input to the first patch;

[0026] The position of the phase center of the antenna subarray is controlled based on the power ratio and the phase difference.

[0027] By using common components such as bridges and multimode antennas, the equivalent position of antenna array elements can be moved without the need for additional devices, thereby improving the adjustable speed, reducing control complexity, and improving ELAA spectral efficiency.

[0028] In one possible design, the first patch operates in TM11 mode and the second patch operates in TM21 mode.

[0029] In one possible design, when the excitation power of the second feed signal is 0, the phase center of the antenna subarray is located at the geometric center of the antenna subarray.

[0030] In one possible design, when the power ratio between the second feed signal and the first feed signal is 1:1, the phase center of the antenna subarray deviates from the wavelength of the electromagnetic wave by 0.25 times.

[0031] In one possible design, when the phase difference between the two signals is greater than or equal to 0 degrees and less than or equal to 90 degrees, the phase difference between the second feed signal and the first feed signal is in phase, and the phase center of the antenna subarray is shifted in a first direction; when the phase difference between the two signals is greater than 90 degrees and less than or equal to 180 degrees, the phase difference between the second feed signal and the first feed signal is out of phase, and the phase center of the antenna subarray is shifted in a second direction, wherein the first direction is opposite to the second direction.

[0032] In one possible design, the two signals have the same power.

[0033] In one possible design, the bridge is a 180-degree bridge.

[0034] Thirdly, embodiments of this application provide a base station including the antenna array described in the first aspect and any possible design of the first aspect.

[0035] It should be understood that the implementation and beneficial effects of the above-mentioned aspects or any possible implementation methods of this application can be referred to each other. Attached Figure Description

[0036] Figure 1A is a schematic diagram of the external shape of an active antenna module for a base station;

[0037] Figure 1B is a logic block diagram of the AAU module of the base station;

[0038] Figure 2 shows the phase center of the antenna subarray of a typical base station;

[0039] Figure 3 shows the phase center of the antenna subarray in an embodiment of this application;

[0040] Figure 4 is a comparison diagram of phase centers;

[0041] Figure 5 is a schematic diagram of an antenna subarray provided in an embodiment of this application;

[0042] Figure 6 is a schematic diagram of a multimode antenna provided in an embodiment of this application;

[0043] Figure 7 is a schematic diagram showing the correspondence between the power ratio and the phase center of two modes;

[0044] Figure 8 is a schematic diagram of a bridge provided in an embodiment of this application;

[0045] Figure 9 is a schematic diagram showing the relationship between the phase difference of two signals and the power ratio and phase difference;

[0046] Figures 10A-10D show the beam patterns when the phase center of a multimode antenna is adjusted.

[0047] Figure 11 is a schematic diagram of another antenna subarray provided in an embodiment of this application;

[0048] Figure 12 is a schematic diagram of another antenna subarray provided in an embodiment of this application;

[0049] Figure 13 is a schematic diagram of an antenna array;

[0050] Figure 14 is a schematic diagram of another type of antenna array;

[0051] Figure 15 is a schematic diagram of another type of antenna array;

[0052] Figure 16 is a schematic flowchart of a phase center control method provided in an embodiment of this application. Detailed Implementation

[0053] The following explains the main terms used in this application:

[0054] Phase center: refers to the equivalent point of the antenna's radiated or received signal. From the radiation perspective, the electromagnetic wave radiated by the antenna, after leaving the antenna at a certain distance, will have an equiphase surface that approximates a sphere, and the center of this sphere is the equivalent phase center of the antenna.

[0055] Existing methods for implementing movable antennas mainly include: First, using a stepper motor to drive a connecting rod, guiding the antenna vibrator to move within a certain range. Second, using a syringe to change the flow position of the electrolyte solution in the conduit, thereby moving the antenna radiator. Third, utilizing the characteristic that piezoelectric materials deform when subjected to input voltage, enabling them to generate mechanical vibrations at ultrasonic frequencies. Through a friction-driven mechanism, the ultrasonic motor, like an electromagnetic motor, can perform rotational or linear motion, thus driving the antenna vibrator to rotate or move.

[0056] However, the above solutions mainly suffer from two problems: slow adjustable speed and high control complexity. These technologies all rely on mechanical and physical movement, with adjustment speeds on the order of seconds, making it difficult to track and match the rapidly changing user channels in mobile communications. Stepper motors need to drive linkages to control antenna position. In a base station antenna array, if each antenna needs to move, the number of motors and linkages would be enormous, and interference could easily occur, hindering flexible movement. Microfluidics are also a complex system, requiring the use of syringes and catheters. Furthermore, the conductor in microfluidics is an electrolytic solution with generally low conductivity, resulting in significant antenna losses. Ultrasonic motors, originally used in camera focusing systems, would present significant challenges in antenna feeding if applied to base station antenna unit rotation, increasing control complexity.

[0057] Table 1

[0058] As shown in Table 1, the adjustable speeds of the three implementation methods (stepper motor, microfluidic, and ultrasonic motor) are all in the order of seconds, which results in slow adjustable speeds and high control complexity. To solve the above technical problems, the embodiments of this application provide the following solutions.

[0059] Figure 1A is a schematic diagram of the external shape of an active antenna unit (AAU) module of a base station. Figure 1B is a logic block diagram of the AAU module of the base station. The embodiments of this application mainly involve the radio frequency front-end and the antenna, as shown by the dashed box in Figure 1B. The base station can be a digital beamforming (DBF) base station or a hybrid beamforming (HBF) base station.

[0060] The phase center refers to the equivalent point from which an antenna radiates or receives signals. Changing the antenna's phase center is equivalent to effectively moving the antenna. Base station antenna arrays typically consist of multiple antenna subarrays. As shown in Figure 2, the phase center of an antenna subarray in a typical base station is fixed. As shown in Figure 3, the phase center of an antenna subarray in this embodiment can be varied within a certain range.

[0061] An antenna array is obtained by arranging multiple antenna subarrays according to the required number of rows and columns for a base station antenna. Figure 4 shows a comparison of phase centers. The black dots represent phase centers. The left side shows the antenna array of a typical base station, where the phase center of each antenna subarray cannot change and is generally located at the geometric center of the subarray. The right side shows the antenna array of a base station with adjustable phase centers, where the phase center of each antenna subarray can be moved to different positions. The structure of the antenna array in the embodiments of this application is described in detail below.

[0062] As shown in Figure 5, Figure 5 is a schematic diagram of an antenna subarray provided in an embodiment of this application. The antenna array includes multiple antenna subarrays, each of which includes a multimode antenna and a bridge. The bridge includes a first input terminal P1 and a second input terminal P2, a first output terminal P3 and a second output terminal P4. The multimode antenna includes a first patch and a second patch.

[0063] The bridge circuit is used to input two signals from the first input terminal P1 and the second input terminal P2, respectively, and outputs a first feed signal to the first patch through the first output terminal P3, and a second feed signal to the second patch through the second output terminal P4. The multimode antenna is used to excite the first patch to radiate a first electromagnetic wave according to the first feed signal, and to excite the second patch to radiate a second electromagnetic wave according to the second feed signal. The phase of the two signals is used to control the power ratio and phase difference between the second feed signal and the first feed signal, and the power ratio and phase difference are used to control the position of the phase center of the antenna subarray.

[0064] Optionally, the first patch operates in TM11 mode and the second patch operates in TM21 mode.

[0065] Optionally, when the excitation power of the second feed signal is 0, the phase center of the antenna subarray is located at the geometric center of the antenna subarray. When the power ratio between the second feed signal and the first feed signal is 1:1, the phase center of the antenna subarray deviates from the wavelength of the electromagnetic wave by 0.25 times.

[0066] Optionally, when the second feed signal and the first feed signal are in phase, the phase center of the antenna subarray shifts in a first direction; when the second feed signal and the first feed signal are out of phase, the phase center of the antenna subarray shifts in a second direction, wherein the first direction is opposite to the second direction.

[0067] Figure 6 is a schematic diagram of a multimode antenna provided in an embodiment of this application. The multimode antenna may include two radiators (i.e., patch 1 and patch 2). As shown in Figure 6, the colored part is patch 1 with radius a1, which can be excited to TM11 mode, and the colorless part is patch 2 with radius a2, which can be excited to TM21 mode. Patch 1 and patch 2 operate in TM11 mode and TM21 mode respectively, with different current distributions. Optionally, patch 1 and patch 2 can be placed on the same layer and excited from different feed points. The excitation power of TM11 mode is the power of the first feed signal, and the excitation power of TM21 mode is the power of the second feed signal. By controlling the power ratio A21 between the excitation power of TM21 mode and the excitation power of TM11 mode, the phase center can be adjusted.

[0068] Figure 7 illustrates the relationship between the power ratio and phase center of two modes. ATM21 represents the excitation power of mode TM21, ATM11 represents the excitation power of mode TM11, and A21 represents the power ratio between the excitation power of mode TM21 and mode TM11. When the power ratio is 0, i.e., the excitation power of mode TM21 is 0, the phase center offset of the multimode antenna is 0, meaning the phase center is located at the geometric center (coinciding). When the power ratio is 1:1, the phase center of the multimode antenna is offset by approximately 0.25λ (λ is the wavelength of the electromagnetic wave). Furthermore, the ± of the power ratio represents whether the two modes are in-phase or out-of-phase excitations, correspondingly shifting the phase center in the +x or -x direction. That is, if the two modes are in-phase, the phase center shifts in the +x direction; if the two modes are out-of-phase, the phase center shifts in the -x direction.

[0069] It should be noted that an antenna subarray may include multiple multimode antennas, each with its own phase center. The phase center of the antenna subarray may be the weighted average of the phase centers of the multiple multimode antennas.

[0070] Figure 8 is a schematic diagram of a bridge circuit provided in an embodiment of this application. This bridge circuit can be a 180-degree bridge. The input terminals of the bridge circuit include P1 and P2, and the output terminals include P3 and P4. When the phases of the two input signals P1 and P2 are adjusted, the power ratio and phase difference between the second feed signal output from P4 and the first feed signal output from P3 can be adjusted. Then, the first feed signal and the second feed signal are fed to patches 1 and 2 of the multimode antenna, respectively, to achieve phase center adjustment.

[0071] Furthermore, by inputting the two signals into the bridge circuit and adjusting the phase difference between them, the first and second feed signals can be adjusted to be in phase or out of phase. The power of the two signals can be the same. When the phase difference between the two signals is greater than or equal to 0 degrees and less than or equal to 90 degrees, the phase difference between the second and first feed signals is in phase, and the phase center of the antenna subarray shifts towards a first direction. When the phase difference between the two signals is greater than 90 degrees and less than or equal to 180 degrees, the phase difference between the second and first feed signals is out of phase, and the phase center of the antenna subarray shifts towards a second direction, wherein the first and second directions are opposite.

[0072] Figure 9 illustrates the relationship between the phase difference and power ratio of two signals. The waveforms in the figure represent the second and first feed signals, and the phase difference represents the phase difference between the two signals. As shown in Case 1, when the phase difference between the two signals is 0 degrees, the waveforms of the second and first feed signals coincide, meaning the power ratio of the second feed signal to the first feed signal is 1, and the second feed signal is in phase with the first feed signal. As shown in Case 4, when the phase difference between the two signals is 95 degrees, the power values ​​shown in the waveforms of the second and first feed signals are different, and the second feed signal is out of phase with the first feed signal. As shown in Case 6, when the phase difference between the two signals is 180 degrees, the power values ​​shown in the waveforms of the second and first feed signals are the same, meaning the power ratio of the second feed signal to the first feed signal is 1, and the second feed signal is out of phase with the first feed signal. Other cases are similar and will not be illustrated further here.

[0073] Figures 10A-10D show the beamforms of a multimode antenna when its phase center is adjusted. Figure 10A shows the beamform without phase center adjustment, with an equivalent spacing of 0.7 wavelengths between the phase centers of the two multimode antennas. Figure 10B shows the beamform with the phase centers adjusted to an equivalent spacing of 0.85 wavelengths. Figure 10C shows the beamform with the phase centers adjusted to an equivalent spacing of 1 wavelength. Figure 10D shows the beamform with the phase centers adjusted to an equivalent spacing of 0.4 wavelengths. The bold lines represent the waveforms of the actual physical spacing adjustment, while the dashed lines represent the waveforms of the phase center adjustment. It can be seen that the waveforms of the actual physical spacing adjustment largely coincide with those of the phase center adjustment, meaning that the multimode antenna achieves an equivalent adjustable physical spacing by adjusting the phase center.

[0074] Figure 11 is a schematic diagram of another antenna subarray provided in an embodiment of this application. This antenna subarray may include two phase shifters, two amplifiers, a bridge, multiple multimode antennas, and a combiner. The output of one phase shifter is connected to the input of one amplifier, and the output of the other phase shifter is connected to the input of another amplifier. The output of one amplifier is connected to the first input of the bridge, and the output of the other amplifier is connected to the second input of the bridge. Two signals are input to the phase shifters, adjusting the phase difference between the two signals. The amplifiers amplify the power of the two signals, and then the two signals after phase difference adjustment and power amplification are input to the bridge, which outputs a first feed signal and a second feed signal.

[0075] Each antenna subarray also includes a first combiner and a second combiner. The input of the first combiner is connected to the first output of the bridge, and the output of the first combiner is connected to the first patch of each of the multiple multimode antennas. The input of the second combiner is connected to the second output of the bridge, and the output of the second combiner is connected to the second patch of each of the multiple multimode antennas. The first combiner outputs a first feed signal to the first patch of the multiple multimode antennas, and the second combiner outputs a second feed signal to the second patch of the multiple multimode antennas. For example, the figure shows four multimode antennas. The combiner can split the first feed signal output by the bridge into four signals and input them to the first patches of the four multimode antennas respectively, and split the second feed signal output by the bridge into four signals and input them to the second patches of the four multimode antennas respectively.

[0076] Figure 12 is a schematic diagram of another antenna subarray provided in an embodiment of this application. This antenna subarray may include two phase shifters, two amplifiers, a bridge, and a multimode antenna. The output of one phase shifter is connected to the input of one amplifier, and the output of the other phase shifter is connected to the input of the other amplifier. The output of one amplifier is connected to the first input of the bridge, and the output of the other amplifier is connected to the second input of the bridge. Two signals are input to the phase shifters to adjust the phase difference between the two signals. The amplifiers amplify the power of the two signals, and then the two signals with adjusted phase difference and amplified power are input to the bridge. The bridge outputs a first feed signal and a second feed signal. The first feed signal is input to the first patch of the multimode antenna, and the second feed signal is input to the second patch of the multimode antenna.

[0077] Figure 13 shows a schematic diagram of an antenna array. This antenna array employs a hybrid beamforming (HBF) + subarray phase center adjustable (PCA) scheme. The array comprises 24 digital channels (H6V4) in total, with 6 horizontal and 4 vertical channels. Only one digital channel is shown in the figure. Each digital channel includes multiple antenna subarrays, and each subarray includes multiple multimode antennas.

[0078] Figure 14 shows a schematic diagram of another antenna array. This antenna array adopts a digital beamforming (DBF) + subarray PCA scheme. The antenna array includes 48 digital channels (H6V8) in total, with 6 horizontal and 8 vertical channels. Only two digital channels are shown in the figure. Each digital channel includes an antenna subarray, and each antenna subarray includes multiple multimode antennas.

[0079] The antenna subarrays in Figures 13 and 14 correspond to the antenna subarray shown in Figure 11. This subarray includes multiple multimode antennas. After the first and second feed signals are output through the first and second output terminals of the bridge, respectively, the first feed signal can be split into multiple signals by a first combiner and output to the first patches of the multiple multimode antennas, simultaneously exciting the first patches of the multiple multimode antennas to radiate a first electromagnetic wave. The second feed signal is split into multiple signals by a second combiner and output to the second patches of the multiple multimode antennas, simultaneously exciting the second patches of the multiple multimode antennas to radiate a second electromagnetic wave.

[0080] Figure 15 shows a schematic diagram of another antenna array. This antenna array uses a single-element PCA scheme. The array comprises 24 digital channels (6 horizontal and 4 vertical). Only one digital channel is shown in the figure. Each digital channel corresponds to one antenna subarray, and each digital channel includes multiple antenna elements. Four antenna elements are shown in the figure, and each antenna element includes a multimode antenna. The antenna subarray in Figure 15 corresponds to the antenna subarray shown in Figure 12.

[0081] Figure 16 is a flowchart illustrating a phase center control method provided in an embodiment of this application. The antenna array includes multiple antenna subarrays, each subarray including a multimode antenna and a bridge. The bridge includes a first input terminal, a second input terminal, a first output terminal, and a second output terminal. The multimode antenna includes a first patch and a second patch. The first and second input terminals are used to input two signals, the first output terminal is used to feed power to the first patch, and the second output terminal is used to feed power to the second patch. The method mainly includes the following steps:

[0082] S1601, determine the phase of the two signals respectively.

[0083] Specifically, the phase of the two signals can be adjusted using a phase shifter, so that the phase difference between the two signals is between 0 and 180 degrees. Then, the two phase-adjusted signals are input into a bridge circuit. The bridge circuit is a 180-degree bridge.

[0084] Optionally, the power of the two signals can be amplified by an amplifier, and then the amplified signals can be input into the bridge circuit respectively.

[0085] S1602, based on the phase of the two signals, control the power ratio and phase difference between the second feed signal input to the second patch and the first feed signal input to the first patch.

[0086] The phase difference between the two signals of the input bridge is 0 to 180 degrees, and the power of the two signals can be the same. The power ratio of the second feed signal to the first feed signal can be greater than or equal to 0, and the phase difference between the second feed signal and the first feed signal can be in phase or out of phase.

[0087] Specifically, by adjusting the phase of the two signals, the power ratio and phase difference between the second feed signal input to the second patch and the first feed signal input to the first patch are controlled. For example, when the phase difference between the two signals is 0 degrees, the power of the second feed signal and the first feed signal are the same, that is, the power ratio of the second feed signal to the first feed signal is 1, and the second feed signal is in phase with the first feed signal. When the phase difference between the two signals is 95 degrees, the power of the second feed signal and the first feed signal are different, and the second feed signal is out of phase with the first feed signal. When the phase difference between the two signals is 180 degrees, the power of the second feed signal and the first feed signal are the same, that is, the power ratio of the second feed signal to the first feed signal is 1, and the second feed signal is out of phase with the first feed signal.

[0088] The first patch operates in TM11 mode, and the second patch operates in TM21 mode.

[0089] S1603, control the position of the phase center of the antenna subarray according to the power ratio and the phase difference.

[0090] Specifically, when the excitation power of the second feed signal is 0, the phase center of the antenna subarray is located at the geometric center of the antenna subarray. When the power ratio between the second feed signal and the first feed signal is 1:1, the phase center of the antenna subarray deviates from 0.25 times the wavelength of the electromagnetic wave. Furthermore, when the phase difference between the two signals is greater than or equal to 0 degrees and less than or equal to 90 degrees, the phase difference between the second feed signal and the first feed signal is in phase, and the phase center of the antenna subarray shifts in a first direction; when the phase difference between the two signals is greater than 90 degrees and less than or equal to 180 degrees, the phase difference between the second feed signal and the first feed signal is out of phase, and the phase center of the antenna subarray shifts in a second direction, wherein the first direction is opposite to the second direction.

[0091] The solution adopted in this application embodiment can achieve the following technical effects:

[0092] First, improve system capacity. Analysis of antennas with adjustable phase center was conducted under the following conditions: a 64T base station, 50 users, and 4 antennas per user. Channel analysis revealed that antennas with adjustable phase center significantly improved the correlation between users; for example, the correlation between two user equipment (UE) devices decreased from 0.41 to 0.06.

[0093] Second, improve coverage. Analysis was conducted on three non-line of sight (NLOS) channel models, including clustered delay line (CDL) models: CDL-A, CDL-B, and CDL-C. In NLOS, due to varying multipath delays and angles, interference ripples are observed when the signal reaches the base station. In conventional antenna arrays, elements are located at fixed, regular receiving points, resulting in suboptimal received power. By using antennas with adjustable phase centers, the antennas are moved to their optimal receiving positions, thereby improving received power. Analysis shows that in the CDL-B case, the average coverage enhancement can reach 1.4 dB.

[0094] Third, interference nulls. The array factor of a traditional fixed antenna cannot be changed. However, by using the phase-center adjustable antenna of this application, the array factor can be changed, thereby altering the null position. When the equivalent phase center of the two subarrays changes, the null point changes from 33 degrees to 42 degrees.

[0095] Furthermore, the embodiments of this application utilize common components such as bridges and multimode antennas, eliminating the need for additional devices, to achieve equivalent movement of antenna array element positions, thereby improving adjustable speed, reducing control complexity, and enhancing ELAA spectral efficiency.

[0096] This application also provides a base station that includes the antenna array of any of the above.

[0097] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An antenna array, characterized in that, The antenna array includes multiple antenna subarrays, each antenna subarray includes a multimode antenna and a bridge, the bridge includes a first input terminal and a second input terminal, a first output terminal and a second output terminal, and the multimode antenna includes a first patch and a second patch; The bridge is used to input two signals from the first input terminal and the second input terminal respectively, output a first feed signal to the first patch through the first output terminal, and output a second feed signal to the second patch through the second output terminal; The multimode antenna is used to excite the first patch to radiate a first electromagnetic wave according to the first feed signal, and to excite the second patch to radiate a second electromagnetic wave according to the second feed signal. The phase of the two signals is used to control the power ratio and phase difference between the second feed signal and the first feed signal, and the power ratio and phase difference are used to control the position of the phase center of the antenna subarray.

2. The antenna array as described in claim 1, characterized in that, The first patch operates in TM11 mode, and the second patch operates in TM21 mode.

3. The antenna array as described in claim 1 or 2, characterized in that, When the excitation power of the second feed signal is 0, the phase center of the antenna subarray is located at the geometric center of the antenna subarray.

4. The antenna array as described in claim 1 or 2, characterized in that, When the power ratio between the second feed signal and the first feed signal is 1:1, the phase center of the antenna subarray deviates from the wavelength of the electromagnetic wave by 0.25 times.

5. The antenna array as described in any one of claims 1-4, characterized in that, When the phase difference between the two signals is greater than or equal to 0 degrees and less than or equal to 90 degrees, the phase difference between the second feed signal and the first feed signal is in phase, and the phase center of the antenna subarray shifts in the first direction; when the phase difference between the two signals is greater than 90 degrees and less than or equal to 180 degrees, the phase difference between the second feed signal and the first feed signal is out of phase, and the phase center of the antenna subarray shifts in the second direction, wherein the first direction is opposite to the second direction.

6. The antenna array as described in any one of claims 1-5, characterized in that, The two signals have the same power.

7. The antenna array as described in any one of claims 1-6, characterized in that, Each of the antenna subarrays further includes two phase shifters, which are respectively connected to the first input terminal and the second input terminal of the bridge, and are used to adjust the phase of the two signals respectively.

8. The antenna array as described in any one of claims 1-7, characterized in that, Each of the antenna subarrays further includes two amplifiers, which are respectively connected to the first input terminal and the second input terminal of the bridge, for amplifying the power of the two signals respectively.

9. The antenna array as described in any one of claims 1-8, characterized in that, The bridge is a 180-degree bridge.

10. The antenna array according to any one of claims 1-9, characterized in that, The antenna array includes 24 digital channels, 6 horizontal and 4 vertical. Each digital channel includes multiple antenna subarrays, and each antenna subarray includes multiple multimode antennas.

11. The antenna array as described in any one of claims 1-9, characterized in that, The antenna array includes 48 digital channels in total, with 6 horizontal and 8 vertical channels. Each digital channel includes an antenna subarray, and each antenna subarray includes multiple multimode antennas.

12. The antenna array as described in claim 10 or 11, characterized in that, Each of the antenna subarrays further includes a first combiner and a second combiner. The input of the first combiner is connected to the first output of the bridge, and the output of the first combiner is connected to a first patch in each of the plurality of multimode antennas. The input of the second combiner is connected to the second output of the bridge, and the output of the second combiner is connected to a second patch in each of the plurality of multimode antennas. The first combiner is used to output the first feed signal to the first patch in the plurality of multimode antennas, and the second combiner is used to output the second feed signal to the second patch in the plurality of multimode antennas.

13. The antenna array as described in any one of claims 1-9, characterized in that, The antenna array includes 24 digital channels, 6 horizontal and 4 vertical. Each digital channel corresponds to an antenna subarray, each digital channel includes multiple antenna elements, and each antenna element includes a multimode antenna.

14. A phase center control method, characterized in that, The method is applied to an antenna subarray, which includes multiple antenna subarrays. Each antenna subarray includes a multimode antenna and a bridge. The bridge includes a first input terminal and a second input terminal, a first output terminal and a second output terminal. The multimode antenna includes a first patch and a second patch. The first input terminal and the second input terminal are used to input two signals. The first output terminal is used to feed the first patch, and the second output terminal is used to feed the second patch. The method includes: Determine the phase of each of the two signals; Based on the phase of the two signals, control the power ratio and phase difference between the second feed signal input to the second patch and the first feed signal input to the first patch; The position of the phase center of the antenna subarray is controlled based on the power ratio and the phase difference.

15. The method as described in claim 14, characterized in that, The first patch operates in TM11 mode, and the second patch operates in TM21 mode.

16. The method as described in claim 14 or 15, characterized in that, When the excitation power of the second feed signal is 0, the phase center of the antenna subarray is located at the geometric center of the antenna subarray.

17. The method as described in claim 14 or 15, characterized in that, When the power ratio between the second feed signal and the first feed signal is 1:1, the phase center of the antenna subarray deviates from the wavelength of the electromagnetic wave by 0.25 times.

18. The method according to any one of claims 14-17, characterized in that, When the phase difference between the two signals is greater than or equal to 0 degrees and less than or equal to 90 degrees, the phase difference between the second feed signal and the first feed signal is in phase, and the phase center of the antenna subarray shifts in the first direction; when the phase difference between the two signals is greater than 90 degrees and less than or equal to 180 degrees, the phase difference between the second feed signal and the first feed signal is out of phase, and the phase center of the antenna subarray shifts in the second direction, wherein the first direction is opposite to the second direction.

19. The method according to any one of claims 14-18, characterized in that, The two signals have the same power.

20. The method according to any one of claims 14-19, characterized in that, The bridge is a 180-degree bridge.

21. A base station, characterized in that, Including the antenna array as described in any one of claims 1-13.

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