Antenna calibration method, device, equipment, storage medium and program product

Abstract

The present application provides a method, apparatus, device, storage medium and program product for antenna calibration. The method comprises: transmitting a downlink channel state information reference signal to a calibration terminal through an antenna array; determining a new calibration factor of the antenna array based on the channel state information fed back by the calibration terminal; and calibrating the antenna array based on the new calibration factor. The method of the present application transmits a downlink channel state information reference signal to a calibration terminal through an antenna array, and determines a new calibration factor of the antenna array based on the channel state information fed back by the calibration terminal. It can implement antenna calibration based on air interface feedback, does not require a hardware calibration network, and can effectively reduce calibration costs while better implementing antenna array calibration and improving downlink transmission performance.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a method, apparatus, device, storage medium, and program product for antenna calibration. Background Art

[0002] Multi-antenna technology is a key technology in 5G wireless communication systems. 5G wireless communication systems utilize downlink user measurements and feedback to obtain quantized UE (User Equipment) downlink channel information, thereby calculating the precoding matrix. Because the protocol-specified precoding matrix takes into account the specific structure of the antenna array, downlink precoding performance can be affected if the downlink antenna array is not calibrated. Summary of the Invention

[0003] The present application provides a method, apparatus, device, storage medium, and program product for antenna calibration.

[0004] In one aspect, the present application provides a method for antenna calibration, the method comprising:

[0005] Transmitting a downlink channel state information reference signal to the calibration terminal via an antenna array;

[0006] Determining a new calibration factor for the antenna array according to the channel state information fed back by the calibration terminal;

[0007] The antenna array is calibrated according to the new calibration factor.

[0008] Optionally, the channel state information includes a PMI, the PMI includes information about a phase difference between antennas in the same polarization direction, and determining a new calibration factor for the antenna array based on the channel state information fed back by the calibration terminal includes:

[0009] A first calibration factor of the antenna array is determined according to the PMI fed back by the calibration terminal.

[0010] Optionally, before transmitting the downlink channel state information reference signal to the calibration terminal through the antenna array, the method further includes:

[0011] When a first calibration trigger condition is met, determining an antenna group corresponding to the antenna array according to the number of antennas included in the antenna array, wherein each antenna group includes two polarized antenna pairs;

[0012] A calibration terminal corresponding to the antenna group is determined, and a 2-port channel state information reference signal for calibration is configured for the calibration terminal corresponding to the antenna group.

[0013] Optionally, after determining the first calibration factor of the antenna array according to the PMI fed back by the calibration terminal, the method further includes:

[0014] determining a plurality of different sets of candidate calibration factors for the antenna array based on the first calibration factor for the antenna array;

[0015] determining a plurality of consecutive feedback cycles based on a plurality of different sets of candidate calibration factors for the antenna array, the feedback cycles corresponding one-to-one to the candidate calibration factors;

[0016] In each feedback cycle, after calibrating the antenna array using the candidate calibration factor corresponding to the feedback cycle, transmitting a downlink channel state information reference signal to multiple calibration terminals through the calibrated antenna array;

[0017] A second calibration factor for the antenna array is determined according to the CQIs fed back by the multiple calibration terminals.

[0018] Optionally, the channel state information includes a CQI, and determining a new calibration factor of the antenna array according to the channel state information fed back by the calibration terminal includes:

[0019] A third calibration factor of the antenna array is determined according to the CQIs fed back by the multiple calibration terminals.

[0020] Optionally, transmitting a downlink channel state information reference signal to the calibration terminal through the antenna array includes:

[0021] When a second calibration trigger condition is met, determining a plurality of consecutive feedback cycles based on a plurality of different candidate calibration factors for the antenna array, the feedback cycles corresponding one-to-one to the candidate calibration factors;

[0022] In each feedback cycle, the antenna array is calibrated using the candidate calibration factor corresponding to the feedback cycle, and a downlink channel state information reference signal is transmitted to multiple calibration terminals through the calibrated antenna array.

[0023] Optionally, determining the second calibration factor or the third calibration factor of the antenna array according to the CQIs fed back by the multiple calibration terminals includes:

[0024] Determining a comprehensive CQI in each feedback cycle according to the CQIs fed back by the multiple calibration terminals in each feedback cycle;

[0025] The candidate calibration factor corresponding to the feedback period with the maximum comprehensive CQI is used as the second calibration factor or the third calibration factor of the antenna array.

[0026] Optionally, after determining the third calibration factor of the antenna array according to the CQIs fed back by the multiple calibration terminals, the method further includes:

[0027] Determining, according to the number of antennas included in the antenna array, an antenna group corresponding to the antenna array, wherein each antenna group includes two polarized antenna pairs;

[0028] Determining a calibration terminal corresponding to the antenna group, and configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group;

[0029] transmitting, through the antenna group, a downlink channel state information reference signal to a calibration terminal corresponding to the antenna group according to a third calibration factor of the antenna array;

[0030] A fourth calibration factor of the antenna array is determined according to the PMI fed back by the calibration terminal corresponding to the antenna group.

[0031] Optionally, determining the antenna group corresponding to the antenna array according to the number of antennas included in the antenna array includes:

[0032] If the antenna array includes four antennas and the four antennas form two polarized antenna pairs, the four antennas are regarded as an antenna group, and a calibration terminal corresponding to the antenna group is determined. The calibration terminal is a terminal used to calibrate the antenna group.

[0033] Optionally, determining the antenna group corresponding to the antenna array according to the number of antennas included in the antenna array includes:

[0034] If the number of antennas in the antenna array is greater than four, splitting the antenna array into multiple antenna groups, each antenna group including two polarized antenna pairs, using any polarized antenna pair as a reference antenna pair, and directly or indirectly associating any polarized antenna with the reference antenna pair through the multiple antenna groups;

[0035] If any polarized antenna pair and the reference antenna are in the same antenna group, determining that the any polarized antenna pair is directly associated with the reference antenna;

[0036] If any polarized antenna pair and the reference antenna pair are not in the same antenna group, and both the any polarized antenna and the reference antenna are directly associated with the first antenna pair, determining that the any polarized antenna is indirectly associated with the reference antenna;

[0037] If any one of the polarized antennas is indirectly associated with the second antenna pair, and the second antenna pair is indirectly associated with the reference antenna pair, it is determined that any one of the polarized antennas is indirectly associated with the reference antenna pair.

[0038] Optionally, splitting the antenna array into multiple antenna groups, each antenna group including two polarized antenna pairs, using any polarized antenna pair as a reference antenna pair, and directly or indirectly associating any polarized antenna with the reference antenna pair through the multiple antenna groups includes:

[0039] The antenna array is divided into multiple antenna groups, and any polarized antenna pair is used as a reference antenna pair. Each of the antenna groups includes the reference antenna pair.

[0040] Optionally, the determining a calibration terminal corresponding to the antenna group and configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group includes:

[0041] Determining a corresponding calibration terminal for each antenna group, and configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to each antenna group, wherein different antenna groups correspond to different calibration terminals;

[0042] or,

[0043] A calibration terminal shared by the multiple antenna groups is determined, and a 2-port channel state information reference signal for calibration is configured for the shared calibration terminal. Each of the antenna groups is calibrated in different time periods using the shared calibration terminal.

[0044] Optionally, determining the first calibration factor or the fourth calibration factor of the antenna array according to the PMI fed back by the calibration terminal corresponding to the antenna group includes:

[0045] Determining an expected calibration phase value corresponding to the antenna group according to a PMI pair fed back by a calibration terminal corresponding to the antenna group, wherein each PMI pair includes PMIs in two polarization directions;

[0046] Determining a calibration factor for the antenna group according to an expected calibration phase value corresponding to the antenna group;

[0047] A first calibration factor or a fourth calibration factor of the antenna array is determined according to the calibration factor of the antenna group.

[0048] Optionally, determining the calibration phase expected value corresponding to the antenna group according to the PMI pair fed back by the calibration terminal corresponding to the antenna group includes:

[0049] Determining a calibration phase difference coefficient for each PMI pair based on the PMI pairs fed back by each calibration terminal corresponding to the antenna group within a specific time period;

[0050] According to the calibration phase difference coefficient of each PMI pair, an expected calibration phase value corresponding to the antenna group is determined.

[0051] Optionally, determining the calibration phase expected value corresponding to the antenna group according to the calibration phase difference coefficient of each PMI pair includes:

[0052] Performing a time-based Kalman filter process on the calibration phase difference coefficient of each of the PMI pairs to determine the calibration phase expected value;

[0053] or,

[0054] According to the signal-to-noise ratio corresponding to each terminal, weighted averaging the calibration phase difference coefficients of the PMI pairs fed back by each terminal to determine the calibration phase expected value;

[0055] or,

[0056] The calibrated phase difference coefficient of any of the PMI pairs is one of the preset phase difference coefficients. According to the calibrated phase difference coefficient of each of the PMI pairs, the probability of each of the preset phase difference coefficients occurring within the specific time length is determined, and the preset phase difference coefficients are weighted and summed according to the probability of each of the preset phase difference coefficients occurring within the specific time length to obtain the expected value of the calibrated phase.

[0057] Optionally, determining the first calibration factor or the fourth calibration factor of the antenna array according to the PMI fed back by the calibration terminal corresponding to the antenna group includes:

[0058] Determine, within a specific time period, a calibration phase difference for each PMI pair based on the PMI pairs fed back by the calibration terminal corresponding to the antenna group at the current moment, wherein each PMI pair includes PMIs in two polarization directions;

[0059] Determining an expected phase difference value corresponding to the antenna group at a current moment according to the calibrated phase difference of each PMI pair;

[0060] Determining a calibration error coefficient corresponding to the antenna group at the current moment according to an expected phase difference value corresponding to the antenna group at the current moment;

[0061] If the calibration error coefficient corresponding to the antenna group at the current moment converges, determining the calibration factor of the antenna group according to the calibration error coefficient corresponding to the antenna group at the current moment;

[0062] A first calibration factor or a fourth calibration factor of the antenna array is determined according to the calibration factor of the antenna group.

[0063] Optionally, determining an expected phase difference value corresponding to the antenna group at a current moment according to the calibrated phase difference of each PMI pair includes:

[0064] Determining, based on the calibration phase difference of each of the PMI pairs, a probability of occurrence of the calibration phase difference of each of the PMI pairs at a current moment;

[0065] According to the probability of occurrence of the calibrated phase difference of each PMI at the current moment, the calibrated phase difference of each PMI pair is weighted and summed to obtain the expected phase difference value corresponding to the antenna group at the current moment.

[0066] Optionally, if the calibration error coefficient corresponding to the antenna group at the current moment converges, before determining the calibration factor of the antenna group according to the calibration error coefficient corresponding to the antenna group at the current moment, the method further includes:

[0067] If the difference between the calibration error coefficient corresponding to the antenna group at the current moment and the calibration error coefficient corresponding to the antenna group at the previous moment is within a preset range, it is determined that the calibration error coefficient corresponding to the antenna group at the current moment converges.

[0068] Optionally, determining the calibration error coefficient corresponding to the antenna group at the current moment according to the expected phase difference value corresponding to the antenna group at the current moment further includes:

[0069] Smoothing the expected phase difference value corresponding to the antenna group at the current moment and the expected phase difference value corresponding to the antenna group at the previous moment to obtain a smoothed expected phase difference value;

[0070] A calibration error coefficient corresponding to the antenna group at a current moment is determined according to the smoothed expected phase difference value.

[0071] Optionally, configuring a 2-port channel state information reference signal for calibration for a calibration terminal corresponding to the antenna group includes:

[0072] Two sets of 2-port channel state information reference signals are configured for the calibration terminal corresponding to the antenna group, wherein each set of channel state information reference signals is mapped to an antenna in one polarization direction, and two different sets of channel state information reference signals are mapped to antennas in different polarization directions.

[0073] Optionally, configuring a 2-port channel state information reference signal for calibration for a calibration terminal corresponding to the antenna group includes:

[0074] A set of 2-port channel state information reference signals is configured for the calibration terminal corresponding to the antenna group. The set of 2-port channel state information reference signals is mapped to antennas with different polarization directions in different time periods using a time division multiplexing method.

[0075] Optionally, determining a new calibration factor of the antenna array according to the channel state information fed back by the calibration terminal includes:

[0076] determining a new calibration factor of the antenna array on the broadband according to the channel state information fed back by the calibration terminal based on the broadband;

[0077] or,

[0078] A new calibration factor of the antenna array on each subband is determined according to the channel state information fed back by the calibration terminal based on each subband.

[0079] Optionally, after determining a new calibration factor of the antenna array on each subband according to the channel state information fed back by the calibration terminal based on each subband, the method further includes:

[0080] A smoothing process is performed on the new calibration factor of the antenna array in each sub-band.

[0081] Optionally, calibrating the antenna array according to the new calibration factor includes:

[0082] Smoothing the calibration factor currently used by the array antenna and the new calibration factor to obtain a revised calibration factor;

[0083] The antennas in the antenna array are calibrated using the corrected calibration factors.

[0084] On the other hand, the present application provides an antenna calibration device, including a memory, a transceiver, and a processor:

[0085] Memory for storing computer programs;

[0086] a transceiver, configured to transmit and receive data under the control of the processor;

[0087] A processor is configured to read the computer program in the memory and perform the following operations:

[0088] A downlink channel state information reference signal is transmitted to a calibration terminal through an antenna array; a new calibration factor of the antenna array is determined based on the channel state information fed back by the calibration terminal; and the antenna array is calibrated based on the new calibration factor.

[0089] Optionally, the channel state information includes a PMI, the PMI includes information about a phase difference between antennas in the same polarization direction, and determining a new calibration factor for the antenna array based on the channel state information fed back by the calibration terminal includes:

[0090] A first calibration factor of the antenna array is determined according to the PMI fed back by the calibration terminal.

[0091] Optionally, before transmitting the downlink channel state information reference signal to the calibration terminal through the antenna array, the method further includes:

[0092] When a first calibration trigger condition is met, determining an antenna group corresponding to the antenna array according to the number of antennas included in the antenna array, wherein each antenna group includes two polarized antenna pairs;

[0093] A calibration terminal corresponding to the antenna group is determined, and a 2-port channel state information reference signal for calibration is configured for the calibration terminal corresponding to the antenna group.

[0094] Optionally, after determining the first calibration factor of the antenna array according to the PMI fed back by the calibration terminal, the method further includes:

[0095] determining a plurality of different sets of candidate calibration factors for the antenna array based on the first calibration factor for the antenna array;

[0096] determining a plurality of consecutive feedback cycles based on a plurality of different sets of candidate calibration factors for the antenna array, the feedback cycles corresponding one-to-one to the candidate calibration factors;

[0097] In each feedback cycle, after calibrating the antenna array using the candidate calibration factor corresponding to the feedback cycle, transmitting a downlink channel state information reference signal to multiple calibration terminals through the calibrated antenna array;

[0098] A second calibration factor for the antenna array is determined according to the CQIs fed back by the multiple calibration terminals.

[0099] Optionally, the channel state information includes a CQI, and determining a new calibration factor of the antenna array according to the channel state information fed back by the calibration terminal includes:

[0100] A third calibration factor of the antenna array is determined according to the CQIs fed back by the multiple calibration terminals.

[0101] Optionally, transmitting a downlink channel state information reference signal to the calibration terminal through the antenna array includes:

[0102] When a second calibration trigger condition is met, determining a plurality of consecutive feedback cycles based on a plurality of different candidate calibration factors for the antenna array, the feedback cycles corresponding one-to-one to the candidate calibration factors;

[0103] In each feedback cycle, the antenna array is calibrated using the candidate calibration factor corresponding to the feedback cycle, and a downlink channel state information reference signal is transmitted to multiple calibration terminals through the calibrated antenna array.

[0104] Optionally, determining the second calibration factor or the third calibration factor of the antenna array according to the CQIs fed back by the multiple calibration terminals includes:

[0105] Determining a comprehensive CQI in each feedback cycle according to the CQIs fed back by the multiple calibration terminals in each feedback cycle;

[0106] The candidate calibration factor corresponding to the feedback period with the maximum comprehensive CQI is used as the second calibration factor or the third calibration factor of the antenna array.

[0107] Optionally, after determining the third calibration factor of the antenna array according to the CQIs fed back by the multiple calibration terminals, the method further includes:

[0108] Determining, according to the number of antennas included in the antenna array, an antenna group corresponding to the antenna array, wherein each antenna group includes two polarized antenna pairs;

[0109] Determining a calibration terminal corresponding to the antenna group, and configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group;

[0110] transmitting, through the antenna group, a downlink channel state information reference signal to a calibration terminal corresponding to the antenna group according to a third calibration factor of the antenna array;

[0111] A fourth calibration factor of the antenna array is determined according to the PMI fed back by the calibration terminal corresponding to the antenna group.

[0112] Optionally, determining the antenna group corresponding to the antenna array according to the number of antennas included in the antenna array includes:

[0113] If the antenna array includes four antennas and the four antennas form two polarized antenna pairs, the four antennas are regarded as an antenna group, and a calibration terminal corresponding to the antenna group is determined. The calibration terminal is a terminal used to calibrate the antenna group.

[0114] Optionally, determining the antenna group corresponding to the antenna array according to the number of antennas included in the antenna array includes:

[0115] If the number of antennas in the antenna array is greater than four, splitting the antenna array into multiple antenna groups, each antenna group including two polarized antenna pairs, using any polarized antenna pair as a reference antenna pair, and directly or indirectly associating any polarized antenna with the reference antenna pair through the multiple antenna groups;

[0116] If any polarized antenna pair and the reference antenna are in the same antenna group, determining that the any polarized antenna pair is directly associated with the reference antenna;

[0117] If any polarized antenna pair and the reference antenna pair are not in the same antenna group, and both the any polarized antenna and the reference antenna are directly associated with the first antenna pair, determining that the any polarized antenna is indirectly associated with the reference antenna;

[0118] If any one of the polarized antennas is indirectly associated with the second antenna pair, and the second antenna pair is indirectly associated with the reference antenna pair, it is determined that any one of the polarized antennas is indirectly associated with the reference antenna pair.

[0119] Optionally, splitting the antenna array into multiple antenna groups, each antenna group including two polarized antenna pairs, using any polarized antenna pair as a reference antenna pair, and directly or indirectly associating any polarized antenna with the reference antenna pair through the multiple antenna groups includes:

[0120] The antenna array is divided into multiple antenna groups, and any polarized antenna pair is used as a reference antenna pair. Each of the antenna groups includes the reference antenna pair.

[0121] Optionally, the determining a calibration terminal corresponding to the antenna group and configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group includes:

[0122] Determining a corresponding calibration terminal for each antenna group, and configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to each antenna group, wherein different antenna groups correspond to different calibration terminals;

[0123] or,

[0124] A calibration terminal shared by the multiple antenna groups is determined, and a 2-port channel state information reference signal for calibration is configured for the shared calibration terminal. Each of the antenna groups is calibrated in different time periods using the shared calibration terminal.

[0125] Optionally, determining the first calibration factor or the fourth calibration factor of the antenna array according to the PMI fed back by the calibration terminal corresponding to the antenna group includes:

[0126] Determining an expected calibration phase value corresponding to the antenna group according to a PMI pair fed back by a calibration terminal corresponding to the antenna group, wherein each PMI pair includes PMIs in two polarization directions;

[0127] Determining a calibration factor for the antenna group according to an expected calibration phase value corresponding to the antenna group;

[0128] A first calibration factor or a fourth calibration factor of the antenna array is determined according to the calibration factor of the antenna group.

[0129] Optionally, determining the calibration phase expected value corresponding to the antenna group according to the PMI pair fed back by the calibration terminal corresponding to the antenna group includes:

[0130] Determining a calibration phase difference coefficient for each PMI pair based on the PMI pairs fed back by each calibration terminal corresponding to the antenna group within a specific time period;

[0131] According to the calibration phase difference coefficient of each PMI pair, an expected calibration phase value corresponding to the antenna group is determined.

[0132] Optionally, determining the calibration phase expected value corresponding to the antenna group according to the calibration phase difference coefficient of each PMI pair includes:

[0133] Performing a time-based Kalman filter process on the calibration phase difference coefficient of each of the PMI pairs to determine the calibration phase expected value;

[0134] or,

[0135] According to the signal-to-noise ratio corresponding to each terminal, weighted averaging the calibration phase difference coefficients of the PMI pairs fed back by each terminal to determine the calibration phase expected value;

[0136] or,

[0137] The calibrated phase difference coefficient of any of the PMI pairs is one of the preset phase difference coefficients. According to the calibrated phase difference coefficient of each of the PMI pairs, the probability of each of the preset phase difference coefficients occurring within the specific time length is determined, and the preset phase difference coefficients are weighted and summed according to the probability of each of the preset phase difference coefficients occurring within the specific time length to obtain the expected value of the calibrated phase.

[0138] Optionally, determining the first calibration factor or the fourth calibration factor of the antenna array according to the PMI fed back by the calibration terminal corresponding to the antenna group includes:

[0139] Determine, within a specific time period, a calibration phase difference for each PMI pair based on the PMI pairs fed back by the calibration terminal corresponding to the antenna group at the current moment, wherein each PMI pair includes PMIs in two polarization directions;

[0140] Determining an expected phase difference value corresponding to the antenna group at a current moment according to the calibrated phase difference of each PMI pair;

[0141] Determining a calibration error coefficient corresponding to the antenna group at the current moment according to an expected phase difference value corresponding to the antenna group at the current moment;

[0142] If the calibration error coefficient corresponding to the antenna group at the current moment converges, determining the calibration factor of the antenna group according to the calibration error coefficient corresponding to the antenna group at the current moment;

[0143] A first calibration factor or a fourth calibration factor of the antenna array is determined according to the calibration factor of the antenna group.

[0144] Optionally, determining an expected phase difference value corresponding to the antenna group at a current moment according to the calibrated phase difference of each PMI pair includes:

[0145] Determining, based on the calibration phase difference of each of the PMI pairs, a probability of occurrence of the calibration phase difference of each of the PMI pairs at a current moment;

[0146] According to the probability of occurrence of the calibrated phase difference of each PMI at the current moment, the calibrated phase difference of each PMI pair is weighted and summed to obtain the expected phase difference value corresponding to the antenna group at the current moment.

[0147] Optionally, if the calibration error coefficient corresponding to the antenna group at the current moment converges, before determining the calibration factor of the antenna group according to the calibration error coefficient corresponding to the antenna group at the current moment, the method further includes:

[0148] If the difference between the calibration error coefficient corresponding to the antenna group at the current moment and the calibration error coefficient corresponding to the antenna group at the previous moment is within a preset range, it is determined that the calibration error coefficient corresponding to the antenna group at the current moment converges.

[0149] Optionally, determining the calibration error coefficient corresponding to the antenna group at the current moment according to the expected phase difference value corresponding to the antenna group at the current moment further includes:

[0150] Smoothing the expected phase difference value corresponding to the antenna group at the current moment and the expected phase difference value corresponding to the antenna group at the previous moment to obtain a smoothed expected phase difference value;

[0151] A calibration error coefficient corresponding to the antenna group at a current moment is determined according to the smoothed expected phase difference value.

[0152] Optionally, configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group includes:

[0153] Two sets of 2-port channel state information reference signals are configured for the calibration terminal corresponding to the antenna group, wherein each set of channel state information reference signals is mapped to an antenna in one polarization direction, and two different sets of channel state information reference signals are mapped to antennas in different polarization directions.

[0154] Optionally, configuring a 2-port channel state information reference signal for calibration for a calibration terminal corresponding to the antenna group includes:

[0155] A set of 2-port channel state information reference signals is configured for the calibration terminal corresponding to the antenna group. The set of 2-port channel state information reference signals is mapped to antennas with different polarization directions in different time periods using a time division multiplexing method.

[0156] Optionally, determining a new calibration factor of the antenna array according to the channel state information fed back by the calibration terminal includes:

[0157] determining a new calibration factor of the antenna array on the broadband according to the channel state information fed back by the calibration terminal based on the broadband;

[0158] or,

[0159] A new calibration factor of the antenna array on each subband is determined according to the channel state information fed back by the calibration terminal based on each subband.

[0160] Optionally, after determining a new calibration factor of the antenna array on each subband according to the channel state information fed back by the calibration terminal based on each subband, the method further includes:

[0161] A smoothing process is performed on the new calibration factor of the antenna array in each sub-band.

[0162] Optionally, calibrating the antenna array according to the new calibration factor includes:

[0163] Smoothing the calibration factor currently used by the array antenna and the new calibration factor to obtain a revised calibration factor;

[0164] The antennas in the antenna array are calibrated using the corrected calibration factors.

[0165] In another aspect, the present application provides an antenna calibration device, comprising:

[0166] A transceiver unit, configured to transmit a downlink channel state information reference signal to the calibration terminal via an antenna array;

[0167] an antenna calibration unit, configured to determine a new calibration factor of the antenna array based on the channel state information fed back by the calibration terminal;

[0168] A calibration execution unit is configured to calibrate the antenna array according to the new calibration factor.

[0169] On the other hand, the present application provides a processor-readable storage medium, wherein the processor-readable storage medium stores a computer program, and the computer program is used to enable the processor to execute any of the methods described above.

[0170] On the other hand, the present application provides a computer program product, comprising a computer program, wherein the computer program implements any of the above methods when executed by a processor.

[0171] The antenna calibration method, apparatus, device, storage medium and program product provided in the present application transmit a downlink channel state information reference signal to a calibration terminal through an antenna array, and determine a new calibration factor of the antenna array based on the channel state information fed back by the calibration terminal. Antenna calibration can be implemented based on air interface feedback without the need for a hardware calibration network. It can better implement antenna array calibration and improve downlink transmission performance while effectively reducing calibration costs.

[0172] It should be understood that the contents described in the above summary of the invention are not intended to limit the key or important features of the embodiments of the present application, nor are they intended to limit the scope of the present application. Other features of the present application will become easier to understand through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0173] In order to more clearly illustrate the technical solutions in the present application or the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0174] Figure 1 An example diagram of a calibration estimation path provided by an embodiment of the present application;

[0175] Figure 2 A flow chart of a method for antenna calibration provided in one embodiment of the present application;

[0176] Figure 3a A schematic diagram of the structure of four antennas provided in one embodiment of the present application;

[0177] Figure 3b A schematic diagram of the structure of an 8-antenna system according to an embodiment of the present application;

[0178] Figure 3c A schematic diagram of another structure of eight antennas provided in one embodiment of the present application;

[0179] Figure 4 A flow chart of a method for antenna calibration provided in another embodiment of the present application;

[0180] Figure 5 A flow chart of a method for antenna calibration provided in another embodiment of the present application;

[0181] Figure 6 A flow chart of a method for antenna calibration provided in another embodiment of the present application;

[0182] Figure 7 A flow chart of a method for antenna calibration provided in another embodiment of the present application;

[0183] Figure 8 A schematic structural diagram of an antenna calibration device provided in one embodiment of the present application;

[0184] Figure 9 A schematic diagram of the structure of an antenna calibration device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0185] In this application, the term "and / or" describes the relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally indicates that the associated objects are in an "or" relationship. In the embodiments of this application, the term "plurality" refers to two or more, and other quantifiers are similar.

[0186] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0187] Conventional antenna calibration involves hardware self-calibration of the antenna array. This requires calibration network hardware, which, while highly accurate, comes at a high cost. When the number of antennas to be calibrated is small, the spatial granularity of the precoding matrix is ​​large, and the gains from precise calibration may be offset by precoding quantization losses. This makes hardware self-calibration unnecessary and wastes calibration costs.

[0188] When performing hardware self-calibration on the antenna, the network device needs to have a dedicated calibration path and use the calibration path to calibrate the transmitting and receiving antennas respectively. For example, taking downlink transmission calibration as an example, the calibration estimation path for hardware self-calibration can be as follows Figure 1 As shown below. Figure 1 , the functions of each part of the calibration estimation path are described as follows:

[0189] Internal calibration loop: The calibration sequence passes through the active channel A (such as active devices such as PA (power amplifier), passive channel C (coupling channel) and active channel D (calibration channel, shared by all channels to be measured) and reaches the calibration estimation module. The calibration estimation module estimates the amplitude and phase characteristics of the integrated channels A+C+D to obtain the internal calibration factor C inner , the internal calibration factor is equivalent to the characteristics of the integrated channel (-ACD).

[0190] External calibration loop: Use the send calibration sequence, pass through active channel A, passive channel B (such as passive filters, antenna elements, etc.), and transmit via OTA (Over-the-Air Technology) to the receiving probe and then connect to the test instrument. The test instrument receives signals from multiple channels (at least two channels) simultaneously, estimates the phase (and / or amplitude) difference between the channels, and the measurement result is the amplitude and phase characteristics of channels BC, thereby obtaining the external calibration factor C. outer , which is equivalent to the characteristic of (-B+C).

[0191] Combined calibration factor: Combine the internal calibration factor C inner and external calibration factor C outer The results are combined to obtain the joint calibration factor C AC，tot :C AC，tot =C inner ·C outer , the equivalent channel is (-ACD) + (-B + C) = (-ABD). This means the joint calibration factor compensates for the differences between channels (A + B) and also introduces the characteristics of channel D. Since calibration channel D is a common channel, it does not introduce differences between channels and therefore does not affect the calibration effect.

[0192] The advantages of the hardware self-calibration solution are high accuracy and little impact from the air interface propagation environment. The disadvantage is high cost, which affects product competitiveness.

[0193] Generally, if the hardware stability of each channel is good and the variation range is small, the phase difference of different RBs (or other resolutions) between each channel can be obtained through factory testing, and the fixed calibration factor of each channel can be calculated and stored to calibrate and compensate the antenna.

[0194] While factory calibration doesn't require a hardware calibration network, it's also relatively expensive because the calibration factors are strongly dependent on the hardware device characteristics and must be tested for each product. Furthermore, factory calibration coefficients are a one-time test, making the effects uncontrollable when calibration errors vary with external conditions.

[0195] The present application provides a method, apparatus, device, storage medium, and program product for antenna calibration, which implements antenna calibration based on air interface feedback and does not require a hardware calibration network. It can effectively reduce calibration costs while better implementing antenna array calibration and improving downlink transmission performance.

[0196] Among them, the method and the device are based on the same application concept. Since the principles of solving problems by the method and the device are similar, the implementation of the device and the method can refer to each other, and the repeated parts will not be repeated.

[0197] Figure 2 A flowchart of a method for antenna calibration provided in one embodiment of the present application. The method execution subject of the embodiment of the present application can be a network device or other device for performing antenna calibration. This embodiment uses a network device as an example for illustrative purposes and is not specifically limited here.

[0198] like Figure 2 As shown, the specific steps of this method are as follows:

[0199] Step S101: Transmit a downlink channel state information reference signal to a calibration terminal via an antenna array.

[0200] The antenna array refers to the antenna array of the antenna to be calibrated.

[0201] The calibration terminal refers to a terminal device used to calibrate the antenna array, and multiple calibration terminals can be selected according to pre-set rules.

[0202] In this embodiment, the antenna array is calibrated based on CSI (Channel State Information) feedback.

[0203] First, the network device transmits a downlink channel state information reference signal to the calibration terminal through the antenna array to be calibrated, so that the calibration terminal can feed back CSI to the network device.

[0204] Step S102: Determine a new calibration factor of the antenna array according to the channel state information fed back by the calibration terminal.

[0205] The network device trains the calibration error factors between antennas based on the CSI fed back by the calibration terminal to estimate the calibration factors of the antennas.

[0206] For example, there are at least three ways to use CSI feedback to perform antenna calibration:

[0207] A first possible approach is a calibration solution based on PMI (Precoding Matrix Index) feedback: PMI feedback is used to calibrate the antenna and determine a calibration factor of the antenna array.

[0208] The second possible approach is a calibration scheme using a CQI (Channel Quality Indicator) blind test: the network device blindly tests multiple sets of calibration factors and uses CSI feedback to determine which set of calibration factors is better.

[0209] A third possible approach is to combine the first possible approach and the second possible approach, calibrating the antenna array twice using each of the two approaches to determine a final calibration factor. The order of the two approaches is not specifically limited.

[0210] For example, a first calibration may be performed based on PMI feedback, and a smaller number of calibration factor combinations may be determined based on the result of the first calibration. Then, a smaller number of CQI blind tests may be used to determine the final calibration factors, thereby improving calibration accuracy.

[0211] Step S103: calibrate the antenna array according to the new calibration factor.

[0212] After the new calibration factor of the antenna array is determined, the antenna array is calibrated based on the new calibration factor.

[0213] The embodiment of the present application transmits a downlink channel state information reference signal to the calibration terminal through the antenna array, and determines a new calibration factor of the antenna array based on the channel state information fed back by the calibration terminal. It can implement antenna calibration based on air interface feedback, does not require a hardware calibration network, and can better implement antenna array calibration while effectively reducing calibration costs, thereby improving downlink transmission performance.

[0214] Figure 4 This is a flow chart of a method for antenna calibration provided in another embodiment of the present application. Figure 2 On the basis of the corresponding embodiment, this embodiment provides a calibration scheme based on PMI feedback, wherein the channel state information includes PMI, and the PMI includes information on the phase difference of antennas in the same polarization direction. According to the channel state information fed back by the calibration terminal, a new calibration factor of the antenna array is determined, including: determining the first calibration factor of the antenna array according to the PMI fed back by the calibration terminal.

[0215] In this embodiment, the difference in phase differences between the two polarized antenna arrays is calculated, so that the phases of the antenna arrays in the two polarized directions tend to be aligned after compensation, thereby improving the codebook shaping gain.

[0216] Because the overhead and complexity of air interface calibration increase significantly with the number of antenna ports, it is more appropriate to perform air interface calibration with a smaller number of antennas. The antenna calibration method provided in this embodiment can be applied to 4TR (Transmitter and Receiver) and 8TR dual-polarized antenna array scenarios, with a one-to-one mapping between physical antennas and antenna ports.

[0217] For example, the FDD (Frequency Division Duplexing) 4TR base station antenna structure is as follows: Figure 3a As shown, the FDD 8TR base station antenna structure is as follows Figure 3b and Figure 3c shown. Figure 3a , Figure 3b and Figure 3c In the figure, antenna 0 and antenna 1, antenna 2 and antenna 3, antenna 4 and antenna 5, antenna 6 and antenna 7 are each a group of orthogonally polarized antennas.

[0218] The antenna calibration method proposed in this application is based on air interface feedback. It mainly uses the downlink CSI-RS (CSI Reference Signals) to extract the corresponding phase information from the calibration terminal measurement feedback information, and uses the results of multiple extractions to statistically train the calibration coefficients to perform antenna calibration and determine the calibration factor of the antenna array.

[0219] The CSI-RS in the 5G protocol is designed to be specific only to the port number. To use CSI-RS for antenna calibration, a one-to-one correspondence is established between physical antennas and CSI-RS port numbers. This ensures that the optimal PMI information returned by the calibration terminal carries the necessary information for calibration.

[0220] For example, taking the calibration of 4 antennas as an example, the network device can configure two groups of 2-port CSI-RS for the calibration terminal, each group corresponding to one polarization direction. Figure 3a In the antenna array shown, the first two-port CSI-RS set corresponds to physical antennas 0 and 2, while the second two-port CSI-RS set corresponds to physical antennas 1 and 3. These two CSI-RS sets are transmitted using frequency division and on the same symbol. The terminal feeds back two corresponding PMIs, corresponding to the phase difference between the two co-polarized antennas (one PMI corresponds to the phase difference between antennas 0 and 2, and the other PMI corresponds to the phase difference between antennas 1 and 3), for channel calibration.

[0221] Structurally, a single-stream codebook vector consists of two halves, one for each polarization. If there are no antenna calibration errors, the antennas in these two polarizations are physically located in the same direction, so the channels they experience differ by only a specific unknown angle. This angle is covered by the four-port PMI feedback parameters, requiring the phase difference within the two polarizations to be aligned.

[0222] For example, the 2-port codebook index is shown in Table 1 below:

[0223] Table 1

[0224]

[0225] In the embodiment of the present application, a single-stream (i.e., stream number 1) codebook is used for antenna calibration. Based on Table 1 above, it can be determined that single-stream PMI values ​​of 0, 1, 2, and 3 correspond to phase differences of 0, 90, 180, and 270 degrees between the two antennas in the same polarization direction, respectively.

[0226] like Figure 4 As shown, the antenna calibration method provided in this embodiment has the following specific steps:

[0227] Step S201: When a first calibration trigger condition is met, an antenna group corresponding to the antenna array is determined according to the number of antennas included in the antenna array, wherein each antenna group includes two polarized antenna pairs.

[0228] The first calibration trigger condition is used to define the timing for initiating antenna calibration based on PMI feedback. It can be set and adjusted based on the needs of the actual application scenario and is not specifically limited here. For example, the first calibration trigger condition can be the arrival of the next calibration cycle or the arrival of a pre-set calibration time.

[0229] In this embodiment, the network device selects multiple calibration terminals for antenna calibration within a specific time period according to certain selection rules.

[0230] For example, a terminal device with a relatively high SNR (signal-to-noise ratio), a relatively slow moving speed, and a relatively low interference level near a base station within a cell can be selected as a calibration terminal. Furthermore, the selection rules for selecting the calibration terminal can be configured and adjusted based on the needs of the actual application scenario and are not specifically limited here.

[0231] In this embodiment, if the antenna array to be calibrated contains more than four antennas, the antenna array can be divided into multiple antenna groups, each containing four antennas that form two polarized antenna pairs. Each of the four antennas in each antenna group is then calibrated separately to determine the calibration factor for each antenna group. If necessary, inter-antenna group calibration is performed based on the calibration factor for each antenna group to determine the calibration factor for the antenna array.

[0232] Specifically, if the antenna array includes four antennas and the four antennas form two polarized antenna pairs, the four antennas are regarded as an antenna group, and a calibration terminal corresponding to the antenna group is determined. The calibration terminal is a terminal used to calibrate the antenna group.

[0233] If the antenna array has more than four antennas, split the antenna array into multiple antenna groups. Each antenna group contains two polarized antenna pairs. Use any polarized antenna pair as a reference antenna pair. Use multiple antenna groups to directly or indirectly associate any polarized antenna with the reference antenna pair.

[0234] Among them, if any polarized antenna pair and the reference antenna are in the same antenna group, it is determined that the any polarized antenna pair is directly associated with the reference antenna; if any polarized antenna pair and the reference antenna pair are not in the same antenna group, and any polarized antenna and the reference antenna are both directly associated with the first antenna pair, it is determined that the any polarized antenna is indirectly associated with the reference antenna; if any polarized antenna is indirectly associated with the second antenna pair, and the second antenna pair is indirectly associated with the reference antenna pair, it is determined that the any polarized antenna is indirectly associated with the reference antenna pair.

[0235] In this embodiment, direct association and indirect association are used to describe the association relationship between two polarized antenna pairs. If the two polarized antenna pairs are in the same antenna group, the two polarized antenna pairs are directly associated.

[0236] If two antenna pairs are not directly associated, the two antenna pairs may be indirectly associated through one or more other antenna pairs.

[0237] Exemplarily, if the first antenna pair and the second antenna pair are not in the same antenna group, and the first antenna pair and the third antenna pair are in the same antenna group, and the second antenna pair and the third antenna pair are in the same antenna group, then the first antenna pair and the second antenna pair are indirectly associated through the third antenna pair.

[0238] Furthermore, if the first antenna pair and the second antenna pair are indirectly associated through the third antenna pair, and another fourth antenna pair is not directly associated with the first antenna pair, but the fourth antenna pair is directly associated with the second antenna pair, then the fourth antenna pair is also indirectly associated with the first antenna pair, and the fourth antenna pair is associated with the first antenna pair through the second antenna pair and the third antenna pair.

[0239] In addition, the two antenna pairs may be indirectly associated through three or more other antenna pairs, which are not listed one by one in this embodiment.

[0240] When the number of actual antennas exceeds the number of ports, it is impossible to perform precise calibration down to the antenna channel level; calibration must be performed on a port-by-port basis. The number of antenna groups an antenna array can be divided into can be determined based on the number of ports. Grouping an antenna array is essentially grouping ports. Assuming the number of ports in an antenna array is N, the ports can be divided into (N / 2-1) groups. Grouping can be performed in a variety of ways, ensuring that any polarized antenna pair is directly or indirectly associated with a reference antenna pair, thereby enabling inter-group calibration based on the reference antenna pair.

[0241] In addition, the antenna calibration solution provided in this application is more practical for base stations that use no more than the preset number of antennas (such as 4-antenna or 8-antenna base stations). Generally speaking, when the number of antennas is large, such as 16, 32, or 64, in order to obtain better shaping gain, the base station should also have a hardware calibration network to improve calibration accuracy through hardware self-calibration. The preset number of antennas can be set and adjusted according to the needs of the actual application scenario. For example, the preset number of antennas can be 8. This embodiment does not specifically limit the number of preset antennas.

[0242] In an optional implementation, the antenna array is divided into multiple antenna groups, any polarized antenna pair is used as a reference antenna pair, and each antenna group includes a reference antenna pair.

[0243] For example, taking the antenna array including 8 antennas as an example, for Figure 3b or Figure 3c The antenna array shown can be divided into three antenna groups: {0, 1, 2, 3}, {0, 1, 4, 5}, and {0, 1, 6, 7}. Antenna pair {0, 1} is used as the reference antenna pair and is included in all three antenna groups. Antenna pairs {2, 3}, {4, 5}, and {6, 7} are directly associated with the reference antenna pair.

[0244] In addition, other grouping methods can be used, for example, Figure 3b or Figure 3cThe antenna array shown can also be divided into the following three antenna groups: {0, 1, 2, 3}, {4, 5, 6, 7}, and {0, 1, 4, 5}. Antenna pair {0, 1} is used as the reference antenna pair. Antenna pair {4, 5} and the reference antenna pair are in the same antenna group, and antenna pair {4, 5} is directly associated with the reference antenna pair. Antenna pair {6, 7} and the reference antenna pair are not in the same antenna group, so antenna pair {6, 7} and the reference antenna pair are not directly associated. Antenna pair {6, 7} and the reference antenna pair are both directly associated with antenna pair {4, 5}, so antenna pair {6, 7} and the reference antenna pair are indirectly associated. Thus, although the first two groups do not intersect (the same antenna pair), the third group contains one polarized antenna pair from each of the first two groups, enabling inter-group calibration.

[0245] In this embodiment, after determining one or more antenna groups corresponding to the antenna array, four antennas are calibrated for each antenna group to obtain a calibration factor corresponding to each antenna group; further, based on the calibration factor corresponding to each antenna group, the calibration factor corresponding to the entire antenna array can be determined.

[0246] Step S202: Determine the calibration terminal corresponding to the antenna group, and configure a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group.

[0247] In this embodiment, in order to implement calibration of four antennas for each antenna group, it is necessary to determine a calibration terminal corresponding to each antenna group and configure at least one set of 2-port channel state information reference signals for calibration for the calibration terminal corresponding to the antenna group.

[0248] An optional implementation of this step is:

[0249] A corresponding calibration terminal is determined for each antenna group, and a 2-port channel state information reference signal for calibration is configured for the calibration terminal corresponding to each antenna group, wherein different calibration terminals correspond to different antenna groups.

[0250] In this implementation, by selecting a different calibration terminal for each antenna group and configuring a 2-port channel state information reference signal (CSI) for calibration, calibration of different antenna groups can be performed using different calibration terminals. This allows for slow changes in antenna calibration factors over a specific calibration timeframe and allows for statistical training. For example, multiple 2-port CSI-RS groups (e.g., 3 groups) can be allocated, with each antenna group corresponding to one 2-port CSI-RS group.

[0251] Another optional implementation of this step is:

[0252] A calibration terminal shared by multiple antenna groups is determined, and a 2-port channel state information reference signal for calibration is configured for the shared calibration terminal. Each antenna group is calibrated using the shared calibration terminal in different time periods.

[0253] In this implementation, multiple antenna groups share a calibration terminal, which is used to calibrate each antenna group at different time periods. When there are too many antenna groups, calibrating each antenna group sequentially takes a long time. It is necessary to ensure that the antenna calibration factors change slowly enough to be trained and counted within the specified calibration time. Thus, two shared sets of 2-port CSI-RS are allocated for antenna calibration, and different antenna groups are mapped to these two sets of 2-port CSI-RS at different times.

[0254] The specific time length refers to the maximum time that is preset for performing a calibration of the antenna array. This can be set and adjusted based on the actual application scenario and is not specifically limited here. For example, the maximum time for performing an antenna calibration can be preset to 1 minute, 30 seconds, 2 minutes, etc.

[0255] In this embodiment, when configuring a 2-port CSI reference signal for calibration for the calibration terminals corresponding to the antenna group, two additional 2-port CSI-RS sets can be configured for the set of calibration terminals, with each CSI-RS set mapped to an antenna pair with the same polarization direction. Alternatively, only one additional 2-port CSI-RS set can be configured and mapped to two antenna pairs with different polarizations using time division multiplexing.

[0256] Optionally, two sets of 2-port channel state information reference signals are configured for the calibration terminal corresponding to the antenna group, where each set of channel state information reference signals is mapped to an antenna in a polarization direction, and two different sets of channel state information reference signals are mapped to antennas in different polarization directions.

[0257] Optionally, a set of 2-port channel state information reference signals is configured for the calibration terminal corresponding to the antenna group. Using time division multiplexing, the set of 2-port channel state information reference signals is mapped to antennas with different polarization directions in different time periods.

[0258] In this embodiment, before transmitting a downlink channel state information reference signal to a calibration terminal through an antenna array, through steps S201-S202, when the number of antennas contained in the antenna array exceeds a preset number of antennas, the antenna array is split into multiple antenna groups of 4 antennas, the calibration terminal corresponding to the antenna group is determined, and a 2-port channel state information reference signal for calibration is configured for the calibration terminal corresponding to the antenna group.

[0259] Step S203: Transmit a downlink channel state information reference signal to the calibration terminal through the antenna array.

[0260] The network device transmits a downlink channel state information reference signal to the calibration terminal through the antenna array to be calibrated, so that the calibration terminal can feed back the PMI to the network device.

[0261] Step S204: Determine a first calibration factor of the antenna array according to the PMI fed back by the calibration terminal, where the first calibration factor is a new calibration factor of the antenna array.

[0262] In this embodiment, the first calibration factor represents a calibration factor of the antenna array determined based on the fed-back PMI.

[0263] In an optional implementation of this embodiment, this step can be implemented through the following steps a1-a3:

[0264] Step a1: Determine the calibration phase expected value corresponding to the antenna group according to the PMI pair fed back by the calibration terminal corresponding to the antenna group, where each PMI pair includes PMIs in two polarization directions.

[0265] Each antenna group includes two polarization antenna pairs (eg, antenna pair {0, 1} and antenna pair {2, 3}).

[0266] Furthermore, based on the PMI pair fed back by the calibration terminal corresponding to the antenna group, the calibration phase expected value corresponding to the antenna group is determined, which can be achieved in the following manner:

[0267] Within a specific time length, the calibration phase difference coefficient of each PMI pair is determined based on the PMI pair fed back by each calibration terminal corresponding to the antenna group; and the calibration phase expected value corresponding to the antenna group is determined based on the calibration phase difference coefficient of each PMI pair.

[0268] For example, the calibration terminal of the antenna group is configured with two sets of 2-port CSI-RS, and each set of CSI-RS is mapped to an antenna pair with the same polarization direction. Assume that any antenna group corresponds to I calibration terminals, and each PMI pair fed back by the i-th calibration terminal at time t includes PMIs in two polarization directions, which can be expressed as pmi1 i，t (corresponding to antenna 0,2) and pmi2 i，t (Antenna 1,3).

[0269] The calibration phase difference coefficient of each PMI pair can be calculated using the following formula 1:

[0270]

[0271] Among them, c i，t represents the calibration phase difference coefficient of the PMI pair fed back by the i-th calibration terminal at time t. j is an imaginary unit. mod is the modulo operation.

[0272] Based on Formula 1, it can be determined that the calibration phase difference coefficient of the PMI pair has four possible values.

[0273] Within a specific time length of a calibration, if the calibration phase difference coefficients of the PMI pairs fed back by I UE at multiple different times (0-T) constitute a data set C I，T ={c i，t |i=0,…,I,t=0,…,T}. For set C I，T Perform statistics and use function f() to represent statistical processing, and finally obtain a relatively accurate calibration phase expected value cexp=f(C I，T ).

[0274] Among them, for the set C I，T There are many methods for performing statistics, which can be set and adjusted according to the needs of actual application scenarios and are not specifically limited here.

[0275] Exemplarily, a time-based Kalman filter process may be performed on the calibration phase difference coefficient of each PMI pair to determine an expected calibration phase value.

[0276] Exemplarily, the calibration phase expected value may be determined by weighted averaging of the calibration phase difference coefficients of the PMI pairs fed back by each terminal according to the signal-to-noise ratio corresponding to each terminal.

[0277] Exemplarily, the calibration phase difference coefficient of any PMI pair is one of the preset phase difference coefficients. Based on the calibration phase difference coefficient of each PMI pair, the probability of each preset phase difference coefficient occurring within a specific time length is determined, and the preset phase difference coefficients are weighted and summed based on the probability of each preset phase difference coefficient occurring within the specific time length to obtain the expected calibration phase value. The preset phase difference coefficient refers to a possible value of the calibration phase difference coefficient of the PMI pair.

[0278] Step a2: Determine the calibration factor of the antenna group according to the expected calibration phase value corresponding to the antenna group.

[0279] The expected value of the calibration phase corresponding to the antenna group is also the calibration error coefficient corresponding to the antenna group.

[0280] After determining the expected calibration phase value cexp corresponding to the antenna group, the calibration factors of the four antennas in the antenna group can be determined. The calibration vector composed of the calibration factors of the four antennas can be expressed as: [1, 1, 1, cexp] T ,in[] T Represents the transpose of a vector.

[0281] Step a3: Determine a first calibration factor of the antenna array according to the calibration factor of the antenna group.

[0282] After determining the calibration factors of the antenna groups, a first calibration factor for the antenna array may be determined based on the calibration factor of each antenna group.

[0283] If the antenna array includes four antennas, that is, the antenna array corresponds to only one antenna group, then the antenna group is also the antenna array, and the calibration factor of the antenna group is the calibration factor of the antenna array.

[0284] If the antenna array contains more than four antennas, it is divided into multiple antenna groups. Inter-group calibration is performed on these multiple antenna groups to determine the calibration factor of the antenna array. To determine the calibration factor of an antenna pair through inter-group calibration of two antenna groups, multiply the calibration factors of the two antenna groups together.

[0285] For example, an antenna array containing 8 antennas is divided into the following 3 antenna groups: {0, 1, 2, 3}, {0, 1, 4, 5}, and {0, 1, 6, 7}. The antenna pair {0, 1} is used as the reference antenna pair, and each antenna group contains the reference antenna pair {0, 1}. 4-antenna calibration is performed on each of the three antenna groups to determine the calibration phase expected values ​​cexp1, cexp2, and cexp3 corresponding to the three antenna groups. The vector of calibration factors for the antenna array can be expressed as [1, 1, 1, cexp1, 1, cexp2, 1, cexp3]. T ,in[] T Represents the transpose of a vector.

[0286] For example, an antenna array consisting of eight antennas is divided into the following three antenna groups: {0, 1, 2, 3}, {4, 5, 6, 7}, and {0, 1, 4, 5}. The antenna pair {0, 1} is used as the reference antenna pair. Four-antenna calibration is performed on each of the three antenna groups to determine the calibration phase expectation values ​​cexp1′, cexp2′, and cexp3′ corresponding to the three antenna groups. This grouping method requires an inter-group calibration for {4, 5, 6, 7} and {0, 1, 4, 5}. The resulting antenna array calibration factor can be expressed as [1, 1, 1, cexp1′, 1, cexp3′, cexp3′, cexp2′*cexp3′]. T ,in[] T Represents the transpose of a vector.

[0287] In another optional implementation of this embodiment, this step may also be implemented by iterating the following steps b1-b6 multiple times within a specific time period based on the PMI pairs fed back at each moment:

[0288] Step b1: within a specific time length, determine the calibration phase difference of each PMI pair based on the PMI pairs fed back by the calibration terminal corresponding to the antenna group at the current moment, where each PMI pair includes PMIs in two polarization directions.

[0289] For example, the calibration terminal of the antenna group is configured with two sets of 2-port CSI-RS, and each set of CSI-RS is mapped to an antenna pair with the same polarization direction. Assume that any antenna group corresponds to I calibration terminals, and each PMI pair fed back by the i-th calibration terminal at time t includes PMIs in two polarization directions, which can be expressed as pmi1 i，t (corresponding to antenna 0,2) and pmi2 i，t (Antenna 1,3).

[0290] In step b1, the calibration phase difference of each PMI pair can be calculated using the following formula 2:

[0291] δ i，t =((pmi1 i，t -pmi2 i，t )mod 4)*π / 2 Formula 2

[0292] Among them, δ i，t represents the calibration phase difference of the PMI pair fed back by the i-th calibration terminal at time t. mod is the modulo operation. Initially, δ i，0 = 0. According to Formula 2, it can be determined that the calibration phase difference of each PMI pair has four possible values.

[0293] Step b2: Determine the probability of the calibration phase difference of each PMI pair occurring at the current moment based on the calibration phase difference of each PMI pair.

[0294] According to the calibration phase difference of each PMI pair fed back at the current time t, the probability of occurrence of the calibration phase difference of each PMI pair is calculated, that is, the probabilities of the four possible values ​​of the calibration phase difference of the PMI pair.

[0295] Step b3: Based on the probability of occurrence of the calibrated phase difference of each PMI at the current moment, weighted summation is performed on the calibrated phase difference of each PMI pair to obtain the expected phase difference value corresponding to the antenna group at the current moment.

[0296] The probability of occurrence of the calibration phase difference of each PMI is used as the weight of the calibration phase difference. The following formula 3 is used to weight the calibration phase difference of each PMI pair fed back at the current time t to determine the expected phase difference value corresponding to the antenna group at the previous time:

[0297]

[0298] in, represents the expected phase difference corresponding to the antenna group at time t. I is the number of calibration terminals corresponding to the antenna group. i，t is the calibration phase difference of the PMI pair fed back by the i-th calibration terminal at time t. i，t is δ i，t The corresponding probability. Initially

[0299] Step b4: Determine the calibration error coefficient corresponding to the antenna group at the current moment based on the expected phase difference value corresponding to the antenna group at the current moment.

[0300] Optionally, the expected phase difference value corresponding to the antenna group at the current moment and the expected phase difference value corresponding to the antenna group at the previous moment are smoothed to obtain a smoothed expected phase difference value; and the calibration error coefficient corresponding to the antenna group at the current moment is determined based on the smoothed expected phase difference value.

[0301] Exemplarily, the expected phase difference value corresponding to the antenna group at the current moment and the expected phase difference value corresponding to the antenna group at the previous moment (time t-1) may be subjected to Kalman filtering to achieve smoothing processing and obtain a smoothed expected phase difference value.

[0302] Furthermore, based on the expected phase difference value corresponding to the antenna group at the previous moment, the calibration error coefficient corresponding to the antenna group at the current moment is determined by the following formula 4:

[0303]

[0304] Among them, cexp t is the calibration error coefficient corresponding to the antenna group at the current moment, is the expected phase difference corresponding to the antenna group at time t, or the expected phase difference after smoothing. j is an imaginary unit.

[0305] Step b5: If the calibration error coefficient corresponding to the antenna group at the current moment converges, determine the calibration factor of the antenna group according to the calibration error coefficient corresponding to the antenna group at the current moment.

[0306] Before step b5, if the difference between the calibration error coefficient corresponding to the antenna group at the current moment and the calibration error coefficient corresponding to the antenna group at the previous moment is within a preset range, it is determined that the calibration error coefficient corresponding to the antenna group at the current moment has converged.

[0307] For example, using cexp t Indicates the calibration error coefficient corresponding to the antenna group at the current time t, using cexp t-1 Indicates the calibration error coefficient corresponding to the antenna group at the previous moment (t-1 moment), if |cexp t -cexp t-1|<Th, indicating that the calibration error coefficient determined based on the PMI has converged. Th may be a preset error coefficient threshold, which can be set and adjusted according to the needs of the actual application scenario and will not be further described here.

[0308] If the calibration error coefficient corresponding to the antenna group at the current moment converges, the antenna group contains 4 antennas, and the calibration vector composed of the calibration factors of the 4 antennas can be expressed as: [1, 1, 1, cexp t ] T ,in[] T Represents the transpose of a vector.

[0309] If the calibration error coefficient corresponding to the antenna group at the current moment has not converged, the calibration of the antenna group may continue until the calibration error coefficient corresponding to the antenna group converges at a certain moment.

[0310] In addition, the condition for stopping iteration may also be that the number of iterations reaches a preset number, or the antenna calibration time reaches a preset specific time length, etc., which can be set and adjusted according to the actual application scenario and is not specifically limited here.

[0311] Step b6: Determine a first calibration factor of the antenna array according to the calibration factor of the antenna group.

[0312] After determining the calibration factors of the antenna groups, a first calibration factor for the antenna array may be determined based on the calibration factor of each antenna group.

[0313] If the antenna array includes four antennas, that is, the antenna array corresponds to only one antenna group, then the antenna group is also the antenna array, and the calibration factor of the antenna group is the calibration factor of the antenna array.

[0314] If the antenna array contains more than four antennas, it is divided into multiple antenna groups. Inter-group calibration is performed on these multiple antenna groups to determine the calibration factor of the antenna array. To determine the calibration factor of an antenna pair through inter-group calibration of two antenna groups, multiply the calibration factors of the two antenna groups together.

[0315] For example, an antenna array containing eight antennas is divided into the following three antenna groups: {0, 1, 2, 3}, {0, 1, 4, 5}, and {0, 1, 6, 7}. The antenna pair {0, 1} is used as the reference antenna pair, and each antenna group contains the reference antenna pair {0, 1}. Four-antenna calibration is performed on each of the three antenna groups to determine the calibration phase expected values ​​cexp1, cexp2, and cexp3 corresponding to the three antenna groups. The resulting calibration factors for the antenna array can be expressed as [1, 1, 1, cexp1, 1, cexp2, 1, cexp3]. T ,in[] T Represents the transpose of a vector.

[0316] For example, an antenna array consisting of eight antennas is divided into the following three antenna groups: {0, 1, 2, 3}, {4, 5, 6, 7}, and {0, 1, 4, 5}. The antenna pair {0, 1} is used as the reference antenna pair. Four-antenna calibration is performed on each of the three antenna groups to determine the calibration phase expectation values ​​cexp1′, cexp2′, and cexp3′ corresponding to the three antenna groups. This grouping method requires an inter-group calibration for {4, 5, 6, 7} and {0, 1, 4, 5}. The resulting antenna array calibration factor can be expressed as [1, 1, 1, cexp1′, 1, cexp3′, cexp3′, cexp2′*cexp3′]. T ,in[] T Represents the transpose of a vector.

[0317] In this embodiment, the antenna array is calibrated once through the above steps S201-S204 to obtain a new calibration factor for the antenna array. It should be noted that when calibrating the antenna array, by configuring the calibration terminal to feedback the PMI according to the broadband, antenna calibration can be performed based on broadband feedback. By configuring the calibration terminal to feedback the PMI according to the subband (narrowband), antenna calibration can be performed based on subband (narrowband) feedback. If subband feedback is configured, the antenna calibration process is executed independently for each subband. For broadband systems, the calibration error varies greatly across the entire frequency band, so calibration based on subband feedback is relatively better.

[0318] Exemplarily, calibration based on broadband feedback is to determine a new calibration factor of the antenna array in the broadband according to the PMI of the calibration terminal based on the broadband feedback.

[0319] Exemplarily, calibration based on sub-band feedback is to determine a new calibration factor of the antenna array on each sub-band according to the PMI fed back by the calibration terminal based on each sub-band.

[0320] Optionally, if calibration is performed based on subband feedback, after determining the new calibration factor of the antenna array on each subband according to the PMI fed back by the calibration terminal based on each subband, the new calibration factor of the antenna array on each subband can also be smoothed.

[0321] Step S205: calibrate the antenna array according to the new calibration factor of the antenna array.

[0322] Optionally, after the new calibration factor of the antenna array is determined, the antenna array may be calibrated directly based on the new calibration factor.

[0323] In an optional implementation of this step, after determining the new calibration factor of the antenna array, the calibration factor currently used by the array antenna and the new calibration factor can be smoothed to obtain a corrected calibration factor; and the antennas in the antenna array are calibrated using the corrected calibration factor.

[0324] Exemplarily, Kalman filtering may be performed on the calibration factor currently used by the array antenna and the new calibration factor to achieve smoothing processing and obtain a revised calibration factor.

[0325] In this embodiment, the smoothing process may be implemented using methods other than Kalman filtering, which is not specifically limited here.

[0326] An embodiment of the present application provides a solution for antenna calibration based on PMI feedback. By splitting the antenna array into antenna groups consisting of 4 antennas, calibrating each antenna group separately, determining the calibration factor corresponding to each antenna group, and further determining the calibration factor of the entire antenna array, antenna calibration based on PMI feedback is implemented. Antenna calibration can be implemented based on air interface feedback, without the need for a hardware calibration network. It can better implement antenna array calibration while effectively reducing calibration costs, thereby improving downlink transmission performance.

[0327] Figure 5 This is a flow chart of a method for antenna calibration provided in another embodiment of the present application. Figure 2 On the basis of the corresponding embodiment, this embodiment provides a calibration scheme using CQI blind testing, where the channel state information includes CQI. The new calibration factor of the antenna array is determined based on the channel state information fed back by the calibration terminal, including: determining the second calibration factor of the antenna array based on the CQI fed back by multiple calibration terminals.

[0328] like Figure 5 As shown, the specific steps of this method are as follows:

[0329] Step S301: When a second calibration trigger condition is met, a plurality of consecutive feedback cycles are determined according to a plurality of different candidate calibration factors of the antenna array, where the feedback cycles correspond to the candidate calibration factors in a one-to-one manner.

[0330] The second calibration trigger condition is used to determine when to initiate antenna calibration using a CQI blind test. This can be configured and adjusted based on the actual application scenario and is not specifically defined here. For example, the second calibration trigger condition can be the arrival of the next calibration cycle or the arrival of a pre-set calibration time.

[0331] Multiple sets of different candidate calibration factors for the antenna array can be set and adjusted according to actual application scenarios and experience, and are not specifically limited here.

[0332] In this embodiment, a calibration terminal with a slow moving speed may be selected, and the channel quality remains approximately unchanged within the observation time window.

[0333] In this step, the number of consecutive feedback cycles is the same as the number of groups of alternative calibration factors of the antenna array. The feedback cycles correspond to the alternative calibration factors one by one, and each feedback cycle is used to calibrate a corresponding group of alternative calibration factors.

[0334] Step S302: In each feedback cycle, after calibrating the antenna array using the candidate calibration factor corresponding to the feedback cycle, transmit a downlink channel state information reference signal to multiple calibration terminals through the calibrated antenna array.

[0335] In this step, within each feedback cycle, the antenna array is calibrated using the alternative calibration factor corresponding to the feedback cycle, and then CSI-RS is transmitted to multiple calibration terminals through the calibrated antenna array, so that the calibration terminals can feedback CQI to the network device within the corresponding feedback cycle.

[0336] In this embodiment, through steps S301 - S302 , a downlink channel state information reference signal is transmitted to the calibration terminal through the antenna array.

[0337] Step S303: Determine a comprehensive CQI in each feedback cycle according to the CQIs fed back by multiple calibration terminals in each feedback cycle.

[0338] In this step, the comprehensive CQI in each feedback cycle is determined by the following formula 5:

[0339] Q n =∑ i cqi i，t Formula 5

[0340] Among them, Q n is the comprehensive CQI in the nth feedback cycle. i，t represents the CQI fed back by the i-th calibration terminal at time t in the n-th feedback cycle.

[0341] Step S304: The candidate calibration factor corresponding to the feedback period with the maximum comprehensive CQI is used as the second calibration factor of the antenna array. The second calibration factor is the new calibration factor of the antenna array.

[0342] After determining the integrated CQI in each feedback cycle, the feedback cycle with the maximum integrated CQI is determined, and the candidate calibration factor corresponding to the feedback cycle with the maximum integrated CQI is used as the second calibration factor of the antenna array.

[0343] In the embodiment of the present application, the second calibration factor is used to represent the calibration factor of the antenna arrangement determined by the calibration scheme using the CQI blind test.

[0344] Through the above steps S303-S304, the second calibration factor of the antenna array is determined according to the CQIs fed back by the multiple calibration terminals.

[0345] Step S305: calibrate the antenna array according to the new calibration factor of the antenna array.

[0346] Optionally, after the new calibration factor of the antenna array is determined, the antenna array may be calibrated directly based on the new calibration factor.

[0347] In an optional implementation of this step, after determining the new calibration factor of the antenna array, the calibration factor currently used by the array antenna and the new calibration factor can be smoothed to obtain a corrected calibration factor; and the antennas in the antenna array are calibrated using the corrected calibration factor.

[0348] Exemplarily, Kalman filtering may be performed on the calibration factor currently used by the array antenna and the new calibration factor to achieve smoothing processing and obtain a revised calibration factor.

[0349] In this embodiment, the smoothing process may be implemented using methods other than Kalman filtering, which is not specifically limited here.

[0350] In another implementation of this embodiment, the CRI (CSI-RS Resource Indicator) fed back by the calibration terminal can also be used to perform antenna calibration, and blind testing and selection of multiple groups of alternative calibration factors can be performed, which is similar to the calibration scheme based on CQI blind testing and will not be repeated here.

[0351] An embodiment of the present application provides a solution for antenna calibration using CQI blind testing. When a second calibration trigger condition is met, multiple consecutive feedback cycles are determined based on multiple groups of different alternative calibration factors for the antenna array, and the feedback cycles correspond to the alternative calibration factors one-to-one. In each feedback cycle, the antenna array is calibrated using the alternative calibration factor corresponding to the feedback cycle, and then CSI-RS is transmitted to multiple calibration terminals through the calibrated antenna array. Based on the CQI fed back by multiple calibration terminals in each feedback cycle, the comprehensive CQI in each feedback cycle is determined. The alternative calibration factor corresponding to the feedback cycle with the largest comprehensive CQI is used as the second calibration factor for the antenna array to implement antenna calibration based on PMI feedback. Antenna calibration can be implemented based on air interface feedback, without the need for a hardware calibration network, and can better implement antenna array calibration while effectively reducing calibration costs, thereby improving downlink transmission performance.

[0352] Figure 6A flowchart of a method for antenna calibration provided in another embodiment of the present application. Based on any of the above embodiments, in this embodiment, the antenna array can be first calibrated using a calibration scheme based on PMI feedback, and then further calibrated using a calibration scheme using a CQI blind test to obtain a new calibration factor for the antenna array after the secondary calibration.

[0353] like Figure 6 As shown, the specific steps of this method are as follows:

[0354] Step S401: When a first calibration trigger condition is met, an antenna group corresponding to the antenna array is determined according to the number of antennas included in the antenna array, wherein each antenna group includes two polarized antenna pairs.

[0355] Step S402: Determine a calibration terminal corresponding to the antenna group, and configure at least one set of 2-port channel state information reference signals for calibration for the calibration terminal corresponding to the antenna group.

[0356] Step S403: Transmit a downlink channel state information reference signal to the calibration terminal through the antenna array.

[0357] Step S404: Determine a first calibration factor of the antenna array according to the PMI fed back by the calibration terminal.

[0358] The above steps S401-S404 are the process of antenna calibration based on PMI feedback, which is similar to the above Figure 4 The process of determining the first calibration factor of the antenna array in steps S201 to S204 in the corresponding embodiment is the same and will not be repeated here.

[0359] In this embodiment, after the antenna is calibrated through a calibration scheme based on PMI feedback and the first calibration factor of the antenna array is determined, steps S406-S409 are used to determine multiple groups of different alternative calibration factors for the antenna array based on the first calibration factor of the antenna array, and the antenna array is further calibrated using a CQI blind test to obtain a new calibration factor of the antenna array after the secondary calibration, thereby further improving the accuracy of the antenna calibration and enhancing the downlink transmission performance.

[0360] Step S405: Determine multiple groups of different candidate calibration factors for the antenna array according to the first calibration factor of the antenna array.

[0361] In this embodiment, multiple groups of different candidate calibration factors for the antenna array are determined based on calibration factors determined by calibrating the antenna array based on PMI feedback, which can greatly narrow the range of candidate calibration factors.

[0362] Step S406: Determine a plurality of consecutive feedback cycles according to the multiple groups of different candidate calibration factors of the antenna array, where the feedback cycles correspond one to one with the candidate calibration factors.

[0363] Step S407: In each feedback cycle, after calibrating the antenna array using the candidate calibration factor corresponding to the feedback cycle, transmit a downlink channel state information reference signal to multiple calibration terminals through the calibrated antenna array.

[0364] Step S408: Determine a second calibration factor of the antenna array according to the CQIs fed back by the multiple calibration terminals, where the second calibration factor is a new calibration factor of the antenna array.

[0365] Step S409: calibrate the antenna array according to the new calibration factor of the antenna array.

[0366] After determining multiple sets of different candidate calibration factors for the antenna array, the specific implementation of steps S406-S409 is the same as above. Figure 5 The specific implementation of steps S301-S305 in the corresponding embodiment is similar and will not be repeated here.

[0367] For example, for the calibration of 4 antennas, assuming that 3 groups of 2-port alternative calibration factors are set, they can be set to [1 1] T 、 [1e -j*π / 8 ] T For the polarization antenna pair consisting of antennas 0 and 2, assuming that the CQI statistics show e j*π / 8 The corresponding CQI statistical value Q2 is the largest; and the polarization antenna pair composed of antennas 1 and 3, assuming that the statistical results show e -j*π / 8 The corresponding CQI statistic Q3 is the largest. Then the calibration vector on the current subband of the corresponding 4 antennas is [1,e j *π / 8 ,1,cexp t *e j*-π / 8 ] T , where cexp t is the calibration error coefficient of the four antennas determined based on the PMI feedback calibration, where [] T Represents the transpose of a vector.

[0368] In this embodiment, antenna calibration is performed through steps S401-S404 using a calibration scheme based on PMI feedback. PMI is used to align the relative error angles in both polarization directions. Antenna calibration is then performed using a blind CQI test. Calibration accuracy is improved by finding a more accurate set of multiple two-port candidate calibration factors within both polarization directions using CQI feedback.

[0369] In this embodiment, antenna calibration is first performed using a calibration scheme based on PMI feedback to determine a first calibration factor for the antenna array. Based on this first calibration factor, multiple sets of candidate calibration factors are then determined. The antenna array is further calibrated using a CQI blind test to obtain new calibration factors for the antenna array after secondary calibration. This further improves antenna calibration accuracy and enhances downlink transmission performance.

[0370] Figure 7 A flowchart of a method for antenna calibration provided in another embodiment of the present application. Based on any of the above embodiments, in this embodiment, the antenna array can be first calibrated using a calibration scheme using a CQI blind test, and then further calibrated using a calibration scheme based on PMI feedback to obtain a new calibration factor for the antenna array after the secondary calibration.

[0371] like Figure 7 As shown, the specific steps of this method are as follows:

[0372] Step S501: When a second calibration trigger condition is met, a plurality of consecutive feedback cycles are determined according to a plurality of different candidate calibration factors of the antenna array, where the feedback cycles correspond to the candidate calibration factors in a one-to-one manner.

[0373] Step S502: In each feedback cycle, after calibrating the antenna array using the candidate calibration factor corresponding to the feedback cycle, a downlink channel state information reference signal is transmitted to multiple calibration terminals through the calibrated antenna array.

[0374] Step S503: Determine a comprehensive CQI in each feedback cycle according to the CQIs fed back by multiple calibration terminals in each feedback cycle.

[0375] Step S504: Use the candidate calibration factor corresponding to the feedback period with the maximum comprehensive CQI as the second calibration factor of the antenna array.

[0376] The above steps S501-S504 are the process of antenna calibration using CQI blind test, which is similar to the above Figure 5 The process of determining the second calibration factor of the antenna array in steps S301 to S304 in the corresponding embodiment is the same and will not be repeated here.

[0377] In this embodiment, after performing antenna calibration by using the antenna calibration scheme of the CQI blind test to determine the second calibration factor of the antenna array, the antenna array can be further calibrated based on the PMI feedback through steps S505-S509 to obtain a new calibration factor of the antenna array after the second calibration, thereby further improving the accuracy of the antenna calibration and enhancing the downlink transmission performance.

[0378] Step S505: Determine antenna groups corresponding to the antenna array according to the number of antennas included in the antenna array, where each antenna group includes two polarized antenna pairs.

[0379] This step is the same as Figure 4 The implementation of step S201 in the corresponding embodiment is similar and will not be repeated here.

[0380] Step S506: Determine the calibration terminal corresponding to the antenna group, and configure a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group.

[0381] This step is the same as Figure 4 The implementation of step S202 in the corresponding embodiment is similar and will not be repeated here.

[0382] Step S507: Transmit a downlink channel state information reference signal to a calibration terminal corresponding to the antenna group through the antenna group according to the second calibration factor of the antenna array.

[0383] In this embodiment, Figure 4 The implementation of step S203 in the corresponding embodiment is different. In step S507, the antenna array is first calibrated according to the second calibration factor of the antenna array, and then the CSI-RS is transmitted to the corresponding calibration terminal through the antenna array.

[0384] Step S508: Determine a first calibration factor of the antenna array according to the PMI fed back by the calibration terminal corresponding to the antenna group. The first calibration factor is a new calibration factor of the antenna array.

[0385] This step is the same as Figure 4 The implementation of step S204 in the corresponding embodiment is similar and will not be repeated here.

[0386] Step S509: calibrate the antenna array according to the new calibration factor of the antenna array.

[0387] This step is the same as Figure 4 The implementation of step S205 in the corresponding embodiment is similar and will not be repeated here.

[0388] In this embodiment, antenna calibration is first performed using a blind CQI calibration scheme to determine the second calibration factor of the antenna array. After calibrating the antenna array based on the second calibration factor, a CSI-RS is transmitted to the calibration terminal, and the antenna array is calibrated based on PMI feedback. This second calibration yields a new calibration factor for the antenna array, further improving antenna calibration accuracy and downlink transmission performance.

[0389] The technical solution provided in the embodiment of the present application can be applicable to a variety of systems, especially 5G systems. For example, the applicable system can be a global system of mobile communication (GSM) system, a code division multiple access (CDMA) system, a wideband code division multiple access (WCDMA) general packet radio service (GPRS) system, a long term evolution (LTE) system, a LTE frequency division duplex (FDD) system, a LTE time division duplex (TDD) system, an advanced long term evolution (LTE-A) system, a universal mobile telecommunication system (UMTS), a world-wide interoperability for microwave access (WiMAX) system, a 5G new air interface (NR) system, etc. These various systems include terminal equipment and network equipment. The system may also include a core network part, such as an evolved packet system (EPS), a 5G system (5GS), etc.

[0390] The terminal device involved in the embodiments of the present application may be a device that provides voice and / or data connectivity to a user, a handheld device with wireless connection function, or other processing devices connected to a wireless modem. In different systems, the name of the terminal device may also be different. For example, in a 5G system, the terminal device may be called a user equipment (UE). A wireless terminal device can communicate with one or more core networks (CN) via a radio access network (RAN). The wireless terminal device can be a mobile terminal device, such as a mobile phone (or "cellular" phone) and a computer with a mobile terminal device. For example, it can be a portable, pocket-sized, handheld, computer-built-in or vehicle-mounted mobile device that exchanges language and / or data with a radio access network. For example, personal communication service (PCS) phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDAs), and other devices. The wireless terminal device may also be referred to as a system, a subscriber unit, a subscriber station, a mobile station, a mobile station, a remote station, an access point, a remote terminal device, an access terminal device, a user terminal device, a user agent, or a user device, but is not limited in the embodiments of the present application.

[0391] The network device involved in the embodiments of the present application may be a base station, which may include multiple cells providing services to terminals. Depending on the specific application scenario, the base station may also be called an access point, or may be a device in an access network that communicates with a wireless terminal device through one or more sectors on an air interface, or may be named otherwise. The network device may be used to interchange received air frames with Internet Protocol (IP) packets, acting as a router between the wireless terminal device and the rest of the access network, wherein the rest of the access network may include an Internet Protocol (IP) communication network. The network device may also coordinate attribute management of the air interface. For example, the network device involved in the embodiments of the present application may be a network device (Base Transceiver Station, BTS) in the Global System for Mobile communications (GSM) or Code Division Multiple Access (CDMA), or a network device (NodeB) in Wide-band Code Division Multiple Access (WCDMA), or an evolutionary network device (eNB or e-NodeB) in the Long Term Evolution (LTE) system, a 5G base station (gNB) in the 5G network architecture (next generation system), or a home evolved Node B (HeNB), a relay node, a home base station (femto), a pico base station (pico), etc., and is not limited in the embodiments of the present application. In some network structures, the network device may include a centralized unit (CU) node and a distributed unit (DU) node, and the centralized unit and the distributed unit may also be geographically separated.

[0392] Network devices and terminal devices can each use one or more antennas for Multiple Input Multiple Output (MIMO) transmission. MIMO transmission can be either Single User MIMO (SU-MIMO) or Multi User MIMO (MU-MIMO). Depending on the configuration and number of antenna combinations, MIMO transmission can be 2D-MIMO, 3D-MIMO, FD-MIMO, or Massive-MIMO. It can also use diversity transmission, precoding, or beamforming.

[0393] Figure 8 This is a schematic diagram of the structure of an antenna calibration device provided in one embodiment of the present application. Figure 8 As shown, the antenna calibration apparatus 80 includes a transceiver 800 , a processor 810 and a memory 820 .

[0394] Specifically, the transceiver 800 is configured to receive and send data under the control of the processor 810 .

[0395] Among them, Figure 8 In the embodiment, the bus architecture may include any number of interconnected buses and bridges, specifically linking together various circuits of one or more processors represented by processor 810 and memory represented by memory 820. The bus architecture may also link together various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are all well known in the art and, therefore, will not be described further herein. The bus interface provides an interface. The transceiver 800 may be a plurality of components, i.e., a transmitter and a receiver, providing a unit for communicating with various other devices on a transmission medium, such as a wireless channel, a wired channel, an optical cable, and the like. The processor 810 is responsible for managing the bus architecture and general processing, and the memory 820 may store data used by the processor 810 when performing operations.

[0396] The processor 810 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or a complex programmable logic device (CPLD). The processor may also adopt a multi-core architecture.

[0397] The memory 820 is used to store computer programs.

[0398] The processor 810 is configured to read the computer program in the memory 820 and perform the following operations:

[0399] A downlink channel state information reference signal is transmitted to a calibration terminal through an antenna array; a new calibration factor of the antenna array is determined based on the channel state information fed back by the calibration terminal; and the antenna array is calibrated based on the new calibration factor.

[0400] Optionally, the channel state information includes a PMI, which includes information about phase differences between antennas in the same polarization direction. Determining a new calibration factor of the antenna array based on the channel state information fed back by the calibration terminal includes:

[0401] A first calibration factor of the antenna array is determined according to the PMI fed back by the calibration terminal.

[0402] Optionally, before transmitting the downlink channel state information reference signal to the calibration terminal through the antenna array, the method further includes:

[0403] When the first calibration trigger condition is met, determining an antenna group corresponding to the antenna array according to the number of antennas included in the antenna array, where each antenna group includes two polarized antenna pairs;

[0404] A calibration terminal corresponding to the antenna group is determined, and a 2-port channel state information reference signal for calibration is configured for the calibration terminal corresponding to the antenna group.

[0405] Optionally, after determining the first calibration factor of the antenna array according to the PMI fed back by the calibration terminal, the method further includes:

[0406] determining a plurality of different sets of candidate calibration factors for the antenna array based on the first calibration factor for the antenna array;

[0407] Determining a plurality of consecutive feedback cycles based on a plurality of different sets of candidate calibration factors for the antenna array, wherein the feedback cycles correspond one to one to the candidate calibration factors;

[0408] In each feedback cycle, the antenna array is calibrated using the candidate calibration factor corresponding to the feedback cycle, and a downlink channel state information reference signal is transmitted to multiple calibration terminals through the calibrated antenna array;

[0409] A second calibration factor of the antenna array is determined according to the CQIs fed back by the multiple calibration terminals.

[0410] Optionally, the channel state information includes a CQI, and determining a new calibration factor of the antenna array according to the channel state information fed back by the calibration terminal includes:

[0411] A third calibration factor of the antenna array is determined according to the CQIs fed back by the multiple calibration terminals.

[0412] Optionally, transmitting a downlink channel state information reference signal to the calibration terminal through the antenna array includes:

[0413] When the second calibration trigger condition is met, a plurality of consecutive feedback cycles are determined according to a plurality of different candidate calibration factors of the antenna array, wherein the feedback cycles correspond to the candidate calibration factors one by one;

[0414] In each feedback cycle, the antenna array is calibrated using the candidate calibration factor corresponding to the feedback cycle, and then a downlink channel state information reference signal is transmitted to multiple calibration terminals through the calibrated antenna array.

[0415] Optionally, determining a second calibration factor or a third calibration factor for the antenna array according to CQIs fed back by multiple calibration terminals includes:

[0416] Determine a comprehensive CQI in each feedback cycle based on the CQIs fed back by multiple calibration terminals in each feedback cycle;

[0417] The candidate calibration factor corresponding to the feedback period with the maximum comprehensive CQI is used as the second calibration factor or the third calibration factor of the antenna array.

[0418] Optionally, after determining the third calibration factor of the antenna array according to the CQIs fed back by the multiple calibration terminals, the method further includes:

[0419] Determine, based on the number of antennas included in the antenna array, an antenna group corresponding to the antenna array, where each antenna group includes two polarized antenna pairs;

[0420] Determine a calibration terminal corresponding to the antenna group, and configure a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group;

[0421] transmitting, through the antenna group, a downlink channel state information reference signal to a calibration terminal corresponding to the antenna group according to a third calibration factor of the antenna array;

[0422] A fourth calibration factor of the antenna array is determined according to the PMI fed back by the calibration terminal corresponding to the antenna group.

[0423] Optionally, determining an antenna group corresponding to the antenna array according to the number of antennas included in the antenna array includes:

[0424] If the antenna array includes four antennas and the four antennas form two polarized antenna pairs, the four antennas are regarded as an antenna group, and a calibration terminal corresponding to the antenna group is determined. The calibration terminal is a terminal used to calibrate the antenna group.

[0425] Optionally, determining an antenna group corresponding to the antenna array according to the number of antennas included in the antenna array includes:

[0426] If the number of antennas in the antenna array is greater than four, split the antenna array into multiple antenna groups. Each antenna group contains two polarized antenna pairs. Use any polarized antenna pair as a reference antenna pair. Use multiple antenna groups to directly or indirectly associate any polarized antenna with the reference antenna pair.

[0427] If any polarized antenna pair and the reference antenna are in the same antenna group, it is determined that the any polarized antenna pair is directly associated with the reference antenna;

[0428] If any polarized antenna pair and the reference antenna pair are not in the same antenna group, and any polarized antenna and the reference antenna are both directly associated with the first antenna pair, determining that any polarized antenna is indirectly associated with the reference antenna;

[0429] If any polarized antenna is indirectly associated with the second antenna pair, and the second antenna pair is indirectly associated with the reference antenna pair, it is determined that any polarized antenna is indirectly associated with the reference antenna pair.

[0430] Optionally, the antenna array is divided into multiple antenna groups, each antenna group includes two polarized antenna pairs, any polarized antenna pair is used as a reference antenna pair, and any polarized antenna is directly or indirectly associated with the reference antenna pair through the multiple antenna groups, including:

[0431] The antenna array is divided into multiple antenna groups, and any polarized antenna pair is used as a reference antenna pair. Each antenna group includes a reference antenna pair.

[0432] Optionally, determining a calibration terminal corresponding to the antenna group and configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group includes:

[0433] Determine a corresponding calibration terminal for each antenna group, and configure a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to each antenna group, where different calibration terminals correspond to different antenna groups;

[0434] or,

[0435] A calibration terminal shared by multiple antenna groups is determined, and a 2-port channel state information reference signal for calibration is configured for the shared calibration terminal. Each antenna group is calibrated using the shared calibration terminal in different time periods.

[0436] Optionally, determining a first calibration factor or a fourth calibration factor of the antenna array according to a PMI fed back by a calibration terminal corresponding to the antenna group includes:

[0437] Determine an expected calibration phase value corresponding to the antenna group based on a PMI pair fed back by a calibration terminal corresponding to the antenna group, where each PMI pair includes PMIs in two polarization directions;

[0438] Determining a calibration factor for the antenna group based on an expected calibration phase value corresponding to the antenna group;

[0439] A first calibration factor or a fourth calibration factor of the antenna array is determined according to the calibration factor of the antenna group.

[0440] Optionally, determining the calibration phase expected value corresponding to the antenna group according to the PMI pair fed back by the calibration terminal corresponding to the antenna group includes:

[0441] Determine the calibration phase difference coefficient of each PMI pair based on the PMI pairs fed back by each calibration terminal corresponding to the antenna group within a specific time length;

[0442] According to the calibration phase difference coefficient of each PMI pair, the calibration phase expected value corresponding to the antenna group is determined.

[0443] Optionally, determining the calibration phase expected value corresponding to the antenna group according to the calibration phase difference coefficient of each PMI pair includes:

[0444] Perform time-based Kalman filtering on the calibration phase difference coefficient of each PMI pair to determine the calibration phase expected value;

[0445] or,

[0446] According to the signal-to-noise ratio corresponding to each terminal, the calibration phase difference coefficient of the PMI pair fed back by each terminal is weighted and averaged to determine the expected value of the calibration phase;

[0447] or,

[0448] The calibrated phase difference coefficient of any PMI pair is one of the preset phase difference coefficients. Based on the calibrated phase difference coefficient of each PMI pair, the probability of each preset phase difference coefficient occurring within a specific time length is determined, and the preset phase difference coefficients are weighted and summed according to the probability of each preset phase difference coefficient occurring within the specific time length to obtain the expected value of the calibrated phase.

[0449] Optionally, determining a first calibration factor or a fourth calibration factor of the antenna array according to a PMI fed back by a calibration terminal corresponding to the antenna group includes:

[0450] Determine the calibration phase difference for each PMI pair within a specific time period based on the PMI pairs fed back by the calibration terminal corresponding to the antenna group at the current moment, where each PMI pair includes PMIs in two polarization directions;

[0451] Determine the expected phase difference value corresponding to the antenna group at the current moment based on the calibrated phase difference of each PMI pair;

[0452] Determine the calibration error coefficient corresponding to the antenna group at the current moment according to the expected phase difference value corresponding to the antenna group at the current moment;

[0453] If the calibration error coefficient corresponding to the antenna group at the current moment converges, then determining the calibration factor of the antenna group according to the calibration error coefficient corresponding to the antenna group at the current moment;

[0454] A first calibration factor or a fourth calibration factor of the antenna array is determined according to the calibration factor of the antenna group.

[0455] Optionally, determining an expected phase difference value corresponding to the antenna group at a current moment according to the calibrated phase difference of each PMI pair includes:

[0456] Determine, based on the calibration phase difference of each PMI pair, the probability of occurrence of the calibration phase difference of each PMI pair at the current moment;

[0457] According to the probability of occurrence of the calibrated phase difference of each PMI at the current moment, the calibrated phase difference of each PMI pair is weighted and summed to obtain the expected phase difference value corresponding to the antenna group at the current moment.

[0458] Optionally, if the calibration error coefficient corresponding to the antenna group at the current moment converges, before determining the calibration factor of the antenna group according to the calibration error coefficient corresponding to the antenna group at the current moment, the method further includes:

[0459] If the difference between the calibration error coefficient corresponding to the antenna group at the current moment and the calibration error coefficient corresponding to the antenna group at the previous moment is within a preset range, it is determined that the calibration error coefficient corresponding to the antenna group at the current moment converges.

[0460] Optionally, determining a calibration error coefficient corresponding to the antenna group at the current moment based on an expected phase difference value corresponding to the antenna group at the current moment further includes:

[0461] Smoothing the expected phase difference value corresponding to the antenna group at the current moment and the expected phase difference value corresponding to the antenna group at the previous moment to obtain a smoothed expected phase difference value;

[0462] The calibration error coefficient corresponding to the antenna group at the current moment is determined according to the smoothed expected phase difference value.

[0463] Optionally, configuring a calibration terminal corresponding to the antenna group with a 2-port channel state information reference signal for calibration includes:

[0464] Two sets of 2-port channel state information reference signals are configured for the calibration terminal corresponding to the antenna group, where each set of channel state information reference signals is mapped to an antenna in one polarization direction, and two different sets of channel state information reference signals are mapped to antennas in different polarization directions.

[0465] Optionally, configuring a calibration terminal corresponding to the antenna group with a 2-port channel state information reference signal for calibration includes:

[0466] A set of 2-port channel state information reference signals is configured for the calibration terminal corresponding to the antenna group. Using time division multiplexing, a set of 2-port channel state information reference signals is mapped to antennas with different polarization directions in different time periods.

[0467] Optionally, determining a new calibration factor of the antenna array according to the channel state information fed back by the calibration terminal includes:

[0468] Determining a new calibration factor of the antenna array over the wideband based on the channel state information fed back by the calibration terminal based on the wideband;

[0469] or,

[0470] A new calibration factor of the antenna array on each subband is determined according to the channel state information fed back by the calibration terminal based on each subband.

[0471] Optionally, after determining a new calibration factor of the antenna array on each subband according to the channel state information fed back by the calibration terminal based on each subband, the method further includes:

[0472] The new calibration factor of the antenna array in each sub-band is smoothed.

[0473] Optionally, calibrating the antenna array according to the new calibration factor includes:

[0474] Smoothing the calibration factor currently used by the array antenna and the new calibration factor to obtain a revised calibration factor;

[0475] The antennas in the antenna array are calibrated using the corrected calibration factors.

[0476] It should be noted here that the above-mentioned device provided in this application can implement all the method steps implemented in the above-mentioned method embodiment and can achieve the same technical effects. The parts and beneficial effects of this embodiment that are the same as those in the method embodiment will not be described in detail here.

[0477] Figure 9 This is a schematic diagram of the structure of an antenna calibration device provided in one embodiment of the present application. The antenna calibration device provided in this embodiment can perform an antenna calibration method embodiment. Figure 9 As shown, the antenna calibration device 90 includes: a transceiver unit 901, an antenna calibration unit 902 and a calibration execution unit 903.

[0478] Specifically, the transceiver unit 901 is configured to transmit a downlink channel state information reference signal to the calibration terminal through an antenna array.

[0479] The antenna calibration unit 902 is configured to determine a new calibration factor of the antenna array according to the channel state information fed back by the calibration terminal.

[0480] The calibration execution unit 903 is configured to calibrate the antenna array according to the new calibration factor.

[0481] Optionally, the channel state information includes a PMI, which includes information about phase differences between antennas in the same polarization direction. Determining a new calibration factor of the antenna array based on the channel state information fed back by the calibration terminal includes:

[0482] A first calibration factor of the antenna array is determined according to the PMI fed back by the calibration terminal.

[0483] Optionally, before transmitting the downlink channel state information reference signal to the calibration terminal through the antenna array, the method further includes:

[0484] When the first calibration trigger condition is met, determining an antenna group corresponding to the antenna array according to the number of antennas included in the antenna array, where each antenna group includes two polarized antenna pairs;

[0485] A calibration terminal corresponding to the antenna group is determined, and a 2-port channel state information reference signal for calibration is configured for the calibration terminal corresponding to the antenna group.

[0486] Optionally, after determining the first calibration factor of the antenna array according to the PMI fed back by the calibration terminal, the method further includes:

[0487] determining a plurality of different sets of candidate calibration factors for the antenna array based on the first calibration factor for the antenna array;

[0488] Determining a plurality of consecutive feedback cycles based on a plurality of different sets of candidate calibration factors for the antenna array, wherein the feedback cycles correspond one to one to the candidate calibration factors;

[0489] In each feedback cycle, the antenna array is calibrated using the candidate calibration factor corresponding to the feedback cycle, and a downlink channel state information reference signal is transmitted to multiple calibration terminals through the calibrated antenna array;

[0490] A second calibration factor of the antenna array is determined according to the CQIs fed back by the multiple calibration terminals.

[0491] Optionally, the channel state information includes a CQI, and determining a new calibration factor of the antenna array according to the channel state information fed back by the calibration terminal includes:

[0492] A third calibration factor of the antenna array is determined according to the CQIs fed back by the multiple calibration terminals.

[0493] Optionally, transmitting a downlink channel state information reference signal to the calibration terminal through the antenna array includes:

[0494] When the second calibration trigger condition is met, a plurality of consecutive feedback cycles are determined according to a plurality of different candidate calibration factors of the antenna array, wherein the feedback cycles correspond to the candidate calibration factors one by one;

[0495] In each feedback cycle, the antenna array is calibrated using the candidate calibration factor corresponding to the feedback cycle, and then a downlink channel state information reference signal is transmitted to multiple calibration terminals through the calibrated antenna array.

[0496] Optionally, determining a second calibration factor or a third calibration factor for the antenna array according to CQIs fed back by multiple calibration terminals includes:

[0497] Determine a comprehensive CQI in each feedback cycle based on the CQIs fed back by multiple calibration terminals in each feedback cycle;

[0498] The candidate calibration factor corresponding to the feedback period with the maximum comprehensive CQI is used as the second calibration factor or the third calibration factor of the antenna array.

[0499] Optionally, after determining the third calibration factor of the antenna array according to the CQIs fed back by the multiple calibration terminals, the method further includes:

[0500] Determine, based on the number of antennas included in the antenna array, an antenna group corresponding to the antenna array, where each antenna group includes two polarized antenna pairs;

[0501] Determine a calibration terminal corresponding to the antenna group, and configure a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group;

[0502] transmitting, through the antenna group, a downlink channel state information reference signal to a calibration terminal corresponding to the antenna group according to a third calibration factor of the antenna array;

[0503] A fourth calibration factor of the antenna array is determined according to the PMI fed back by the calibration terminal corresponding to the antenna group.

[0504] Optionally, determining an antenna group corresponding to the antenna array according to the number of antennas included in the antenna array includes:

[0505] If the antenna array includes four antennas and the four antennas form two polarized antenna pairs, the four antennas are regarded as an antenna group, and a calibration terminal corresponding to the antenna group is determined. The calibration terminal is a terminal used to calibrate the antenna group.

[0506] Optionally, determining an antenna group corresponding to the antenna array according to the number of antennas included in the antenna array includes:

[0507] If the number of antennas in the antenna array is greater than four, split the antenna array into multiple antenna groups. Each antenna group contains two polarized antenna pairs. Use any polarized antenna pair as a reference antenna pair. Use multiple antenna groups to directly or indirectly associate any polarized antenna with the reference antenna pair.

[0508] If any polarized antenna pair and the reference antenna are in the same antenna group, it is determined that the any polarized antenna pair is directly associated with the reference antenna;

[0509] If any polarized antenna pair and the reference antenna pair are not in the same antenna group, and any polarized antenna and the reference antenna are both directly associated with the first antenna pair, determining that any polarized antenna is indirectly associated with the reference antenna;

[0510] If any polarized antenna is indirectly associated with the second antenna pair, and the second antenna pair is indirectly associated with the reference antenna pair, it is determined that any polarized antenna is indirectly associated with the reference antenna pair.

[0511] Optionally, the antenna array is divided into multiple antenna groups, each antenna group includes two polarized antenna pairs, any polarized antenna pair is used as a reference antenna pair, and any polarized antenna is directly or indirectly associated with the reference antenna pair through the multiple antenna groups, including:

[0512] The antenna array is divided into multiple antenna groups, and any polarized antenna pair is used as a reference antenna pair. Each antenna group includes a reference antenna pair.

[0513] Optionally, determining a calibration terminal corresponding to the antenna group and configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group includes:

[0514] Determine a corresponding calibration terminal for each antenna group, and configure a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to each antenna group, where different calibration terminals correspond to different antenna groups;

[0515] or,

[0516] A calibration terminal shared by multiple antenna groups is determined, and a 2-port channel state information reference signal for calibration is configured for the shared calibration terminal. Each antenna group is calibrated using the shared calibration terminal in different time periods.

[0517] Optionally, determining a first calibration factor or a fourth calibration factor of the antenna array according to a PMI fed back by a calibration terminal corresponding to the antenna group includes:

[0518] Determine an expected calibration phase value corresponding to the antenna group based on a PMI pair fed back by a calibration terminal corresponding to the antenna group, where each PMI pair includes PMIs in two polarization directions;

[0519] Determining a calibration factor for the antenna group based on an expected calibration phase value corresponding to the antenna group;

[0520] A first calibration factor or a fourth calibration factor of the antenna array is determined according to the calibration factor of the antenna group.

[0521] Optionally, determining the calibration phase expected value corresponding to the antenna group according to the PMI pair fed back by the calibration terminal corresponding to the antenna group includes:

[0522] Determine the calibration phase difference coefficient of each PMI pair based on the PMI pairs fed back by each calibration terminal corresponding to the antenna group within a specific time length;

[0523] According to the calibration phase difference coefficient of each PMI pair, the calibration phase expected value corresponding to the antenna group is determined.

[0524] Optionally, determining the calibration phase expected value corresponding to the antenna group according to the calibration phase difference coefficient of each PMI pair includes:

[0525] Perform time-based Kalman filtering on the calibration phase difference coefficient of each PMI pair to determine the calibration phase expected value;

[0526] or,

[0527] According to the signal-to-noise ratio corresponding to each terminal, the calibration phase difference coefficient of the PMI pair fed back by each terminal is weighted and averaged to determine the expected value of the calibration phase;

[0528] or,

[0529] The calibrated phase difference coefficient of any PMI pair is one of the preset phase difference coefficients. Based on the calibrated phase difference coefficient of each PMI pair, the probability of each preset phase difference coefficient occurring within a specific time length is determined, and the preset phase difference coefficients are weighted and summed according to the probability of each preset phase difference coefficient occurring within the specific time length to obtain the expected value of the calibrated phase.

[0530] Optionally, determining a first calibration factor or a fourth calibration factor of the antenna array according to a PMI fed back by a calibration terminal corresponding to the antenna group includes:

[0531] Determine the calibration phase difference for each PMI pair within a specific time period based on the PMI pairs fed back by the calibration terminal corresponding to the antenna group at the current moment, where each PMI pair includes PMIs in two polarization directions;

[0532] Determine the expected phase difference value corresponding to the antenna group at the current moment based on the calibrated phase difference of each PMI pair;

[0533] Determine the calibration error coefficient corresponding to the antenna group at the current moment according to the expected phase difference value corresponding to the antenna group at the current moment;

[0534] If the calibration error coefficient corresponding to the antenna group at the current moment converges, then determining the calibration factor of the antenna group according to the calibration error coefficient corresponding to the antenna group at the current moment;

[0535] A first calibration factor or a fourth calibration factor of the antenna array is determined according to the calibration factor of the antenna group.

[0536] Optionally, determining an expected phase difference value corresponding to the antenna group at a current moment according to the calibrated phase difference of each PMI pair includes:

[0537] Determine, based on the calibration phase difference of each PMI pair, the probability of occurrence of the calibration phase difference of each PMI pair at the current moment;

[0538] According to the probability of occurrence of the calibrated phase difference of each PMI at the current moment, the calibrated phase difference of each PMI pair is weighted and summed to obtain the expected phase difference value corresponding to the antenna group at the current moment.

[0539] Optionally, if the calibration error coefficient corresponding to the antenna group at the current moment converges, before determining the calibration factor of the antenna group according to the calibration error coefficient corresponding to the antenna group at the current moment, the method further includes:

[0540] If the difference between the calibration error coefficient corresponding to the antenna group at the current moment and the calibration error coefficient corresponding to the antenna group at the previous moment is within a preset range, it is determined that the calibration error coefficient corresponding to the antenna group at the current moment converges.

[0541] Optionally, determining a calibration error coefficient corresponding to the antenna group at the current moment based on an expected phase difference value corresponding to the antenna group at the current moment further includes:

[0542] Smoothing the expected phase difference value corresponding to the antenna group at the current moment and the expected phase difference value corresponding to the antenna group at the previous moment to obtain a smoothed expected phase difference value;

[0543] The calibration error coefficient corresponding to the antenna group at the current moment is determined according to the smoothed expected phase difference value.

[0544] Optionally, configuring a calibration terminal corresponding to the antenna group with a 2-port channel state information reference signal for calibration includes:

[0545] Two sets of 2-port channel state information reference signals are configured for the calibration terminal corresponding to the antenna group, where each set of channel state information reference signals is mapped to an antenna in one polarization direction, and two different sets of channel state information reference signals are mapped to antennas in different polarization directions.

[0546] Optionally, configuring a calibration terminal corresponding to the antenna group with a 2-port channel state information reference signal for calibration includes:

[0547] A set of 2-port channel state information reference signals is configured for the calibration terminal corresponding to the antenna group. Using time division multiplexing, a set of 2-port channel state information reference signals is mapped to antennas with different polarization directions in different time periods.

[0548] Optionally, determining a new calibration factor of the antenna array according to the channel state information fed back by the calibration terminal includes:

[0549] Determining a new calibration factor of the antenna array over the wideband based on the channel state information fed back by the calibration terminal based on the wideband;

[0550] or,

[0551] A new calibration factor of the antenna array on each subband is determined according to the channel state information fed back by the calibration terminal based on each subband.

[0552] Optionally, after determining a new calibration factor of the antenna array on each subband according to the channel state information fed back by the calibration terminal based on each subband, the method further includes:

[0553] The new calibration factor of the antenna array in each sub-band is smoothed.

[0554] Optionally, calibrating the antenna array according to the new calibration factor includes:

[0555] Smoothing the calibration factor currently used by the array antenna and the new calibration factor to obtain a revised calibration factor;

[0556] The antennas in the antenna array are calibrated using the corrected calibration factors.

[0557] It should be noted that the division of units in the embodiments of the present application is schematic and is merely a logical functional division. In actual implementation, other division methods may be used. Furthermore, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0558] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a processor-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) or a processor to execute all or part of the steps of the various embodiments of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0559] It should be noted here that the above-mentioned device provided in this application can implement all the method steps implemented in the above-mentioned method embodiment and can achieve the same technical effects. The parts and beneficial effects of this embodiment that are the same as those in the method embodiment will not be described in detail here.

[0560] The present application also provides a processor-readable storage medium, which stores a computer program. The computer program is used to enable a processor to execute the method provided by any of the above method embodiments.

[0561] The processor-readable storage medium can be any available medium or data storage device that can be accessed by the processor, including but not limited to magnetic storage (such as floppy disks, hard disks, magnetic tapes, magneto-optical disks (MO)), optical storage (such as CDs, DVDs, BDs, HVDs, etc.), and semiconductor storage (such as ROMs, EPROMs, EEPROMs, non-volatile memories (NAND FLASH), solid-state drives (SSDs)), etc.

[0562] The present application also provides a computer program product, which includes: a computer program, the computer program is stored in a readable storage medium, at least one processor can read the computer program from the readable storage medium, and at least one processor executes the computer program to implement the solution provided by any of the above method embodiments.

[0563] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage and optical storage, etc.) that contain computer-usable program code.

[0564] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer-executable instructions. These computer-executable instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0565] These processor-executable instructions may also be stored in a processor-readable memory that can direct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the processor-readable memory produce an article of manufacture comprising an instruction device that implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0566] These processor-executable instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are performed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for executing on the computer or other programmable device to implement the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0567] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.

Claims

1. A method for antenna calibration, characterized in that: The method includes: Transmitting a downlink channel state information reference signal to the calibration terminal via an antenna array; Determining a new calibration factor for the antenna array according to the channel state information fed back by the calibration terminal; calibrating the antenna array according to the new calibration factor; The channel state information includes PMI, and the PMI includes information about the phase difference of antennas in the same polarization direction. The determining, according to the channel state information fed back by the calibration terminal, a new calibration factor of the antenna array includes: A first calibration factor of the antenna array is determined according to the PMI fed back by the calibration terminal.

2. The method according to claim 1, characterized in that Before transmitting the downlink channel state information reference signal to the calibration terminal through the antenna array, the method further includes: When a first calibration trigger condition is met, determining an antenna group corresponding to the antenna array according to the number of antennas included in the antenna array, wherein each antenna group includes two polarized antenna pairs; A calibration terminal corresponding to the antenna group is determined, and a 2-port channel state information reference signal for calibration is configured for the calibration terminal corresponding to the antenna group.

3. The method according to claim 1, characterized in that After determining the first calibration factor of the antenna array according to the PMI fed back by the calibration terminal, the method further includes: determining a plurality of different sets of candidate calibration factors for the antenna array based on the first calibration factor for the antenna array; determining a plurality of consecutive feedback cycles based on a plurality of different sets of candidate calibration factors for the antenna array, the feedback cycles corresponding one-to-one to the candidate calibration factors; In each feedback cycle, after calibrating the antenna array using the candidate calibration factor corresponding to the feedback cycle, transmitting a downlink channel state information reference signal to multiple calibration terminals through the calibrated antenna array; A second calibration factor for the antenna array is determined according to the CQIs fed back by the multiple calibration terminals.

4. The method according to claim 1, wherein The channel state information includes a CQI, and determining a new calibration factor of the antenna array according to the channel state information fed back by the calibration terminal includes: A third calibration factor of the antenna array is determined according to the CQIs fed back by the multiple calibration terminals.

5. The method according to claim 4, characterized in that The transmitting a downlink channel state information reference signal to the calibration terminal through the antenna array includes: When a second calibration trigger condition is met, determining a plurality of consecutive feedback cycles based on a plurality of different candidate calibration factors for the antenna array, the feedback cycles corresponding one-to-one to the candidate calibration factors; In each feedback cycle, the antenna array is calibrated using the candidate calibration factor corresponding to the feedback cycle, and a downlink channel state information reference signal is transmitted to multiple calibration terminals through the calibrated antenna array.

6. The method according to claim 3 or 5, characterized in that Determining, according to the CQIs fed back by the multiple calibration terminals, a second calibration factor or a third calibration factor for the antenna array, including: Determining a comprehensive CQI in each feedback cycle according to the CQIs fed back by the multiple calibration terminals in each feedback cycle; The candidate calibration factor corresponding to the feedback period with the maximum comprehensive CQI is used as the second calibration factor or the third calibration factor of the antenna array.

7. The method according to claim 4, characterized in that After determining the third calibration factor of the antenna array according to the CQIs fed back by the multiple calibration terminals, the method further includes: Determining, according to the number of antennas included in the antenna array, an antenna group corresponding to the antenna array, wherein each antenna group includes two polarized antenna pairs; Determining a calibration terminal corresponding to the antenna group, and configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group; transmitting, through the antenna group, a downlink channel state information reference signal to a calibration terminal corresponding to the antenna group according to a third calibration factor of the antenna array; A fourth calibration factor of the antenna array is determined according to the PMI fed back by the calibration terminal corresponding to the antenna group.

8. The method according to claim 2 or 7, characterized in that The determining, according to the number of antennas included in the antenna array, an antenna group corresponding to the antenna array includes: If the antenna array includes four antennas and the four antennas form two polarized antenna pairs, the four antennas are regarded as an antenna group, and a calibration terminal corresponding to the antenna group is determined. The calibration terminal is a terminal used to calibrate the antenna group.

9. The method according to claim 2 or 7, characterized in that The determining, according to the number of antennas included in the antenna array, an antenna group corresponding to the antenna array includes: If the number of antennas in the antenna array is greater than four, splitting the antenna array into multiple antenna groups, each antenna group including two polarized antenna pairs, using any polarized antenna pair as a reference antenna pair, and directly or indirectly associating any polarized antenna with the reference antenna pair through the multiple antenna groups; If any polarized antenna pair and the reference antenna pair are in the same antenna group, determining that the any polarized antenna pair is directly associated with the reference antenna pair; If any polarized antenna pair and the reference antenna pair are not in the same antenna group, and both the any polarized antenna and the reference antenna pair are directly associated with the first antenna pair, determining that the any polarized antenna is indirectly associated with the reference antenna pair; If any one of the polarized antennas is indirectly associated with the second antenna pair, and the second antenna pair is indirectly associated with the reference antenna pair, it is determined that any one of the polarized antennas is indirectly associated with the reference antenna pair.

10. The method according to claim 9, characterized in that The step of dividing the antenna array into a plurality of antenna groups, each of the antenna groups including two polarized antenna pairs, using any polarized antenna pair as a reference antenna pair, and directly or indirectly associating any polarized antenna with the reference antenna pair through the plurality of antenna groups includes: The antenna array is divided into multiple antenna groups, and any polarized antenna pair is used as a reference antenna pair. Each of the antenna groups includes the reference antenna pair.

11. The method according to claim 9, characterized in that The determining the calibration terminal corresponding to the antenna group and configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group includes: Determining a corresponding calibration terminal for each antenna group, and configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to each antenna group, wherein different antenna groups correspond to different calibration terminals; or, A calibration terminal shared by the multiple antenna groups is determined, and a 2-port channel state information reference signal for calibration is configured for the shared calibration terminal. Each of the antenna groups is calibrated in different time periods using the shared calibration terminal.

12. The method according to claim 2 or 7, characterized in that Determining a first calibration factor or a fourth calibration factor of the antenna array according to the PMI fed back by the calibration terminal corresponding to the antenna group includes: Determining an expected calibration phase value corresponding to the antenna group according to a PMI pair fed back by a calibration terminal corresponding to the antenna group, wherein each PMI pair includes PMIs in two polarization directions; Determining a calibration factor for the antenna group according to an expected calibration phase value corresponding to the antenna group; A first calibration factor or a fourth calibration factor of the antenna array is determined according to the calibration factor of the antenna group.

13. The method according to claim 12, characterized in that The determining, based on the PMI pair fed back by the calibration terminal corresponding to the antenna group, the expected calibration phase value corresponding to the antenna group, includes: Determining a calibration phase difference coefficient for each PMI pair based on the PMI pairs fed back by each calibration terminal corresponding to the antenna group within a specific time period; According to the calibration phase difference coefficient of each PMI pair, an expected calibration phase value corresponding to the antenna group is determined.

14. The method according to claim 13, characterized in that The determining, according to the calibration phase difference coefficient of each of the PMI pairs, an expected calibration phase value corresponding to the antenna group includes: Performing a time-based Kalman filter process on the calibration phase difference coefficient of each of the PMI pairs to determine the calibration phase expected value; or, According to the signal-to-noise ratio corresponding to each terminal, weighted averaging the calibration phase difference coefficients of the PMI pairs fed back by each terminal to determine the calibration phase expected value; or, The calibrated phase difference coefficient of any of the PMI pairs is one of the preset phase difference coefficients. According to the calibrated phase difference coefficient of each of the PMI pairs, the probability of each of the preset phase difference coefficients occurring within the specific time length is determined, and the preset phase difference coefficients are weighted and summed according to the probability of each of the preset phase difference coefficients occurring within the specific time length to obtain the expected value of the calibrated phase.

15. The method according to claim 2 or 7, characterized in that Determining a first calibration factor or a fourth calibration factor of the antenna array according to the PMI fed back by the calibration terminal corresponding to the antenna group includes: Determine, within a specific time period, a calibration phase difference for each PMI pair based on the PMI pairs fed back by the calibration terminal corresponding to the antenna group at the current moment, wherein each PMI pair includes PMIs in two polarization directions; Determining an expected phase difference value corresponding to the antenna group at a current moment according to the calibrated phase difference of each PMI pair; Determining a calibration error coefficient corresponding to the antenna group at the current moment according to an expected phase difference value corresponding to the antenna group at the current moment; If the calibration error coefficient corresponding to the antenna group at the current moment converges, determining the calibration factor of the antenna group according to the calibration error coefficient corresponding to the antenna group at the current moment; A first calibration factor or a fourth calibration factor of the antenna array is determined according to the calibration factor of the antenna group.

16. The method according to claim 15, characterized in that The determining, based on the calibrated phase difference of each of the PMI pairs, an expected phase difference value corresponding to the antenna group at a current moment, includes: Determining, based on the calibration phase difference of each of the PMI pairs, a probability of occurrence of the calibration phase difference of each of the PMI pairs at a current moment; According to the probability of occurrence of the calibrated phase difference of each PMI at the current moment, the calibrated phase difference of each PMI pair is weighted and summed to obtain the expected phase difference value corresponding to the antenna group at the current moment.

17. The method according to claim 15, characterized in that If the calibration error coefficient corresponding to the antenna group at the current moment converges, before determining the calibration factor of the antenna group according to the calibration error coefficient corresponding to the antenna group at the current moment, the method further includes: If the difference between the calibration error coefficient corresponding to the antenna group at the current moment and the calibration error coefficient corresponding to the antenna group at the previous moment is within a preset range, it is determined that the calibration error coefficient corresponding to the antenna group at the current moment converges.

18. The method according to claim 15, characterized in that The step of determining the calibration error coefficient corresponding to the antenna group at the current moment according to the expected phase difference value corresponding to the antenna group at the current moment further includes: Smoothing the expected phase difference value corresponding to the antenna group at the current moment and the expected phase difference value corresponding to the antenna group at the previous moment to obtain a smoothed expected phase difference value; A calibration error coefficient corresponding to the antenna group at a current moment is determined according to the smoothed expected phase difference value.

19. The method according to claim 2 or 7, characterized in that The configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group includes: Two sets of 2-port channel state information reference signals are configured for the calibration terminal corresponding to the antenna group, wherein each set of channel state information reference signals is mapped to an antenna in one polarization direction, and two different sets of channel state information reference signals are mapped to antennas in different polarization directions.

20. The method according to claim 2 or 7, characterized in that The configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group includes: A set of 2-port channel state information reference signals is configured for the calibration terminal corresponding to the antenna group. The set of 2-port channel state information reference signals is mapped to antennas with different polarization directions in different time periods using a time division multiplexing method.

21. The method according to claim 1, wherein The determining, according to the channel state information fed back by the calibration terminal, a new calibration factor of the antenna array includes: determining a new calibration factor of the antenna array on the broadband according to the channel state information fed back by the calibration terminal based on the broadband; or, A new calibration factor of the antenna array on each subband is determined according to the channel state information fed back by the calibration terminal based on each subband.

22. The method according to claim 18, wherein After determining a new calibration factor of the antenna array on each subband according to the channel state information fed back by the calibration terminal based on each subband, the method further includes: A smoothing process is performed on the new calibration factor of the antenna array in each sub-band.

23. The method according to claim 1, wherein The calibrating the antenna array according to the new calibration factor includes: Smoothing the calibration factor currently used by the antenna array and the new calibration factor to obtain a revised calibration factor; The antennas in the antenna array are calibrated using the corrected calibration factors.

24. An antenna calibration device, characterized in that: Including memory, transceiver, processor: Memory for storing computer programs; a transceiver, configured to transmit and receive data under the control of the processor; A processor is configured to read the computer program in the memory and perform the following operations: Transmitting a downlink channel state information reference signal to the calibration terminal via an antenna array; Determining a new calibration factor for the antenna array according to the channel state information fed back by the calibration terminal; calibrating the antenna array according to the new calibration factor; The channel state information includes PMI, and the PMI includes information about the phase difference of antennas in the same polarization direction. The determining, according to the channel state information fed back by the calibration terminal, a new calibration factor of the antenna array includes: A first calibration factor of the antenna array is determined according to the PMI fed back by the calibration terminal.

25. The device according to claim 24, characterized in that Before transmitting the downlink channel state information reference signal to the calibration terminal through the antenna array, the method further includes: When a first calibration trigger condition is met, determining an antenna group corresponding to the antenna array according to the number of antennas included in the antenna array, wherein each antenna group includes two polarized antenna pairs; A calibration terminal corresponding to the antenna group is determined, and a 2-port channel state information reference signal for calibration is configured for the calibration terminal corresponding to the antenna group.

26. The device according to claim 24, characterized in that After determining the first calibration factor of the antenna array according to the PMI fed back by the calibration terminal, the method further includes: determining a plurality of different sets of candidate calibration factors for the antenna array based on the first calibration factor for the antenna array; determining a plurality of consecutive feedback cycles based on a plurality of different sets of candidate calibration factors for the antenna array, the feedback cycles corresponding one-to-one to the candidate calibration factors; In each feedback cycle, after calibrating the antenna array using the candidate calibration factor corresponding to the feedback cycle, transmitting a downlink channel state information reference signal to multiple calibration terminals through the calibrated antenna array; A second calibration factor for the antenna array is determined according to the CQIs fed back by the multiple calibration terminals.

27. The device according to claim 24, characterized in that The channel state information includes a CQI, and determining a new calibration factor of the antenna array according to the channel state information fed back by the calibration terminal includes: A third calibration factor of the antenna array is determined according to the CQIs fed back by the multiple calibration terminals.

28. The device according to claim 27, characterized in that The transmitting a downlink channel state information reference signal to the calibration terminal through the antenna array includes: When a second calibration trigger condition is met, determining a plurality of consecutive feedback cycles based on a plurality of different candidate calibration factors for the antenna array, the feedback cycles corresponding one-to-one to the candidate calibration factors; In each feedback cycle, the antenna array is calibrated using the candidate calibration factor corresponding to the feedback cycle, and a downlink channel state information reference signal is transmitted to multiple calibration terminals through the calibrated antenna array.

29. The device according to claim 26 or 28, characterized in that Determining, according to the CQIs fed back by the multiple calibration terminals, a second calibration factor or a third calibration factor for the antenna array, including: Determining a comprehensive CQI in each feedback cycle according to the CQIs fed back by the multiple calibration terminals in each feedback cycle; The candidate calibration factor corresponding to the feedback period with the maximum comprehensive CQI is used as the second calibration factor or the third calibration factor of the antenna array.

30. The device according to claim 27, characterized in that After determining the third calibration factor of the antenna array according to the CQIs fed back by the multiple calibration terminals, the method further includes: Determining, according to the number of antennas included in the antenna array, an antenna group corresponding to the antenna array, wherein each antenna group includes two polarized antenna pairs; Determining a calibration terminal corresponding to the antenna group, and configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group; transmitting, through the antenna group, a downlink channel state information reference signal to a calibration terminal corresponding to the antenna group according to a third calibration factor of the antenna array; A fourth calibration factor of the antenna array is determined according to the PMI fed back by the calibration terminal corresponding to the antenna group.

31. The device according to claim 25 or 30, characterized in that The determining, according to the number of antennas included in the antenna array, an antenna group corresponding to the antenna array includes: If the antenna array includes four antennas and the four antennas form two polarized antenna pairs, the four antennas are regarded as an antenna group, and a calibration terminal corresponding to the antenna group is determined. The calibration terminal is a terminal used to calibrate the antenna group.

32. The device according to claim 25 or 30, characterized in that The determining, according to the number of antennas included in the antenna array, an antenna group corresponding to the antenna array includes: If the number of antennas in the antenna array is greater than four, splitting the antenna array into multiple antenna groups, each antenna group including two polarized antenna pairs, using any polarized antenna pair as a reference antenna pair, and directly or indirectly associating any polarized antenna with the reference antenna pair through the multiple antenna groups; If any polarized antenna pair and the reference antenna pair are in the same antenna group, determining that the any polarized antenna pair is directly associated with the reference antenna pair; If any polarized antenna pair and the reference antenna pair are not in the same antenna group, and both the any polarized antenna and the reference antenna pair are directly associated with the first antenna pair, determining that the any polarized antenna is indirectly associated with the reference antenna pair; If any one of the polarized antennas is indirectly associated with the second antenna pair, and the second antenna pair is indirectly associated with the reference antenna pair, it is determined that any one of the polarized antennas is indirectly associated with the reference antenna pair.

33. The device according to claim 32, characterized in that The step of splitting the antenna array into a plurality of antenna groups, each of the antenna groups including two polarized antenna pairs, using any polarized antenna pair as a reference antenna pair, and directly or indirectly associating any polarized antenna with the reference antenna pair through the plurality of antenna groups includes: The antenna array is divided into multiple antenna groups, and any polarized antenna pair is used as a reference antenna pair. Each of the antenna groups includes the reference antenna pair.

34. The device according to claim 32, characterized in that The determining the calibration terminal corresponding to the antenna group and configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group includes: Determining a corresponding calibration terminal for each antenna group, and configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to each antenna group, wherein different antenna groups correspond to different calibration terminals; or, A calibration terminal shared by the multiple antenna groups is determined, and a 2-port channel state information reference signal for calibration is configured for the shared calibration terminal. Each of the antenna groups is calibrated in different time periods using the shared calibration terminal.

35. The device according to claim 25 or 30, characterized in that Determining a first calibration factor of the antenna array according to the PMI fed back by the calibration terminal corresponding to the antenna group includes: Determining an expected calibration phase value corresponding to the antenna group according to a PMI pair fed back by a calibration terminal corresponding to the antenna group, wherein each PMI pair includes PMIs in two polarization directions; Determining a calibration factor for the antenna group according to an expected calibration phase value corresponding to the antenna group; A first calibration factor of the antenna array is determined according to the calibration factor of the antenna group.

36. The device according to claim 35, characterized in that The determining, based on the PMI pair fed back by the calibration terminal corresponding to the antenna group, the expected calibration phase value corresponding to the antenna group, includes: Determining a calibration phase difference coefficient for each PMI pair based on the PMI pairs fed back by each calibration terminal corresponding to the antenna group within a specific time period; According to the calibration phase difference coefficient of each PMI pair, an expected calibration phase value corresponding to the antenna group is determined.

37. The device according to claim 36, characterized in that The determining, according to the calibration phase difference coefficient of each of the PMI pairs, an expected calibration phase value corresponding to the antenna group includes: Performing a time-based Kalman filter process on the calibration phase difference coefficient of each of the PMI pairs to determine the calibration phase expected value; or, According to the signal-to-noise ratio corresponding to each terminal, weighted averaging the calibration phase difference coefficients of the PMI pairs fed back by each terminal to determine the calibration phase expected value; or, The calibrated phase difference coefficient of any of the PMI pairs is one of the preset phase difference coefficients. According to the calibrated phase difference coefficient of each of the PMI pairs, the probability of each of the preset phase difference coefficients occurring within the specific time length is determined, and the preset phase difference coefficients are weighted and summed according to the probability of each of the preset phase difference coefficients occurring within the specific time length to obtain the expected value of the calibrated phase.

38. The device according to claim 25 or 30, characterized in that Determining a first calibration factor or a fourth calibration factor of the antenna array according to the PMI fed back by the calibration terminal corresponding to the antenna group includes: Determine, within a specific time period, a calibration phase difference for each PMI pair based on the PMI pairs fed back by the calibration terminal corresponding to the antenna group at the current moment, wherein each PMI pair includes PMIs in two polarization directions; Determining an expected phase difference value corresponding to the antenna group at a current moment according to the calibrated phase difference of each PMI pair; Determining a calibration error coefficient corresponding to the antenna group at the current moment according to an expected phase difference value corresponding to the antenna group at the current moment; If the calibration error coefficient corresponding to the antenna group at the current moment converges, determining the calibration factor of the antenna group according to the calibration error coefficient corresponding to the antenna group at the current moment; A first calibration factor or a fourth calibration factor of the antenna array is determined according to the calibration factor of the antenna group.

39. The device according to claim 38, characterized in that The determining, based on the calibrated phase difference of each of the PMI pairs, an expected phase difference value corresponding to the antenna group at a current moment, includes: Determining, based on the calibration phase difference of each of the PMI pairs, a probability of occurrence of the calibration phase difference of each of the PMI pairs at a current moment; According to the probability of occurrence of the calibrated phase difference of each PMI at the current moment, the calibrated phase difference of each PMI pair is weighted and summed to obtain the expected phase difference value corresponding to the antenna group at the current moment.

40. The device according to claim 38, wherein If the calibration error coefficient corresponding to the antenna group at the current moment converges, before determining the calibration factor of the antenna group according to the calibration error coefficient corresponding to the antenna group at the current moment, the method further includes: If the difference between the calibration error coefficient corresponding to the antenna group at the current moment and the calibration error coefficient corresponding to the antenna group at the previous moment is within a preset range, it is determined that the calibration error coefficient corresponding to the antenna group at the current moment converges.

41. The device according to claim 38, wherein The step of determining the calibration error coefficient corresponding to the antenna group at the current moment according to the expected phase difference value corresponding to the antenna group at the current moment further includes: Smoothing the expected phase difference value corresponding to the antenna group at the current moment and the expected phase difference value corresponding to the antenna group at the previous moment to obtain a smoothed expected phase difference value; A calibration error coefficient corresponding to the antenna group at a current moment is determined according to the smoothed expected phase difference value.

42. The device according to claim 25 or 30, characterized in that The configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group includes: Two sets of 2-port channel state information reference signals are configured for the calibration terminal corresponding to the antenna group, wherein each set of channel state information reference signals is mapped to an antenna in one polarization direction, and two different sets of channel state information reference signals are mapped to antennas in different polarization directions.

43. The device according to claim 25 or 30, characterized in that The configuring a 2-port channel state information reference signal for calibration for the calibration terminal corresponding to the antenna group includes: A set of 2-port channel state information reference signals is configured for the calibration terminal corresponding to the antenna group. The set of 2-port channel state information reference signals is mapped to antennas with different polarization directions in different time periods using a time division multiplexing method.

44. The device according to claim 24, characterized in that The determining, according to the channel state information fed back by the calibration terminal, a new calibration factor of the antenna array includes: determining a new calibration factor of the antenna array on the broadband according to the channel state information fed back by the calibration terminal based on the broadband; or, A new calibration factor of the antenna array on each subband is determined according to the channel state information fed back by the calibration terminal based on each subband.

45. The device according to claim 42, characterized in that After determining a new calibration factor of the antenna array on each subband according to the channel state information fed back by the calibration terminal based on each subband, the method further includes: A smoothing process is performed on the new calibration factor of the antenna array in each sub-band.

46. ​​The device according to claim 24, characterized in that The calibrating the antenna array according to the new calibration factor includes: Smoothing the calibration factor currently used by the antenna array and the new calibration factor to obtain a revised calibration factor; The antennas in the antenna array are calibrated using the corrected calibration factors.

47. An antenna calibration device, characterized in that: include: A transceiver unit, configured to transmit a downlink channel state information reference signal to the calibration terminal via an antenna array; an antenna calibration unit, configured to determine a new calibration factor of the antenna array based on the channel state information fed back by the calibration terminal; a calibration execution unit, configured to calibrate the antenna array according to the new calibration factor; The antenna calibration unit is specifically configured to determine a first calibration factor of the antenna array based on the PMI fed back by the calibration terminal; the channel state information includes the PMI, and the PMI includes information on the phase difference of antennas in the same polarization direction.

48. A processor-readable storage medium, characterized in that The processor-readable storage medium stores a computer program, and the computer program is used to enable the processor to execute the method according to any one of claims 1 to 23.

49. A computer program product, characterized in that The invention comprises a computer program which, when executed by a processor, implements the method according to any one of claims 1 to 23.

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