CN115473589A

CN115473589A - Calibration processing method, device and equipment

Info

Publication number: CN115473589A
Application number: CN202110653379.6A
Authority: CN
Inventors: 石璟; 章勇
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2021-06-11
Filing date: 2021-06-11
Publication date: 2022-12-13

Abstract

The application provides a calibration processing method, a calibration processing device and calibration processing equipment, and relates to the technical field of communication. The method comprises the following steps: the method comprises the steps that network side equipment groups a plurality of RRUs, wherein at least one RRU in each group of RRUs belongs to at least one residual group, and all the grouped RRUs are communicated; the network side equipment sequentially selects each group of RRUs and corresponding target RRUs to mutually transmit a calibration sequence; the network side equipment acquires a channel estimation result during the transmission of the calibration sequence; the network side equipment obtains a target calibration parameter according to the channel estimation result; and the network side equipment performs signal transmission compensation according to the antenna corresponding to the target calibration parameter. The scheme of the application solves the problem that the prior calibration mode consumes too many air interface resources, which causes the reduction of the system throughput.

Description

Calibration processing method, device and equipment

Technical Field

The present application relates to the field of communications technologies, and in particular, to a calibration processing method, apparatus, and device.

Background

Time Division multiplexing (TDD) room scenes, and Radio Remote Units (RRUs) do not have a calibration network designed to reduce cost, and cannot perform hardware calibration.

However, in the existing calibration mode, calibration is performed through signal transmission between a terminal and a base station, a downlink channel needs to be quantized and then fed back through an air interface, which consumes a large amount of air interface resources and causes a decrease in system throughput.

Disclosure of Invention

The application aims to provide a calibration processing method, a calibration processing device and calibration processing equipment, which are used for solving the problem that the throughput of a system is reduced due to excessive air interface resource consumption in the conventional calibration mode.

In order to achieve the above object, an embodiment of the present application provides a calibration processing method, including:

the method comprises the steps that a network side device groups a plurality of RRUs, wherein at least one RRU in each group of RRUs belongs to at least one residual group, and all grouped RRUs are communicated;

the network side equipment sequentially selects each group of RRUs and corresponding target RRUs to mutually transmit a calibration sequence;

the network side equipment acquires a channel estimation result during the transmission of the calibration sequence;

the network side equipment obtains a target calibration parameter according to the channel estimation result;

and the network side equipment performs signal transmission compensation according to the antenna corresponding to the target calibration parameter.

Optionally, the selecting, by the network side device, each group of RRUs and a corresponding target RRU in sequence to transmit a calibration sequence, where the calibration sequence includes:

the method comprises the steps that under the condition that a second group of RRUs are selected by the network side equipment to send calibration sequences, at least one RRU is selected from groups except the second group of RRUs to serve as a target RRU, and the target RRU receives the calibration sequences sent by the second group of RRUs;

the network side equipment receives the calibration sequence sent by the target RRU through the s-th group RRU under the condition that the target RRU sends the calibration sequence;

wherein s is an integer greater than or equal to 1.

Optionally, the obtaining, by the network side device, a channel estimation result during transmission of the calibration sequence includes:

when the calibration sequences are mutually transmitted by the s group of RRUs and the target RRU, the network side equipment performs channel estimation on the first channel to obtain a first channel estimation result, and performs channel estimation on the second channel to obtain a second channel estimation result;

wherein the first channel is a channel for the s-th group of RRUs to send a calibration sequence to the target RRU, and the second channel is a channel for the target RRU to send a calibration sequence to the s-th group of RRUs.

Optionally, the obtaining, by the network device, the target calibration parameter according to the channel estimation result includes:

the network side equipment obtains a first calibration parameter of each frequency point of each group of RRUs on the bandwidth according to the channel estimation result corresponding to each group of RRUs;

and the network side equipment respectively combines the first calibration parameters of each group of RRUs at different frequency points to obtain the target calibration parameters of each frequency point on the bandwidth.

Optionally, the obtaining, by the network side device, the first calibration parameter of each frequency point on the bandwidth of each group of RRUs according to the channel estimation result corresponding to each group of RRUs includes:

when the network side equipment transmits calibration sequences to the s-th group of RRUs and the target RRU, calculating all second calibration parameters of the s-th group of RRUs at the current frequency point according to a first channel estimation result and a second channel estimation result of the current frequency point;

and the network side equipment calculates the first calibration parameters of the s group of RRUs at the current frequency point according to all the second calibration parameters.

Optionally, the calculating all second calibration parameters of the s group of RRUs at the current frequency point according to the first channel estimation result and the second channel estimation result of the current frequency point includes:

the network side equipment acquires a first channel estimationResult counting

Ith row and second channel estimation results of

After the ith column, a current second calibration parameter is obtained by dot division and normalization processing based on the first antenna

Wherein i is an integer greater than or equal to 1.

Optionally, the calculating, by the network side device, the first calibration parameter of the s-th group of RRUs at the current frequency point according to all the second calibration parameters includes:

and the network side equipment performs weighted summation on all the second calibration parameters to obtain a first calibration parameter of the s group of RRUs at the current frequency point.

Optionally, before the network side device respectively combines the first calibration parameters of each group of RRUs at different frequency points to obtain the target calibration parameter of each frequency point on the bandwidth, the method includes:

and the network side equipment selects a reference calibration parameter to align the first calibration parameters of each group of RRUs when the first calibration parameters of each group of RRUs at the current frequency point are not normalized by using the same antenna.

Optionally, the performing, by the network side device, signal transmission compensation according to the antenna corresponding to the target calibration parameter includes:

and the network side equipment compensates the received signals and/or the transmitted signals of the corresponding antenna according to the target calibration parameters of the current frequency point.

Optionally, the compensating, by the network side device, the received signal and/or the transmitted signal of the corresponding antenna according to the target calibration parameter of the current frequency point includes:

and the network side equipment respectively compensates according to the amplitude and the phase of the target calibration parameter corresponding to the second antenna under the condition of compensating the received signal and the transmitted signal of the second antenna.

Optionally, the calibration sequence is transmitted in a guard interval GP.

Optionally, the calibration sequence is transmitted on a resource unit corresponding to an antenna of the RRU, and the resource unit positions corresponding to different antennas of the RRU are different.

Optionally, the connection of all the grouped RRUs is obtained by connecting every two RRUs in each group by using one RRU as a starting point after the RRUs in each group are connected in pairs.

In order to achieve the above object, an embodiment of the present application further provides a calibration processing apparatus, including:

the RRU grouping module is used for grouping a plurality of RRUs, wherein at least one RRU in each group of RRUs belongs to at least one residual group, and all the grouped RRUs are communicated;

the first processing module is used for sequentially selecting each group of RRUs and corresponding target RRUs to mutually transmit a calibration sequence;

the second processing module is used for acquiring a channel estimation result during the transmission of the calibration sequence;

the third processing module is used for obtaining a target calibration parameter according to the channel estimation result;

and the fourth processing module is used for carrying out signal transmission compensation according to the antenna corresponding to the target calibration parameter.

Optionally, the first processing module includes:

the first processing sub-module is used for selecting at least one RRU as a target RRU from the groups except the s group of RRUs under the condition of selecting the s group of RRUs to send the calibration sequence, and the target RRU receives the calibration sequence sent by the s group of RRUs;

a second processing sub-module, configured to receive, by the s-th group of RRUs, a calibration sequence sent by the target RRU when the target RRU sends the calibration sequence;

wherein s is an integer greater than or equal to 1.

Optionally, the second processing module is further configured to:

when the s group of RRUs and the target RRU mutually transmit the calibration sequence, performing channel estimation on a first channel to obtain a first channel estimation result, and performing channel estimation on a second channel to obtain a second channel estimation result;

Optionally, the third processing module includes:

the third processing sub-module is used for obtaining a first calibration parameter of each frequency point of each group of RRUs on the bandwidth according to the channel estimation result corresponding to each group of RRUs;

and the fourth processing sub-module is configured to respectively combine the first calibration parameters of each group of RRUs at different frequency points to obtain the target calibration parameter of each frequency point on the bandwidth.

Optionally, the third processing sub-module includes:

a first calculating unit, configured to calculate all second calibration parameters of an s-th group of RRUs at a current frequency point according to a first channel estimation result and a second channel estimation result of the current frequency point when the s-th group of RRUs and the target RRU transmit calibration sequences to each other;

and the second calculating unit is used for calculating the first calibration parameters of the s group of RRUs at the current frequency point according to all the second calibration parameters.

Optionally, the first computing unit is further configured to:

obtaining a first channel estimation result

Ith row and second channel estimation results of

Wherein i is an integer greater than or equal to 1.

Optionally, the second computing unit is further configured to:

and performing weighted summation on all the second calibration parameters to obtain a first calibration parameter of the s group of RRUs at the current frequency point.

Optionally, the third processing module further includes:

and the fifth processing sub-module is used for selecting a reference calibration parameter to align the first calibration parameters of each group of RRUs when the first calibration parameters of each group of RRUs at the current frequency point are not normalized by using the same antenna.

Optionally, the fourth processing module is further configured to:

and compensating the received signals and/or the transmitted signals of the corresponding antennas according to the target calibration parameters of the current frequency point.

Optionally, the fourth processing module is further configured to:

and respectively compensating according to the amplitude and the phase of the target calibration parameter corresponding to the second antenna under the condition of compensating the receiving signal and the transmitting signal of the second antenna.

Optionally, the calibration sequence is transmitted in a guard interval GP.

In order to achieve the above object, an embodiment of the present application further provides a calibration processing apparatus, including: memory, transceiver, processor: a memory for storing program instructions; a transceiver for transceiving data under the control of the processor; a processor to read program instructions in the memory and perform the following:

grouping a plurality of RRUs (radio remote units), wherein at least one RRU in each group of RRUs belongs to at least one residual group, and all the grouped RRUs are communicated;

sequentially selecting each group of RRUs and corresponding target RRUs to mutually transmit a calibration sequence;

acquiring a channel estimation result during the transmission of the calibration sequence;

obtaining a target calibration parameter according to the channel estimation result;

and performing signal transmission compensation according to the antenna corresponding to the target calibration parameter.

Optionally, the processor is further configured to read the program instructions in the memory and perform the following operations:

under the condition that an s-th group of RRUs is selected to send a calibration sequence, selecting at least one RRU from groups except the s-th group of RRUs as a target RRU, wherein the target RRU receives the calibration sequence sent by the s-th group of RRUs;

under the condition that the target RRU sends a calibration sequence, receiving the calibration sequence sent by the target RRU through the s-th group of RRUs;

wherein s is an integer greater than or equal to 1.

wherein the first channel is a channel for the s-th group of RRUs to send the calibration sequence to the target RRU, and the second channel is a channel for the target RRU to send the calibration sequence to the s-th group of RRUs.

obtaining a first calibration parameter of each frequency point of each group of RRUs on the bandwidth according to the channel estimation result corresponding to each group of RRUs;

and respectively combining the first calibration parameters of each group of RRUs at different frequency points to obtain the target calibration parameters of each frequency point on the bandwidth.

when the s group of RRUs and the target RRU transmit calibration sequences mutually, calculating all second calibration parameters of the s group of RRUs at the current frequency point according to a first channel estimation result and a second channel estimation result of the current frequency point;

and calculating the first calibration parameters of the s group of RRUs at the current frequency point according to all the second calibration parameters.

obtaining a first channel estimation result

Ith row and second channel estimation results of

Wherein i is an integer greater than or equal to 1.

and performing weighted summation on all the second calibration parameters to obtain a first calibration parameter of the s-th group of RRUs at the current frequency point.

and under the condition that the first calibration parameters of each group of RRUs of the current frequency point are not normalized by using the same antenna, selecting a reference calibration parameter to align the first calibration parameters of each group of RRUs.

Optionally, the calibration sequence is transmitted in a guard interval GP.

In order to achieve the above object, an embodiment of the present application further provides a processor-readable storage medium, which stores program instructions for causing the processor to execute the calibration processing method as described above.

The above technical scheme of this application has following beneficial effect at least:

in the technical solution of the embodiment of the application, a plurality of RRUs are grouped to obtain a group through which all the grouped RRUs can be communicated, then each group of RRUs and a corresponding target RRU mutually transmit a calibration sequence, and then a channel estimation result during transmission of the calibration sequence is obtained, and a target calibration parameter is obtained according to the obtained channel estimation result, thereby completing signal transmission compensation for the corresponding antenna. When the multiple RRU antennas are remote, the air interface is used for carrying out antenna calibration between the interior of the RRU and the RRU, and the reduction of system throughput caused by excessive consumption of air interface resources is avoided.

Drawings

FIG. 1 is a schematic flow chart of a method according to an embodiment of the present application;

fig. 2 is a schematic diagram of all RRU connectivity;

FIG. 3 is a schematic diagram of an application of the method according to an embodiment of the present application;

FIG. 4 is a diagram illustrating the timing of the calibration sequence transmission in the embodiment of the present application;

FIG. 5 is a schematic diagram illustrating a mapping position of a calibration sequence in a frequency domain according to an embodiment of the present application;

FIG. 6 is a second exemplary illustration of the mapping positions of the calibration sequences in the frequency domain according to the embodiment of the present application;

FIG. 7 is a third exemplary frequency domain mapping position of the calibration sequence in the embodiment of the present application;

FIG. 8 is a second schematic diagram of an application of the method according to the embodiment of the present application;

FIG. 9 is a diagram illustrating one of the structures of a calibration processing apparatus according to an embodiment of the present application;

fig. 10 is a second structural diagram of a calibration processing apparatus according to an embodiment of the present application.

Detailed Description

In the embodiment of the present application, the term "and/or" describes an association relationship of associated objects, and means that there may be three relationships, for example, a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship.

In the embodiments of the present application, the term "plurality" means two or more, and other terms are similar thereto.

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The embodiment of the application provides a calibration processing method, a calibration processing device and calibration processing equipment. The method and the device are based on the same application concept, and because the principles of solving the problems of the method and the device are similar, the implementation of the device and the method can be mutually referred, and repeated parts are not described again.

As shown in fig. 1, a calibration processing method provided in an embodiment of the present application includes:

step 101, a network side device groups a plurality of remote radio units RRUs, where at least one RRU in each group of RRUs belongs to at least one remaining group, and all the grouped RRUs are connected.

Here, after the network side device is grouped, all the RRUs after grouping can be connected according to the grouping result. That is, in this step, a plurality of RRUs are grouped, so that at least one RRU in each group of RRUs obtained by grouping belongs to at least one remaining group (i.e., other groups in all groups), and all the grouped RRUs are connected, so that all the RRUs are calibrated and aligned, and the calibration effectiveness is ensured.

And 102, the network side equipment sequentially selects each group of RRUs and corresponding target RRUs to mutually transmit a calibration sequence.

Here, the target RRU is at least one RRU of the plurality of RRUs other than the currently selected group of RRUs.

In this step, after completing grouping in step 101, the network side device may sequentially select each group of RRUs and a corresponding target RRU to transmit a calibration sequence to each other, so as to perform a round of calibration for each group.

Step 103, the network side device obtains a channel estimation result during the transmission of the calibration sequence.

In this step, the network side device lays a foundation for obtaining the required target calibration parameter subsequently by obtaining the channel estimation result when the calibration sequence is transmitted in step 102.

And step 104, the network side equipment obtains a target calibration parameter according to the channel estimation result.

In this step, the network side device obtains the target calibration parameter from the channel estimation result obtained in step 103.

And 105, the network side equipment performs signal transmission compensation according to the antenna corresponding to the target calibration parameter.

In this step, after the network side device obtains the target calibration parameter in step 104, the signal transmission compensation can be performed on the corresponding antenna.

Therefore, according to the method in the embodiment of the present application, according to the above steps, a network side device groups a plurality of RRUs to obtain a group through which all the grouped RRUs can be connected, then each group of RRUs and a corresponding target RRU mutually transmit a calibration sequence, and then obtain a channel estimation result when the calibration sequence is transmitted, obtain a target calibration parameter according to the obtained channel estimation result, and complete signal transmission compensation for the corresponding antenna. When multiple RRU antennas are far away, the air interface is used for calibrating the antennas inside the RRUs and between the RRUs, and the reduction of system throughput caused by excessive consumption of air interface resources is avoided.

Optionally, the communication of all the grouped RRUs is obtained by connecting all the RRUs in each group two by using a grouping result, and then sequentially connecting all the RRUs with one RRU as a starting point.

That is, after grouping, if each RRU is used as a node, all RRU nodes can be connected in sequence after the RRU nodes in each group are connected two by two. For example, 5 RRUs are numbered 1,2,3,4, 5 by number, assuming two groups: after the RRU nodes in the two groups are connected two by two, (1, 2, 4) and (4, 5, 3), at least all the RRUs shown in fig. 2 can be connected. However, if the groups are (1, 2, 3) and (4, 5), after two RRU nodes in two groups are connected, all RRUs cannot be connected, that is, the group is not suitable for the present application.

The method in the embodiment of the present application is suitable for Time Division Duplex (TDD) indoor division scenarios.

In this embodiment, multiple RRUs (e.g., X RRUs) may belong to the same cell, and a network side device (e.g., a base station) groups the X RRUs, where the number of RRUs included in each group is greater than or equal to 2, and the RRUs are divided into S groups, where S is an integer greater than or equal to 2. Of course, the S groups of RRUs can enable X RRUs to be connected.

Optionally, step 102 comprises:

the network side equipment receives the calibration sequence sent by the target RRU through the s-th group of RRUs under the condition that the target RRU sends the calibration sequence;

wherein s is an integer greater than or equal to 1.

That is, when the s-th group of RRUs is selected to send the calibration sequence, at least one RRU is selected from other groups (groups other than the s-th group) of all the groups as a target RRU, and the target RRU receives the calibration sequence sent by the s-th group of RRUs; then, the calibration sequence is sent by the target RRU, and the s-th group of RRUs receives the calibration sequence sent by the target RRU. Here, the sending or receiving of the calibration sequence by the s-th group of RRUs means that all RRUs in the s-th group of RRUs send or receive the calibration sequence. The target RRU is R RRUs in other groups, where R is an integer greater than or equal to 1.

In this embodiment, based on the RRU grouping, each group of RRUs and the corresponding target RRUs may be sequentially selected to transmit a calibration sequence to each other, so as to complete the S-round calibration.

Optionally, step 103 comprises:

when the calibration sequence is transmitted between the s-th group of RRUs and the target RRU, the network side equipment performs channel estimation on a first channel to obtain a first channel estimation result, and performs channel estimation on a second channel to obtain a second channel estimation result;

That is, in each calibration, for the current s-th group of RRUs and the corresponding target RRU, channel estimation is performed on the first channel (the channel through which the s-th group of RRUs sends the calibration sequence to the target RRU) and the second channel (the channel through which the target RRU sends the calibration sequence to the s-th group of RRUs), respectively, so as to obtain a first channel estimation result

And second channel estimation result

Here, the first channel and the second channel may be Multiple In Multiple Out (MIMO) wireless channels. When the channel estimation result is recorded, the first channel estimation result on the frequency point f is recorded

And second channel estimation result

Optionally, step 104 comprises:

As can be seen from the above, the channel estimation result corresponding to each RRU group is: and performing channel estimation on the first channel and the second channel of the calibration sequence mutually transmitted by the group of RRUs and the corresponding target RRU to obtain a channel estimation result. Therefore, according to the steps, the network side equipment can obtain first calibration parameters of each frequency point of each group of RRUs on the bandwidth according to the channel estimation result corresponding to each group of RRUs; and then, respectively combining the first calibration parameters of each group of RRUs at different frequency points to obtain target calibration parameters of each frequency point on the bandwidth, thereby completing targeted compensation based on the frequency points during compensation.

In this embodiment, each RRU group has a first calibration parameter c at one frequency point in the bandwidth ^(s) This can be understood as the relative calibration parameters of the RRU group at the frequency point.

Optionally, the obtaining, by the network side device, the first calibration parameter of each frequency point of each group of RRUs on the bandwidth according to the channel estimation result corresponding to each group of RRUs includes:

when the s group of RRUs and the target RRU transmit calibration sequences mutually, the network side equipment calculates all second calibration parameters of the s group of RRUs at the current frequency point according to a first channel estimation result and a second channel estimation result of the current frequency point;

That is, for the s-th group of RRUs, the network side device will first determine according to the current frequency point (e.g. f 1)

And

calculating all second calibration parameters of the s group of RRUs at f 1; then, further according to all the obtained second calibration parameters, calculating a first calibration parameter c of the s group of RRUs at f1 ^(s) 。

Here, the second calibration parameter is determined by

A certain row of

Is determined by the corresponding column of (a). Therefore, optionally, the calculating all second calibration parameters of the s-th group of RRUs at the current frequency point according to the first channel estimation result and the second channel estimation result of the current frequency point includes:

the network side equipment acquires a first channel estimation result

Ith row and second channel estimation results of

Wherein i is an integer greater than or equal to 1.

Here, the first antenna is any antenna of any RRU in the current group of RRUs. Of course, the antennas in the current group of RRUs and the RRUs connected to the most other groups are usually selected for normalization. For example, the above divides 5 RRUs into two groups: in the implementations of (1, 2, 4) and (4, 5, 3), the first antenna of RRU4 may be preferably used as the first antenna.

After obtaining all the second calibration parameters of the current frequency point, optionally, the network side device calculates the first calibration parameters of the second group of RRUs at the current frequency point according to all the second calibration parameters, including:

and the network side equipment performs weighted summation on all the second calibration parameters to obtain a first calibration parameter of the s-th group of RRUs at the current frequency point.

That is, the first calibration parameter of the s-th group of RRUs at the current frequency point

Wherein R is the number of the target RRUs, and M is the number of the antennas of the RRUs. Wherein the first calibration parameter can be further expressed as:

and the calibration parameters of the yth antenna of the xth RRU in the s group of RRUs are shown.

Therefore, first calibration parameters of all RRUs at the current frequency point can be calculated in sequence. And for the target calibration parameter of the current frequency point, the first calibration parameter of each group of RRUs of the current frequency point can be further obtained. Since each group uses a certain antenna in the respective group as a normalized reference factor (reference antenna), the reference antenna needs to be finally aligned to the same reference antenna in order to obtain the target calibration parameter. Of course, if the same antenna normalization is used for each calibration round, the 5 RRUs are divided into two groups as described above: in the implementations of (1, 2, 4) and (4, 5, 3), the first antenna of RRU4 is used as the first antenna in both of the two calibration runs, and each set of coefficients is naturally aligned. Therefore, optionally, before the network side device separately combines the first calibration parameters of each group of RRUs at different frequency points to obtain the target calibration parameter of each frequency point on the bandwidth, the method includes:

and the network side equipment selects a reference calibration parameter to align the first calibration parameters of each group of RRUs under the condition that the first calibration parameters of each group of RRUs of the current frequency point are not normalized by using the same antenna.

Aiming at the condition that the first calibration parameters of each group of RRUs under the current frequency point do not use the same antenna for normalization processing, one reference calibration parameter is selected to align the first calibration parameters of each group of RRUs.

For example, the above divides 5 RRUs into two groups: in the implementation of (1, 2, 4) and (4, 5, 3), if the first round uses the first root antenna of RRU1 for normalization and the second round uses the first root antenna of RRU4 for normalization, the coefficient corresponding to the first root antenna of RRU4 needs to be found in the first calibration parameter of the first round

And multiplies it to all first calibration parameters c of the second round ⁽²⁾ As second round calibration parameters after alignment

After the first calibration parameters of each group of RRUs are aligned, weighting and combining the first calibration parameters of each group of RRUs of the current frequency point to obtain a target calibration parameter of the current frequency point

When the first calibration parameters of each group of RRUs are combined, if the calibration parameters of a certain antenna only appear in the calibration parameters of a certain round, the calibration parameters are the target calibration parameters of the antenna; if the calibration parameter of a certain antenna appears in the calibration parameters of multiple rounds, the average value of the calibration parameters of the antenna is the target calibration parameter of the antenna.

It should be appreciated that the target calibration parameter

c _x,y And representing target calibration parameters of the y antenna of the x RRU.

Next, taking the structure of the network side device including 4 RRUs (RRU 1, RRU2, RRU3, and RRU 4) shown in fig. 3 as an example, the application of the embodiment of the present application is described with reference to fig. 8. Baseband processing unit here, it is assumed that 4 RRUs each have 4 antennas with the same polarization direction, i.e., X =4, m =4. The coverage areas of these antennas intersect, and there is a possibility of distributed MIMO. The network side equipment divides RRU1, RRU2, RRU3 and RRU4 into two groups (1, 2, 3) and (1, 2, 4) according to the grouping requirement.

First round first calibration parameter calculation:

at a first time (designated time), RRU1, RRU2 and RRU3 send calibration sequences, RRU4 receives the calibration sequences, BBU estimates wireless channels from transmitting antennas of RRU 1-RRU 3 to receiving antennas of RRU4, and the channel estimation result on a frequency point f is recorded as H without loss of generality _1→4 (f)，H _2→4 (f)，H _3→4 (f) Then, then

At a second moment (designated moment), the RRU4 sends a calibration sequence, the RRU1, the RRU2 and the RRU3 receive the calibration sequence, the BBU estimates the wireless channels from the transmitting antenna of the RRU4 to the receiving antennas of the RRUs 1 to 3, and the channel estimation result on the frequency point f is recorded as H without loss of generality _4→1 (f)，H _4→2 (f)，H _4→3 (f) Then, then

A BaseBand processing Unit (base band Unit, BBU) calculates first calibration parameters of RRU1, RRU2, and RRU3 at a frequency point f: based on the principle of

Row i and row i of

After dividing by the utilization point in the ith row, normalizing the first antenna of the RRU1 to obtain a second calibration parameter

In this way, i =1,2,3,4 is sequentially taken to obtain all the second calibration parameters. Weighting and summing all the second calibration parameters to obtain the first calibration parameter of the first round

Vector c ⁽¹⁾ Length of 12, representing the relative calibration parameters between the twelve antennas of RRU1, RRU2, and RRU3 normalized by the first antenna of RRU1, the expansion can be expressed as:

second round first calibration parameter calculation:

at a third time (designated time), the RRU1, the RRU2 and the RRU4 send calibration sequences, the RRU3 receives the calibration sequences, the BBU estimates a wireless channel from the transmitting antennas of the RRU1, the RRU2 and the RRU4 to the receiving antenna of the RRU3, and the channel estimation result on the frequency point f is recorded as H without loss of generality _1→3 (f)，H _2→3 (f)，H _4→3 (f) Then, then

At a fourth time (designated time), the RRU3 sends a calibration sequence, the RRU1, the RRU2 and the RRU4 receive the calibration sequence, the BBU estimates the wireless channel from the transmitting antenna of the RRU3 to the receiving antennas of the RRU1, the RRU2 and the RRU4, and the channel estimation result on the frequency point f is recorded as H without loss of generality _3→1 (f)，H _3→2 (f)，H _3→4 (f) Then, then

The BBU calculates first calibration parameters of the RRU1, the RRU2 and the RRU4 at a frequency point f: based on the principle of

Row i and row i of

I =1,2,3,4 are sequentially taken, and all the second calibration parameters are obtained. Weighting and summing all the second calibration parameters to obtain the first calibration parameters of the second round

Vector c ⁽²⁾ Length of 12, representing the relative calibration parameters between the twelve antennas of RRU1, RRU2, and RRU4 normalized by the first antenna of RRU1, the expansion can be expressed as:

and combining the first calibration parameters of the two rounds to obtain a target calibration parameter of the frequency point f. Since in the two rounds of calculation of the first calibration parameter, the first round and the second round are both relative calibration and both use the same antenna (the first antenna of RRU 1) for normalization, the following are directly combined:

1) The first calibration parameter vector length for the first and second round is extended from 12 to 16 (i.e., all antennas containing all RRUs), i.e.

2) Element by element merging c ⁽¹⁾ c ⁽²⁾ To obtain the target calibration parameter of the frequency point f

Wherein, the first and the second end of the pipe are connected with each other,

similarly, the target calibration parameters of each frequency point on the bandwidth can be obtained.

However, performing signal transmission compensation by using the target calibration parameter needs to be performed by using the target calibration parameter for the current frequency point, so optionally, step 105 includes:

and the network side equipment compensates the received signals and/or the transmitted signals of the corresponding antennas according to the target calibration parameters of the current frequency point.

That is, the compensation may be implemented as: receive compensation, transmit compensation, and hybrid compensation.

Wherein, the receiving compensation is to directly compensate the target calibration parameter on the receiving signal of the corresponding antenna

Up, i.e. compensated, received signal

The uplink comprehensive channel after receiving compensation is aligned to the downlink comprehensive channel.

The transmission compensation is to directly compensate the target calibration parameter for the transmission signal of the corresponding antenna

Up, i.e. transmitting signals after compensation

Transmitting compensated downlink comprehensive channel and uplink comprehensive channel phaseAre aligned by pulling.

For hybrid compensation, optionally, the compensating, by the network side device, the received signal and/or the transmitted signal of the corresponding antenna according to the target calibration parameter of the current frequency point includes:

Here, the second antenna is a compensated target antenna. Target calibration parameter c using the second antenna _x,y When the hybrid compensation is performed, only the phase of the target calibration parameter may be compensated at the time of downlink transmission, and the amplitude calibration may be performed at the time of reception. Suppose that

Then

Of course, in the hybrid compensation, the amplitude calibration may be performed during the downlink transmission, and only the phase of the target calibration parameter is compensated during the reception.

It should be appreciated that the air interface calibration process needs to minimize the effect of the variation factor of the radio channel during calibration. The use of resources for the calibration sequence also allows for calibrating as many antennas as possible within the same symbol.

Optionally, in this embodiment, the calibration sequence is transmitted in a guard interval GP.

For example, in a 5G system, the calibration operation may be performed by using GP of TDD, and each symbol is inserted into a calibration sequence of several antennas in a frequency division manner. And (2) proportioning symbols of special time slots by 6:4: for example, fig. 4 shows the sending time of the downlink symbol, GP, uplink symbol and calibration sequence of the special timeslot.

In order to avoid the influence of the calibration sequence on uplink reception, the calibration sequence is transmitted at a position where the GP is close to the downlink.

Assuming that the length of the calibration sequence is one symbol, the calibration sequence transmission interval may be within the range of

GP symbols

7, 8, and 9, and one symbol length may be selected for transmission (preferably, a symbol near the downlink in front of the GP is selected). The receiving end adds a certain propagation delay to the corresponding symbol sending position for receiving. Special time slots of other symbol ratios, and 6;4:4, the ratio is similar, and under the condition of ensuring that the uplink receiving is not influenced, the symbol in front of GP is selected as much as possible to carry out the sending and receiving of the calibration sequence.

In addition, optionally, in this embodiment, the calibration sequence is transmitted on a resource unit corresponding to an antenna of the RRU, and the resource unit positions corresponding to different antennas of the RRU are different.

Specifically, taking the structure of a network side device including 4 RRUs (RRU 1, RRU2, RRU3, and RRU 4) as an example, the implementation of frequency division transmission of different antenna calibration sequences is described. Assume that the antennas of the 4 RRUs are numbered as in table 1 below:

TABLE 1

If the system bandwidth includes N RBs and the calibration sequence length is N, one possible calibration sequence mapping scheme is that the frequency domain interval is 1 RB (12 REs), and the calibration sequence for each antenna is frequency domain mapped in a Frequency Division Multiplexing (FDM) format. Taking the frequency domain RE mapping of the calibration sequences of 4 antennas in RRU1 as an example, the calibration sequences of 4 antennas are respectively mapped to different RE positions, as shown in fig. 5.

Thus, the frequency domain mapping positions of the calibration sequences of the first round of 4 RRUs can be as shown in fig. 6. Referring to fig. 6, the mapping positions of the calibration sequence for the first calibration round are illustrated in table 2 below:

TABLE 2

And the frequency-domain mapping positions of the calibration sequences of the second round of 4 RRUs can be as shown in fig. 7. The calibration sequence mapping positions for the second round of calibration, as shown in connection with fig. 7, are illustrated in table 3 below:

TABLE 3

In summary, the method of the embodiment of the present application may not depend on hardware by performing air interface calibration through multiple rounds of interworking between remote antennas of the network side device, thereby reducing hardware cost; meanwhile, the method does not depend on terminal feedback, and relatively high calibration precision can be obtained only through processing in the network side equipment.

As shown in fig. 9, an embodiment of the present application further provides a calibration processing apparatus, including: memory 920, transceiver 910, processor 900: a memory 920 for storing program instructions; a transceiver 910 for transceiving data under the control of the processor 900; a processor 900 for reading the program instructions in the memory 920 and performing the following operations:

grouping a plurality of RRUs, wherein at least one RRU in each group of RRUs belongs to at least one residual group, and all the grouped RRUs are communicated;

Optionally, the processor 900 is further configured to read the program instructions in the memory 920 and perform the following operations:

under the condition that an s group of RRUs is selected to send a calibration sequence, selecting at least one RRU as a target RRU from groups except the s group of RRUs, wherein the target RRU receives the calibration sequence sent by the s group of RRUs;

wherein s is an integer greater than or equal to 1.

obtaining a first channel estimation result

Ith row and second channel estimation results of

Wherein i is an integer greater than or equal to 1.

Optionally, the calibration sequence is transmitted in a guard interval GP.

Wherein in fig. 9 the bus architecture may include any number of interconnected buses and bridges, with one or more processors, represented by the processor 900, and various circuits, represented by the memory 920, being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 910 may be a number of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium including wireless channels, wired channels, fiber optic cables, and the like. The processor 900 is responsible for managing the bus architecture and general processing, and the memory 920 may store data used by the processor 910 in performing operations.

The processor 900 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), and may also have a multi-core architecture.

In the device in the embodiment of the application, the air interface calibration is carried out by utilizing the multi-round intercommunication among the remote antennas of the network side equipment, so that the hardware is not depended on, and the hardware cost is reduced; meanwhile, the method does not depend on terminal feedback, and relatively high calibration precision can be obtained only through processing in the network side equipment.

It should be noted that the apparatus provided in the embodiment of the present application can implement all the method steps implemented by the method embodiment and achieve the same technical effects, and detailed descriptions of the same parts and beneficial effects as the method embodiment in this embodiment are omitted here.

As shown in fig. 10, the present application also provides a calibration processing apparatus, including:

a grouping module 1010, configured to group multiple remote radio units RRUs, where at least one RRU in each group of RRUs belongs to at least one remaining group, and all the grouped RRUs are connected;

a first processing module 1020, configured to select each group of RRUs and a corresponding target RRU in sequence to transmit a calibration sequence to each other;

a second processing module 1030, configured to obtain a channel estimation result during transmission of the calibration sequence;

a third processing module 1040, configured to obtain a target calibration parameter according to the channel estimation result;

the fourth processing module 1050 is configured to perform signal transmission compensation according to the antenna corresponding to the target calibration parameter.

Optionally, the first processing module includes:

the first processing sub-module is used for selecting at least one RRU as a target RRU from the groups except the s group of RRUs under the condition that the s group of RRUs is selected to send a calibration sequence, and the target RRU receives the calibration sequence sent by the s group of RRUs;

wherein s is an integer greater than or equal to 1.

Optionally, the second processing module is further configured to:

when the s-th group of RRUs and the target RRU mutually transmit the calibration sequence, performing channel estimation on a first channel to obtain a first channel estimation result, and performing channel estimation on a second channel to obtain a second channel estimation result;

Optionally, the third processing module includes:

Optionally, the third processing sub-module includes:

and a second calculating unit, configured to calculate a first calibration parameter of the s-th group of RRUs at the current frequency point according to all the second calibration parameters.

Optionally, the first computing unit is further configured to:

obtaining a first channel estimation result

Ith row and second channel estimation results of

Wherein i is an integer greater than or equal to 1.

Optionally, the second computing unit is further configured to:

Optionally, the third processing module further includes:

and the fifth processing sub-module is used for selecting a reference calibration parameter to align the first calibration parameters of each group of RRUs under the condition that the first calibration parameters of each group of RRUs of the current frequency point are not normalized by using the same antenna.

Optionally, the fourth processing module is further configured to:

Optionally, the calibration sequence is transmitted in a guard interval GP.

According to the device provided by the embodiment of the application, the air interface calibration is carried out by utilizing the multi-round intercommunication among the remote antennas of the network side equipment, so that the hardware is not depended on, and the hardware cost is reduced; meanwhile, the method does not depend on terminal feedback, and relatively high calibration precision can be obtained only through processing in the network side equipment.

It should be noted that the division of the unit in the embodiment of the present application is schematic, and is only a logic function division, and there may be another division manner in actual implementation. In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit may be implemented in the form of hardware, or may also be implemented in the form of a software functional unit.

The integrated unit, if implemented as a software functional unit and sold or used as a stand-alone product, may be stored in a processor readable storage medium. Based on such understanding, the technical solution of the present application may be substantially implemented or contributed by the prior art, or all or part of the technical solution may be embodied in a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, a network device, or the like) or a processor (processor) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

It should be noted that the apparatus provided in the embodiment of the present application can implement all the method steps implemented by the method embodiment and achieve the same technical effect, and detailed descriptions of the same parts and beneficial effects as the method embodiment in this embodiment are omitted here.

In some embodiments of the present application, there is also provided a processor-readable storage medium storing program instructions for causing a processor to perform the steps of:

When executed by the processor, the program instructions may implement all the implementation manners in the embodiment of the method applied to the network-side device shown in fig. 1, and are not described herein again to avoid repetition.

The technical scheme provided by the embodiment of the application can be suitable for various systems, particularly 5G systems. For example, the applicable System may be a Global System for Mobile communications (GSM) System, a Code Division Multiple Access (CDMA) System, a Wideband Code Division Multiple Access (WCDMA) General Packet Radio Service (General Packet Radio Service, GPRS) System, a Long Term Evolution (Long Term Evolution, LTE) System, a LTE Frequency Division Duplex (Frequency Division Duplex, FDD) System, a LTE Time Division Duplex (TDD) System, a Long Term Evolution (Long Term Evolution Access, LTE-a) System, a Universal Mobile Telecommunications System (UMTS), a Universal Mobile telecommunications Access (WiMAX) System, a New Radio network Access (NR 5, new Radio Network (NR) System, etc. These various systems include terminal devices and network devices. The System may further include a core network portion, such as an Evolved Packet System (EPS), a 5G System (5 GS), and the like.

The terminal referred to in the embodiments of the present application may refer to a device providing voice and/or data connectivity to a user, a handheld device having a wireless connection function, or other processing device connected to a wireless modem. In different systems, the names of the terminal devices may be different, for example, in a 5G system, the terminal device may be called a User Equipment (UE). A wireless terminal device, which may be a mobile terminal device such as a mobile phone (or called a "cellular" phone) and a computer having a mobile terminal device, for example, a portable, pocket, hand-held, computer-included or vehicle-mounted mobile device, may communicate with one or more Core Networks (CNs) via a Radio Access Network (RAN), and may exchange languages and/or data with the RAN. Examples of such devices include Personal Communication Service (PCS) phones, cordless phones, session Initiation Protocol (SIP) phones, wireless Local Loop (WLL) stations, and Personal Digital Assistants (PDAs). The wireless terminal device may also be referred to as a system, a subscriber unit (subscriber unit), a subscriber station (subscriber station), a mobile station (mobile), a remote station (remote station), an access point (access point), a remote terminal device (remote terminal), an access terminal device (access terminal), a user terminal device (user terminal), a user agent (user agent), and a user device (user device), which are not limited in this embodiment of the present application.

The network side device according to the embodiment of the present application may be a base station, and the base station may include multiple cells that provide services for a terminal. A base station may also be called an access point, or may be a device in an access network that communicates over the air-interface, through one or more sectors, with wireless terminal devices, or by other names, depending on the particular application. The network device may be configured to exchange received air frames with Internet Protocol (IP) packets as a router between the wireless terminal device and the rest of the access network, which may include an Internet Protocol (IP) communication network. The network device may also coordinate attribute management for the air interface. For example, the network device according to the embodiment of the present application may be a Base Transceiver Station (BTS) in a Global System for Mobile communications (GSM) or a Code Division Multiple Access (CDMA), may be a network device (NodeB) in a Wideband Code Division Multiple Access (WCDMA), may be an evolved Node B (eNB or e-NodeB) in a Long Term Evolution (Long Term Evolution, LTE) System, may be a 5G Base Station (gNB) in a 5G network architecture (next Evolution System), may be a Home evolved Node B (Home B, heNB), a relay Node (relay Node), a Home Base Station (femto), a pico Base Station (pico) and the like, and is not limited in the embodiments of the present application. In some network architectures, network devices may include Centralized Unit (CU) nodes and Distributed Unit (DU) nodes, which may also be geographically separated.

The network side device and the terminal may each use one or more antennas to perform Multiple Input Multiple Output (MIMO) transmission, where the MIMO transmission may be Single User MIMO (SU-MIMO) or Multi-User MIMO (MU-MIMO). The MIMO transmission may be 2D-MIMO, 3D-MIMO, FD-MIMO, or massive-MIMO, or may be diversity transmission, precoding transmission, beamforming transmission, or the like, depending on the form and number of root antenna combinations.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer-executable instructions. These computer-executable instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These processor-executable instructions may also be stored in a processor-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the processor-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These processor-executable instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the spirit and scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.

Claims

1. A method of calibration processing, comprising:

the method comprises the steps that network side equipment groups a plurality of RRUs, wherein at least one RRU in each group of RRUs belongs to at least one residual group, and all the grouped RRUs are communicated;

2. The method of claim 1, wherein the network side device sequentially selects each RRU group and a corresponding target RRU to transmit the calibration sequence to each other, and the method includes:

wherein s is an integer greater than or equal to 1.

3. The method according to claim 1, wherein the obtaining, by the network side device, the channel estimation result at the time of the calibration sequence transmission includes:

4. The method of claim 1, wherein the obtaining, by the network-side device, the target calibration parameter according to the channel estimation result comprises:

5. The method of claim 4, wherein the obtaining, by the network side device, the first calibration parameter of each frequency point of each group of RRUs on the bandwidth according to the channel estimation result corresponding to each group of RRUs comprises:

6. The method of claim 5, wherein the calculating all second calibration parameters of the s-th group of RRUs at the current frequency point according to the first channel estimation result and the second channel estimation result of the current frequency point comprises:

the network side equipment acquires a first channel estimation result

Ith row and second channel estimation results of

Wherein i is an integer greater than or equal to 1.

7. The method of claim 5, wherein the calculating, by the network side device, the first calibration parameter of the s-th group of RRUs at the current frequency point according to all the second calibration parameters comprises:

8. The method of claim 4, wherein before the network side device combines the first calibration parameters of each RRU group at different frequency points, respectively, to obtain the target calibration parameter at each frequency point on the bandwidth, the method includes:

9. The method according to claim 1, wherein the performing, by the network device, signal transmission compensation according to the antenna corresponding to the target calibration parameter includes:

10. The method according to claim 9, wherein the network side device compensates the received signal and/or the transmitted signal of the corresponding antenna according to the target calibration parameter of the current frequency point, and includes:

11. Method according to claim 1, characterized in that the calibration sequence is transmitted in a guard interval GP.

12. The method of claim 1, wherein the calibration sequence is transmitted on a resource unit corresponding to an antenna of the RRU, and the resource unit corresponding to different antennas of the RRU are located at different positions.

13. The method of claim 1, wherein the connection of all the grouped RRUs is obtained by connecting all the RRUs in each group two by using a grouping result and sequentially connecting all the RRUs with one RRU as a starting point.

14. A calibration processing apparatus, comprising:

15. A calibration processing apparatus, characterized by comprising: a memory, a transceiver, a processor;

a memory for storing program instructions; a transceiver for transceiving data under control of the processor; a processor to read program instructions in the memory and perform the following:

16. The apparatus of claim 15, wherein the processor is further configured to read the program instructions in the memory and perform the following operations:

wherein s is an integer greater than or equal to 1.

17. The apparatus of claim 15, wherein the processor is further configured to read program instructions in the memory and perform the following:

18. The apparatus of claim 15, wherein the processor is further configured to read the program instructions in the memory and perform the following:

19. The apparatus of claim 18, wherein the processor is further configured to read the program instructions in the memory and perform the following operations:

20. The apparatus of claim 19, wherein the processor is further configured to read the program instructions in the memory and perform the following operations:

obtaining a first channel estimation result

Ith row and second channel estimation results of

Wherein i is an integer greater than or equal to 1.

21. The apparatus of claim 19, wherein the processor is further configured to read the program instructions in the memory and perform the following operations:

22. The apparatus of claim 18, wherein the processor is further configured to read the program instructions in the memory and perform the following operations:

23. The apparatus of claim 15, wherein the processor is further configured to read the program instructions in the memory and perform the following:

24. The apparatus of claim 23, wherein the processor is further configured to read the program instructions in the memory and perform the following:

25. The apparatus according to claim 15, characterized in that the calibration sequence is transmitted in a guard interval GP.

26. The apparatus of claim 15, wherein the calibration sequence is transmitted on a resource unit corresponding to an antenna of an RRU, and wherein the resource unit corresponding to different antennas of the RRU are located at different positions.

27. The apparatus of claim 14, wherein the connection of all the grouped RRUs is obtained by connecting all the RRUs in each group two by two and then sequentially connecting all the RRUs with one RRU as a starting point through a grouping result.

28. A processor-readable storage medium, characterized in that the processor-readable storage medium stores a computer program for causing a processor to execute the calibration processing method of any one of claims 1 to 13.