CN113904738A - Method and equipment for scheduling antenna calibration time-frequency resources under distributed multi-input multi-output - Google Patents

Method and equipment for scheduling antenna calibration time-frequency resources under distributed multi-input multi-output Download PDF

Info

Publication number
CN113904738A
CN113904738A CN202010640384.9A CN202010640384A CN113904738A CN 113904738 A CN113904738 A CN 113904738A CN 202010640384 A CN202010640384 A CN 202010640384A CN 113904738 A CN113904738 A CN 113904738A
Authority
CN
China
Prior art keywords
radio frequency
cluster
calibration
frequency unit
level
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202010640384.9A
Other languages
Chinese (zh)
Inventor
孙立新
周明宇
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Baicells Technologies Co Ltd
Original Assignee
Baicells Technologies Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Baicells Technologies Co Ltd filed Critical Baicells Technologies Co Ltd
Priority to CN202010640384.9A priority Critical patent/CN113904738A/en
Priority to PCT/CN2020/134479 priority patent/WO2022007324A1/en
Publication of CN113904738A publication Critical patent/CN113904738A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B17/00—Monitoring; Testing
    • H04B17/10—Monitoring; Testing of transmitters
    • H04B17/11—Monitoring; Testing of transmitters for calibration
    • H04B17/12—Monitoring; Testing of transmitters for calibration of transmit antennas, e.g. of the amplitude or phase
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B17/00—Monitoring; Testing
    • H04B17/20—Monitoring; Testing of receivers
    • H04B17/21—Monitoring; Testing of receivers for calibration; for correcting measurements
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/0413—MIMO systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/12—Frequency diversity
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W24/00—Supervisory, monitoring or testing arrangements
    • H04W24/02—Arrangements for optimising operational condition

Abstract

The invention discloses a method and a system for scheduling antenna calibration time-frequency resources under distributed multi-input multi-output, which comprises the following steps: classifying a plurality of radio frequency units in a cooperation range according to a preset rule, and clustering by taking the radio frequency unit at the upper stage of the radio frequency unit at the same stage as a central node; the radio frequency unit in the cooperation range transmits and receives the calibration sequence in an inter-stage and inter-cluster time-frequency domain scheduling mode according to the division condition of the radio frequency unit; determining the range of the radio frequency unit for retransmitting and receiving the calibration sequence according to the interference degree of the interstage sending and receiving calibration sequence, dividing the time domain stage of the calibration of the radio frequency unit in the cooperation range, and sending and receiving the calibration sequence in a set time domain stage in the interstage and inter-cluster time-frequency domain scheduling mode; a final calibration factor is calculated from the radio unit level. By adopting the method and the device, the multiplexing time domain resources can be used as much as possible on the basis of reducing the calibration error, and the efficient scheduling of the antenna calibration can be realized under the scene of multi-node cooperation.

Description

Method and equipment for scheduling antenna calibration time-frequency resources under distributed multi-input multi-output
Technical Field
The invention relates to the technical field of wireless communication, in particular to a method and equipment for scheduling antenna calibration time-frequency resources under distributed multi-input multi-output.
Background
In order to meet the rapid increase of wireless data service demands and the challenges brought by new service demands, a new generation of wireless network in the future needs to support scenes such as high quality, high transmission rate, high user density, high mobility, low time delay and the like. The MIMO (Multiple-Input Multiple-Output) technology equipped with a large-scale antenna array can greatly improve the system capacity, and is one of the key technologies of a new generation of wireless networks in the future. It is a great challenge to arrange so many antennas at a single base station, and it is a practical solution to combine large-scale array distributed placement to serve users. The DMIMO (Distributed MIMO) networking technology, in which a plurality of Distributed radio frequency units jointly transmit to form a massive MIMO downlink, is a new structure of a future wireless access network.
The disadvantage of the prior art is that the prior DMIMO has calibration errors.
Disclosure of Invention
The invention provides a method and a system for scheduling time-frequency resources for antenna calibration under distributed multi-input multi-output, a method and a device for sending calibration sequences, a radio frequency unit and a medium, which are used for solving the problem of calibration errors of the conventional DMIMO.
The invention provides the following technical scheme:
a time-frequency resource scheduling method for antenna calibration under DMIMO comprises the following steps:
classifying a plurality of radio frequency units in a cooperation range according to a preset rule, and clustering by taking the radio frequency unit at the upper stage of the radio frequency unit at the same stage as a central node;
the radio frequency unit in the cooperation range transmits and receives the calibration sequence in an inter-stage and inter-cluster time-frequency domain scheduling mode according to the division condition of the radio frequency unit;
determining the range of the radio frequency unit for retransmitting and receiving the calibration sequence according to the interference degree of the interstage sending and receiving calibration sequence, dividing the time domain stage of the calibration of the radio frequency unit in the cooperation range, and sending and receiving the calibration sequence in a set time domain stage in the interstage and inter-cluster time-frequency domain scheduling mode;
a final calibration factor is calculated from the radio unit level.
In an implementation, the ranking a plurality of radio frequency units in a cooperation range according to a predetermined rule includes:
determining a central node in a cooperation range, taking the central node as a level 1 node, and taking the level 1 node as a center to serve as a cluster, so as to obtain a level 1 cluster;
taking nodes in the cluster except the central node as a level 2 node, taking the level 2 node as the center and the cluster outside the level 1 cluster to obtain a level 2 cluster;
taking the nodes in the cluster except the central node as the 3 rd level nodes, and so on, taking the nth level node as the center and the cluster outside the nth-1 level cluster as the nth level cluster, and taking the nodes in the cluster except the central node as the n +1 level nodes.
In implementation, the level 1 node is determined as follows:
the center of a radio frequency unit distribution area is used as a circle center, a preset threshold value is used as a radius to serve as a cluster, radio frequency units in the cluster are used as the center to serve as the cluster, and each cluster comprises the radio frequency units with the higher number and serves as a level 1 node in a cooperation range.
In practice, the final calibration factor is determined as follows:
and performing antenna calibration in the cluster by taking the cluster center node as a reference radio frequency unit, wherein the cluster calibration factor is the product of the cluster calibration factor and the factor obtained by the previous-stage cluster calibration of the cluster center node.
In an implementation, the inter-stage and inter-cluster time domain scheduling method includes:
the stages transmit and receive calibration sequences in the same time slot.
In an implementation, the inter-stage and inter-cluster frequency domain scheduling modes include:
and when the odd-level nodes send the calibration sequences to the even-level nodes, sending the calibration sequences at different frequency points, determining the frequency point utilization number according to the degrees of the even-level nodes, and otherwise, sending the calibration sequences at the same rule.
In the implementation, the time domain stage division is performed on the radio frequency units in the system according to the interference degree of the inter-stage transmitting and receiving calibration sequence, and the time domain stage division comprises the following steps:
in a network divided into n-level clusters, comparing from level 2, performing time domain stage division: and the kth-level node receives the calibration sequence, receives signal interference of nodes of the kth-3 level or the kth +3 level and the like, and if the signal-to-interference-and-noise ratio of the received useful signal is lower than a preset threshold, the cluster where the useful signal is located is enabled to perform antenna calibration again in the next time domain stage, otherwise, the calibration result is used as the final calibration result of the cluster where the useful signal is located.
A time-frequency resource scheduling system for antenna calibration under DMIMO comprises:
the hierarchical clustering module is used for classifying a plurality of radio frequency units in the cooperation range according to a preset rule, and clustering by taking the radio frequency unit at the upper level of the radio frequency unit at the same level as a central node;
the scheduling module is used for transmitting and receiving the calibration sequence by the radio frequency unit in the cooperation range in an inter-stage and inter-cluster time-frequency domain scheduling mode according to the division condition of the radio frequency unit;
the re-dividing module is used for determining the range of the radio frequency unit for re-sending and receiving the calibration sequence according to the interference degree of the inter-stage sending and receiving calibration sequence, dividing the calibration of the radio frequency unit in the cooperation range in a time domain stage, and sending and receiving the calibration sequence in a set time domain stage in the inter-stage and cluster time-frequency domain scheduling mode;
and the calibration factor calculation module is used for calculating a final calibration factor according to the radio frequency unit level.
In an implementation, the hierarchical clustering module is further configured to rank a plurality of radio frequency units within the cooperation range according to a predetermined rule in the following manner:
determining a central node in a cooperation range, taking the central node as a level 1 node, and taking the level 1 node as a center to serve as a cluster, so as to obtain a level 1 cluster;
taking nodes in the cluster except the central node as a level 2 node, taking the level 2 node as the center and the cluster outside the level 1 cluster to obtain a level 2 cluster;
taking the nodes in the cluster except the central node as the 3 rd level nodes, and so on, taking the nth level node as the center and the cluster outside the nth-1 level cluster as the nth level cluster, and taking the nodes in the cluster except the central node as the n +1 level nodes.
In an implementation, the hierarchical clustering module is further configured to determine the level 1 node as follows:
the center of a radio frequency unit distribution area is used as a circle center, a preset threshold value is used as a radius to serve as a cluster, radio frequency units in the cluster are used as the center to serve as the cluster, and each cluster comprises the radio frequency units with the higher number and serves as a level 1 node in a cooperation range.
In an implementation, the calibration factor calculation module is further configured to determine the final calibration factor as follows:
and performing antenna calibration in the cluster by taking the cluster center node as a reference radio frequency unit, wherein the cluster calibration factor is the product of the cluster calibration factor and the factor obtained by the previous-stage cluster calibration of the cluster center node.
In an implementation, the scheduling module is further configured to perform inter-stage and inter-cluster time domain scheduling in the following manner:
the stages transmit and receive calibration sequences in the same time slot.
In an implementation, the scheduling module is further configured to perform inter-stage and inter-cluster frequency domain scheduling in the following manner:
and when the odd-level nodes send the calibration sequences to the even-level nodes, sending the calibration sequences at different frequency points, determining the frequency point utilization number according to the degrees of the even-level nodes, and otherwise, sending the calibration sequences at the same rule.
In an implementation, the re-partition module is further configured to perform time domain stage partition on the radio frequency units in the system according to the interference degree of the inter-stage transmission/reception calibration sequence in the following manner:
in a network divided into n-level clusters, comparing from level 2, performing time domain stage division: and the kth-level node receives the calibration sequence, receives signal interference of nodes of the kth-3 level or the kth +3 level and the like, and if the signal-to-interference-and-noise ratio of the received useful signal is lower than a preset threshold, the cluster where the useful signal is located is enabled to perform antenna calibration again in the next time domain stage, otherwise, the calibration result is used as the final calibration result of the cluster where the useful signal is located.
A calibration sequence sending method, comprising:
the radio frequency unit determines a calibration sequence to be sent and receives the radio frequency units of the calibration sequence, wherein each radio frequency unit is composed according to DMIMO networking technology, each radio frequency unit is divided into at least two stages, the radio frequency unit of the same stage is clustered by taking the radio frequency unit of the previous stage as a central reference node, the radio frequency unit for receiving the calibration sequence is a central reference node, and a plurality of radio frequency units for sending the calibration sequence and one radio frequency unit for receiving the calibration sequence form a cluster;
the radio unit transmits the calibration sequence to the radio unit that receives the calibration sequence.
In practice, the radio frequency units are classified according to the geographic positions when being classified.
In implementation, the radio frequency units in the same cluster transmit the calibration sequence using the same frequency domain resources and/or time resources to the radio frequency units receiving the calibration sequence, which are different from other clusters and/or other hierarchical radio frequency units.
In implementation, the preset value of cluster radius of the clusters is adjusted according to the number of frequency domain resources.
In an implementation, the method further comprises the following steps:
and determining the cluster radius of the cluster according to the interference degree of the inter-stage transmitting and receiving calibration sequence.
In implementation, the highest level of radio frequency unit is the radio frequency unit in the cluster containing the highest number of radio frequency units in each cluster.
A radio frequency unit, comprising:
a processor for reading the program in the memory, performing the following processes:
determining a calibration sequence to be sent and radio frequency units for receiving the calibration sequence, wherein each radio frequency unit is formed according to a DMIMO networking technology and is divided into at least two stages, the radio frequency units of the same stage are clustered by taking the radio frequency unit of the previous stage as a central reference node, the radio frequency unit for receiving the calibration sequence is a central reference node, and a plurality of radio frequency units for sending the calibration sequence and one radio frequency unit for receiving the calibration sequence form a cluster;
transmitting a calibration sequence to a radio frequency unit receiving the calibration sequence;
a transceiver for receiving and transmitting data under the control of the processor.
In practice, the radio frequency units are classified according to the geographic positions when being classified.
In implementation, the radio frequency units in the same cluster transmit the calibration sequence using the same frequency domain resources and/or time resources to the radio frequency units receiving the calibration sequence, which are different from other clusters and/or other hierarchical radio frequency units.
In implementation, the preset value of cluster radius of the clusters is adjusted according to the number of frequency domain resources.
In an implementation, the method further comprises the following steps:
and determining the cluster radius of the cluster according to the interference degree of the inter-stage transmitting and receiving calibration sequence.
In implementation, the highest level of radio frequency unit is the radio frequency unit in the cluster containing the highest number of radio frequency units in each cluster.
A calibration sequence transmitting apparatus comprising:
the device comprises a determining module, a receiving module and a transmitting module, wherein the determining module is used for determining a calibration sequence to be transmitted and radio frequency units for receiving the calibration sequence, each radio frequency unit is formed according to a DMIMO networking technology and is divided into at least two stages, the radio frequency unit at the same stage is clustered by taking the radio frequency unit at the upper stage as a central reference node, the radio frequency unit for receiving the calibration sequence is the central reference node, and a plurality of radio frequency units for transmitting the calibration sequence and one radio frequency unit for receiving the calibration sequence form a cluster;
and the sending module is used for sending the calibration sequence to the radio frequency unit receiving the calibration sequence.
In practice, the radio frequency units are classified according to the geographic positions when being classified.
In an implementation, the sending module is further configured to use the same frequency domain resource and/or the same time resource when the radio frequency unit in the same cluster sends the calibration sequence to the radio frequency unit that receives the calibration sequence, and the frequency domain resource and/or the time resource are different from the radio frequency units in other clusters and/or other hierarchies.
In implementation, the preset value of cluster radius of the clusters is adjusted according to the number of frequency domain resources.
In an implementation, the method further comprises the following steps:
and determining the cluster radius of the cluster according to the interference degree of the inter-stage transmitting and receiving calibration sequence.
In implementation, the highest level of radio frequency unit is the radio frequency unit in the cluster containing the highest number of radio frequency units in each cluster.
A computer-readable storage medium, characterized in that the computer-readable storage medium stores a computer program for executing the above-described calibration sequence transmission method.
The invention has the following beneficial effects:
in the technical scheme provided by the invention, due to the fact that the antenna calibration time-frequency resource scheduling of the calibration error is considered, the scheme that the radio frequency units are clustered and the global calibration is carried out step by step can avoid the situation that the calibration error is overlarge due to the fact that the radio frequency unit arrays with the calibration relation are dispersed in position, the calibration period can be shortened as far as possible when the graded radio frequency units send the calibration sequences in the time domain stage simultaneously, and the interference can be avoided when the frequency domain division is carried out on the radio frequency units sending the calibration sequences simultaneously, so that the time domain resources can be multiplexed as much as possible on the basis of reducing the calibration error, and the efficient scheduling of the antenna calibration can be realized under the scene of multi-node cooperation.
Each radio frequency unit is formed according to DMIMO networking technology, each radio frequency unit is divided into at least two stages, the radio frequency units of the same stage are clustered by taking the radio frequency unit of the previous stage as a central reference node, the radio frequency unit for receiving the calibration sequence is a central reference node, and a plurality of radio frequency units for sending the calibration sequence and one radio frequency unit for receiving the calibration sequence form a cluster; the radio frequency unit sends the calibration sequence to the radio frequency units which receive the calibration sequence in the same cluster, and the radio frequency units are clustered and calibrated step by step, so that the aim of global calibration is fulfilled, and overlarge calibration errors caused by the position dispersion of the radio frequency unit arrays with calibration relations are avoided;
furthermore, in order to ensure the accuracy of receiving the calibration sequence between stages, the radio frequency units are divided into time domains according to the interference degree between stages, the inter-stage radio frequency units simultaneously transmit the calibration sequence to shorten the calibration period as much as possible, and the radio frequency units simultaneously transmitting the calibration sequence are divided into frequency domains to avoid interference.
Furthermore, due to the fact that the scheduling of the antenna calibration time-frequency resources considering the calibration errors is taken into consideration, the radio frequency units are clustered and the process of carrying out global calibration step by step can avoid the fact that the calibration errors of the radio frequency unit arrays with calibration relations are too large due to position dispersion, the calibration period can be shortened as much as possible when the graded radio frequency units send the calibration sequences in the time domain stage, and the radio frequency units sending the calibration sequences simultaneously are divided in the frequency domain to avoid interference, so that the time domain resources can be reused as much as possible on the basis of reducing the calibration errors, and the efficient scheduling of the antenna calibration can be realized in the multi-node cooperation scene.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:
fig. 1 is a schematic flow chart of an implementation of a time-frequency resource scheduling method for antenna calibration under DMIMO in an embodiment of the present invention;
fig. 2 is a schematic diagram of an implementation flow of a calibration sequence sending method according to an embodiment of the present invention;
FIG. 3 is a schematic flow chart illustrating an implementation of determining a calibration factor according to an embodiment of the present invention;
FIG. 4 is a schematic view of a DMIMO system scenario in an embodiment of the present invention;
FIG. 5 is a diagram illustrating the transceiving of calibration sequences in the time domain phase according to an embodiment of the present invention;
FIG. 6 is a schematic diagram of time domain phase division according to an embodiment of the present invention;
FIG. 7 is a time-frequency resource scheduling system for antenna calibration under DMIMO according to an embodiment of the present invention;
FIG. 8 is a schematic diagram of an embodiment of a radio frequency unit;
fig. 9 is a schematic structural diagram of a calibration sequence sending apparatus according to an embodiment of the present invention.
Detailed Description
The inventor notices in the process of invention that:
the channel reciprocity plays an important role in a large-scale antenna system which is applied in a TDD (Time Division Duplex) mode, although uplink and downlink are carried in the same frequency in the TDD mode, generally, the physical channel gains are considered to be the same, in an actual circuit, the transmitting and receiving processes of the channel need to pass through a radio frequency link module, the radio frequency links received and transmitted by each antenna are respectively completed by different circuits, and the characteristics of the transmitting and receiving circuits are difficult to be completely consistent. In addition, because the environmental temperature and humidity of the transmitting and receiving circuits are different, the characteristics of the two circuits cannot be completely the same, so that the reciprocity of the channels is damaged. Therefore, antenna calibration techniques that compensate for the loss of channel reciprocity are particularly important for DMIMO systems.
Considering that the RF (Radio Frequency) link mismatch at the Radio Frequency unit end has the largest impact on the system performance and the calibration scheme using user feedback has a very large overhead, the antenna calibration between Radio Frequency units in the DMIMO system is usually completed by a method of transmitting and receiving calibration sequences between Radio Frequency units.
In the prior art, a main scheme for global antenna calibration is to fix a reference radio frequency unit and send a calibration sequence to an antenna to be calibrated, and the scheme can cause extremely high calibration errors in a scene that the array positions of DMIMO radio frequency units are scattered.
In addition, the adjacent calibration scheme and the grouping calibration scheme which adopt the non-fixed reference radio frequency unit and are designed for the distributed antenna array can reduce the error of each calibration, but the accumulated error and the time complexity of the distributed antenna array are increased along with the increase of the number of nodes.
Due to the large-scale cooperation in the DMIMO system, the number of stations is increased, and higher requirements are put forward on the antenna calibration period and the antenna calibration performance. Therefore, aiming at the problems of overhigh time complexity and overlong calibration period in the prior art and the calibration error of the distributed antenna array needs to be considered when designing the antenna calibration scheme, the embodiment of the invention provides the antenna calibration time-frequency resource scheduling scheme considering the calibration error, wherein the radio frequency units are clustered and calibrated step by step, so that the aim of global calibration is fulfilled, and the problem of overlarge calibration error caused by the dispersion of the positions of the radio frequency unit arrays with calibration relations is avoided; in order to ensure the accuracy of receiving the calibration sequence between stages, the radio frequency units are divided in time domain stages according to the interference degree between stages, the radio frequency units in stages simultaneously transmit the calibration sequence to shorten the calibration period as much as possible, and the radio frequency units simultaneously transmitting the calibration sequence are divided in frequency domain to avoid interference.
The following describes embodiments of the present invention with reference to the drawings.
In the course of the description, reference will be made to the radio unit transmitting the calibration sequence and the radio unit receiving the calibration sequence, respectively, and then an example of the implementation of the two will be given to better understand the implementation of the scheme given in the embodiment of the present invention. Such an explanation does not mean that the two units must be implemented together or separately, and actually, when the rf unit transmitting the calibration sequence and the rf unit receiving the calibration sequence are implemented separately, they also solve the problem on their own side, and when the two units are used in combination, a better technical effect is obtained.
The following description is from the perspective of the DMIMO system.
Fig. 1 is a schematic diagram of an implementation flow of a time-frequency resource scheduling method for antenna calibration under DMIMO, and as shown in the figure, the method may include:
step 101, a plurality of radio frequency units in a cooperation range are classified according to a preset rule, and the radio frequency units at the same level are clustered by taking the radio frequency units at the upper level as central nodes;
102, transmitting and receiving a calibration sequence by a radio frequency unit in a cooperation range in an inter-stage and inter-cluster time-frequency domain scheduling mode according to the division condition of the radio frequency unit;
103, determining the radio frequency unit range for retransmitting and receiving the calibration sequence according to the interference degree of the interstage transmission and reception calibration sequence, dividing the calibration of the radio frequency unit in the cooperation range in a time domain stage, and transmitting and receiving the calibration sequence in a set time domain stage in the interstage and inter-cluster time-frequency domain scheduling mode;
and 104, calculating a final calibration factor according to the radio frequency unit level.
Specifically, when time-frequency resources for antenna calibration are scheduled under DMIMO, all radio frequency units in a cooperation range can be classified according to a certain rule, and the radio frequency units at the same level are clustered by taking the radio frequency units at the level above as central nodes; the radio frequency unit in the system transmits and receives the calibration sequence by an inter-stage and inter-cluster time-frequency domain scheduling method according to the division condition; determining the range of the radio frequency unit for retransmitting and receiving the calibration sequence according to the interference degree of the interstage sending and receiving calibration sequence, thereby dividing the time domain stage of the calibration of the radio frequency unit in the system, and sending and receiving the calibration sequence by the interstage and inter-cluster time-frequency domain scheduling method in the set time domain stage; a final calibration factor is calculated from the radio unit level.
In an implementation, the ranking a plurality of radio frequency units in a cooperation range according to a predetermined rule includes:
determining a central node in a cooperation range, taking the central node as a level 1 node, and taking the level 1 node as a center to serve as a cluster, so as to obtain a level 1 cluster;
taking nodes in the cluster except the central node as a level 2 node, taking the level 2 node as the center and the cluster outside the level 1 cluster to obtain a level 2 cluster;
taking the nodes in the cluster except the central node as the 3 rd level nodes, and so on, taking the nth level node as the center and the cluster outside the nth-1 level cluster as the nth level cluster, and taking the nodes in the cluster except the central node as the n +1 level nodes.
Specifically, when the radio frequency unit is classified according to a certain standard, a central node in the cooperation range can be found, the central node is a level 1 node, the level 1 node is used as a cluster as a center and is called a level 1 cluster, an intra-cluster node (except the center) is a level 2 node, a cluster which is centered on the level 2 node and outside the level 1 cluster is called a level 2 cluster, an intra-cluster node (except the center) is called a level 3 node, and so on, a cluster which is centered on the level n node and outside the level n-1 cluster is called a level n cluster, and an intra-cluster node (except the center) is called a level n +1 node.
In implementation, the level 1 node is determined as follows:
the center of a radio frequency unit distribution area is used as a circle center, a preset threshold value is used as a radius to serve as a cluster, radio frequency units in the cluster are used as the center to serve as the cluster, and each cluster comprises the radio frequency units with the higher number and serves as a level 1 node in a cooperation range.
Specifically, when the criterion of selecting the central node is performed, the center of the distribution area of the radio frequency units may be used as the center of a circle, a certain threshold may be used as a radius for clustering, the radio frequency units in the clusters are used as the center for clustering, and each cluster including the one with a higher number of radio frequency units will be used as the level 1 node in the cooperation range.
In practice, the final calibration factor is determined as follows:
and performing antenna calibration in the cluster by taking the cluster center node as a reference radio frequency unit, wherein the cluster calibration factor is the product of the cluster calibration factor and the factor obtained by the previous-stage cluster calibration of the cluster center node.
Specifically, when the cluster center node is used as a reference radio frequency unit to perform antenna calibration in the cluster, the calibration factor of the cluster is related to the cluster level, that is, the cluster calibration factor is the product of the in-cluster calibration factor and the factor obtained by the previous-level cluster calibration of the cluster center node.
In an implementation, the inter-stage and inter-cluster time domain scheduling method includes:
the stages transmit and receive calibration sequences in the same time slot.
Specifically, during inter-stage and inter-cluster time domain scheduling, the calibration sequence may be transmitted and received at the same time slot at different stages.
In an implementation, the inter-stage and inter-cluster frequency domain scheduling modes include:
and when the odd-level nodes send the calibration sequences to the even-level nodes, sending the calibration sequences at different frequency points, determining the frequency point utilization number according to the degrees of the even-level nodes, and otherwise, sending the calibration sequences at the same rule.
Specifically, during inter-stage and inter-cluster frequency domain scheduling, when the odd-stage nodes send calibration sequences to the even-stage nodes, the calibration sequences can be sent at different frequency points, the frequency point utilization number is determined according to the degree of the even-stage nodes, and otherwise, the calibration sequences are sent according to the same rule.
In the implementation, the time domain stage division is performed on the radio frequency units in the system according to the interference degree of the inter-stage transmitting and receiving calibration sequence, and the time domain stage division comprises the following steps:
in a network divided into n-level clusters, comparing from level 2, performing time domain stage division: and the kth-level node receives the calibration sequence, receives signal interference of nodes of the kth-3 level or the kth +3 level and the like, and if the signal-to-interference-and-noise ratio of the received useful signal is lower than a preset threshold, the cluster where the useful signal is located is enabled to perform antenna calibration again in the next time domain stage, otherwise, the calibration result is used as the final calibration result of the cluster where the useful signal is located.
Specifically, when the time domain stage division is performed on the radio frequency unit in the system according to the interference degree of the inter-stage transmission/reception calibration sequence, the time domain stage division may be performed in a network which can be divided into n-stage clusters, starting from the 2 nd stage for comparison: and the kth-level node receives the calibration sequence, receives signal interference of nodes of the kth-3 level or the kth +3 level and the like, and if the signal-to-interference-and-noise ratio of the received useful signal is lower than a preset threshold, the cluster where the useful signal is located is enabled to perform antenna calibration again in the next time domain stage, otherwise, the calibration result is used as the final calibration result of the cluster where the useful signal is located.
The following description is from the perspective of a radio frequency unit.
Fig. 2 is a schematic diagram of an implementation flow of a calibration sequence sending method, as shown in the figure, the method may include:
step 201, the radio frequency unit determines a calibration sequence to be sent and a radio frequency unit for receiving the calibration sequence, wherein each radio frequency unit is composed according to a DMIMO networking technology, each radio frequency unit is divided into at least two stages, the radio frequency unit of the same stage is clustered by taking the radio frequency unit of the previous stage as a central reference node, the radio frequency unit for receiving the calibration sequence is a central reference node, and a plurality of radio frequency units for sending the calibration sequence and a radio frequency unit for receiving the calibration sequence form a cluster;
step 202, the rf unit sends the calibration sequence to the rf unit that receives the calibration sequence.
The time-frequency resource scheduling scheme for antenna calibration under DMIMO proposed in the embodiment of the present invention may include two stages as follows, respectively, but this segmentation is an explanation for easy understanding, and does not mean that the technical scheme provided in the embodiment of the present invention must be divided into two stages or has another meaning:
1. grading/clustering radio frequency units according to a certain rule:
in practice, the radio frequency units are classified according to the geographic positions when being classified.
Specifically, in order to avoid the too large difference between the signal-to-noise ratios of the reference radio frequency unit and the calibration radio frequency unit, the radio frequency units may be classified according to geographical locations, and the radio frequency units of the same level are clustered by using the radio frequency unit of the previous level as a central reference node.
2. And performing time-frequency resource scheduling on the calibration sequence sent among the radio frequency units:
in implementation, the radio frequency units in the same cluster transmit the calibration sequence using the same frequency domain resources and/or time resources to the radio frequency units receiving the calibration sequence, which are different from other clusters and/or other hierarchical radio frequency units.
Specifically, the inter-stage and inter-cluster time-frequency domain scheduling is performed when the radio frequency unit sends and receives the calibration sequence, and the inter-stage and inter-cluster time-frequency domain scheduling includes that the inter-stage radio frequency unit simultaneously sends the calibration sequence to the connection node to reduce time complexity as much as possible, and frequency domain division is performed on the sending of the calibration sequence of the previous-stage reference node and the node in the same-stage cluster connected to the node in order to avoid interference caused when the sequence is sent to the same node. In addition, in order to ensure the accuracy of the inter-stage calibration, the radio frequency unit in the system is subjected to time domain division according to the interference degree of the inter-stage transmitting and receiving calibration sequence, so that the receiving calibration sequence is retransmitted.
Fig. 3 is a schematic flow chart of an implementation of determining a calibration factor, which may include:
step 301: all radio frequency units in the cooperation range are classified according to a certain rule, and clustering is carried out by adopting a strategy that a radio frequency unit at a level higher than that of a radio frequency unit at the same level is used as a central node.
Specifically, a central reference node in the cooperation range, also called a level 1 node, is determined, a cluster where the central reference node is located may be called a level 1 cluster, a radio frequency unit in the level 1 cluster is called a level 2 node, and further, with the level 2 node as a center, a node where the radio frequency unit is in the cluster and outside the level 1 cluster is called a level 3 node, and so on, the radio frequency units are divided, and a preset value of the cluster size may be adjusted according to available frequency domain resources.
Step 302: according to the division condition of the radio frequency units, performing time-frequency domain scheduling between stages and clusters, wherein the time-frequency domain scheduling comprises receiving and sending calibration sequences by the stage-separated radio frequency units in the same time slot and different frequency domains;
step 303: determining the range of the interstage radio frequency unit which needs to transmit and receive the calibration sequence again in the next time domain stage according to the interstage interference degree, and mainly considering the interference of the radio frequency units with similar levels;
step 304: each stage of radio frequency unit listed in the next time domain stage will utilize step 202 and step 203 to re-transmit and receive the antenna calibration sequence;
step 305: and after the scheduling method of the time-frequency domain resources of the transmitting and receiving calibration sequences of the radio frequency unit in the cooperation range is completed, calculating a calibration factor, and determining a final calibration factor according to the level of the radio frequency unit.
It can be seen from the above implementation that, in the case of applying the existing centralized antenna calibration technical scheme to the distributed large-scale antenna array, the calibration error may be too large, and in the existing distributed antenna calibration technical scheme, the time complexity is too high in the scenario where the number of radio frequency units is increased by adopting both the adjacent antenna calibration and the group calibration, the calibration sequence transmission scheme provided in the embodiment of the present invention can avoid the calibration error from being too large due to the position dispersion of the radio frequency unit arrays having the calibration relationship due to the antenna calibration time-frequency resource scheduling considering the calibration error, the radio frequency unit clustering and the step-by-step global calibration process, the calibration period can be shortened as much as possible by the step-by-step radio frequency units transmitting the calibration sequences simultaneously in the time domain stage, and the interference can be avoided by performing the frequency domain division on the radio frequency units transmitting the calibration sequences simultaneously, so that the time domain resources can be multiplexed as much as possible on the basis of reducing the calibration error, and realizing efficient scheduling of antenna calibration in a multi-node cooperation scene.
The following is an example.
In order to meet the strict requirements of the next generation mobile communication system, especially the 5G network, on high performance, with the development of the technology, the distributed massive multiple input multiple output (DMIMO) technology stands out in the numerous alternative key technologies of 5G with its advantages in improving the coverage, enhancing the edge user rate, and eliminating the indoor blind area, and fig. 4 is a schematic view of a DMIMO system scenario, such as the scenario shown in fig. 4. In practical scenarios, the antenna calibration technique for compensating the channel reciprocity loss is particularly important for a DMIMO system with multiple applications in TDD mode. In order to achieve efficient scheduling of antenna calibration while reducing calibration errors, the following will be described by way of example.
1. The system classifies all the radio frequency units in the cooperation range according to a certain rule, and adopts a strategy that the radio frequency unit at the upper stage of the radio frequency unit at the same stage is used as a central node for clustering.
In implementation, the highest level of radio frequency unit is the radio frequency unit in the cluster containing the highest number of radio frequency units in each cluster. Specifically, the criteria for selecting the central node may further include: the center of a radio frequency unit distribution area is taken as a circle center, a certain threshold value is taken as a radius to be used as a cluster, the radio frequency units in the cluster are taken as the center to be used as the cluster, and each cluster comprises the radio frequency units with higher number and is taken as the level 1 node in the cooperation range.
In the example, a plurality of radio frequency units under the same baseband processing unit are distributed and placed in a certain area, the center of the area is taken as the center of a circle, a certain preset value is taken as a radius to serve as a cluster, the radio frequency units contained in the cluster are taken as candidate nodes of a center node, then the candidate nodes are taken as the center of a circle, the same preset value is taken as a radius to serve as a cluster, the cluster contains a central reference node which is large in the number of radio frequency units and is to be in a cooperation range, the central reference node is also called a level 1 node, and the cluster where the radio frequency units are located can be called a level 1 cluster. The radio frequency unit located in the level 1 cluster is closest to the central reference node, and the calibration error is lowest, so that the more the number of the radio frequency units is, the smaller the total error in the system is, and in addition, the central node is basically located in the center of the cooperation area, and the later process is favorable for shortening the calibration period of the whole system.
After the level 1 node and the level 1 cluster are determined, the radio frequency unit in the level 1 cluster is called a level 2 node, the level 2 node is further taken as a center, the same preset value is taken as a radius to serve as a cluster, the node of the radio frequency unit in the cluster and outside the level 1 cluster is called a level 3 node, and the like, so that the radio frequency unit in the cooperation range is divided into n levels.
In implementation, the preset value of cluster radius of the clusters is adjusted according to the number of frequency domain resources. Specifically, the preset value of the cluster radius can be adjusted according to the number of available frequency domain resources.
2. According to the division condition of the radio frequency units, the calibration sequences are transmitted and received by the stages in the same time slot, fig. 5 is a schematic diagram of the transmission and reception of the calibration sequences in the time domain stage, and as shown in fig. 5, the 1 st time slot, the 1 st stage node and the 3 rd stage node transmit the calibration sequences, and the 2 nd stage node and the 4 th stage node receive the calibration sequences; and in the 2 nd time slot, the 1 st level node and the 3 rd level node receive the calibration sequence, and the 2 nd level node and the 4 th level node transmit the calibration sequence, otherwise, the same is carried out, namely the 4 th level calibration sequence is received and transmitted in two time slots. Since mutual interference may be caused when the kth-level node and the (k + 2) -level node transmit the calibration sequence to the (k + 1) -level node, the kth-level node and the (k + 2) -level node that transmit the calibration sequence to the same (k + 1) -level node may transmit the calibration sequence in different frequency domains.
3. And determining the cluster radius of the cluster according to the interference degree of the inter-stage transmitting and receiving calibration sequence.
Specifically, the range of the radio frequency unit for re-performing the transmit/receive calibration sequence may be determined according to the interference degree of the inter-stage transmit/receive calibration sequence, so as to perform time domain stage division on the radio frequency unit in the system.
In the example, the inter-stage interference degree is determined by measuring the signal-to-interference-and-noise ratio of the channel between the radio frequency units. The kth level node performs antenna calibration by using the calibration sequences sent by the kth-1 level node and the kth +1 level node as useful signals, but receives interference from the kth-3 level node or the kth +3 level node. The calibration sequences sent by the (k-1) level node and the (k + 1) level node are in different frequency domains, and when the (k-3) level node or the (k + 3) level node sends the calibration sequences in the two frequency domains, a certain degree of interference can be caused. If the signal to interference plus noise ratio of the useful signal is higher than the preset value in the frequency domain where the k-th node receives the useful signal, it indicates that the k-3-th node or the k + 3-th node does not interfere with the signal received by the k-th node, i.e. the calibration result in the time domain phase can be used as the final calibration result of the cluster where the useful signal is located, otherwise, if the signal to interference plus noise ratio of the useful signal is higher than the preset value, i.e. it indicates that the k-3-th node or the k + 3-th node can interfere with the signal received by the k-th node, it makes the cluster where the useful signal is located re-perform antenna calibration in the next time domain phase, fig. 6 is a time domain phase division schematic diagram, as shown in fig. 6, in the first time domain phase, the 5-th node and the 3-th node transmit the calibration sequence in the same frequency domain, and the signal to interference plus noise ratio of the 5-th node received by the 6-th node is lower than the preset value, then the level 5 cluster re-performs antenna calibration in the second time domain phase.
4. And each stage of radio frequency unit listed in the next time domain stage utilizes the time-frequency domain scheduling schemes 1 and 2 to perform the sending of the antenna calibration sequence again.
5. And after the transmitting and receiving calibration sequences of the radio frequency unit in the cooperation range are completed, calculating the calibration factor. The calibration factor of the radio frequency unit is related to its class, i.e. the calibration factor of the radio frequency unit is the product of the intra-cluster calibration factor and the factor obtained by the previous-stage cluster calibration of the cluster center node.
Based on the same inventive concept, the embodiment of the present invention further provides a radio frequency unit, a calibration sequence transmitting apparatus, and a computer-readable storage medium, and because the principle of solving the problem of these devices is similar to that of the calibration sequence transmitting method, the implementation of these devices may refer to the implementation of the method, and repeated details are not repeated.
When the technical scheme provided by the embodiment of the invention is implemented, the implementation can be carried out as follows.
Fig. 7 is a time-frequency resource scheduling system for antenna calibration under DMIMO, which includes:
a hierarchical clustering module 701, configured to rank a plurality of radio frequency units in a cooperation range according to a predetermined rule, where a radio frequency unit at a peer is clustered by using a radio frequency unit at an upper level as a central node;
a scheduling module 702, configured to send and receive a calibration sequence by an inter-stage and inter-cluster time-frequency domain scheduling manner according to a division condition of a radio frequency unit in a cooperation range;
a re-dividing module 703, configured to determine, according to the interference degree of the inter-stage transmission/reception calibration sequence, a radio frequency unit range for re-transmitting/receiving the calibration sequence, perform time domain stage division on calibration of a radio frequency unit in a cooperation range, and perform transmission/reception of the calibration sequence in a set time domain stage in the inter-stage and inter-cluster time-frequency domain scheduling manner;
a calibration factor calculation module 704, configured to calculate a final calibration factor according to the radio frequency unit level.
In an implementation, the hierarchical clustering module is further configured to rank a plurality of radio frequency units within the cooperation range according to a predetermined rule in the following manner:
determining a central node in a cooperation range, taking the central node as a level 1 node, and taking the level 1 node as a center to serve as a cluster, so as to obtain a level 1 cluster;
taking nodes in the cluster except the central node as a level 2 node, taking the level 2 node as the center and the cluster outside the level 1 cluster to obtain a level 2 cluster;
taking the nodes in the cluster except the central node as the 3 rd level nodes, and so on, taking the nth level node as the center and the cluster outside the nth-1 level cluster as the nth level cluster, and taking the nodes in the cluster except the central node as the n +1 level nodes.
In an implementation, the hierarchical clustering module is further configured to determine the level 1 node as follows:
the center of a radio frequency unit distribution area is used as a circle center, a preset threshold value is used as a radius to serve as a cluster, radio frequency units in the cluster are used as the center to serve as the cluster, and each cluster comprises the radio frequency units with the higher number and serves as a level 1 node in a cooperation range.
In an implementation, the calibration factor calculation module is further configured to determine the final calibration factor as follows:
and performing antenna calibration in the cluster by taking the cluster center node as a reference radio frequency unit, wherein the cluster calibration factor is the product of the cluster calibration factor and the factor obtained by the previous-stage cluster calibration of the cluster center node.
In an implementation, the scheduling module is further configured to perform inter-stage and inter-cluster time domain scheduling in the following manner:
the stages transmit and receive calibration sequences in the same time slot.
In an implementation, the scheduling module is further configured to perform inter-stage and inter-cluster frequency domain scheduling in the following manner:
and when the odd-level nodes send the calibration sequences to the even-level nodes, sending the calibration sequences at different frequency points, determining the frequency point utilization number according to the degrees of the even-level nodes, and otherwise, sending the calibration sequences at the same rule.
In an implementation, the re-partition module is further configured to perform time domain stage partition on the radio frequency units in the system according to the interference degree of the inter-stage transmission/reception calibration sequence in the following manner:
in a network divided into n-level clusters, comparing from level 2, performing time domain stage division: and the kth-level node receives the calibration sequence, receives signal interference of nodes of the kth-3 level or the kth +3 level and the like, and if the signal-to-interference-and-noise ratio of the received useful signal is lower than a preset threshold, the cluster where the useful signal is located is enabled to perform antenna calibration again in the next time domain stage, otherwise, the calibration result is used as the final calibration result of the cluster where the useful signal is located.
Fig. 8 is a schematic structural diagram of a radio frequency unit, as shown in the figure, the radio frequency unit includes:
the processor 800, which is used to read the program in the memory 820, executes the following processes:
determining a calibration sequence to be sent and radio frequency units for receiving the calibration sequence, wherein each radio frequency unit is formed according to a DMIMO networking technology and is divided into at least two stages, the radio frequency units of the same stage are clustered by taking the radio frequency unit of the previous stage as a central reference node, the radio frequency unit for receiving the calibration sequence is a central reference node, and a plurality of radio frequency units for sending the calibration sequence and one radio frequency unit for receiving the calibration sequence form a cluster;
transmitting a calibration sequence to a radio frequency unit receiving the calibration sequence;
a transceiver 810 for receiving and transmitting data under the control of the processor 800.
In practice, the radio frequency units are classified according to the geographic positions when being classified.
In implementation, the radio frequency units in the same cluster transmit the calibration sequence using the same frequency domain resources and/or time resources to the radio frequency units receiving the calibration sequence, which are different from other clusters and/or other hierarchical radio frequency units.
In implementation, the preset value of cluster radius of the clusters is adjusted according to the number of frequency domain resources.
In an implementation, the method further comprises the following steps:
and determining the cluster radius of the cluster according to the interference degree of the inter-stage transmitting and receiving calibration sequence.
In implementation, the highest level of radio frequency unit is the radio frequency unit in the cluster containing the highest number of radio frequency units in each cluster.
Where in fig. 8, the bus architecture may include any number of interconnected buses and bridges, with various circuits being linked together, particularly one or more processors represented by processor 800 and memory represented by memory 820. 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 810 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. The processor 800 is responsible for managing the bus architecture and general processing, and the memory 820 may store data used by the processor 800 in performing operations.
Fig. 9 is a schematic structural diagram of a calibration sequence transmitting apparatus, which may include:
a determining module 901, configured to determine a calibration sequence to be sent and radio frequency units that receive the calibration sequence, where each radio frequency unit is formed according to a DMIMO networking technology, each radio frequency unit is divided into at least two stages, a peer radio frequency unit is clustered by using a previous radio frequency unit as a central reference node, a radio frequency unit that receives the calibration sequence is a central reference node, and a plurality of radio frequency units that send the calibration sequence and a radio frequency unit that receives the calibration sequence form a cluster;
a sending module 902, configured to send the calibration sequence to the radio frequency unit that receives the calibration sequence.
In practice, the radio frequency units are classified according to the geographic positions when being classified.
In an implementation, the sending module is further configured to use the same frequency domain resource and/or the same time resource when the radio frequency unit in the same cluster sends the calibration sequence to the radio frequency unit that receives the calibration sequence, and the frequency domain resource and/or the time resource are different from the radio frequency units in other clusters and/or other hierarchies.
In implementation, the preset value of cluster radius of the clusters is adjusted according to the number of frequency domain resources.
In an implementation, the method further comprises the following steps:
and determining the cluster radius of the cluster according to the interference degree of the inter-stage transmitting and receiving calibration sequence.
In implementation, the highest level of radio frequency unit is the radio frequency unit in the cluster containing the highest number of radio frequency units in each cluster.
For convenience of description, each part of the above-described apparatus is separately described as being functionally divided into various modules or units. Of course, the functionality of the various modules or units may be implemented in the same one or more pieces of software or hardware in practicing the invention.
A computer-readable storage medium, characterized in that the computer-readable storage medium stores a computer program for executing the above-described calibration sequence transmission method.
The specific implementation can refer to the implementation of the calibration sequence transmission method.
For convenience of description, each part of the above-described apparatus is separately described as being functionally divided into various modules or units. Of course, the functionality of the various modules or units may be implemented in the same one or more pieces of software or hardware in practicing the invention.
In summary, in the technical solution provided in the embodiment of the present invention, all radio frequency units in the cooperation range are classified according to a certain rule, and the radio frequency units of the same level are clustered by using the radio frequency unit of the previous level as a central node; the radio frequency unit in the system transmits and receives the calibration sequence by an inter-stage and inter-cluster time-frequency domain scheduling method according to the division condition; determining the range of the radio frequency unit for retransmitting and receiving the calibration sequence according to the interference degree of the interstage sending and receiving calibration sequence, thereby dividing the time domain stage of the calibration of the radio frequency unit in the system, and sending and receiving the calibration sequence in the set time domain stage by the interstage and inter-cluster time-frequency domain scheduling scheme; a final calibration factor is calculated from the radio unit level.
Further, the radio frequency unit classification according to a certain standard may further include: finding a central node in the cooperation range, wherein the central node is a level 1 node, the level 1 node is taken as a center and is called a level 1 cluster, nodes in the cluster (except the center) are level 2 nodes, the cluster which is taken as the center and is outside the level 1 cluster is called a level 2 cluster, the nodes in the cluster (except the center) are called level 3 nodes, and so on, the cluster which is taken as the center and is outside the n-1 cluster is called a level n cluster, and the nodes in the cluster (except the center) are called level n +1 nodes.
Further, the criteria for selecting the central node may further include: the center of a radio frequency unit distribution area is taken as a circle center, a certain threshold value is taken as a radius to be used as a cluster, the radio frequency units in the cluster are taken as the center to be used as the cluster, and each cluster comprises the radio frequency units with higher number and is taken as the level 1 node in the cooperation range. That is, the radio frequency unit at the highest level is the radio frequency unit in the cluster containing the highest number of radio frequency units in each cluster.
Further, the cluster center node is used as a reference radio frequency unit in the cluster for antenna calibration, and the calibration factor of the cluster is related to the level of the cluster, namely the cluster calibration factor is the product of the cluster calibration factor and the factor obtained by previous-level cluster calibration of the cluster center node.
Further, the inter-stage and inter-cluster time domain scheduling schemes may include: the stages transmit and receive calibration sequences in the same time slot.
Further, the inter-stage and inter-cluster frequency domain scheduling schemes may include: and when the odd-level nodes send the calibration sequences to the even-level nodes, sending the calibration sequences at different frequency points, determining the frequency point utilization number according to the degrees of the even-level nodes, and otherwise, sending the calibration sequences at the same rule.
Further, the time domain phase division is performed on the radio frequency units in the system according to the interference degree of the inter-stage transmission and reception calibration sequence, and may include: in a network that can be divided into n-level clusters, time domain phase division is performed starting from level 2: and the kth-level node receives the calibration sequence, receives signal interference of nodes of the kth-3 level or the kth +3 level and the like, and if the signal-to-interference-and-noise ratio of the received useful signal is lower than a preset threshold, the cluster where the useful signal is located is enabled to perform antenna calibration again in the next time domain stage, otherwise, the calibration result is used as the final calibration result of the cluster where the useful signal is located.
As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention 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 invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program 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 computer program instructions may also be stored in a computer-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 computer-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 computer program 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 invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims (10)

1. A time-frequency resource scheduling method for antenna calibration under DMIMO is characterized by comprising the following steps:
classifying a plurality of radio frequency units in a cooperation range according to a preset rule, and clustering by taking the radio frequency unit at the upper stage of the radio frequency unit at the same stage as a central node;
the radio frequency unit in the cooperation range transmits and receives the calibration sequence in an inter-stage and inter-cluster time-frequency domain scheduling mode according to the division condition of the radio frequency unit;
determining the range of the radio frequency unit for retransmitting and receiving the calibration sequence according to the interference degree of the interstage sending and receiving calibration sequence, dividing the time domain stage of the calibration of the radio frequency unit in the cooperation range, and sending and receiving the calibration sequence in a set time domain stage in the interstage and inter-cluster time-frequency domain scheduling mode;
a final calibration factor is calculated from the radio unit level.
2. The method of claim 1, wherein the ranking the plurality of radio frequency units in the cooperation area according to a predetermined rule comprises:
determining a central node in a cooperation range, taking the central node as a level 1 node, and taking the level 1 node as a center to serve as a cluster, so as to obtain a level 1 cluster;
taking nodes in the cluster except the central node as a level 2 node, taking the level 2 node as the center and the cluster outside the level 1 cluster to obtain a level 2 cluster;
taking the nodes in the cluster except the central node as the 3 rd level nodes, and so on, taking the nth level node as the center and the cluster outside the nth-1 level cluster as the nth level cluster, and taking the nodes in the cluster except the central node as the n +1 level nodes.
3. A method according to claim 1 or 2, characterized in that the level 1 node is determined as follows:
the center of a radio frequency unit distribution area is used as a circle center, a preset threshold value is used as a radius to serve as a cluster, radio frequency units in the cluster are used as the center to serve as the cluster, and each cluster comprises the radio frequency units with the higher number and serves as a level 1 node in a cooperation range.
4. The method of claim 1, wherein the final calibration factor is determined as follows:
and performing antenna calibration in the cluster by taking the cluster center node as a reference radio frequency unit, wherein the cluster calibration factor is the product of the cluster calibration factor and the factor obtained by the previous-stage cluster calibration of the cluster center node.
5. A time-frequency resource scheduling system for antenna calibration under DMIMO is characterized by comprising:
the hierarchical clustering module is used for classifying a plurality of radio frequency units in the cooperation range according to a preset rule, and clustering by taking the radio frequency unit at the upper level of the radio frequency unit at the same level as a central node;
the scheduling module is used for transmitting and receiving the calibration sequence by the radio frequency unit in the cooperation range in an inter-stage and inter-cluster time-frequency domain scheduling mode according to the division condition of the radio frequency unit;
the re-dividing module is used for determining the range of the radio frequency unit for re-sending and receiving the calibration sequence according to the interference degree of the inter-stage sending and receiving calibration sequence, dividing the calibration of the radio frequency unit in the cooperation range in a time domain stage, and sending and receiving the calibration sequence in a set time domain stage in the inter-stage and cluster time-frequency domain scheduling mode;
and the calibration factor calculation module is used for calculating a final calibration factor according to the radio frequency unit level.
6. A method for transmitting a calibration sequence, comprising:
the radio frequency unit determines a calibration sequence to be sent and receives the radio frequency units of the calibration sequence, wherein each radio frequency unit is composed according to a distributed multi-input multi-output DMIMO networking technology, each radio frequency unit is divided into at least two stages, the radio frequency units of the same stage are clustered by taking the radio frequency unit of the previous stage as a central reference node, the radio frequency unit for receiving the calibration sequence is the central reference node, and a plurality of radio frequency units for sending the calibration sequence and one radio frequency unit for receiving the calibration sequence form a cluster;
the radio unit transmits the calibration sequence to the radio unit that receives the calibration sequence.
7. The method of claim 6, wherein the radio units in the same cluster transmit calibration sequences using the same frequency domain resources and/or time resources to the radio units receiving the calibration sequences, which are different from other clusters and/or other hierarchical radio units.
8. A radio frequency unit, comprising:
a processor for reading the program in the memory, performing the following processes:
determining a calibration sequence to be sent and radio frequency units for receiving the calibration sequence, wherein each radio frequency unit is formed according to a DMIMO networking technology and is divided into at least two stages, the radio frequency units of the same stage are clustered by taking the radio frequency unit of the previous stage as a central reference node, the radio frequency unit for receiving the calibration sequence is a central reference node, and a plurality of radio frequency units for sending the calibration sequence and one radio frequency unit for receiving the calibration sequence form a cluster;
transmitting a calibration sequence to a radio frequency unit receiving the calibration sequence;
a transceiver for receiving and transmitting data under the control of the processor.
9. A calibration sequence transmitting apparatus, comprising:
the device comprises a determining module, a receiving module and a transmitting module, wherein the determining module is used for determining a calibration sequence to be transmitted and radio frequency units for receiving the calibration sequence, each radio frequency unit is formed according to a DMIMO networking technology and is divided into at least two stages, the radio frequency unit at the same stage is clustered by taking the radio frequency unit at the upper stage as a central reference node, the radio frequency unit for receiving the calibration sequence is the central reference node, and a plurality of radio frequency units for transmitting the calibration sequence and one radio frequency unit for receiving the calibration sequence form a cluster;
and the sending module is used for sending the calibration sequence to the radio frequency unit receiving the calibration sequence.
10. A computer-readable storage medium having stored thereon a computer program for executing the method of any one of claims 1 to 4, or 6 to 7.
CN202010640384.9A 2020-07-06 2020-07-06 Method and equipment for scheduling antenna calibration time-frequency resources under distributed multi-input multi-output Pending CN113904738A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CN202010640384.9A CN113904738A (en) 2020-07-06 2020-07-06 Method and equipment for scheduling antenna calibration time-frequency resources under distributed multi-input multi-output
PCT/CN2020/134479 WO2022007324A1 (en) 2020-07-06 2020-12-08 Distributed multiple input multiple output antenna calibration time frequency resource scheduling method and device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010640384.9A CN113904738A (en) 2020-07-06 2020-07-06 Method and equipment for scheduling antenna calibration time-frequency resources under distributed multi-input multi-output

Publications (1)

Publication Number Publication Date
CN113904738A true CN113904738A (en) 2022-01-07

Family

ID=79186692

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010640384.9A Pending CN113904738A (en) 2020-07-06 2020-07-06 Method and equipment for scheduling antenna calibration time-frequency resources under distributed multi-input multi-output

Country Status (2)

Country Link
CN (1) CN113904738A (en)
WO (1) WO2022007324A1 (en)

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10230436B2 (en) * 2014-10-20 2019-03-12 RF DSP Inc. Methods for channel information acquisition, signal detection and transmission in multi-user wireless communication systems
CN110178315B (en) * 2017-01-24 2020-10-23 华为技术有限公司 Antenna correction method and device
US10820332B2 (en) * 2017-03-11 2020-10-27 Qualcomm Incorporated Sounding scheduling for distributed MIMO communication in an access point cluster
US10972158B2 (en) * 2017-03-16 2021-04-06 Samsung Electronics Co., Ltd. Distributed FD-MIMO: cellular evolution for 5G and beyond
EP3632002B1 (en) * 2017-06-19 2021-08-04 Telefonaktiebolaget LM Ericsson (PUBL) Method and apparatus for antenna calibration in a wireless communication system
US11133875B2 (en) * 2017-10-20 2021-09-28 Telefonaktiebolaget Lm Ericsson (Publ) Over-the-air reciprocity calibration for distributed-multiple input—multiple output systems
CN108155958A (en) * 2017-11-22 2018-06-12 西南电子技术研究所（中国电子科技集团公司第十研究所） Extensive mimo antenna array far field calibration system
CN109842520B (en) * 2018-12-27 2021-06-22 华为技术有限公司 Method, device and system for determining network topology

Also Published As

Publication number Publication date
WO2022007324A1 (en) 2022-01-13

Similar Documents

Publication Publication Date Title
US11743882B2 (en) Apparatus and method for transmitting and receiving beam information in wireless communication system
JP5241380B2 (en) Data processing method and apparatus in multi-input multi-output system
CN105991271B (en) Apparatus, method and storage medium for wireless communication
US8913972B2 (en) Antenna clustering for multi-antenna aperture selection
CN104662813A (en) Interference measurement method and apparatus for use in distributed antenna system
US11218192B2 (en) Uplink active set management for multiple-input multiple-output communications
CN102571177A (en) Wireless base station device, terminal, and wireless communication method
US20100227566A1 (en) Communication system and method of performing interference control using random beamforming technique
US10925063B2 (en) User selection method for non-orthogonal multiple access system and base station thereof
CN101156335B (en) Wireless base station apparatus
US11032841B2 (en) Downlink active set management for multiple-input multiple-output communications
CN101908915B (en) Signal transmission method, device and base station
KR102503794B1 (en) Transmission power allocation method based on user clustering and reinforcement learning
WO2018228697A1 (en) Beam selection
US8374554B2 (en) Communication system for adjusting mode of collecting interference channel information
CN113904738A (en) Method and equipment for scheduling antenna calibration time-frequency resources under distributed multi-input multi-output
KR20130104369A (en) Method for determining transmitting power in the mimo system based on cooperative transmitting
US20220150903A1 (en) Method and apparatus for transmitting and receiving signal for cooperative transmission in communication system
US11677452B2 (en) Method and apparatus for transmitting and receiving signal for terminal-centric cooperative transmission
CN111953463A (en) Pilot frequency distribution method based on user clustering
CN111953392B (en) Antenna calibration sequence sending method and system for distributed MIMO
WO2023272598A1 (en) Reference signal configuration method and apparatus, and device and storage medium
TWI834162B (en) Signal transmission method, device, terminal and base station
CN102404030B (en) Method, device and system for determining target forming weight vector
CN103477686B (en) Including the power distribution in the wireless system with the base station with aerial array

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination