WO2017185994A1

WO2017185994A1 - Clustering method, device and system

Info

Publication number: WO2017185994A1
Application number: PCT/CN2017/080415
Authority: WO
Inventors: 张瑜; 王欣晖; 汪彬; 李红豆; 常永宇
Original assignee: 中兴通讯股份有限公司
Priority date: 2016-04-27
Filing date: 2017-04-13
Publication date: 2017-11-02
Also published as: CN107333271A

Abstract

Provided in the present invention are a clustering method, device and system. The method comprises: a centralized processing unit receiving an RSRP list reported by a terminal through a base station, wherein the RSRP list records RSRPs of all base stations covered and measured by the terminal; the centralized processing unit determining, according to the RSRP list, terminal-centric initial clusters; and the centralized processing unit determining, according to a preset mode and within final clusters, a base station using JT and serving the terminal and a base station using CB and serving the terminal. The present invention solves a problem in the related art in which interference occurs between densely deployed base stations in a C-RAN network.

Description

Clustering method, device and system

Technical field

The present invention relates to the field of communications, and in particular to a method, apparatus and system for clustering.

Background technique

In recent years, with the explosive growth of intelligent terminals, the network traffic has risen sharply, and the mobile service data traffic has grown rapidly, which has brought increasingly fierce competitive pressure to operators. It has been difficult to improve network utilization from air interface design and frequency band resources. To achieve breakthroughs, operators must implement reforms and upgrades that involve the entire network system architecture. In the traditional radio access network (Radio Access Network, RAN for short), as the number of base stations increases, the construction and maintenance costs of a large number of base stations will also increase significantly, and limited information exchange between base stations. It makes it difficult to achieve resource sharing between base stations, which makes the actual utilization efficiency of network hardware resources very low.

Based on the above background, C-RAN is born. C-RAN is a green wireless access network based on Centralized Processing, Collaborative Radio and Real-time Cloud Infrastructure. Structure (Clean System). The C-RAN architecture consists of three parts: a centralized virtualized baseband unit pool (BBU pool), and a distributed wireless cooperative network consisting of radio remote units (RRUs). And a fiber optic transmission network between the two, which has limited capacity in the actual architecture. The centralized virtual baseband resource processing pool uses virtualization technology to abstract physical baseband units located in different geographical locations into a baseband resource processing pool, which can ensure low-latency and high-efficiency information exchange between different baseband processing units, and is powerful at the same time. The processing power and computing functions make this CoMP transmission technology have a very good performance under the C-RAN architecture.

The CoMP transmission technology includes joint transmission (JT) and Coordinated Beamforming (CB). For a certain user, the JT mode is that multiple base stations share channel state information (CSI) between the user and multiple base stations, and cooperate with the beam for the user. The user data is transmitted and transmitted. The CB mode is that multiple base stations share CSI between the user and multiple base stations. At the same time, only one base station transmits user data for the user, and other base stations circumvent the spatial beam of the user direction. The traditional Coordinated Multiple Points Transmission/Reception (CoMP) method uses one of the two. For the C-RAN architecture, only the JT method will cause the transmission network to be overloaded, but only Using the CB method will result in waste of resources. In view of the above problems in the related art, there is currently no effective solution.

Summary of the invention

The embodiments of the present invention provide a clustering method, device, and system, to at least solve the problem of interference between related base stations in a densely deployed base station in a C-RAN network.

According to an aspect of the present invention, a method for clustering is provided, which includes: a centralized processing unit receives a reference signal receiving power (Reference Signal Receiving Power, RSRP for short) list reported by a terminal, where the RSRP The list is used to record that the terminal measures the RSRP of all the base stations that cover the terminal; the centralized processing unit determines an initial clustering centered on the terminal according to the RSRP list; and the centralized processing unit determines according to a preset manner. The final clustering, wherein the base station in the final clustering comprises: a base station that uses the joint transmission JT mode and serves the terminal, and a base station that uses the cooperative beam-weighted CB mode and serves the terminal.

Optionally, the centralized processing unit determines, according to the RSRP list, that the initial clustering centered on the terminal includes: the centralized processing unit determines whether there is a first RSRP that meets a preset condition in the RSRP list; When the first RSRP exists in the RSRP list, the centralized processing unit determines a first base station corresponding to the RSRP; and the centralized processing unit adds the first base station to the initial cluster.

Optionally, the preset condition is:

RSRP _max -RSRP _CoMP ≤RSRP _threshold

The RSRP _max is a maximum value in the RSRP list corresponding to the terminal, and the RSRP _CoMP is a value corresponding to the base station that joins the initial clustering in the RSRP list, and the RSRP _threshold is a preset fixed threshold.

Optionally, the centralized processing unit determines, according to a preset manner, a base station that uses the JT mode in the final cluster and serves the terminal, and the base station that uses the CB mode and serves the terminal includes: the centralized processing unit passes Dichotomy, under the constraint of transmission network capacity and transmission power limitation, to maximize the terminal rate as an optimization target, determine the base station using the JT mode and serving the terminal in the initial clustering, and use the CB mode And a base station serving the terminal; the centralized processing unit uses an exhaustive method, and determines a base station in the final cluster that uses the JT mode in the transmission mode and serves the terminal, and maximizes the terminal rate as an optimization target, and A base station that uses the CB mode in the transmission mode and serves the terminal.

Optionally, the base station that satisfies the following conditions is a base station that uses the JT mode:

0≤RSRP _max -RSRP _JT ≤RSRP _threshold -δ

A base station that satisfies the following conditions is a base station that uses the CB mode:

RSRP _threshold -δ≤RSRP _max -RSRP _CB ≤RSRP _threshold

Wherein, the RSRP _max is a maximum value in the RSRP list corresponding to the terminal, and the RSRP _JT is a value in the RSRP list corresponding to the base station that uses the JT method that satisfies the formula condition, and the RSRP _CB uses the CB to satisfy the formula condition. The value of the RSRP _threshold in the RSRP list corresponding to the base station of the mode is a preset fixed threshold; 0≤δ≤RSRP _threshold is a variable, wherein the change of the variable causes the terminal and the base station serving the terminal The change in correspondence between the two to change the rate of the terminal.

Optionally, the optimization goal of maximizing the terminal rate is determined by:

Where K is the total number of terminals, and β _j is the scheduling priority weight of terminal _j ;

The constraints are determined by:

Where d _ij and w _ij are the i-th row and j-th column elements in the JT matrix and the precoding matrix, respectively; R _j is the terminal rate of the jth terminal; P _i and C _i are the maximum transmission power of the base station B _i , respectively And the transmission capacity between the base station and the centralized processing unit.

Optionally, the method further includes: the centralized processing unit allocates bandwidth to the base station according to the determined transmission manner used by the base station in the final cluster and the carried terminal data, where the transmission manner includes a JT mode and CB way.

Optionally, the method further includes: the centralized processing unit receiving precoding determined by the base station according to the received training sequence, where the precoding is used to indicate a base station that uses the JT mode and serves the terminal A spatial wave speed for transmitting the directivity and carrying data for the terminal, and a base station serving the terminal using the CB mode to circumvent the spatial beam in the direction of the terminal.

According to another aspect of the present invention, a method for clustering is provided, comprising: receiving, by a base station, an RSRP list reported by a terminal, where the RSRP list is used to record, by the terminal, an RSRP of all base stations covering the terminal; The base station sends the RSRP list to a centralized processing unit.

Optionally, the method further includes: the base station receiving a training sequence reported by the terminal; the base station determining channel state information according to the training sequence, and determining to obtain precoding according to the channel state information.

According to another aspect of the present invention, a device for clustering is provided, which is applied to a centralized processing unit side, and includes: a first receiving module, configured to receive an RSRP list reported by a terminal through a base station, where the RSRP list The first determining module is configured to determine an initial clustering centered on the terminal according to the RSRP list; and the second determining module is configured to be based on the pre-measurement The mode determines a base station in the final cluster that uses the JT mode and serves the terminal, and a base station that uses the CB mode and serves the terminal.

According to still another aspect of the embodiments of the present invention, a clustering apparatus is provided, which is applied to a base station side, and includes: a second receiving module, configured to receive an RSRP list reported by a terminal, where the RSRP list is used for a recording station. The terminal measures the RSRP of all base stations covering the terminal; the sending module is configured to send the RSRP list to the centralized processing unit.

According to still another aspect of the present invention, there is provided a clustered system comprising: the above-described means applied to the centralized processing unit side and the above-described means applied to the base station side.

According to still another embodiment of the present invention, a storage medium is also provided. The storage medium is arranged to store program code for performing the following steps:

The centralized processing unit receives a reference signal received power RSRP list reported by the terminal by the base station, where the RSRP list is used to record that the terminal measures an RSRP of all base stations covering the terminal; the centralized processing unit determines according to the RSRP list. An initial clustering centered on the terminal; the centralized processing unit determines a final cluster according to a preset manner, where the base station in the final cluster includes: a base station that uses the joint transmission JT mode and serves the terminal And a base station that uses the cooperative beam-enhancing CB mode and serves the terminal.

The base station receives the RSRP list reported by the terminal, where the RSRP list is used to record the RSRP of all the base stations that the terminal measures the coverage terminal; the base station sends the RSRP list to the centralized processing unit; the base station receives the training sequence reported by the terminal; and the base station determines the channel state information according to the training sequence. And determining the precoding according to the channel state information.

According to the embodiment of the present invention, the centralized processing unit receives the RSRP list reported by the terminal through the base station, and determines the initial clustering centered on the terminal according to the RSRP list, and then determines, according to the preset manner, that the JT mode is used in the final clustering and serves the terminal. A base station, and a base station that uses the CB mode and serves the terminal, that is, the base station is divided into a base station using the JT mode and the CB mode, so that the base station can simultaneously maximize the use frequency band in the case of network system resources such as transmission network capacity and transmission power being limited. Thereby, the problem of interference between base stations densely deployed in the C-RAN network in the related art is solved.

DRAWINGS

The drawings described herein are intended to provide a further understanding of the invention, and are intended to be a part of the invention. In the drawing:

1 is a flow chart 1 of a method for clustering according to an embodiment of the present invention;

2 is a second flowchart of a method for clustering according to an embodiment of the present invention;

3 is a structural block diagram 1 of a device for clustering according to an embodiment of the present invention;

4 is a structural block diagram 2 of a device for clustering according to an embodiment of the present invention;

FIG. 5 is a structural block diagram of a system for clustering according to an embodiment of the present invention; FIG.

6 is a schematic diagram of a system model in accordance with an embodiment of the present invention.

Detailed ways

The invention will be described in detail below with reference to the drawings in conjunction with the embodiments. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict.

It is to be understood that the terms "first", "second" and the like in the specification and claims of the present invention are used to distinguish similar objects, and are not necessarily used to describe a particular order or order.

Example 1

The present invention provides a method for clustering. FIG. 1 is a flowchart 1 of a method for clustering according to an embodiment of the present invention. As shown in FIG. 1, the steps of the method include:

Step S102: The central processing unit receives the RSRP list reported by the terminal through the base station, where the RSRP list is used to record the RSRP of all the base stations of the terminal that measure the coverage terminal;

Step S104: The centralized processing unit determines the initial clustering centered on the terminal according to the RSRP list;

Step S106: The centralized processing unit determines the final clustering according to a preset manner, where the base station in the final clustering comprises: a base station that uses the joint transmission JT mode and serves the terminal, And a base station that uses the cooperative beam-enhancing CB mode and serves the terminal.

Through the foregoing steps S102 to S106 of the embodiment, the centralized processing unit receives the RSRP list reported by the terminal through the base station, and determines the initial clustering centered on the terminal according to the RSRP list, and then determines the JT used in the final cluster according to a preset manner. A base station that serves the terminal and a base station that uses the CB mode and serves the terminal, that is, the base station is divided into a base station that uses the JT mode and uses the CB mode, so that the base station can simultaneously have limited network network resources such as transmission network capacity and transmission power. In this case, the frequency band is maximized, thereby solving the problem of interference between base stations densely deployed in the C-RAN network in the related art.

It should be noted that the centralized processing unit involved in this embodiment is a baseband centralized processing pool in the C-RAN, and belongs to the centralized controller part.

In an optional implementation manner of this embodiment, the centralized processing unit involved in the step S104 in this embodiment determines the terminal-centered initial clustering according to the RSRP list. In an optional implementation manner of this embodiment, It is achieved as follows:

Step S104-1: The intermediate processing unit determines whether there is a first RSRP that satisfies the preset condition in the RSRP list;

The preset condition is optional in this embodiment:

RSRP _max -RSRP _CoMP ≤RSRP _threshold

The RSRP _max is the maximum value in the RSRP list corresponding to the terminal, and the RSRP _CoMP is the value corresponding to the base station added to the initial cluster in the RSRP list, and the RSRP _threshold is a preset fixed threshold.

Step S104-2: When the first RSRP exists in the SRP list, the centralized processing unit determines the first base station corresponding to the RSRP;

Step S104-3: The processing unit adds the first base station to the initial clustering.

Based on this, in another optional implementation manner of this embodiment, the centralized processing unit involved in step S106 of the embodiment determines, according to a preset manner, a base station that uses the JT mode and serves the terminal in the final cluster, and uses the CB. The manner of the base station serving in the manner of the terminal can be implemented as follows:

Step S106-1: The centralized processing unit determines the base station that uses the JT mode and serves the terminal in the initial clustering by using the binary method to optimize the terminal rate under the constraint condition of the transmission network capacity and the transmission power limitation. And a base station that uses the CB method and serves the terminal;

Step S106-2: The centralized processing unit uses the exhaustive method, and determines the base station in the final cluster using the JT mode in the transmission mode and serves the terminal, and uses the CB mode in the transmission mode, and maximizes the terminal rate as the optimization target. A base station serving the terminal.

The base station using the JT method and the base station using the CB method involved in the S106-1 and S106-2 can be determined as follows:

(1) A base station that satisfies the following conditions is a base station that uses the JT method:

0≤RSRP _max -RSRP _JT ≤RSRP _threshold -δ

(2) A base station that satisfies the following conditions is a base station that uses the CB mode:

RSRP _threshold -δ≤RSRP _max -RSRP _CB ≤RSRP _threshold

Wherein, where _max is the maximum value of RSRP RSRP list corresponding to a terminal in, to satisfy the formula RSRP conditions employed _JT JT embodiment of the base station the RSRP value corresponding to the list, using the base station RSRP _CB CB corresponding manner to satisfy the condition formula The value in the RSRP list, the RSRP _threshold is a preset fixed threshold; 0 ≤ δ ≤ RSRP _threshold is a variable, wherein the change of the variable causes a change in the correspondence between the terminal and the base station serving the terminal to change the terminal rate.

In addition, for the optimization targets involved in the above S106-1 and S106-2, in the alternative embodiment of the embodiment, the optimization goal of maximizing the terminal rate can be determined by:

The constraints are determined in the following ways:

The method of this embodiment may further include:

Step S108: The central processing unit allocates bandwidth to the base station according to the determined transmission mode used by the base station in the final cluster and the terminal data to be carried, wherein the transmission mode includes a JT mode and a CB mode.

Step S110: The central processing unit receives precoding determined by the base station according to the received training sequence, where the precoding is used to indicate that the base station serving the terminal using the JT mode transmits the spatial wave velocity of the directivity and the bearer data for the terminal, and uses the CB. The base station serving the terminal and the terminal is the terminal avoiding the spatial beam in the direction of the terminal.

Example 2

2 is a second flowchart of a method for clustering according to an embodiment of the present invention. As shown in FIG. 2, the steps of the method include:

Step S202: The base station receives the RSRP list reported by the terminal, where the RSRP list is used to record the RSRP of all base stations that the terminal measures the coverage terminal.

Step S204: The base station sends an RSRP list to the centralized processing unit.

In addition, the method steps of this embodiment may further include:

Step S206: The base station receives the training sequence reported by the terminal.

Step S208: The base station determines channel state information according to the training sequence, and determines to obtain precoding according to the channel state information.

Example 3

In the present embodiment, a clustering device is also provided, which is used to implement the above embodiments and preferred embodiments, and has not been described again. As used below, the term "module" may implement a combination of software and/or hardware of a predetermined function. Although the apparatus described in the following embodiments is preferably implemented in software, hardware, or a combination of software and hardware, is also implemented. Possible and conceived.

FIG. 3 is a structural block diagram of a device for clustering according to an embodiment of the present invention. The device is applied to a centralized processing unit side. As shown in FIG. 3, the device includes: a first receiving module 32 configured to receive a terminal through a base station. RSRP list, wherein the RSRP list is used to record the RSRP of all the base stations of the terminal measurement coverage terminal; the first determining module 34, and the first receiving module 32, are configured to determine the terminal-centered initial clustering according to the RSRP list; The second determining module 36 is coupled to the first determining module 34 and configured to determine a final cluster according to a preset manner, where the base station in the final clustering comprises: a base station that uses the joint transmission JT mode and serves the terminal, and A base station that uses a cooperative beam-enhancing CB mode and serves the terminal.

It should be noted that each of the above modules may be implemented by software or hardware. For the latter, the foregoing may be implemented by, but not limited to, the foregoing modules are all located in the same processor; or, the above modules are in any combination. The forms are located in different processors.

Example 4

4 is a structural block diagram of a device for clustering according to an embodiment of the present invention. The device is applied to a base station side. As shown in FIG. 4, the device includes: a second receiving module 42 configured to receive an RSRP list reported by the terminal. The RSRP list is used to record the RSRP of all the base stations of the terminal that covers the terminal. The sending module 44 is coupled to the second receiving module 42 and configured to send the RSRP list to the centralized processing unit.

Example 5

5 is a structural block diagram of a system for clustering according to an embodiment of the present invention. As shown in FIG. 5, the system includes: a device applied to a centralized processing unit side in Embodiment 3 and a device applied to a base station side in Embodiment 5. .

Example 6

This embodiment 6 is based on the specific embodiments of the foregoing Embodiment 1 to Embodiment 5. This embodiment provides a hybrid CoMP-based transmission mechanism under the C-RAN architecture, which can at least solve the dense deployment in the C-RAN network. Interference problems between base stations and the problem of maximizing user speed in cases where transmission network capacity and transmission power are limited.

First, the algorithm modeling of this embodiment is explained:

The set of base stations is described as N={B ₁ , B ₂ , . . . , B _i , . . . , B _N }, and the set of users is described as K={U ₁ , U ₂ , . . . , U _j , . . . , U _K }; any base station There are N _t transmission antennas, and any user has one receiving antenna. U _j for the user, the user-centric to the base station in a coordinated transmission with clusters JT mode, as represented by D _j U _j services for the user-user transmission JT node and nodes CB CB transmission mode for the user The set of JT nodes, with C _j denotes the set of CB nodes serving the user U _j , and S _j = D _j ∪ C _j denotes the set of all nodes served for the user U _j . Introducing the global matrix D=[d _ij ] _N×K and C=[c _ij ] _{N×K to} describe the relationship between all base stations and users, where

The user U _j receiving signal can be expressed as:

Where α _ij represents a large-scale fading from the base station B _i to the user U _j ,

Representing a small-scale channel fading vector between the base station B _i and the user U _j ,

Indicates a beamforming vector, p _ij is the transmission power allocated by the base station B _i to the user U _j , s _j represents the signal of the user U _j , and n _j represents the noise when the user U _j receives the signal, and the variance is

The first item is a useful signal received by the user. The first item in parentheses is intra-cluster interference. It can be eliminated according to ZF precoding. The second item in parentheses is extra-cluster interference. The user can receive the signal to obtain the user signal-to-noise ratio. :

Optionally, it can be obtained that the user rate of the user U _j on the unit bandwidth is:

R _j =log ₂ (1+SINR _j )

Based on the foregoing modeling algorithm, a user-centric optimized clustering method based on a hybrid CoMP transmission method in the C-RAN architecture proposed by the embodiment includes:

Step S11: The base station sends a reference signal, and the user measures the RSRP of the surrounding multiple base stations, and generates a base station that reports the nearest RSRP list to the user;

Step S12, the base station reports the RSRP list information corresponding to each user to the centralized processing unit through the transmission network;

Step S13: The centralized processing unit determines the initial user-centered clustering according to the RSRP list corresponding to each user. If the RSRP corresponding to a certain base station received by the user satisfies the following formula, the base station joins the initial score centered on the user. cluster:

RSRP _max -RSRP _CoMP ≤RSRP _threshold

The RSRP _max is the maximum value of the RSRP list corresponding to the user, and the RSRP _CoMP is the value in the RSRP list corresponding to the base station that can be added to the initial cluster corresponding to the user, and the RSRP _threshold is a preset fixed threshold.

In step S14, since the C-RAN adopts the TDD system, the downlink channel estimation can be obtained by using the uplink channel estimation. In this step, the user sends a training sequence to the base station in the corresponding initial base station cluster, the base station side calculates the channel state information, and calculates the precoding according to the channel state information, and simultaneously sends the precoding to the centralized processing unit.

In step S15, the centralized processing unit uses the binary method to optimize the user rate as the optimization target under the constraint condition of the transmission network capacity and the transmission power limitation, and initially determines the base station and the use of the JT service for the user in the initial clustering. The CB mode is a base station serving the user.

In step S16, the centralized processing unit further uses the exhaustive method in a small range, and also optimizes the user rate as the optimization target, and finally determines the base station in the cluster that uses the JT mode to serve the user and the base station that uses the CB mode to serve the user.

Step S17: The baseband resource centralization management unit allocates bandwidth to the base station according to the transmission mode used by the base station and the user data carried by the base station.

Step S18: The base station serving the user by using the JT mode transmits a directional spatial beam carrying user data to the user, and the base station serving the user by using the CB mode circumvents the spatial beam in the user direction for the user.

It should be noted that, in the step 5, the present patent proposes a framework for hierarchically deploying a base station using a JT method and a base station node using a CB method, that is, on the basis of initializing clustering, the following formula is satisfied. The serving base station is set to the serving base station of the JT mode:

0≤RSRP _max -RSRP _JT ≤RSRP _threshold -δ

The serving base station that satisfies the following formula is set as the serving base station in the CB mode:

RSRP _threshold -δ≤RSRP _max -RSRP _CB ≤RSRP _threshold

Wherein, 0≤δ≤RSRP _threshold is a variable, and the change of the variable causes a change of the global matrix D and C, that is, a correspondence between the user and the base station serving the user, thereby changing the rate of the user.

At the same time, it is necessary to specifically specify that in the step S15, under the constraint condition of the limited capacity and transmission power of the transmission network, the optimal solution of δ is found by the dichotomy method to maximize the user rate, thereby initially determining the hybrid CoMP. A base station in a transmission mechanism that transmits in two hybrid ways.

Optionally, calculate the system user rate according to the following formula to determine the optimization goal:

Where β _j is the scheduling priority weight of user j. Determine the constraints:

Wherein, P _i and C _i are the maximum transmission power of the base station B _i and the transmission capacity between the base station and the centralized processing unit, respectively.

The specific application scenario may be as follows:

In step S15-1, the initialization iteration factor r=0, the initialization variable δ takes the value field boundary value, that is, a(0)=0, b(0)=RSRP _threshold . The initialization result accuracy Tolerance = η, where η is a very small positive number. Initialize the intermediate variable c=0.

Step S15-2, calculating f(δ)| _δ=a(r) and f(δ)| _δ=b(r) ,

If f(δ)| _δ=a(r) ≤f(δ)| _δ=b(r) , let a(r+1)=c,b(r+1)=b(r), otherwise, let a(r+1)=a(r), b(r+1)=c.

In step S15-3, step S15-2 is repeated until [a](a)-b(r)|?n or the constraint is not satisfied.

In step S15-4, a preliminary optimization result δ ₀ = c is obtained.

At the same time, it should be specifically noted that, in the step S16, the preliminary optimization result obtained in step S15 is further optimized. If δ ₀ obtained in step S15 is the upper boundary of (δ _{0 -} η, δ ₀ ) or the lower boundary of (δ ₀ , δ ₀ + η) due to the limitation of the accuracy η, neither case affects step S16. To proceed, let δ ₀ be the upper boundary of (δ _{0 -} η, δ ₀ ). In the other case, the following steps are equally applicable.

The specific application scenario of step S16 can be:

In step S16-1, j=1 is initialized.

Step S16-2, the base stations which establish a set of user U _j to be the optimum range:

L _j ={B _i |RSRP _threshold -δ ₀ <RSRP _max -RSRP _i <RSRP _threshold -δ ₀ +η}

Step S16-3, if

Go to step S16-4;

L _j is traversed in each base station, for B _i ∈L _j, taking

Step S16-4, j=j+1, if j≤K, return to step S16-2; if j>K, the algorithm ends.

The above manner of the embodiment can simultaneously maximize the frequency band utilization in the case of network system resources such as transmission network capacity and transmission power, and can at least solve the interference problem between the densely deployed base stations in the C-RAN network and in the transmission. The problem of maximizing user speed in case of limited network capacity and transmission power.

Example 7

6 is a schematic diagram of a system model according to an embodiment of the present invention, as shown in FIG. 6, 101 is The baseband unit processing pool BBU pool, S102 is a transmission network with limited capacity, and part 103 shows the model that the radio remote unit RRU cooperates for user transmission. 105, 107, and 109 use the JT mode to cooperate with the user 106. The three RRUs are user-assisted transmission of user data; 107, 109, and 111 simply use the CB mode to serve the

user

110, and 111 to transmit the user data for the user, 107 And 109 cooperate to circumvent the beam in the user direction; 104, 105, and 109 cooperate to serve the user 108 in a CB and JT mixed mode, 104 and 108 cooperate to transmit user data for the user, and 105 cooperate to circumvent the beam in the user direction.

The user-centered optimized clustering method based on the hybrid CoMP transmission method includes:

Step S301: The base station sends a reference signal, and the user measures the RSRP of the surrounding multiple base stations, and generates a base station that reports the latest RSRP list of the user;

Step S302: The base station reports the RSRP list information corresponding to each user to the centralized processing unit through the transmission network;

Step S303: The centralized processing unit determines the initial clustering centered on the user according to the RSRP list corresponding to each user. If the RSRP corresponding to a certain base station received by the user satisfies the following formula, the base station joins the initial score centered on the user. cluster:

RSRP _max -RSRP _CoMP ≤RSRP _threshold

Step S304: Since the C-RAN adopts the TDD system, the downlink channel estimation can be obtained by using the uplink channel estimation. In this step, the user sends a training sequence to the base station in the corresponding initial base station cluster, the base station side calculates the channel state information, and calculates the precoding according to the channel state information, and simultaneously sends the precoding to the centralized processing unit;

Step S305: The centralized processing unit uses the binary method to optimize the user rate as the optimization target under the constraint condition of the transmission network capacity and the transmission power limitation, and initially determines the base station and the use of the JT service for the user in the initial clustering. The CB mode is a base station serving the user.

Step S306: The centralized processing unit further uses the exhaustive method in a small range, and also the most The user rate is optimized, and the base station in the cluster that uses the JT mode to serve the user and the base station that uses the CB mode to serve the user are finally determined.

Step S307: The baseband resource centralization management unit allocates bandwidth to the base station according to the transmission mode used by the base station and the user data carried by the base station.

Step S308: The base station serving the user by using the JT mode transmits a directional spatial beam carrying the user data to the user, and the base station serving the user by using the CB mode circumvents the spatial beam in the direction of the user.

The method steps for the preliminary optimization algorithm of the dichotomy method involved in the above steps S301 to S308 include

Step S401: Initialize the iteration factor r=0, and initialize the variable δ to take the value field boundary value, that is, a(0)=0, b(0)=RSRP _threshold . The initialization result accuracy Tolerance = η, where η is a very small positive number. Initialize the intermediate variable c=0;

Step S402: calculating f(δ)| _δ=a(r) and f(δ)| _δ=b(r) ,

Step S403: determining whether there is f(δ)| _δ=a(r) ≤ f(δ)| _{δ=b(r) is} established, if yes, go to step S404, otherwise go to step S405;

Step S404: Let a(r+1)=c, b(r+1)=b(r);

Step S405: Let a(r+1)=a(r), b(r+1)=c;

Step S406: determining whether |a(r)-b(r)|≤η holds or does not satisfy the constraint condition, if yes, proceed to step S407, otherwise go to step S402;

Step S407: A preliminary optimization result δ ₀ = c is obtained.

For the method of the exhaustive optimization algorithm involved in the above steps S301 to S308, the steps of the method include:

Step S501: Initializing j=1;

Step S502: Establish a set of base stations in the to-be-optimized range of the user U _j according to the following formula:

Step S503: determining whether there is any

If yes, go to step S505, otherwise go to step S504;

Step S504: L _j traversing the respective base stations, for B _i ∈L _j, taking

Step S505: j=j+1;

Step S506: determining whether there is j>K, if yes, the algorithm ends, otherwise, the process goes to step S502.

Embodiments of the present invention also provide a storage medium. Optionally, in the embodiment, the foregoing storage medium may be configured to store program code for performing the following steps:

Step S1: The central processing unit receives the RSRP list reported by the terminal through the base station, where the RSRP list is used to record the RSRP of all base stations of the terminal that measure the coverage terminal;

Step S2: The centralized processing unit determines the initial cluster centered on the terminal according to the RSRP list;

Step S3: The centralized processing unit determines a final cluster according to a preset manner, where the base station in the final cluster includes: a base station that uses the JT mode and serves the terminal, and a base station that uses the CB mode and serves the terminal.

Step S1: The base station receives the RSRP list reported by the terminal, where the RSRP list is used to record the RSRP of all base stations that the terminal measures the coverage terminal;

Step S2: The base station sends an RSRP list to the centralized processing unit.

Step S3: The base station receives the training sequence reported by the terminal;

Step S4: The base station determines channel state information according to the training sequence, and determines to obtain precoding according to the channel state information.

For example, the specific examples in this embodiment may refer to the examples described in the foregoing embodiments and the optional embodiments, and details are not described herein again.

It will be apparent to those skilled in the art that the various modules or steps of the present invention described above can be implemented by a general-purpose computing device that can be centralized on a single computing device or distributed across a network of multiple computing devices. Alternatively, they may be implemented by program code executable by the computing device such that they may be stored in the storage device by the computing device and, in some cases, may be different from the order herein. The steps shown or described are performed, or they are separately fabricated into individual integrated circuit modules, or a plurality of modules or steps thereof are fabricated as a single integrated circuit module. Thus, the invention is not limited to any specific combination of hardware and software.

The above description is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Industrial applicability

In the embodiment of the present invention, the centralized processing unit receives the RSRP list reported by the terminal through the base station, and determines the initial clustering centered on the terminal according to the RSRP list, and then determines the JT mode and uses the terminal service in the final cluster according to a preset manner. Base station, and a base station that uses the CB mode and serves the terminal, that is, the base station is divided into a base station using the JT mode and the CB mode, so that the base station can simultaneously maximize the use of network system resources such as transmission network capacity and transmission power. The frequency band, thereby solving the problem of interference between base stations densely deployed in a C-RAN network in the related art.

Claims

A method of clustering, comprising:

The centralized processing unit receives a reference signal received power RSRP list reported by the terminal by the base station, where the RSRP list is used to record that the terminal measures the RSRP of all base stations covering the terminal;

The centralized processing unit determines an initial clustering centered on the terminal according to the RSRP list;

The centralized processing unit determines a final cluster according to a preset manner, where the base station in the final cluster includes: a base station that uses the joint transmission JT mode and serves the terminal, and uses a cooperative beam-based CB method and is The base station of the terminal service.
The method according to claim 1, wherein the central processing unit determines that the initial clustering centered on the terminal according to the RSRP list comprises:

The centralized processing unit determines whether there is a first RSRP that satisfies a preset condition in the RSRP list;

When the first RSRP exists in the RSRP list, the centralized processing unit determines a first base station corresponding to the RSRP;

The centralized processing unit adds the first base station to the initial cluster.
The method of claim 2 wherein said predetermined condition is:

RSRP max -RSRP CoMP ≤RSRP threshold

The RSRP max is a maximum value in the RSRP list corresponding to the terminal, and the RSRP CoMP is a value corresponding to the base station that joins the initial clustering in the RSRP list, and the RSRP threshold is a preset fixed threshold.
The method according to claim 1, wherein the centralized processing unit determines, according to a preset manner, a base station in a final cluster that uses the JT mode and serves the terminal, and a base station that uses the CB mode and serves the terminal includes :

The centralized processing unit determines, by using a binary method, a maximum terminal rate as an optimization target under the constraint of transmission network capacity and transmission power limitation, determining, in the initial clustering, using the JT mode and serving the terminal. a base station, and a base station that uses the CB mode and serves the terminal;

The centralized processing unit uses an exhaustive method, and determines a base station that uses the JT mode in the transmission mode and serves the terminal in the final clustering with the maximum terminal rate as the optimization target, and uses the CB mode in the transmission mode and is The base station served by the terminal.
The method of claim 4, wherein

A base station that satisfies the following conditions is a base station that uses the JT method:

0≤RSRP max -RSRP JT ≤RSRP threshold -δ

A base station that satisfies the following conditions is a base station that uses the CB mode:

RSRP threshold -δ≤RSRP max -RSRP CB ≤RSRP threshold

Wherein, the RSRP max is a maximum value in the RSRP list corresponding to the terminal, and the RSRP JT is a value in the RSRP list corresponding to the base station that uses the JT method that satisfies the formula condition, and the RSRP CB uses the CB to satisfy the formula condition. The value of the RSRP threshold in the RSRP list corresponding to the base station of the mode is a preset fixed threshold; 0≤δ≤RSRP threshold is a variable, wherein the change of the variable causes the terminal and the base station serving the terminal The change in correspondence between the two to change the rate of the terminal.
The method of claim 4, wherein

The optimization goal of maximizing the terminal rate is determined by:

Where K is the total number of terminals, and β j is the scheduling priority weight of terminal j;

The constraints are determined by:

Where d ij and w ij are the i-th row and j-th column elements in the JT matrix and the precoding matrix, respectively; R j is the terminal rate of the jth terminal; P i and C i are the maximum transmission power of the base station B i , respectively And a transmission capacity between the base station and the centralized processing unit.
The method of claim 4 wherein the method further comprises:

The centralized processing unit allocates bandwidth to the base station according to the determined transmission mode used by the base station in the final cluster and the terminal data carried by the base station, where the transmission mode includes a JT mode and a CB mode.
The method of claim 1 wherein the method further comprises:

The centralized processing unit receives precoding determined by the base station according to the received training sequence, where the precoding is used to indicate that the base station serving the terminal by using the JT mode transmits directionality and carries data for the terminal. The spatial wave velocity, and the base station serving the terminal using the CB mode, circumvent the spatial beam in the direction of the terminal for the terminal.
A clustering method, which includes:

The base station receives the RSRP list reported by the terminal, where the RSRP list is used to record that the terminal measures the RSRP of all the base stations that cover the terminal;

The base station sends the RSRP list to a centralized processing unit.
The method of claim 9 wherein the method further comprises:

Receiving, by the base station, a training sequence reported by the terminal;

The base station determines channel state information according to the training sequence, and determines to obtain precoding according to the channel state information.
A clustered device is applied to a centralized processing unit side, wherein:

a first receiving module, configured to receive, by the terminal, an RSRP list reported by the base station, where the RSRP list is used to record, by the terminal, an RSRP of all base stations that cover the terminal;

a first determining module, configured to determine, according to the RSRP list, an initial clustering centered on the terminal;

a second determining module, configured to determine a final cluster according to a preset manner, where the base station in the final cluster includes: a base station that uses the joint transmission JT mode and serves the terminal, and uses a cooperative beam-based CB mode and A base station serving the terminal.
A clustered device is applied to a base station side, including:

a second receiving module, configured to receive an RSRP list reported by the terminal, where the RSRP list is used to record, by the terminal, an RSRP of all base stations that cover the terminal;

The sending module is configured to send the RSRP list to the centralized processing unit.
A clustered system, comprising: the device of claim 11 applied to the centralized processing unit side and the device of claim 12 applied to the base station side.