WO2012058963A1

WO2012058963A1 - Base station interacting method and device

Info

Publication number: WO2012058963A1
Application number: PCT/CN2011/078280
Authority: WO
Inventors: 黄双红; 王文焕; 卢有雄; 刘敏
Original assignee: 中兴通讯股份有限公司
Priority date: 2010-11-01
Filing date: 2011-08-11
Publication date: 2012-05-10
Also published as: WO2012058984A1; CN102457434A; CN102457434B

Abstract

A base station interacting method is disclosed, comprising: processing, by a communication system, base station interaction information, on a MAC layer, and then interacting through an interface physically connected to a network layer or a data link layer. A base station interacting device is further disclosed. Through the present invention, a smaller interaction delay is achieved, so as to meet requirements of more systems and transmission scenarios.

Description

Method and device for base station interaction

The present invention relates to the field of wireless communications, and in particular to a method and apparatus for base station interaction. Background technique

The LTE (Long Term Evolution) project is an evolution of 3G. It improves and enhances 3G air access technology, using OFDM (Orthogonal Frequency Division Multiplexing) and MIMO (Multi-Input Multiple- Output, Multiple Input Multiple Output) is the fundamental technology for the evolution of its wireless network. The overall architecture of the LTE system is shown in Figure 1. The access network is composed of an eNB (evolved NodeB, evolved base station), and the eNBs are interconnected through an X2 interface. Each eNB passes the S1 interface and the EPC (Evolved Packet Core). The core network is connected to the MME (Mobility Management Entity) through the S1-MME interface, and is connected to the S-GW (Serving Gateway) through the S1-U interface. The UE (User Equipment) is connected to the LTE system through the eNB, and the UE and the eNB are connected by the Uu interface.

In the current LTE system, data exchange during cell handover is performed through the X2 interface, and the user information protocol of the X2 interface is exchanged, and the transport network layer is based on UDP (User Datagram Protocol) and IP (Internet Protocol, Internet). Protocol) for data transmission, using the User Interface GTP-U (GPRS Tunneling Protocol-User plane, GPRS Tunneling Protocol) on the UDP/IP protocol to transmit the PDU (Protocol Data Unit) of the user plane between the eNBs. Currently, there is a certain data interaction delay through the interaction of the X2 interface, including the internal processing delay of the eNB, the node switching and the routing delay, and the transmission delay between the nodes. This delay is too large for some scenarios to meet the system's latency requirements. The concept of CoMP was proposed at the 3GPP RANI 53# conference. CoMP technology can better overcome inter-cell interference, improve the edge and average throughput of the system, and further expand the coverage of the cell through coordinated transmission of multiple nodes in the mobile network. The downlink CoMP is divided into two modes: JP (Joint Processing) and CS/CB (Coordinated Scheduling/Beamforming). Figure 2 shows a downlink CoMP system with dual base station dual UE CS/CB transmission modes. Network diagram. To achieve coordinated transmission of multiple nodes, CoMP technology needs to exchange more data through the X2 interface than in the non-cooperative mode, except for the original information about the handover, and the data of the downlink channel matrix fed back by the UE. These downlink channel matrices The data needs to be quickly exchanged between the serving cell base station and the coordinated cell base station. If the existing X2 interface of the LTE system interacts, the delay is difficult to meet the requirements. Summary of the invention

The main purpose of the present invention is to provide a method and a device for interacting with a base station, so as to solve the problem that the data interaction delay is difficult to meet the system requirements when interacting through the X2 interface.

According to an aspect of the present invention, a method for base station interaction is provided, including: a communication system interacts with an interface that is physically connected by a network layer or a data link layer after the base station interaction information is processed by the MAC layer.

The communication system is an LTE R8 system or a CoMP system.

The base station interaction information is information that needs to be shared between the base stations, and specifically includes uplink channel information and downlink channel information of the CoMP system, or cell handover information of the R8 system.

The uplink channel information and the downlink channel information of the CoMP system include: a channel gain matrix H or a channel gain autocorrelation matrix 1, scheduling information, a channel quality indicator CQI, a precoding matrix indication PMI, and a rank indication RI.

The processing of the base station interaction information at the MAC layer includes: grouping and unpacking the base station interaction information.

The physical connection interface includes a Gigabit Ethernet GE interface and a transmission based on the transport layer below Interface.

According to another aspect of the present invention, an apparatus for interacting with a base station is provided, including: a processing module, located at a medium access control (MAC) layer, configured to process base station interaction information in a communication system; and a connection module, configured to connect The physical interface between the neighboring base stations is configured with each interface protocol. The interaction module is configured to implement interaction between the base station interaction information outputted by the processing module based on the network layer or the data link layer through the connection module.

The processing of the base station interaction information in the processing module includes: grouping and unpacking of the base station interaction information.

The base station interaction information in the processing module is information that needs to be shared between the base stations, and specifically includes uplink channel information and downlink channel information of the CoMP system, or cell handover information of the R8 system.

The physical interfaces in the connection module include a Gigabit Ethernet GE interface and a transport interface based on the transport layer.

The present invention directly performs data transmission at the protocol layer below the transport layer in the definition of the seven-layer model of the OSI (Open System Interconnect). Compared with the current method of interacting through the X2 interface in the R8, a smaller interaction delay can be obtained. , to meet the needs of more systems and the needs of transmission scenarios. DRAWINGS

The drawings described herein are intended to provide a further understanding of the present invention, and are intended to be a part of the present invention, and the description of the present invention is not intended to limit the invention. In the drawing:

FIG. 1 is a schematic diagram of a general structure of a system of LTE;

2 is a schematic diagram of a downlink CoMP system network in a CS/CB transmission mode of a dual base station dual UE; FIG. 3 is a schematic flowchart of a method for base station interaction according to an embodiment of the present invention;

4 is a schematic diagram of an interaction system according to Embodiment 1 of the present invention;

FIG. 5 is a schematic diagram of interaction of base station interaction information according to Embodiment 1 of the present invention; FIG. FIG. 6 is a flowchart of interaction between a channel matrix and an optimal precoding matrix according to Embodiment 1 of the present invention; FIG. 7 is a schematic diagram of a physical connection manner of an interaction system according to Embodiment 2 of the present invention;

8 is a flowchart of data interaction in a cooperative transmission mode according to Embodiment 2 of the present invention; FIG. 9 is a schematic diagram of an interaction system of a real-time three according to the present invention;

10 is an interaction flowchart of a real-time three channel matrix and an optimal precoding matrix according to the present invention; FIG. 11 is a schematic structural diagram of a device for base station interaction according to the present invention. detailed description

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.

The main idea of the base station interaction method of the present invention is as follows: The communication system interacts with the interface physically connected by the network layer or the data link layer after the base station interaction information is processed at the MAC layer.

According to an embodiment of the present invention, a method for base station interaction is provided. As shown in FIG. 3, the method includes:

Step S101: Processing base station interaction information at the MAC layer;

Step S102: The interaction of the interaction information between the communication systems is completed through an interface physically connected by the physical layer or the data link layer.

With this embodiment, data transmission is directly performed at the protocol layer below the transport layer in the definition of the OSI seven-layer model. Compared with the current method of interacting through the X2 interface in the R8, a smaller interaction delay can be obtained to meet the requirements of more systems. And the need to transfer the scene.

Further, the above communication system is an LTE R8 system or a CoMP system. The foregoing base station interaction information is information that needs to be shared between the base stations, and specifically includes uplink channel information and downlink channel information (CoMP system) of the CoMP system, or cell handover information (LTE R8 system) of the R8 system.

Further, the uplink channel information and the downlink channel information of the CoMP system include: a channel gain matrix H or a channel gain autocorrelation matrix 1, scheduling information, a channel quality indicator CQI, a precoding matrix indicator PMI, and a rank indicator RI. The step of processing the base station interaction information by the MAC layer includes the grouping and unpacking of the base station interaction information.

The above physically connected interfaces include a Gigabit Ethernet GE interface and a transport interface based on the transport layer below.

The above transport layer refers to the transport layer defined in the seven-layer model of OSI (Open System Interconnect). The protocol encapsulation without the transport layer does not follow the user plane protocol of the current X8 interface in R8, including not using GTP. -U transmits the PDU of the user plane, but directly performs data transmission based on the network layer or the data link layer below the transport layer.

Embodiment 1

This embodiment is an implementation of a downlink CoMP system based on the CS/CB transmission scheme shown in FIG. 2. Interaction flow station exchanging information UE1 measured channel matrix H "and H _12, and all reactions to eNBl, eNBl the H ₁₂ interact to the eNB2; likewise UE2 measured channel matrix obtained H ₂₁ and H ₂₂ are fed back to the eNB2, eNB2 interacts with H ₂₁ to eNB _1. eNB1 calculates the optimal precoding matrix using H _u and 2 ₁ eNB2 calculates the optimal precoding matrix W ₂ using H ₂₂ and H _12. eNB1 will then interact with eNB2, and eNB2 will again ₂ interacts with eNB1 for calculating the respective CQI.

Figure 4 is a schematic diagram of the interaction system in this embodiment. Each of the interworking base stations adds a GE network port, and the network port is connected to the core network through a switch through a network cable.

FIG. 5 is a schematic diagram of interaction of information exchange between base stations in this embodiment. The channel matrix H^i = 1, 2; ≠ _/·) and the optimal precoding matrix W (= l, 2) have large data volume, and are in X2. It is difficult for the interface to complete the inter-base station interaction to meet the performance requirements of the system. The channel matrix and the optimal precoding matrix are connected through the GE network port. The Socket interface function is directly called to send and receive data at each base station through the Socket number. The user quilt packet protocol process greatly reduces the interaction delay. The other base station interaction information completes the interaction between the base stations through the X2 interface, so that the interaction resources are allocated reasonably. FIG. 6 is a flow chart of interaction between the channel matrix and the optimal precoding matrix in the embodiment, and the specific process includes the following steps:

Step 601: Each base station determines an interaction set according to a channel matrix fed back by the UE, and updates a routing table of the base station;

Step 602: Each base station creates a Socket (socket) according to the source base station IP and the destination base station IP, and configures the port number of each Socket. The port numbers of different Sockets are different, and the interaction data between the base stations is based on the IP address and the Socket. The port number is sent and received, and at the same time, the interface function of the Socket sending and receiving is encapsulated;

Step 603: The base station groups and unpacks the channel matrix that needs to be exchanged to the neighboring base station at the MAC layer, and binds the corresponding IP address and the Socket port number according to the cell ID in the channel matrix.

Step 604: The base station sends an interface function sent by the Socket according to the IP address and the Socket port number of each base station in the cooperation set, and sends the channel matrix of the corresponding neighboring cell to the corresponding base station, and also calls the interface function received by the Socket to receive the neighboring cell. The channel matrix corresponding to the UE to the neighboring cell UE is sent, and the interaction of the channel matrix is completed. The channel matrix of the interaction is H.^j = 1, 2; i≠ j), and the interaction of the entire channel matrix is through the GE network port. Step 605: The base station calculates the most serving cell according to the maximum signal to noise ratio principle according to the channel matrix of the serving cell _3⁄4 (= 1, 2) and the interleaved channel matrix ^ (! '=1, 2; i≠ Excellent precoding matrix ( = l, 2);

Step 606: Invoking an interface function sent and received by the Socket, and interacting with the optimal precoding matrix through the GE network port, and interacting W(=l, 2) of the current cell to the coordinated set neighboring cell base station, for calculating

CQI.

The above steps 604, 605 and 606 can be designed to operate in a pipeline mode. The GE network port is a full-duplex working mode. When calculating the optimal precoding matrix of the current subframe, the optimal precoding of the previous subframe can be simultaneously performed. The matrix of the matrix and the subsequent sub-frame.

At the same time, other messages that need to be exchanged between the base stations can be interacted through the X2 interface. The interaction path together completes the data interaction between the base stations, and can meet the system delay requirement when the amount of interaction data needs to be huge.

Embodiment 2

The interaction method of the second embodiment is the same as that of the first embodiment, but the physical connection manner of the interactive system is different. As shown in FIG. 7, the data interaction of the Socket interface function based on the IP transmission is directly in the X2 interface. The physical interface is implemented without adding a GE network port. That is, the direct interaction based on IP transmission proposed by the present invention and the existing X2 based protocol of LTE share the same physical interface.

In the scenario of the non-cooperative transmission mode, when the handover of the UE in the connected state in the LTE access system is performed in the same MME, the handover procedure does not involve changes of the MME and the S-GW.

In this interaction scenario, the interaction information required for the handover may be exchanged through the original X2 interface protocol flow, or may be directly invoked based on the IP transmission call Socket interface function according to the method proposed by the present invention.

Figure 8 is a flow chart of data interaction in the non-cooperative transmission mode. When interacting by IP transmission, the base station acquires the IP address of the target base station from the measurement information of the UE or the RRM (Radio Resource Management) information, and updates the routing table of the base station to indicate the source base station and The IP address of the target base station; then create a Socket according to the IP of the target base station and the source base station, configure the port number of the Socket, and encapsulate the interface function for sending and receiving the Socket; when interacting with the data, directly call the Socket interface function to send or receive data.

Embodiment 3

The third embodiment is also an implementation of the downlink CoMP system based on the CS/CB transmission mode shown in FIG. 2. The third embodiment is to implement the connection and interaction between neighboring base stations through an ATM (Asynchronous Transfer Mode) interface. The interface also includes a physical interface that can be directly transmitted based on the transport layer. FIG. 9 is Embodiment 3. Schematic diagram of the interactive system, phase The neighbor base station is connected to the ATM network through the ATM switch, and the interaction data is implemented through the ATM network based on the data link layer.

FIG. 10 is a flow chart of interaction between the channel matrix and the optimal precoding matrix of the embodiment, and the specific process includes the following steps:

Step A01: Each base station determines an interaction set according to the channel matrix fed back by the UE, and updates the routing table, VPI and VCI according to the VPI (Virtual Path Identifier) and the VCI (Virtual Channel Identifier) of the base station. Identifying a virtual circuit connection; Step A02: Each base station establishes a virtual circuit connection according to the source base station VPI and the destination base station VPI, and the ATM is a connection-oriented exchange mode;

Step A03: The base station groups and unpacks the channel matrix that needs to be exchanged to the neighboring base station at the MAC layer, and writes the corresponding VPI and VCI to the header position of the cell according to the cell ID in the channel matrix, and according to the fixed length of the cell. Group packet, the cell is the basic carrier for ATM to transmit information;

Step A04: The ATM network transmits or receives the interaction data according to the virtual circuit connection flag of the letterhead, and completes the interaction of the channel matrix, and the channel matrix of the interaction is ^(Ϊ·, _/· = 1, 2; i≠ j);

Step A05: The base station calculates the optimal precoding matrix of the serving cell according to the channel matrix of the serving cell (= 1, 2) and the interleaved channel matrix ^ (! ' = 1, 2; i ≠ according to the principle of maximum signal leakage ratio ( = l, 2) ;

Step A06: Perform an optimal precoding matrix through the ATM network again, and ^(? = 1, 2) of the 4th cell to the coordinated set neighbor cell base station, for calculating the CQI;

ATM combines the advantages of circuit switching and packet switching, that is, ATM takes into account the advantages of packet switching mode statistical multiplexing, flexible and efficient, and circuit switching mode with small transmission delay and good real-time performance. It can obtain less delay than the existing X2 interface of the LTE system, and can meet the scene requirements of large data volume interaction. At the same time, ATM does not exclude the X2 interface, and other base station interaction information can choose X2 interface interaction.

According to an embodiment of the present invention, a device for interacting with a base station is provided, as shown in FIG. The components include: a processing module 2, a connection module 4, and an interaction module 6. The above results are described in detail below.

The processing module 2 is located at the MAC layer and is used for processing base station interaction information in the communication system. The connection module 4 is connected to the processing module 2, and is configured to connect physical interfaces between adjacent base stations, and configure each interface protocol. The interaction module 6 is connected to the connection. The module 4 is configured to implement interaction between the base station interaction information outputted in the processing module by using a connection module based on a network layer or a data link layer.

Further, the processing step of the base station interaction information in the foregoing processing module includes the grouping and unpacking of the base station interaction information. The base station interaction information in the foregoing processing module is information that needs to be shared between the base stations, and specifically includes uplink channel information and downlink channel information of the CoMP system, or cell handover information of the R8 system. The physical interfaces in the above connection modules include a Gigabit Ethernet GE interface and a transport interface based on the transport layer below.

The implementation process of the base station interaction apparatus is further described below by way of an embodiment. First, in the processing module 2, the channel matrix fed back to the UE is determined to determine the interaction set, and the routing table of the base station is updated; in the connection module 4, a Socket is created according to the source base station IP and the destination base station IP, and the port number of each Socket is configured, and different Sockets are configured. The port numbers are different. The interaction data between the base stations will be sent and received according to the IP address and the Socket port number. At the same time, the interface function of the Socket transmission and reception is encapsulated, and the corresponding IP is bound according to the cell ID in the channel matrix. The address and the Socket port number; in the interaction module 6, according to the IP address and the Socket port number of each base station in the cooperation set, the interface function sent by the Socket is called, and the channel matrix of the corresponding neighboring cell is sent to the corresponding base station, and the Socket reception is also called. interface function receives the transmission from the neighbor cell to the counterpart of the cell channel matrix to neighbor cells of the UE to complete the interactive channel matrix, a channel matrix interactions is _{H 7; = l, 2;} i ≠ j); in the processing module 2 Calculate the optimal precoding matrix = 1, 2), and the interaction module 6 calls the Socket interface function to exchange the optimal precoding matrix through the GE network port. The 0· = 1, 2) of the current cell interacts with the coordinated set neighbor cell base station and is used to calculate the CQI.

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

The above 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. within the spirit and scope of the invention are intended to be included within the scope of the invention.

Claims

Claim

A method for interacting with a base station, comprising:

The communication system interacts with the base station interaction information at the MAC layer and through the physical interface of the network layer or the data link layer.

2. The method of claim 1 wherein:

The communication system is an LTE R8 system or a CoMP system.

The method according to claim 1, wherein the base station interaction information is information that needs to be shared between the base stations, and specifically includes uplink channel information and downlink channel information of the CoMP system, or cell handover information of the R8 system. .

The method according to claim 3, wherein the uplink channel information and the downlink channel information of the CoMP system comprise: a channel gain matrix H or a channel gain autocorrelation matrix R, scheduling information, a channel quality indicator CQI, a pre- The coding matrix indicates the PMI and the rank indication RI.

The method according to claim 1, wherein the processing, at the MAC layer, the base station interaction information comprises: grouping and unpacking the base station interaction information.

6. The method according to claim 1, wherein the physical connection interface comprises a Gigabit Ethernet GE interface and a transport interface based on a transport layer or lower.

7. A device for interacting with a base station, comprising:

a processing module, located at a medium access control (MAC) layer, for processing base station interaction information in the communication system;

The connection module is configured to connect the physical interface between the adjacent base stations, and configure each interface protocol. The interaction module is configured to implement interaction between the base station interaction information outputted in the processing module based on the network layer or the data link layer through the connection module.

The device according to claim 7, wherein the processing of the base station interaction information in the processing module comprises: grouping and unpacking the base station interaction information.

9. The apparatus according to claim 7, wherein the base station interacts in the processing module The information is information that needs to be shared between the base stations, and specifically includes uplink channel information and downlink channel information of the CoMP system, or cell handover information of the R8 system.

10. The apparatus according to claim 7, wherein the physical interface in the connection module comprises a Gigabit Ethernet GE interface and a transmission interface based on a transport layer or lower.