WO2012065419A1

WO2012065419A1 - Method, system and cascade processing logic subsystem for implimenting base station cascade

Info

Publication number: WO2012065419A1
Application number: PCT/CN2011/074452
Authority: WO
Inventors: 佘金桂; 吴学德; 谭海青
Original assignee: 中兴通讯股份有限公司
Priority date: 2010-11-17
Filing date: 2011-05-20
Publication date: 2012-05-24
Also published as: CN102006208A

Abstract

A method, a system and a cascade processing logic subsystem for implementing base station cascade are provided by the invention. The method adopts different media for connecting a Base Station Controller (BSC) (4) and a lower-level base station (2) at the two sides of an upper-level base station (1). The upper-level base station (1) and the BSC (4) are connected by an E1/T1 line, while the upper-level base station (1) and the lower-level base station (2) are connected by Ethernet; the cascade processing logic subsystem (3) is used for implementing the functions of flow control and congestion scheduling. The base station cascade mode of the present invention realizes dynamic sharing of bandwidth, reduces cost, improves network building flexibility and improves capacity of the cascaded base stations.

Description

Method, system and cascade processing logic subsystem for implementing base station cascading

The present invention relates to a base station connection technology in the field of mobile communications, and in particular, to a method, system and cascade processing logic subsystem for implementing base station cascading through different transmission media. Background technique

At present, in the field of communication, there are multiple transmission media in network transmission, such as El, Tl, Ethernet, and the like. Traditional E1/T1 lines are used in existing network transmissions. E1/T1 stands for two data transmission rate standards, of which E1 is a European standard with a rate of 2.048 Mbps; T1 is a North American standard with a rate of 1.544 Mbps. In the mobile network, the connection between the base station and the base station controller (BSC) uses the E1/T1 line transmission mode. In order to make full use of the bandwidth resources, generally, a plurality of lower base stations are connected in the cascading of the base station, that is, each base station (referred to as a higher-level base station) connected to the base station controller, and then reconnected to multiple base stations through a certain transmission medium. (referred to as a lower base station), all base stations accessing the base station controller in a cascade manner are collectively referred to as a cascade base station. The cascading mode of the base station can make full use of the E1/T1 line transmission resources provided by the base station controller or the Radio Network Controller (RNC) to improve the transmission efficiency.

When the base station is cascaded, the upper base station and the base station controller are connected by the transmission medium, and the upper base station is connected to the plurality of lower base stations through the transmission medium, thereby forming a cascade manner of the upper and lower two-level base stations. At present, the transmission medium used in the two-stage cascade interface uses the E1/T1 line, that is, the connection between the upper base station and the base station controller, and uses the E1/T1 line; the access of the lower base station also uses E1/T1. line. In this connection mode, the bandwidth of each lower-level base station is exclusive, and the total bandwidth of each lower-level base station is the bandwidth provided by the upper-level E1/T1, and the bandwidth provided by E1/T1 is allocated to the lower-level base station by the method of time slot separation. The bandwidth occupied by each subordinate base station is fixed and exclusive, even when it does not use bandwidth resources, other subordinate base stations cannot be used. This has caused a waste of bandwidth resources. In addition, if multiple upper-level base stations need to be accessed through the upper-level base station, multiple ports must be configured, resulting in a lack of flexibility in networking. Summary of the invention

In view of this, the main purpose of the present invention is to provide a method, a system, and a cascading processing logic subsystem for implementing base station cascading, which can save bandwidth resources and improve networking flexibility.

In order to achieve the above object, the technical solution of the present invention is achieved as follows:

A method for implementing cascading of a base station, where an upper base station and a network side are connected by an E1/T1 line, and an upper Ethernet line is connected between the upper base station and the lower base station;

The method also includes:

The upper base station uniformly receives data packets and forwards the received data packets between different transmission media.

The lower base station is one;

The lower base station and the upper base station are directly connected by a network cable.

The method further includes: setting a gateway IP address of the lower-level base station to a gateway IP address of the upper-level base station to which the base station belongs, and the data packet is uniformly received by the upper-level base station.

After receiving the data packet, the method further includes: determining, according to the destination address carried in the data packet, whether the received data packet belongs to the local base station, and if it belongs to the local base station, the base station is Processing, end this process.

When the upper-level base station determines that the received data packet does not belong to the local-level base station, the forwarding the received data packet includes:

The received data packet is converted into a frame format by the destination address carried in the data packet, and then transmitted to the base station controller on the E1/T1 interface side, or to the lower base station on the Ethernet interface side.

After the method of determining that the received data packet does not belong to the local base station, and before forwarding the received data packet, the method further includes: If the cascading switch is turned on, the step of forwarding the data packet is continued; if the cascading switch is turned off, the received data packet is discarded, and the process ends.

Before the upper base station forwards the data packet, the method further includes: the upper base station successfully acquiring the target base station information.

If the upper base station fails to obtain the destination base station information, the method further includes:

The upper base station sends an address translation protocol ARP packet for acquiring the information of the target base station, and stores the obtained base station information.

A system for implementing base station cascading includes at least a network side, an upper base station, and a lower base station;

The upper base station and the network side are connected by an E1/T1 line, and the upper base station and the lower base station are connected by an Ethernet line;

A cascading processing logic subsystem is configured in the upper base station to uniformly receive data packets and forward the received data packets between different transmission media.

The network side includes a base station controller, or a radio network controller.

The cascading processing logic subsystem includes at least a data interface conversion module, a cascading information maintenance module, a user data exchange module, and a cascade switch module;

The data interface conversion module includes an E1/T1 interface conversion module and an FE interface conversion module: an E1/T1 interface conversion module, configured to convert a downlink data packet frame format at the E1/T1 interface into a frame format of an Ethernet interface; An interface conversion module, configured to convert an uplink data packet frame format at the FE interface into a frame format transmitted by the E1/T1 interface;

A cascading information maintenance module, configured to record and maintain cascading base station parameters;

a user data exchange module, configured to allocate CPU resources to the user, process the service data stream, implement fast hardware switching and network address translation function from the lower base station to the base station controller; and cascade switch module for controlling the cascade function When the cascading switch is turned on, the lower-level base station is connected to the upper-level base station through the FE interface. When the cascading switch is turned off, the upper-level base station accesses the base station controller independently, and does not forward the lower-level cascading data. The cascading information maintenance module is configured to: when the upper base station receives data from the E1/T1 or the FE port, record the base station information carried in the data packet to form a base station information database; or, when the base station information changes , update the database.

The cascading processing logic subsystem further includes an IP header compression module for compressing data packets on the E1/T1 link.

A cascading processing logic subsystem, comprising at least a data interface conversion module, a cascading information maintenance module, a user data exchange module, and a cascade switch module;

a user data exchange module, configured to allocate CPU resources to the user, process the service data stream, implement fast hardware switching and network address translation function from the lower base station to the base station controller; and cascade switch module for controlling the cascade function When the cascading switch is turned on, the lower-level base station is connected to the upper-level base station through the FE interface. When the cascading switch is turned off, the upper-level base station accesses the base station controller independently, and does not forward the lower-level cascading data.

The cascading information maintenance module is configured to: when the upper base station receives data from the E1/T1 or the FE port, record the base station information carried in the data packet to form a base station information database; or, when the base station information changes , update the database.

It can be seen from the solution provided by the present invention that different base stations are used to connect the base station controller and the lower base station on the two sides of the upper base station: the upper base station and the base station controller are connected by the E1/T1 line, and the upper base station and the lower base station are connected. The interface is connected by Ethernet, and the functions of flow control and congestion scheduling are implemented through the cascade processing logic subsystem. In the present invention, the upper base station and the lower base station In the Ethernet networking mode, a port is flexibly connected to multiple lower-level base stations, and bandwidth sharing is realized. The bandwidth is dynamically allocated according to the bandwidth requirements of each lower-level base station, and the bandwidth is not occupied when the base station does not use bandwidth. The other base stations can still use the bandwidth resource. Moreover, the lower-level base station accessing through the Ethernet does not perceive that it accesses the base station controller through the upper-level base station, but considers that it is directly connected to the base station controller. The base station cascading mode of the invention realizes dynamic sharing of bandwidth, reduces cost and improves networking flexibility, and improves the capacity of the cascaded base station. DRAWINGS

FIG. 1 is a schematic diagram of a cascading of a base station according to an implementation scenario of the present invention;

2 is a schematic structural diagram of components of a cascade processing logic subsystem of the present invention; FIG. 3 is a flowchart of data processing at an E1/T1 interface of a higher-level base station of the present invention;

4 is a flow chart of data processing at the FE interface of the upper base station of the present invention. detailed description

In the present invention, the upper base station and the base station controller are connected by an E1/T1 line, and the upper base station and the lower base station are connected by a Fast Ethernet (FE) line; when there is only one lower base station, the upper base station can pass The network cable is directly connected. In the lower-level base station that implements the cascading by using the connection method, the gateway IP address needs to be set as the gateway IP address of the upper-level base station, and the data packet is uniformly received by the upper-level base station.

In the upper base station, the functions of flow control and congestion scheduling are implemented by the cascade processing logic subsystem. The technical solutions of the present invention are further described in detail below with reference to the accompanying drawings and specific embodiments.

In this document, a base station directly connected to a base station controller is referred to as a higher-level base station, and a base station directly connected to the upper-level base station is referred to as a lower-level base station, and all base stations accessing the base station controller in a cascade manner are collectively referred to as a cascaded base station.

FIG. 1 is a schematic diagram of a cascading of a base station according to an implementation scenario of the present invention, as shown in FIG. The base station (such as NodeB1 in FIG. 1) is connected to the base station controller (BSC) or the RNC by using an E1/T1 line, and the interface between the two is an Abis interface or an IUB interface. Specifically, the Abis interface or the IUB interface herein belongs to the physical physical interface, and the link layer protocol of the upper physical port of the entity includes a High Level Data Link Control (HDLC) and a Point-to-Point Protocol (PPP). , Point To Point ), Asynchronous Transfer Mode ( ATM), ATM Inverse Multiplexing (AMA), etc., driven and controlled by the corresponding hardware interface controller and upper protocol stack software module interface . The upper base station (such as NodeB 1 in FIG. 1) and the lower base station (such as NodeB2, NodeB3, and NodeBN in FIG. 1) are connected by an Ethernet line, and the Ethernet interface is connected to a plurality of different lower levels through an IP protocol. Base station. The total egress bandwidth of all cascaded base stations is the bandwidth resource provided by the E1/T1 line between the upper base station and the BSC or RNC. Each base station in the cascading mode of the present invention shares the total used bandwidth. After the physical connection is implemented, as shown in FIG. 1, in the present invention, the transmission between the data of the upper and lower base stations and the base station controller is realized by the control of the cascade processing logic subsystem. The cascading processing logic subsystem can be set in the upper base station, and the communication between the eNB and the base station controller can be realized by corresponding processing of the data by each module.

Referring to FIG. 1 , the present invention further provides a system for implementing base station cascading, which includes at least a network side, an upper base station, and a lower base station;

2 is a schematic structural diagram of each module of the cascading processing logic subsystem of the present invention. As shown in FIG. 2, a cascading logic processing subsystem, an E1/T1 line and a higher-level base station (such as the first stage in FIG. 1) are provided. The format conversion and data frame forwarding between data streams are performed between the Ethernet lines through the cascading processing logic subsystem. As shown in FIG. 2, the cascading processing logic subsystem includes at least a cascading information dimension. a protection module, a user data exchange module, a cascade switch module, and a data interface conversion module including an E1T1 interface conversion module and an FE interface conversion module, wherein:

The data interface conversion module is used to implement transparent data exchange and forwarding, and eliminates the difference between the data frames of the link layer of the E1/T1 and FE transmission media, extracts data, and realizes transparent forwarding between the two interfaces. The E1/T1 interface conversion module and the FE interface conversion module respectively perform data frame format conversion on the two interfaces, specifically; on the E1/T1 interface, the E1/T1 interface conversion module is used in the interface from the E1/T1 interface. When the downlink data packet needs to be transmitted to the lower-level base station, the frame format of the data packet is converted into a frame format that can be transmitted on the Ethernet interface; correspondingly, at the Ethernet interface, the FE interface conversion module is used to be from the lower level. When the uplink data packet of the base station needs to be transmitted to the base station controller, the frame format of the data packet is converted into a frame format that can be transmitted on the E1/T1 interface. The smooth transfer of data can be realized by the function of the data interface conversion module. The cascading information maintenance module is configured to record and maintain related parameters such as the IP address and the MAC address of the cascaded base station. When the upper base station receives data from the E1/T1 line or the FE line each time, the cascading information maintenance module records each The base station information carried in the data packet of the logical subsystem is processed by the cascade to form a base station information database. When the data is normally transmitted, the data received by the cascaded information maintenance module from the E1/T1 or FE port is in the database. The information is compared to determine the destination base station. Further, when the base station related parameters carried in the data packet from the concatenated base station are updated or accessed to the new base station, the information in the base station information database is updated. After the data packet is converted into a frame format by the data interface conversion module, the destination base station information is obtained from the cascading information maintenance module, and the data packet carrying the destination base station information is used to obtain CPU resources through the user data exchange module.

A user data exchange module is configured to allocate CPU resources to the user and process the service data stream. When the upper-level base station obtains the required information from the cascading information maintenance module, the user data notification module is notified, and the user data exchange module allocates resources for the user, and implements fast hardware switching and network address translation from the lower-level base station to the base station controller. When the upper-level base station receives the cascading message (including the packet that the base station controller needs to send to the lower-level base station and the packet sent by the lower-level base station to the upper-level base station), the UDP user plane data is analyzed, and the data is dynamically established according to the user's demand for the bandwidth resource. Forwarding link. At the same time, the system monitors the usage of the resources occupied by the user. After the user UDP data stream is idle for a period of time, the system resources are released, the bearer link resources are deleted, and the resources are dynamically allocated.

A cascade switch module is used to enable or disable the channel of the lower base station to access the upper base station through the Ethernet interface. In order to prevent additional processing load caused by incorrect access of the Ethernet device, the opening or closing of the cascade function is controlled by the cascade switch module. If the cascading switch is turned off, the upper base station is equivalent to the independent access base station controller or RNC, and does not forward the lower cascading data. If the cascading switch is enabled, the cascading function takes effect, and the upper-level base station forwards the lower-level cascading data to the lower-level base station. The opening or closing of the cascade switch is automatically set by the cascade processing logic subsystem. When there is only one lower base station, the upper base station and the lower base station can be directly connected through the network cable. When multiple lower base stations are connected, the lower base station is through the Ethernet. When the interface is connected to the upper-level base station, when the cascade processing logic subsystem is set, the cascade switch is set to be on or off according to the networking mode.

The cascading processing logic subsystem of the present invention further includes an IP header compression module for compressing data packets on the E1/T1 link to improve link utilization.

FIG. 3 is a flowchart of data processing at the upper base station and the E1/T1 interface according to the present invention. As shown in FIG. 3, the method includes the following steps:

Step 301: After receiving the data frame, the E1/T1 interface obtains the data packet, and the cascading information maintenance module compares the destination base station information carried in the data packet with the base station information recorded in the database, and determines whether the destination address of the packet is If the destination address of the packet is the upper-level base station, the packet is delivered to the corresponding upper-level base station for data processing, and the process ends; if the destination address of the packet is the lower-level base station, the process proceeds to step 302.

Step 302: Determine whether the cascading switch is turned on. When the cascading switch is turned on, the packet can be delivered to the cascading base station, and the process proceeds to step 303. When the cascading switch is turned off, the data packet is discarded and is not forwarded. End this process.

Step 303: The upper-level base station acquires related information such as IP and MAC of the target base station from the cascading information maintenance module. In this step,

Because Ethernet needs to learn the MAC address of the destination base station to forward (and E1 is the point) The point-to-point PPP protocol can be directly forwarded. Therefore, it is necessary to modify or replace the network layer forwarding according to the frame format of the data packet that can be received by the interface of the destination base station according to the information about the destination base station recorded by the cascading information maintenance module. Modified IP header format.

In this step, if the destination base station address information is successfully obtained, the process proceeds to step 304. If the information about the destination base station fails to be obtained, the address resolution protocol (ARP) packet is sent through the Ethernet interface to implement the IP address. The mapping with the Ethernet MAC address obtains the destination base station MAC address information. If the ARP response is obtained, the corresponding information is added to the cascading information maintenance module, and the process proceeds to step 304. If the ARP response is not obtained, the packet is discarded and no longer forwarded, and the process ends.

Step 304: Add an Ethernet frame header to the data packet, and send data from the Ethernet interface to the destination base station. In this step, the data interface conversion module converts the packet to be forwarded into a frame format that can be forwarded by the Ethernet interface, and then sends the packet from the Ethernet port to the destination lower-level base station. The specific conversion method is a conventional method for those skilled in the art, and details are not described herein again.

4 is a flow chart of data processing at a higher-level base station and a FE interface according to the present invention. As shown in FIG. 4, the method includes the following steps:

Step 401: After receiving the packet from the lower-level base station, the upper-level base station determines whether the destination IP address is the upper-level base station address, and if yes, passes the packet to the corresponding upper-level base station for processing, and ends the process.

Step 402: Determine whether the cascading switch is turned on when the destination address of the packet does not belong to the base station of the current level. In this step,

When the cascading switch is turned on, the packet can be delivered to the base station controller, and the process proceeds to step 403. When the cascading switch is turned off, the data packet is discarded and is not forwarded, and the process ends.

Step 403: Determine the source base station to which the packet belongs, obtain the IP, MAC address, and other related information of the base station from the cascading information maintenance module, and modify or replace the network layer forwarding according to the frame format of the data packet that the destination base station interface side can receive. The IP header format that needs to be modified. If the acquisition fails, the 4 files are discarded, and the process ends. Step 404: Perform link layer protocol encapsulation on the data packet, and send a data packet from the E1/T1 port. In this step,

The data interface conversion module converts the message to be forwarded into a frame format required for E1/T1 port media transmission and then transmits it to the base station controller or RNC. The specific conversion method is a conventional method for those skilled in the art, and will not be described here.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included. Within the scope of protection of the present invention.

Claims

Claim

The method further includes: the upper base station uniformly receives the data message, and forwards the received data message between different transmission media.

2. The method according to claim 1, wherein the lower base station is one; the lower base station and the upper base station are connected by a network cable.

The method according to claim 2, wherein the method further comprises: setting a gateway IP address of the subordinate base station to a gateway IP address of the superordinate base station to which the base station belongs, and the data packet is uniformly received by the upper base station.

The method according to any one of claims 1 to 3, wherein, after the upper base station receives the data packet, the method further includes: determining, according to the destination address carried by the data packet, the received datagram. Whether the text belongs to the local base station, if it belongs to the local base station, it is processed by the local base station, and the process ends.

The method according to claim 4, wherein, when the upper base station determines that the received data packet does not belong to the local base station, the forwarding the received data message includes:

The method according to claim 5, wherein, after the determining that the received data packet does not belong to the local base station, and before forwarding the received data packet, the method further includes:

It is judged whether the cascading switch is turned on. If the cascading switch is turned on, the step of forwarding the data message is continued; if the cascading switch is turned off, the received data message is discarded, and the process ends.

The method according to claim 6, wherein, before the upper base station forwards the data packet, the method further includes: the upper base station successfully acquiring the target base station information.

8. The method according to claim 7, wherein, if the upper base station fails to acquire the destination base station information, the method further includes:

A system for implementing a cascading of a base station, where at least a network side, an upper base station, and a lower base station are included;

10. The system according to claim 9, wherein the network side comprises a base station controller, or a radio network controller.

The system according to claim 9 or 10, wherein the cascading processing logic subsystem includes at least a data interface conversion module, a cascading information maintenance module, a user data exchange module, and a cascade switch module;

The system according to claim 11, wherein the cascading information maintenance module has The system is configured to record the base station information carried in the data packet to form the base station information database each time the upper base station receives the data from the E1/T1 or the FE port; or, when the base station information changes, update the database.

The system according to claim 11, wherein the cascading processing logic subsystem further comprises an IP header compression module, configured to compress data packets on the E1/T1 link.

14. A cascading processing logic subsystem, wherein: at least a data interface conversion module, a cascading information maintenance module, a user data exchange module, and a cascade switch module;

The cascading processing logic subsystem according to claim 14, wherein the cascading information maintenance module is specifically configured to record a datagram each time the upper base station receives data from the E1/T1 or FE port. The base station information carried in the text forms a base station information database; or, when the base station information changes, the database is updated.

The cascading processing logic subsystem of claim 14, wherein the cascading processing logic subsystem further comprises an IP header compression module for compressing data packets on the E1/T1 link.