WO2003101008A1

WO2003101008A1 - Control and service functionality separated radio access network and method for communication

Info

Publication number: WO2003101008A1
Application number: PCT/CN2003/000083
Authority: WO
Inventors: Ping Zhang
Original assignee: Huawei Technologies Co. Ltd
Priority date: 2002-05-29
Filing date: 2003-01-27
Publication date: 2003-12-04
Also published as: AU2003211830A1; CN1214590C; CN1463128A

Abstract

The present invention relates to control and service functionality separated radio access network and method for communication, and said device includes: radio access server providing access control, radio resource management and mobility control function, radio access gateway providing data transmission function between core network and base station, and base station providing function of controlling users data transmission and performing measurement, transmission of data and controlling information realizes by corresponding interface among every entity. The method is based on said network which comprises : after users information and connection request information from base station are received by radio access server, allocation scheme is determined for said service ; transmission of uplink and downlink data is processed by radio access gateway and base station according to radio resource allocation scheme. The present invention have the advantage of reducing RNC configuration complexity , facilitating introduction of new technique for radio access network, facilitating expanding control function of radio access network and shortening signaling processing time greatly in radio access network, etc.

Description

Wireless access network with separated control and service functions and communication method thereof

The present invention relates to the field of wireless communication technologies, and in particular, to a wireless access network with control and service functions separated and a communication method thereof.

Background technique

At present, the base stations in the wireless access network only communicate with the core network through the RNC (radio network controller), and all control and service functions in the wireless network are concentrated in the RNC. This control and service function is centralized in the wireless access network networking form of the same device. The following problems exist:

(1) The large structure and complicated functions of the RNC have brought great inconvenience to the management and maintenance of the RNC, and the price of the RNC is expensive;

(2) The interface between the RNC and the base station is highly dependent on wireless network communication technology. When new wireless network communication technology is introduced, this excessive combination of RNC and base station functions makes it impossible for a single device in the wireless network. Replacement, that is, two types of equipment must be replaced at the same time to implement the introduction of new technologies. When introducing new technologies, large economic investment is required to update equipment, which brings greater resistance to the introduction of new technologies;

(3) It is very inconvenient to individually expand the control function, and the newly added business function cannot flexibly adapt to the existing control function and business function;

(4) The wireless interface technology suitable for data communication is developing in an adaptive direction, such as adaptive modulation, adaptive feedback, etc. The realization of the adaptive function requires the wireless network to significantly reduce the processing time for signaling. At present, control and service functions Centralized wireless access network structure Unable to adapt to this development need.

Therefore, with the development of wireless network communication technology, a wireless access network form in which control and service functions are concentrated on the same device will not be able to adapt to the new wireless network communication technology. Summary of the Invention

The object of the present invention is to provide a wireless access network and a communication method which are separated from control and service functions, so that the networking form of the wireless access network is more reasonable, so as to meet the requirements of the continuously developing new wireless network communication technology.

The object of the present invention is achieved in such a manner that a radio access network that separates control and service functions is characterized by including:

Wireless access server: implement access control, wireless resource management and mobility control functions fib,

Wireless access gateway: realizes the data conversion and load processing functions between the core network and the access network; that is, the user data transmission function between the core network and the base station;

Base station: control the transmission of user data and perform measurement functions;

The wireless access server, the wireless access gateway and the base station respectively implement data and control information transmission through corresponding interfaces.

The interface includes:

Service transmission interface: located between the wireless access gateway and the core network and between the wireless access gateway and the base station, and is used to transmit user data;

Service control interface: located between the wireless access server and the core network, the wireless access server and the base station wireless access server and the wireless access gateway, and the wireless access server and the wireless access server, and is used to transmit control information; Interfaces between wireless access gateways: located between the wireless access gateways and used to transmit user data and bearer control information;

Interface between base stations: located between base stations and used to transmit user data and control information. The protocol stack of the service transmission interface application includes:

Layer 6: Application layer protocol;

The fifth layer: frame protocol;

Layer 4: Transmission Control Protocol;

The third layer: IP protocol;

Layer 2: link layer protocol;

Layer 1: Physical layer protocol.

The protocol stack applied by the service control interface includes:

The fifth layer: interface application part;

Layer 4: For the interface between the wireless access server and the wireless access gateway, the gateway control protocol is used; for the interface between the wireless access server and the wireless access server, the core network, and the base station, it includes three sublayers, In order: SCCP (Signaling Connection Control Part), M3UA (Type III Media Transmission Protocol User Adaptation Layer), SCTP (Service Control Transmission Protocol);

The third layer: IP protocol;

Layer 2: link layer protocol;

笫 One layer: Physical layer protocol.

The protocol stack of the interface application between the wireless access gateways includes:

Layer 5: Interface application part on the control plane; Frame protocol on the user plane; Layer 4: RTP (Real-time Transport Protocol) on the control plane; Transmission control on the user plane Discuss

The third layer: IP protocol;

Layer 2: link layer protocol;

Layer 1: Physical layer protocol.

The protocol stack of the interface application between the base stations includes:

The fifth layer: the interface application part for the control plane; the frame protocol for the user plane; the fourth layer: the SCCP (signaling connection control part), M3UA (the third type of media transmission protocol user adaptation layer) for the control plane. ), SCTP (Service Control Transmission Protocol); for the user plane is the Transmission Control Protocol;

The third layer: IP protocol;

Layer 2: link layer protocol;

Layer 1: Physical layer protocol.

A communication method for controlling a wireless access network separated from a service function includes:

(1) The base station sends the received user information and connection request information to the wireless access server;

(2) The wireless access server cooperates with the service control server in the core network to determine a scheme for configuring wireless network resources for the service;

(3) The wireless access gateway and the base station only configure the wireless network resource solution determined in step (2) to implement the uplink and downlink data transmission between the core network and the user terminal.

8. The communication method for controlling a wireless access network separated from service functions according to claim 7, characterized in that said step (2) comprises:

(81) The wireless access server establishes a wireless resource control between the base station and the user 制连接； System connection;

(82) sending the user information and the connection request information to a service control server in the core network;

(83) After the service control server in the core network responds to the request, the wireless access server allocates wireless network resources for the service. The specific process is as follows:

(91) The wireless access server sends outer loop power control information and measurement instructions to the base station and the user terminal, and receives the measurement results;

(92) Only adjust the configuration information of the wireless resources according to the processing of the measurement results and the estimated channel quality, and send the configuration information to the base station and the wireless access gateway respectively.

The step (83) further includes a mobility measurement process when the user terminal moves between cells belonging to different base stations under the control of two wireless access servers. The specific steps are:

(101) Two wireless access servers need to exchange information of neighboring base stations and cells, and send mobile measurement requests and receive measurement results to users;

(102) The wireless access server sends the mobility management information to the base stations, and the base stations forward user data and transmission control information related to mobility.

As can be seen from the above technical solution, the present invention adopts a networking structure of a wireless access server, a wireless access gateway, a base station, and a corresponding interface, which realizes the separation of control and service functions in the wireless access network, and enables the base station to communicate with the RNC. The coupling relationship is relatively loose. Therefore, the present invention has the following advantages: A, P contention reduces the complexity of the RNC structure and its cost; B, F It facilitates the introduction of new technologies in the wireless access network and ensures the reasonableness of the input cost when introducing the new technology; C. It is convenient for the expansion of control functions in the wireless access network and the adaptation of new services to existing controls and service functions; D. It can greatly reduce the processing time of the wireless access network to the signaling.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows the structure of a wireless access network with separated control and service functions; Figure 2 shows the protocol stack used by the Iu-u interface and the lug interface;

Figure 3 shows the protocol stack used by the Iu-c, Iur and Iub interfaces;

Figure 4 shows the protocol stack used by the Iuc interface;

Figure 51 and the protocol stack used by the interface;

Figure 6 Protocol stack used by the IuNB interface;

FIG. 7 is a flowchart of a communication method for a radio access network with control and service functions separated. detailed description

The present invention decomposes the current RNC into two entities: control and service. One is responsible for the data transmission between the core network service node and the wireless access network. It is called the wireless access gateway, and the other is responsible for the wireless resources. Entities with functions such as management and mobility management are called wireless access servers. At the same time, some functions related to service transmission that originally belonged to the RNC are moved to the base station, and the base station still controls the wireless transmission with the UE. The functions performed by various entities in a radio access network that separates control and service functions are further described below with reference to FIG. 1:

The wireless access server mainly completes access control, wireless resource management, and mobility control functions. These include: 1. System admission control, congestion control, system information broadcast;

2. Mobility-related functions, including handover, SRNS relocation, paging support and positioning;

3. Control network synchronization and node synchronization;

4. Functions related to radio resource management and control, including:

Configure and activate wireless resources

Wireless environmental investigation (such as processing measurement results, estimating channel quality, etc.)

Establishing and releasing wireless connections

Allocate and release radio bearers

Outer loop power control

Control channel coding scheme and code rate

Random access detection and processing;

5. Broadcast-related information release, flow control and status reporting;

6. Track events related to UE behavior.

The wireless access gateway mainly completes data conversion and load processing between the core network and the access network. These include:

1. Transfer user data between the core network and the base station;

2. Channel encryption and decryption, data integrity protection;

3. Report the flow of UM data to CN;

4. Align with the downlink transmission time between CN nodes;

5. Send the NAS information to the corresponding CN node;

6. Control macro diversity between multiple base stations; T N03 / 00083

-8-

7. Load handling related to mobility;

8. Control the multiplexing of services and users on the RB, segment / reassemble the data, and control the data transmission by using AM or UM.

The function of the base station is to control the transmission of user data and perform measurements, including: 1. Inner loop power control;

2. Wireless channel codec;

3. Wireless environment measurement;

4. Transmission control of user data on multiple cells or multiple physical channels;

5. Multiplexing of different user data on the wireless channel;

6. Control the data transmission in AM or UM mode according to the specified QoS;

7. Measurement node synchronization information;

8. Control transmission channel synchronization and wireless interface synchronization;

9. Control TDD uplink signal synchronization;

10. Mobility-related transmission control.

After the entities with corresponding functions are established, in order to realize the information transmission between the entities, corresponding interfaces need to be established between the entities. As shown in Figure 1, the established interfaces include:

Iu-u interface between wireless access gateway and core network;

Iu-c interface between the wireless access server and the core network;

Lug interface between wireless access gateway and base station;

Iub interface between wireless access server and base station;

IuNB interface between base stations; 03 00083 one 9 one

At the same time, there can be multiple wireless access servers and multiple wireless access gateways in a UTRAN (Universal Terrestrial Access Network). Therefore, it also includes: an Iur interface between two wireless access servers to exchange control information of the wireless access network; an Iuw interface between two wireless access gateways to exchange information related to service transmission. The above interfaces are divided into interfaces for service transmission, interfaces for service control, interfaces between wireless access gateways, and interfaces between base stations according to their completed functions and their locations. Among them: The interfaces used for service transmission include:

Iuu interface: It is used to transmit user data and bearer control information between the wireless access gateway and the media gateway in the core network. Lug interface: A wireless access gateway is connected to one or more base stations through a lug interface. The functions on the lug interface are basically the same as the user plane functions of the lub interface between the RNC and the base station in the current UTRAN (Universal Terrestrial Radio Access Network). The user plane function mainly transmits user data. The protocol stack used by the service transmission interface is shown in Figure 2. The transmission control protocol is a protocol that controls IP transmission on top of the IP protocol layer. The protocol can be connection-oriented or non-connection. The transmission control protocols used by the foregoing interfaces may be the same or different. For example: Transmission Control Protocol can use UDP (User Datagram Protocol), RTP (Real-time Transport Protocol), XTP (Other Transport Protocols), or GRE (General Encapsulation Protocol). Data generated by Transmission Control Protocol can be multiplexed on the same IP data In the report, different data packets of the same user can also be multiplexed in the same IP datagram. Transmission at the IP protocol layer can be implemented based on different link layer protocols. The link layer protocols used by the foregoing interfaces may be the same or different.

Interfaces for business control include:

Iu-c interface: It is used to exchange service control information between the wireless access server and the service control server in the core network.

I ub interface: used to transmit radio resource management / control signaling, access control signaling, mobility management signaling, and broadcast data and signaling between the radio access server and the base station.

lur interface: used to exchange wireless resource management information and mobility support information between wireless access servers.

The Iu-c, lur, and Iub interfaces use similar protocol stacks to the control planes of the Iu, Iub, and lur interfaces in the existing UTRAN structure, respectively. As shown in Figure 3, the transport layer is divided into three sub-layers. They are: SCCP (Signaling Connection Control Part), M3UA (Type III Media Transmission Protocol User Adaptation Layer), SCTP (Service Control Transmission Protocol).

The Iuc interface is located between the radio access server and the radio access gateway, and is used to transmit radio resource management signaling and radio bearer control signaling. The Iuc interface uses an IP-based gateway control protocol. As shown in Figure 4, the protocol used at the transport layer is the gateway control protocol.

The interface between the wireless access gateways is and the interface: transmits user data and bearer control information between the two wireless access gateways. The user data transmission can adopt the RTP / UDP / IP protocol stack, and the bearer control can adopt the RTP or H.245 protocol, as shown in Figure 5.

The interface between the base stations is the IuNB interface: used to transfer user data between the two base stations PT / CN03 / 00083

-11- and transmission control information. The protocol stack used by the IuNB interface is shown in Figure 6. The control plane transmission layer is divided into three sub-layers. The protocols used are: SCCP (Signaling Connection Control Part), M3UA (Tertiary Media, Physical Transmission Protocol User Adaptation Layer) ), SCTP (Service Control Transmission Protocol). A radio access network entity with corresponding functions and an interface between the entities are established, and a radio access network with separation of control and service functions is established. The following describes a control and establishment of a data service based on the above with reference to FIG. The process of transmission in the UTRAN structure with separated service functions: First, in the service access process, it is assumed that the service is a service initiated by a user terminal. Step 1: The base station receives the service connection request from the user terminal through the wireless interface; Step 2: The base station sends the user identification and connection request information to the wireless access server through the Iub interface; Step 3: The wireless access server uses the system's current resource usage The status determines whether the service can be accessed; if it can, go to step 4, otherwise go to step ⁵ ; Step 4: The wireless access server establishes a wireless resource control connection with the user terminal through the Iub interface and the wireless interface; and The user identification and service request information of the user are sent to the service control server in the core network through the Iu-c interface, and step 6 is performed; step 5: the access process is ended. Step 6: Receive service response or rejection information from the service control server. If the core network responds to the access of the service, go to step 7; otherwise, go to step ⁵ ; Step 7: The wireless access server notifies via the Iub interface and the wireless interface The user terminal performs step 8 to start the configuration of wireless resources. Step 8: The wireless access server receives the current service from the core network through the Iu-c interface. The radio access bearer information that should be used;

Step 9: Based on the wireless resource usage status in the current system, determine the wireless resource allocation scheme that the current service should use, and notify the base station and the wireless access gateway of the content of the scheme through the Iub interface and Iuc interface, respectively;

Step 10: The base station and the wireless access gateway perform radio bearer allocation according to the specified radio resource allocation scheme. Then, step 11 is performed to start service transmission.

Step 11: First of all, for service transmission, time alignment, transmission channel synchronization, and wireless interface synchronization are required for the Iu-u interface, the lug interface, and the wireless interface.

Step 12: Perform uplink and downlink user data transmission between the Iu-u interface and the wireless interface through the wireless access gateway and the base station;

In the process of service transmission, the wireless access server also sends out-loop power control information and measurement instructions to the base station and user terminals through the Iub interface and the wireless interface; and receives the measurement results from the Iub interface; The estimated channel quality adjusts the configuration status of the wireless resources; and then sends the reconfigured wireless resource information to the base station and the wireless access gateway through the Iub interface and Iuc interface, respectively, so that the base station and the wireless access gateway can receive new The radio resource configuration information is to adjust the radio resource configuration of the user terminal.

When a user moves between cells that belong to different base stations under the control of two wireless access servers, the wireless access server exchanges information of neighboring base stations and cells through the Iur interface, and sends the mobile to the user through the Iub interface and the wireless interface. The measurement request and the measurement result are received; the wireless access server sends the mobility management information to the base station through the Iub interface, and the base stations forward the users related to mobility through the IuNB interface or Iub and Iur interfaces Data and transmission control information; In the case of SRNS (Serving Wireless Network System) relocation, in addition to the mobility-related information that needs to be forwarded between base stations, the wireless access servers also need to pass the service with the user through the Iur interface. For control related information, the wireless access gateways connected to the two wireless access servers may also forward the user's business data and bearer information through 1 and the interface.

When the service is terminated, the wireless access server releases all wireless resources related to the service and sends service termination confirmation information to the user terminal and the core network.

After the above process, a data service can be transmitted in a wireless access network with separated control and service functions provided by the present invention, which further illustrates that communication between user terminals based on a wireless access network with separated control and service functions becomes possible, that is, this The implementation and application of a wireless access network that has the advantages of high data transmission rate, reasonable networking form, and control and separation of business functions have become possible.

Claims

Rights request

1. A wireless access network with separated control and service functions, comprising: a wireless access server: implementing access control, wireless resource management, and mobility control functions;

2. The wireless access network with separated control and service functions according to claim 1, wherein the interface comprises:

Service control interface: It is located between the wireless access server and the core network, the wireless access server and the base station wireless access server and the wireless access gateway, and the wireless access server and the wireless access server, and is used to transmit control information;

Interfaces between wireless access gateways: located between the wireless access gateways and used to transmit user data and bearer control information;

Interface between base stations: located between base stations and used to transmit user data and control information. 3. The wireless access network with separated control and service functions according to claim 2, wherein the protocol stack applied by the service transmission interface comprises:

Layer 6: Application layer protocol; The fifth layer: frame protocol;

Layer 4: Transmission Control Protocol;

The third layer: IP protocol;

Layer 2: link layer protocol;

Layer 1: Physical layer protocol.

4. The wireless access network for controlling and separating service functions according to claim 2, wherein the protocol stack applied by the service control interface comprises:

The fifth layer: interface application part;

Layer 4: For the interface between the wireless access server and the wireless access gateway, the gateway control protocol is used; for the interface between the wireless access server and the wireless access server, the core network, and the base station, it includes three sublayers. In order: SCCP (Signaling Connection Control Part), M3UA (Type III Media Transmission Protocol User Adaptation Layer), SCTP (Service Control Transmission Protocol); Layer 3: IP Protocol;

Layer 2: link layer protocol;

Layer 1: Physical layer protocol.

5. The wireless access network with separated control and service functions according to claim 2, characterized in that the protocol stack of the interface application between the wireless access gateways comprises: Layer 5: Interface application on the control plane Part; Frame protocol on the user plane; Layer 4: RTP (Real-time Transmission Protocol) on the control plane: Transmission control protocol on the user plane;

The third layer: IP protocol;

Layer 2: link layer protocol; Layer 1: Physical layer protocol.

6. The wireless access network with separated control and service functions according to claim 2, characterized in that the protocol stack of the interface application between the base stations comprises:

The fifth layer: the interface application part for the control plane; the frame protocol for the user plane; the fourth layer: SCCP (signaling connection control part) for the control plane, M3UA

(Third type of media transmission protocol user adaptation layer), SCTP (Service Control Transmission Protocol); For the user plane, it is a transmission control protocol;

The third layer: IP protocol;

Layer 2: link layer protocol;

Layer 1: Physical layer protocol.

7. A communication method for controlling a wireless access network separated from service functions, comprising: (1) the base station sends the received user information and connection request information to the wireless access server;

(81) The wireless access server establishes a wireless resource control connection between the base station and the user;

(82) Send the user information and connection request information to the service control in the core network Server:

(83) After the service control server in the core network responds to the request, the wireless access server allocates wireless network resources for the service.

9. The communication method for controlling a wireless access network separated from service functions according to claim 8, wherein said step (83) further comprises adjusting wireless network resource configuration information during service transmission, The specific process is:

(92) Adjust the configuration information of the wireless resources according to the processing of the measurement result and the estimated channel quality, and send the configuration information to the base station and the wireless access gateway respectively.

10. The communication method for controlling a wireless access network separated from service functions according to claim 8, wherein said step (83) further comprises when the user terminal is controlled by two wireless access servers. The process of determining mobility when moving between cells of different base stations is as follows: