CN109922538B

CN109922538B - Method and system for supporting RAN (radio access network) -assisted WLAN (Wireless local area network) interconnection by RN (radio network)

Info

Publication number: CN109922538B
Application number: CN201711317495.0A
Authority: CN
Inventors: 魏立梅; 袁乃华; 范晨; 朱玉梅; 孔胜淼; 汪振东
Original assignee: Chengdu TD Tech Ltd
Current assignee: Chengdu TD Tech Ltd
Priority date: 2017-12-12
Filing date: 2017-12-12
Publication date: 2020-09-25
Anticipated expiration: 2037-12-12
Also published as: CN109922538A

Abstract

The application discloses a method for supporting RAN-assisted WLAN (Wireless local area network) interconnection by RN (radio network), which comprises the following steps in the RN starting process: the RN reports WLAN interconnection capacity supporting RAN assistance to the DeNB; the DeNB selects one of all RN subframe configuration modes including the newly-added RN subframe configuration mode, and configures the RN subframe configuration mode to the RN through the RN reconfiguration message; the RN sets an uplink subframe and a downlink subframe of a Un interface according to an RN subframe configuration mode in the RN reconfiguration message; configuring a candidate WLAN list and a RAN auxiliary parameter list for the RN by an OAM system of the DeNB or the RN; and the RN saves the WLAN list and the RAN auxiliary parameter list. The application also discloses a system for supporting WLAN interconnection assisted by RAN by the RN. By applying the technical scheme disclosed by the application, the loads of the Uu interface and the Un interface can be reduced, and the risk of congestion of the Uu interface and the Un interface is reduced.

Description

Method and system for supporting RAN (radio access network) -assisted WLAN (Wireless local area network) interconnection by RN (radio network)

Technical Field

The present application relates to the field of communications technologies, and in particular, to a method and a system for supporting RAN-assisted WLAN interworking by an RN.

Background

Currently, 3GPP protocols support Radio Access Network (RAN) assisted WLAN interworking. There are two ways for RAN-assisted WLAN interworking, specifically as follows:

(1) WLAN interworking with traffic steering rules based on access network selection defined in 3GPP TS36.304 protocol: in this manner, the UE determines the direction of traffic steering between the E-UTRAN and the WLAN based on the access network selection and traffic steering rules defined in the 3GPP TS36.304 protocol.

(2) WLAN interconnection based on Access Network Discovery and Selection Function (ANDSF) strategy in 3GPP TS24.312 protocol: in this way, the UE determines the direction of traffic diversion between E-UTRAN and WLAN based on ANDSF policies in the 3gpp ts24.312 protocol.

The UE indicates to the network whether RAN-assisted WLAN interworking is supported, and the way of WLAN interworking is specifically supported, through the following capability reports.

(1) wlan-IW-RAN-Rules-r 12: the UE indicates by this parameter: whether WLAN interworking with traffic steering rules based on access network selection defined in the 3GPP TS36.304 protocol is supported. The UE supporting the WLAN interworking mode supports obtaining RAN assistance parameters required by the corresponding rule through system messages or dedicated signaling.

(2) wlan-IW-ANDSF-Policies-r 12: the UE indicates by this parameter: whether to support WLAN interworking based on ANDSF policy in the 3gpp ts24.312 protocol. The UE supporting the WLAN interworking mode supports obtaining RAN assistance parameters required by a corresponding policy through system messages or dedicated signaling.

RAN-assisted WLAN interworking is applied to UEs in RRC _ IDLE (RRC CONNECTED) state or UEs that are in RRC _ CONNECTED (RRC CONNECTED) state but are not configured by eNB with RCLWI (RAN Controlled LTE-WLAN interworking, LTE and WLAN interworking) information, LWA (LTE-WLAN Aggregation, LTE and WLAN Aggregation) information, and LWIP (LTE WLAN Radio Level Integration with IPsec Tunnel, Radio Level Integration of LTE and WLAN based on IPsec Tunnel) information. Here, the eNB does not configure the RCLWI information, LWA information, and LWIP information to the UE, indicating that: the eNB does not initiate the RCLWI, LWA, and LWIP functions of the UE. RCLWI, LWA, LWIP, and RAN assisted WLAN interworking are four ways for LTE systems to utilize WLAN resource offload traffic. The four modes have characteristics and corresponding application scenes respectively. Typically, the eNB will only initiate one of these four modes. The special characteristics are that: the UE performs only the RCLWI function when both RCLWI and RAN assisted WLAN interworking are simultaneously enabled. If the UE supports RAN-assisted WLAN interworking, the UE may determine whether to transmit traffic over WLAN or LTE in the current wireless environment based on the supported WLAN offloading criteria or policies, the RAN-assisted parameters of the network configuration, and the related measurement results.

The UE supporting RAN-assisted WLAN interworking obtains RAN-assisted parameters from the eNB in two ways:

(1) obtaining common RAN assistance parameters via system messages: the eNB broadcasts the traffic steering information between the E-UTRAN and the WLAN through SIB17, which specifically includes: WLAN ID list and WLAN offload information IE (information element). The WLAN ID list is the ID list of WLAN APs (WLAN access points) in the coverage area of the current eNB. The WLAN offload information IE provides a common RAN-assisted parameter list. Individual RAN assistance parameters are provided in the IE in an "optional" manner, which may be a summary of RAN assistance parameters needed for both RAN-assisted WLAN interworking manners.

(2) Obtaining proprietary RAN assistance parameters through dedicated signaling: and the eNB configures the WLAN offload indication for the UE through the RRC connection reconfiguration message. The value of the WLAN offload indication is: released or established. When the value of the offloading indication is establishment, the eNB also configures, through an RRC connection reconfiguration message, the value of the WLAN offloading information IE and the timer t350 to the UE. Here, the WLAN offload information IE is as above. The eNB can know whether the UE supports the WLAN interconnection assisted by the RAN and which WLAN interconnection mode is supported according to the reporting of the capability of the UE when the UE accesses the network. For the UE supporting WLAN interconnection, the eNB only configures the RAN auxiliary parameters required in the corresponding mode to the UE through the WLAN shunt information IE according to the WLAN interconnection mode supported by the UE; for RAN auxiliary parameters required by WLAN interworking mode not supported by the UE, it is not necessary to configure the RAN auxiliary parameters to the UE through the WLAN offloading information IE.

For the UE:

if the value of the WLAN offload indication obtained by the UE through the RRC connection reconfiguration message is "release," the UE performs the following operations:

(1) releasing the previously received WLAN offload information IE and the timer t 350;

(2) if the SIB17 has WLAN offload information IE, applying RAN auxiliary parameters given by the IE;

otherwise, the UE applies the RAN assistance parameter given by the WLAN offloading information IE obtained by the RRC connection reconfiguration message.

And the UE in the following state performs WLAN offload evaluation according to the RAN auxiliary parameters obtained by the method and the supported WLAN interconnection modes:

(1) UE is in RRC _ IDLE

(2) The UE is in RRC _ CONNECTED, but is not configured with RCLWI information, LWA information, and LWIP information by the eNB, i.e.: the eNB does not turn on RCLWI, LWA and LWIP functions of the UE

The WLAN offload evaluation process of the UE is as follows: the UE determines whether to transmit the service through the WLAN or the LTE according to a measurement result of each WLAN in a WLAN Mobility Set (WLAN mobile Set), a measurement result of the UE on a current access cell or a camped cell, RAN auxiliary parameters in a WLAN offloading information IE, and an offloading criterion or policy corresponding to a WLAN interworking mode supported by the UE. Here, if the eNB configured the RCLWI information to the UE before, the UE uses the WLAN Mobility Set configured to the UE in the RCLWI information as the WLAN Mobility Set in the WLAN offloading evaluation; if the UE has not configured WLAN Mobility Set before, the UE uses the WLAN ID list in SIB17 as WLAN Mobility Set in WLAN offloading evaluation. The measurement result of the UE for each WLAN includes: the channel utilization of the WLAN (to reflect the loading condition of the WLAN), the UL bandwidth and DL bandwidth that the WLAN can provide, and the Reference Signal Strength Indication (RSSI) of the WLAN. The measurement result of the UE on the current access cell or the camping cell includes: RSRP or RSRQ (reference signal received power and reference signal received quality, respectively).

The detailed descriptions of the criteria or policies based on different WLAN interworking modes are referred to as related protocols, and are not described herein again.

For the UE supporting RAN-assisted WLAN interconnection, when the UE finds that the condition of transmitting the service through the WLAN is met through measurement, the UE can directly access the WLAN and transmits the service through the WLAN without occupying LTE resources. When the UE is in a blind spot or a boundary covered by the WLAN and finds that the condition of transmitting through the LTE is met, the UE can divert the service transmitted through the WLAN to the LTE and apply for resources to the LTE to transmit the corresponding service so as to improve service experience.

RAN assisted WLAN interworking allows the eNB to offload some traffic to the WLAN, mitigating LTE air interface load. However, at present, Relay Nodes (RNs) in 3GPP protocols do not support RAN-assisted WLAN interworking, and therefore RNs cannot offload traffic to WLANs through this function. Since the Uu interface and the Un interface of the RN share the resources of all the uplink subframes and the resources of the downlink subframes, the UL/DL resources of the Uu interface of the RN are limited by the splitting function of the Un interface, compared with the Uu interface of the eNB. If the RN supports the WLAN interconnection function assisted by the RAN, some services can be shunted to the WLAN, the UL/DL load of the Uu interface is effectively relieved, and the risk of congestion of the Uu interface is reduced. Moreover, the traffic distributed to the WLAN does not transit through the Un interface, and the load and congestion risk of the Un interface can be effectively reduced.

Disclosure of Invention

The application provides a method and a system for supporting RAN-assisted WLAN interconnection by RN, so as to realize the support of the RN on the RAN-assisted WLAN interconnection, thereby reducing the load of a Uu interface and a Un interface and reducing the risk of congestion of the Uu interface and the Un interface.

The application discloses a method for supporting Wireless Local Area Network (WLAN) interconnection assisted by Radio Access Network (RAN) by Relay Node (RN), which comprises the following operations in the process of starting the RN:

the RN reports WLAN interconnection capacity supporting RAN assistance to a donor base station DeNB;

the DeNB selects a configuration mode from all RN subframe configuration modes including a newly-added RN subframe configuration mode, and configures the configuration mode to the RN supporting the WLAN interconnection assisted by the RAN through an RN reconfiguration message;

the RN sets an uplink subframe and a downlink subframe of a Un interface according to an RN subframe configuration mode in the RN reconfiguration message;

an operation, maintenance and administration (OAM) system of the DeNB or the RN configures a candidate WLAN list and a RAN auxiliary parameter list for the RN supporting RAN auxiliary WLAN interconnection;

the RN takes the candidate WLAN list as a WLAN ID list in a system information block SIB17, takes the RAN auxiliary parameter list as a RAN auxiliary parameter list provided by WLAN offload information IE in SIB17, and saves the WLAN list and the RAN auxiliary parameter list.

Preferably, when the DeNB configures a candidate WLAN list and a RAN assistance parameter list for an RN supporting RAN assisted WLAN interworking, the method further comprises: the DeNB carries the candidate WLAN list and the RAN auxiliary parameter list in the RN reconfiguration message and sends the RN;

when the RN supporting RAN-assisted WLAN interworking is configured with a candidate WLAN list and a RAN-assisted parameter list by an OAM system of the RN, the method further comprises: and the RN reports the WLAN interconnection capacity supporting the RAN assistance to an OAM system of the RN, and after receiving the capacity report of the RN, the OAM system supporting the RAN assistance WLAN interconnection executes the operation of configuring a candidate WLAN list and a RAN assistance parameter list for the RN supporting the RAN assistance WLAN interconnection.

Preferably, after the RN start-up procedure, the method further includes:

the RN sends SIB17, wherein the SIB17 carries configuration information of the split between the E-UTRAN and the WLAN, and the configuration information comprises: a list of WLAN IDs and a list of RAN assistance parameters.

Preferably, after the RN start-up procedure, the method further includes:

for the UE in a radio resource control CONNECTED state RRC _ CONNECTED and reporting a supported RAN-assisted WLAN interconnection mode, if the capability information reported by the UE indicates that the UE supports at least one function of convergence LWA of LTE and WLAN, interconnection RCLWI of LTE and WLAN controlled by RAN and wireless level integration LWIP of LTE and WLAN based on IPsec tunnel, and the RN determines not to configure LWA, RCLWI or LWIP information for the UE, the RN configures WLAN measurement for the UE and reports WLAN configuration WLAN Mobility Set to the UE based on the WLAN measurement of the UE.

Preferably, after the RN start-up procedure, the method further includes:

for the UE which is in RRC _ CONNECTED state and reports the supported RAN-assisted WLAN interconnection mode, if the capability information reported by the UE indicates that the UE supports at least one function of LWA, RCLWI and LWIP, and the RN determines not to configure the LWA, RCLWI or LWIP information for the UE, the RN configures a special RAN-assisted parameter list for the UE.

Preferably, the RN determines a UE-specific RAN assistance parameter list based on RAN assistance parameter list decision information, the RAN assistance parameter list decision information comprising at least one of:

the uplink load condition and/or the downlink load condition of the current RN at the Uu interface and the Un interface;

the service quality QOS information of the EPS bearing of the existing evolution grouping system of the UE;

and (4) load measurement results of each WLAN in the coverage area of the RN.

Preferably, when the RAN assistance parameter list decision information includes the load measurement result of each WLAN in the coverage area of the RN, the RN further performs the following processing:

the RN establishes connection with the WLANs in the candidate WLAN list in sequence; wherein, if N1 WLANs are associated with the same WT, RN establishes Xw interface connection directly with the WLAN termination node WT, but not with each WLAN on which the WT hangs down; if N2 WLANs are hung on the same SeGW, the RN directly establishes Xw interface connection with the security gateway SeGW, but does not directly establish connection with each WLAN hung under the SeGW; wherein, N1 and N2 are natural numbers;

and the RN sends a WLAN load measurement request message through an Xw interface, instructs each WLAN hung under the WT or the SeGW to execute WLAN load measurement, and receives WLAN load measurement reports of each WLAN through the Xw interface.

Preferably, the newly added RN subframe configuration mode at least includes a newly added RN subframe configuration mode;

any one of the newly-added RN subframe configuration modes is used for configuring more uplink subframes or downlink subframes than the existing RN subframe configuration mode to the Un interface.

Preferably, the candidate WLAN list is an ID list of WLAN access points APs in a coverage area of a cell controlled by the RN;

the RAN auxiliary parameter list is a list formed by values of the RAN auxiliary parameters broadcasted in the SIB 17.

The application also discloses a system for supporting RAN-assisted WLAN interconnection by RN, which comprises the following operations in the process of starting RN:

the RN reports WLAN interconnection capacity supporting RAN assistance to the DeNB;

configuring a candidate WLAN list and a RAN auxiliary parameter list for the RN supporting the RAN auxiliary WLAN interconnection by an OAM system of the DeNB or the RN;

the RN takes the candidate WLAN list as a WLAN ID list in SIB17, takes the RAN auxiliary parameter list as a RAN auxiliary parameter list provided by the WLAN offload information IE in SIB17, and saves the WLAN list and the RAN auxiliary parameter list.

According to the technical scheme, the method and the system for supporting RAN-assisted WLAN interconnection by the RN have the advantages that the RN supports RAN-assisted WLAN interconnection, the load of the Uu interface and the Un interface is reduced, and the risk of congestion of the Uu interface and the Un interface is reduced.

Drawings

FIG. 1 is a schematic diagram of an RN architecture;

fig. 2 is a diagram of an RN architecture for supporting RAN-assisted WLAN interworking in accordance with the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is further described in detail below by referring to the accompanying drawings and examples.

The architecture of the RN is shown in fig. 1. The RN cannot transmit or receive data at the Uu interface and the Un interface at the same time, and therefore, the Uu interface and the Un interface time-division multiplex uplink/downlink subframes: both interfaces use uplink subframes to transmit data and both use downlink subframes to receive data. The Donor base station (DeNB: Donor eNodeB) configures RN subframe configuration mode for RN, and indicates which downlink subframes are used for transmitting from DeNB-to-RN (DeNB to RN) and which uplink subframes are used for transmitting from RN-to-DeNB (RN to DeNB). According to the different types of data transmitted on the Un interface, two logical interfaces can be defined on the Un interface: an S1 interface and an X2 interface, the DeNB forwards S1 information between the RN and the EPC through a logical interface S1, and the DeNB forwards X2 information between the RN and other eNodeBs through a logical interface X2.

In the invention, the RN is added with the WLAN interconnection function assisted by the RAN, so that the RN can provide public WLAN shunt information or special WLAN shunt information for the UE, and support an added RN subframe configuration mode to configure more uplink subframes or downlink subframes for the Un. Specifically, the RAN-assisted WLAN interworking function newly added to the RN includes the following:

(1) and (3) the RN reports to the DeNB: the ability to support RAN-assisted WLAN interworking;

(2) the RN supports a newly-added RN subframe configuration mode and supports more uplink subframes or downlink subframes to be allocated to the Un interface for use;

(3) adding operation of acquiring a candidate WLAN list from OAM or DeNB of the RN by the RN;

(4) for the UE which is in RRC _ CONNECTED state and supports the WLAN interconnection capability assisted by RAN, the RN adds the operation of configuring the special WLAN shunt information for the UE;

(5) the operation of the RN to add a new SIB17 to broadcast common RAN assistance parameters within the cell includes: public WLAN mobility Set and public WLAN offload information;

(6) and configuring the special WLAN shunt information for the UE, adding the operation of configuring the WLAN measurement for the UE by the RN, and configuring the WLAN Mobility Set and the special WLAN shunt information for the UE according to the WLAN measurement report of the UE and other related information.

If the off-hook RN supports the RAN-assisted WLAN interworking function, the corresponding DeNB needs to add the following functions:

(1) and (3) reporting the capacity of receiving the RN: the ability to support RAN-assisted WLAN interworking;

(2) supporting the newly added RN subframe configuration mode, configuring the newly added RN subframe configuration mode for the RN supporting the WLAN interconnection assisted by the RAN, and allocating more uplink/downlink subframes to the Un interface.

For RNs supporting RAN-assisted WLAN interworking, which either broadcast SIB17 or configure proprietary RAN assistance parameters to UEs at RRC _ CONNECTED and supporting RAN-assisted WLAN interworking functions, the RN needs to know the following information:

(1) list of WLAN IDs in SIB 17: the list should be made up of the IDs of the WLAN APs within the coverage area of the RN. This list may be configured to the RN by the DeNB or the RN's OAM system during the RN startup procedure.

(2) Values of the common RAN assistance parameters broadcast in SIB 17: the values of the public RAN auxiliary parameters can be determined in advance by an OAM system of the DeNB or the RN according to the coverage condition of the WLAN in the coverage area of the RN and the network planning condition of the cell controlled by the RN, and the OAM system of the DeNB or the RN is configured to the RN when the RN is started.

(3) For a UE in RRC _ CONNECTED and supporting RAN-assisted WLAN interworking, the RN needs to determine the value of a RAN-assisted parameter specific to the UE. The RN may add a new method for determining the dedicated RAN auxiliary parameter to determine the value of the dedicated RAN auxiliary parameter for such a UE. The inputs to the method include many or all of the following, of course without limitation to the following information. The output of the method is: UE-specific RAN assistance parameter values.

(3-1) UL/DL load conditions of the current RN at the Uu interface and the Un interface;

(3-2) QOS information of the existing EPS bearer of the UE;

and (3-3) measuring the load of each WLAN in the coverage area of the RN.

(4) For a UE in RRC _ CONNECTED and supporting RAN-assisted WLAN interworking, if the UE has WLAN measurement capability and supports WLAN Mobility Set configuration, the RN may further add a WLAN measurement configuration to the UE, and report that a dedicated WLAN Mobility Set is configured for the UE through the WLAN measurement of the UE.

If the UE indicates support of LWA, RCLWI or LWIP in the report of the capability information, the RN determines: the UE supports WLAN measurements and supports configuring WLAN Mobility Set. When the UE has LWA, RCLWI, or LWIP capabilities but the RN does not start the corresponding functions, the RN may borrow the functions of supporting WLAN measurement and measurement reporting, which are brought to the UE by the corresponding capabilities, configure WLAN measurement for the UE, determine WLAN Mobility Set based on the WLAN measurement report of the UE, and may configure the WLAN Mobility Set to the UE by using the IE of configuring LWA information, RCLWI information, or LWIP information for the UE in RRC connection reconfiguration.

(5) When the method for configuring the UE with the dedicated RAN auxiliary parameters requires the auxiliary measurement results of each WLAN in the RN coverage area, the RN may establish an Xw interface with the WLAN APs in the candidate WLAN list, configure load measurement for the WLAN APs through the interface, and receive the load measurement result report of the WLAN APs through the interface.

The method for supporting RAN-assisted WLAN interconnection by RN provided by the invention specifically comprises the following steps:

in the process of RN starting, the RN supporting RAN-assisted WLAN interconnection, the DeNB hanging the RN with the RAN-assisted WLAN interconnection capability and the OAM system of the RN realize the support of RAN-assisted WLAN interconnection according to the following methods:

(1) and (3) the RN reports to the DeNB: RAN assisted WLAN interworking capability is supported.

(2) And the DeNB selects one configuration mode from all RN subframe configuration modes including the newly-added RN subframe configuration mode, and configures the configuration mode to the RN supporting the RAN-assisted WLAN interconnection capability through the RN reconfiguration message. Wherein, the newly added RN subframe configuration mode at least comprises a newly added RN subframe configuration mode. Any one of the newly-added RN subframe configuration modes can configure more uplink subframes or downlink subframes to the Un interface so as to improve the uplink or downlink capacity of the Un interface.

(3) And the RN sets an uplink subframe and a downlink subframe of the Un interface according to the RN subframe configuration mode in the RN reconfiguration message. And under the configuration mode that the configuration mode is the newly added RN subframe configuration mode, the RN supports more uplink subframes or downlink subframes to be allocated to the Un interface.

(4) The OAM system of the DeNB or RN configures a list of candidate WLANs and a list of RAN assistance parameters to RNs supporting RAN assisted WLAN interworking.

The candidate WLAN list is the ID list of WLAN APs in the coverage area of the cell controlled by the RN. The RAN assistance parameter list is a list of values of the RAN assistance parameters broadcasted in the SIB 17.

When the candidate WLAN list and the RAN auxiliary parameter list are configured to the RN by the DeNB, the candidate WLAN list and the RAN auxiliary parameter list are carried to the RN together with the RN subframe configuration mode through an RN reconfiguration message.

When an OAM system of the RN configures a candidate WLAN list and a RAN auxiliary parameter list for the RN, the RN reports to the OAM system of the RN firstly in the starting process: RAN assisted WLAN interworking capability is supported. For an OAM system supporting RAN-assisted WLAN interconnection, after receiving the capability report of the RN, configuring a candidate WLAN list and a RAN auxiliary parameter list for the RN.

(5) The RN uses the candidate WLAN list as the WLAN ID list in SIB17, uses the RAN auxiliary parameter list as the RAN auxiliary parameter list provided by the WLAN offloading information IE in SIB17, and saves the two lists.

After the RN starting process, the RN sends SIB17, SIB17 carries configuration information for forking between E-UTRAN and WLAN common to cells, and the configuration information comprises: a list of WLAN IDs and a list of RAN assistance parameters.

After the RN starts the procedure, for a UE in RRC _ CONNECTED and reporting the supported RAN-assisted WLAN interworking mode, if the capability information reported by the UE indicates that the UE supports at least one of LWA, RCLWI, and LWIP, if the RN decides not to configure the LWA, RCLWI, or LWIP information for the UE, preferably, in order to make the UE perform the RAN-assisted WLAN offloading function better, the RN may configure the UE with WLAN measurement and report the UE with WLAN mobility Set based on the WLAN measurement of the UE. The WLAN Mobility Set configured for the UE is carried to the UE through an RRC connection reconfiguration message. The method for configuring the WLAN measurement for the UE is the existing method of the 3GPP protocol, and is not described again. The method for determining WLAN mobility Set according to WLAN measurement report of UE is a specific implementation method, and is not described in detail.

After the RN starts a procedure, for a UE in RRC _ CONNECTED and reporting a supported RAN-assisted WLAN interworking mode, if the capability information reported by the UE indicates that the UE supports at least one of LWA, RCLWI, and LWIP, and if the RN determines not to configure LWA, RCLWI, or LWIP information for the UE, the RN configures a dedicated RAN-assisted parameter list for the UE so that the UE better performs the RAN-assisted WLAN offloading function. In particular, the RN may determine a UE-specific RAN assistance parameter list based on the RAN assistance parameter list decision information. The RAN assistance parameter list decision information includes one or more of the following information, but is not limited to the following information.

(1) The UL/DL load condition of the current RN at the Uu interface and the Un interface;

(2) QOS information of the existing EPS bearer of the UE;

(3) and (4) load measurement results of each WLAN in the coverage area of the RN.

When the RAN assistance parameter list decision information includes the load measurement results of each WLAN in the RN coverage area, after the RN start-up procedure, the RN needs to perform the following processing:

(1) and the RN establishes connection with the WLANs in the candidate WLAN list in turn. Specifically, if several WLANs are associated with the same WT (WLAN Termination Point) (similar to the case in LWA or RCLWI), the RN establishes an Xw interface connection directly with the WT, without establishing a connection directly with each WLAN on which the WT hangs. If several WLANs are hooked up to the same SeGW (Security Gateway) (similar to the case in LWIP), the RN directly establishes an Xw interface connection with the SeGW, and does not need to directly establish a connection with each WLAN hooked up to the SeGW. When some WLANs are co-sited with the RN, the RN may directly connect with each such WLAN through an internal interface, which is not defined, but the internal interface performs the same function as the Xw interface. The process of establishing the Xw interface connection with the WT or SeGW may adopt a method defined in the 3GPP TS36.463 protocol, and is not described in detail.

(2) And the RN sends a WLAN load measurement request message through an Xw interface, indicates to carry out WLAN load measurement and receives a WLAN load measurement report through the interface. Specifically, the process in which the RN sends the WLAN load measurement request to the WT or SeGW through the Xw interface, and the process in which the RN receives the WLAN load measurement report from the WT or SeGW through the Xw interface refer to related processes in the 3GPP TS36.463 protocol, which are not described herein again. When the RN and the WLAN are interconnected through the internal interface, the RN sends a WLAN load measurement request message to the corresponding WLAN through the internal interface, instructs the corresponding WLAN to carry out WLAN load measurement, and receives a WLAN load measurement report of the corresponding WLAN through the internal interface. The related processes executed through the internal interface and the related processes executed through the Xw interface are not described again.

The architecture of the RN supporting RAN assisted WLAN interworking of the present invention is shown in fig. 2. When supporting the RAN-assisted WLAN interworking function, the RN in the figure supports initiating a WLAN load measurement request through an Xw interface, and supports obtaining a WLAN load measurement report from a WT or a SeGW through the Xw interface. WLAN-based assisted measurement reporting and other related information configures a proprietary RAN-assisted parameter list to UEs supporting RAN-assisted WLAN interworking and at RRC _ CONNECTED.

The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A method for supporting wireless access network (RAN) assisted Wireless Local Area Network (WLAN) interconnection by a Relay Node (RN) is characterized by comprising the following operations in the RN starting process:

the RN takes the candidate WLAN list as a WLAN ID list in a system information block SIB17, takes the RAN auxiliary parameter list as a RAN auxiliary parameter list provided by WLAN offload information IE in SIB17, and saves the candidate WLAN list and the RAN auxiliary parameter list.

2. The method of claim 1, wherein:

when the candidate WLAN list and the RAN assistance parameter list are configured by the DeNB to the RN supporting RAN assisted WLAN interworking, the method further comprises: the DeNB carries the candidate WLAN list and the RAN auxiliary parameter list in the RN reconfiguration message and sends the RN;

3. The method of claim 1, wherein after the RN start-up procedure, the method further comprises:

4. The method of claim 1, wherein after the RN start-up procedure, the method further comprises:

5. The method of claim 1, wherein after the RN start-up procedure, the method further comprises:

6. The method of claim 5, wherein:

the RN determines a UE-specific RAN assistance parameter list based on RAN assistance parameter list decision information, the RAN assistance parameter list decision information including at least one of:

and (4) load measurement results of each WLAN in the coverage area of the RN.

7. The method of claim 6, wherein when the RAN assistance parameter list decision information includes load measurements of each WLAN in the coverage area of the RN, the RN further performs the following processing:

the RN establishes connection with the WLANs in the candidate WLAN list in sequence; wherein, if N1 WLANs are associated with the same WT, RN establishes Xw interface connection directly with the WT, but not with each WLAN hung down by the WT; if N2 WLANs are hung on the same SeGW, the RN directly establishes Xw interface connection with the security gateway SeGW, but does not directly establish connection with each WLAN hung under the SeGW; wherein, N1 and N2 are natural numbers;

8. The method according to any one of claims 1 to 7, wherein:

the newly added RN subframe configuration mode at least comprises a newly added RN subframe configuration mode;

9. The method according to any one of claims 1 to 7, wherein:

the candidate WLAN list is an ID list of WLAN Access Points (APs) in a range covered by a cell controlled by the RN;

10. A system for supporting RAN assisted WLAN interworking by a RN, the system comprising the following operations during RN start-up:

the RN takes the candidate WLAN list as a WLAN ID list in SIB17, takes the RAN auxiliary parameter list as a RAN auxiliary parameter list provided by the WLAN offload information IE in SIB17, and saves the candidate WLAN list and the RAN auxiliary parameter list.