24.3 Study on Improved network controlled mobility between lte and 3gpp2/mobile WiMax radio technologies uid_360016

Resources: R2

References

Document	Title/Contents
WID(s)
RP-070511	SID on Improved network controlled mobility between LTE and 3GPP2/mobile WiMAX radio technologies
Impacted Specifications
-	-
New Dedicated Specifications/Reports
TR 36.938	Improved Network Controlled Mobility between E-UTRAN and 3GPP2/Mobile WiMAX Radio Technologies

Supporting Individual Members: Motorola, Intel, Telecom Italia, Sprint, Samsung, NEC, Alcatel-Lucent, Vodafone, Nokia, Nokia Siemens Networks, Ericsson, Nortel, Qualcomm, KDDI, RIM

3GPP is going through Long Term Evolution and System Architecture Evolution implementation work and study items. Important LTE tasks include reduced latency, improved system capability, reduced cost per bit, higher user data rates. It is expected that IP based 3GPP services will be provided through various access technologies, including existing broadband radio access standards like IEEE 802.16e/ETSI BRAN, 3GPP2 including EVDO and 1xRTT.

This work:

• studies mobility between LTE and 3GPP2/mobile WiMAX systems in accordance with SA1 requirements;

• studies validity of existing 3GPP inter-RAT mobility mechanisms and their extendibility to non-3GPP RATs;

• identifies the versions of 3GPP2 and mobile WiMAX technologies (including technology variants) where mobility with LTE is needed;

• identifies frequency bands for which LTE and the studied non-3GPP systems should provide mobility support, including identification of duplex modes and channel bandwidths;

• characterizes impact on 3GPP UE supporting different solutions for handover between LTE and the studied non-3GPP technologies

• identifies requirements for availability of 3GPP2 and mobile WiMAX network configurations (including neighbour lists, raster index, cell identifiers) to 3GPP devices to enable mobility measurement of non-3GPP networks;

• identifies requirements for, and means of, reporting active mode measurements;

• identifies any additions to current mobility procedures.

TR 36.938 is a stage 2-level concept solution for each of the studied mobility scenarios which can be used as a basis for initiating Stage 3 work when moving to the implementation work item.

Even though a common solution is preferable, it is not required for the different mobility scenarios.

The solution developed for LTE – mobile WiMAX mobility should be reusable for UTRA – WiMAX mobility.

TR 36.938 Conclusions and Recommendations

Conclusions

Minimize impacts on legacy cdma2000 and reduce dependencies between E-UTRA and legacy cdma2000 systems. It was decided to:

• re-use cdma2000 interwork between HRPD and 1XRTT, e.g. supporting S101 interface similar to A21 to exchange messages between E-UTRAN and cdma2000;

• use RRC and S1AP tunnelling to transport cdma2000 messages over E-UTRAN;

• use RRC command to trigger UE to initiate handover preparation at target network via tunnelling;

• support network control of mobility;

• support single- and dual-radio UEs, including single-transmitter dual-receiver configuration.

The cdma2000 inter-working solution is based on multiple E-UTRA mechanisms, e.g. broadcast, measurement control, cell reselection and UE capability handling. Where these are not decided yet, the study proposes to keep alignment with the final E-UTRA decisions.

The eight work objectives and the General Requirement on E-UTRAN in TR 36.938 clause 5 are fulfilled for cdma2000 interworking with E-UTRA.

For mobility between E-UTRAN and WiMAX, studies were made on network architecture and interfaces, WiMAX system information in E-UTRAN, measurement control for RRC_IDLE and RRC_Connected UEs, cell reselection, and handover. Key solutions agreed and captured comprise:

• TWG release 1 and NWG release 1.0.0 as a target WiMAX release

• Architecture and interfaces with FAF, X200, S301, and X101

• Definition of WiMAX system information

• CINR and RSSI as WiMAX measurement quantities

• Threshold based on LTE_IDLE mode measurement control

• Network controlled measurement gap creation for LTE_ACTIVE UEs

• Use of periodic measurement reports and events-triggered measurement reports to report preamble index, measured result on preamble index and BS id

• Priority based cell reselection to WiMAX

• Handover procedure with pre-registration and handover preparation by UE tunnelling of corresponding WiMAX messages to the WiMAX while the UE is in E-UTRAN

Many solutions are derived from existing intra-3GPP inter-RAT mobility mechanisms and they will be aligned to the outcome of the intra-3GPP Stage 3 as much as possible. Transport mechanism and termination/origination points between E-UTRAN and WiMAX outside the scope of TSG RAN and for SA2's decision.

Progress was made meeting mobility requirements between E-UTRAN and mobile WiMAX radio technologies.

Recommendations

It is feasible (Stage 2 solution has been described) to support interworking between:

• cdma2000 and E-UTRAN

• WiMAX and E-UTRAN

Status Report in RP-070827