1. Mobility Management in 16m System Document Number: IEEE S802.16m-08/780r3 Date Submitted: 2008-07-14. Source: Yanling Lu, Luciano Sarperi, Mythri Hunukumbure, Rajni Agarwal, Kevin Power FujitsuE-mail:yanling.lu@uk.fujitsu.com Venue: IEEE 802.16m-08/024,” Call for Comments and Contributions on Project 802.16m System Description Document (SDD)”. Target topic: Mobility Management Base Contribution: IEEE C802.16m-08/780 Purpose: For discussion and approval by IEEE 802.16 Working Group Notice: This document does not represent the agreed views of the IEEE 802.16 Working Group or any of its subgroups. It represents only the views of the participants listed in the “Source(s)” field above. It is offered as a basis for discussion. It is not binding on the contributor(s), who reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE 802.16. Patent Policy: The contributor is familiar with the IEEE-SA Patent Policy and Procedures: and.http://standards.ieee.org/guides/bylaws/sect6-7.html#6http://standards.ieee.org/guides/opman/sect6.html#6.3 Further information is located at and.http://standards.ieee.org/board/pat/pat-material.htmlhttp://standards.ieee.org/board/pat

2. Mobility Management Requirements for 16m system Cell edge user performance enhancement Legacy support The maximum handover interruption time: 30 and 100 ms for inter- and intra- frequency handover of 16m MS between 16m BSs operating in the absence of legacy MSs under normal operating conditions.

3. Handover and Inter-cell Interference Mitigation Handover Area (B+C)Handover Area C Inter-cell Interference Mitigation

4. Handover and Inter-cell Interference Mitigation However, Inter-cell Interference Mitigation schemes have some disadvantages potentially: –Resource consuming –Side effects: impacting on other user’s signal quality Suggest new scheme: –IEEE C802.16m-08/449, targeting individual interfered cell edge userIEEE C802.16m-08/449 Trigger conditions: –Interference levels –Neighbor BS resources –Balance of system performance –..

5. Handover and Multi-cell MIMO Soft handover in 16m: –Avoid high drop-off rate during handover –MDHO Multi-cell MIMO : –Perform joint encoding in the DL and joint decoding in the UL –Better performance than with Macro-diversity –Potential baseline PHY technique for soft Handover

6. Handover with Legacy Support

7. 16m-starting handover –New message should be defined to inform the MS of the neighbor BS information. 16e-starting handover –Legacy message couldn’t contain enough information regarding the 16m neighbour BSs. –MS operation mode/serving zone is variable in the target BS with legacy support. –Handover procedure should address these problems.

8. Proposed Text 10.x Mobility management –Handover can be initiated by the MS or BS. The BS/network entity is responsible for determining the HO type, based on some criteria, such as loading balancing, admission control, security management and so on. –Inter cell interference mitigation should be utilized to enhance cell edge user’s performance, especially before the user potentially switches to the handover state. Multi-cell MIMO can be adopted as the physical baseline technique for soft handover. –Handover between legacy and new system shall be optimized to reduce latency. 16m MS operation mode should be notified as soon as possible. The handover network entry/scanning procedure should have the flexibility to address the change of MS operation mode.