Collaborative MIMO Based on Multiple Base Station Coordination IEEE Presentation Submission Template (Rev. 9) Document Number: IEEE S802.16m-07/163, Coexistence of Collaborative MIMO with Single-Base-Station Based MIMO Date Submitted: Source: Yang SONG, Keying WU, Xiaolong ZHUVoice: * Venue: Call for Comments on SRD r m-07_002r3 Base Contribution: IEEE C802.16m-07/162, Collaborative MIMO based on multiple base station coordination Purpose: For m discussion and eventual adoption for standardization of the coexistence of SU-MIMO, MU-MIMO and Co-MIMO modes and their adaptive switching Notice: This document does not represent the agreed views of the IEEE 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 IEEEs name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEEs 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 Patent Policy: The contributor is familiar with the IEEE-SA Patent Policy and Procedures: and. Further information is located at and.

This contribution introduces the need for coexistence of the MIMO modes and their adaptive switching For m discussion and eventual adoption for standardization of the coexistence of single-user MIMO (SU-MIMO), multi-user MIMO (MU-MIMO) and collaborative MIMO (Co-MIMO) modes and their adaptive switching Purpose

Each MIMO mode (SU-MIMO, MU-MIMO, Co-MIMO) has its own preferred operating conditions and none can work optimally in universal environments. Different MIMO modes should be supported and selected (e.g. dynamically or semi-statically) according to a certain criteria in order to maximize the MIMO gain and meet the diversified system requirements. Motivation

Single-BS based MIMO –SU-MIMO Each user is served by only one BS with and it occupies the resource exclusively Preferred to single-user data rate increase and communication reliability enhancement –MU-MIMO several users are served by one common BS by sharing the same radio resource simultaneously. Favorable for heavily loaded systems where the maximization of overall system throughput is the primary concern Multi-BS based MIMO –Co-MIMO Each MS is jointly served by multiple BSs and at the same time each BS can serve several MSs simultaneously Efficient to improve the performance of cell-edge users by inter-cell interference (ICI) mitigation. Capable of throughput improvement Coexistence of MIMO Modes MIMO modes should coexist in a communication system, and be adaptively selected to cope with the diversified and complicated application scenarios.

By sharing the same time- frequency resource: –MS2 in the SU-MIMO mode. –MS1 in the Co-MIMO mode. –MS1 and MS3 in a mixed scenario of MU-MIMO and Co- MIMO. –BS1 manage to mitigate its interference to MS2. A scenario of Co-MIMO working with SU- MIMO and MU-MIMO

Channel quality indicator (CQI) per MS from neighboring BSs is a possible reference value for the adaptive switching. After MIMO mode scheduling, over the same radio resource –A BS may: Serve one MS with its all transmit antennas (SU-MIMO) Serve multiple MSs by SDMA (MU-MIMO or Co-MIMO) Serve one MS while mitigating interference to other MSs by interference nulling –For any MS, it may be: Served by one BS (SU-MIMO or MU-MIMO) Served by multiple BSs (Co-MIMO) Interference mitigated by one or more BSs Adaptive Switching among MIMO Modes