User Bitmap reconfiguration in Group resource allocation Document

User Bitmap reconfiguration in Group resource allocation Document Number: IEEE C 802. 16 m-09/1535 Date Submitted: 2009 -07 -06 Source: Jeongki Kim, Youngsoo Yuk, Kiseon Ryu, Ronny Yongho Kim E-mail: chegal@lge. com, sixs@lge. com, ksryu@lge. com, ronnykim@lge. com LG Electronics Re: Category: AWD comments / Area: Chapter 15. 2. 8 (Group Resource allocation) and Chapter 15. 3. 6 (DL-CTRL) “Comments on AWD 15. 2. 8 Group Resource Allocation and 15. 3. 6 DL-CTRL” Purpose: To be discussed and adopted in 802. 16 m AWD 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: <http: //standards. ieee. org/guides/bylaws/sect 6 -7. html#6> and <http: //standards. ieee. org/guides/opman/sect 6. html#6. 3>. Further information is located at <http: //standards. ieee. org/board/pat-material. html> and <http: //standards. ieee. org/board/pat >.

Introduction • In GRA A-MAP IE, User Bitmap is used to signal which users are scheduled in the frame – If a user is scheduled in the frame, the corresponding bit will be set to 1 • When an AMS is added to a group, the ABS allocates a User Bitmap index to the AMS • When an AMS is deleted from a group – Option 1: Variable user bitmap • If necessary, AMSs belonging to the group will shift their user bitmap indices – Option 2: Fixed user bitmap • AMSs belonging to the group don’t shift their user bitmap indices when there are deleted users in the group

Motivation • Option 1: Variable user bitmap – If an AMS losses the A-MAP IE, it results in ambiguity in index. Need a A-MAP error handling procedure • E. g. ) Need a Shared NAK channel or ACK channel – Implementation is complex • Option 2: Fixed user bitmap Option 1 – If there are many holes in User Bitmap due to deletion of users, it results in resource wastage • E. g. ) Worst case: User Bitmap size = 16, even though only two AMSs (AMS 1, AMS 16) belong to the group Option 2

User Bitmap reconfiguration • Use the semi-static User Bitmap – ABS reconfigures the User Bitmap when the User Bitmap needs to be reconfigured from large size to small size • E. g. ) User Bitmap size: 32 -> 16, 16 -> 8, 8 ->4 • This is an implementation issue – ABS includes the information related to user bitmap reconfiguration in GRA A-MAP IE • GRA A-MAP IE includes – Shifting indicator: Indicates whethere are User Bitmap indices which should be shifted at this frame and indicates that the size of User Bitmap is changed from large size to small size – User Bitmap size: Indicates the size of User Bitmap or the size of scheduled User Bitmap. • If Shifting indicator is set to 1, it indicates the size of User Bitmap. Otherwise, it indicates the size of scheduled User Bitmap • [0 b 00: 4, 0 b 01: 8, 0 b 10: 12, 0 b 11: 16] or [0 b 00: 8, 0 b 01: 16, 0 b 10: 24, 0 b 11: 32] – User Bitmap: Indicates the scheduled and unscheduled AMSs belonging to the Group • This is included in the GRA A-MAP IE only if Shifting indicator is set to 1

User Bitmap reconfiguration – Retransmission flag • Indicates whether the GRA A-MAP including User Bitmap is retransmitted – 0: The TX of GRA A-MAP including User Bitmap is the first transmission – 1: The GRA A-MAP including User Bitmap is retransmitted. That is, the User Bitmap has the size and structure of the previous User Bitmap • ABS will store the previous User Bitmap information until the AMSs which User Bitmap should be reconfigured receives the User Bitmap successfully – Re. Tx Bitmap • This field will be included only if retransmission flag is set to 1. Indicates which AMSs among AMSs which should shift their User bitmap indices in User Bitmap should shift their User bitmap indices at this frame. The size of Re. Tx Bitmap equals the number of AMSs which should shift their User Bitmap indices in User Bitmap. – Scheduled User Bitmap: Indicates the scheduled AMSs in a group • If shifting indicator is 0, the size of this Bitmap equals the User Bitmap size • If shifting indicator is 1, the size of this Bitmap equals the number of 1 s in User Bitmap. – Deletion indicator: Indicates whethere are one or more AMSs are deleted from the group – Deletion Bitmap: Indicates deleted AMSs at this frame. • If shifting indicator is 1 and retransmission flag is 0, Size equals number of 0’s in User Bitmap. [Otherwise, Size equals number of 0’s in scheduled user bitmap] or [Size equals number of 1’s in scheduled user bitmap]

Example (1/2) • When the User Bitmap size is reduced from 8 to 4.

Example (2/2) • AMS #5 did not receive the first GRA A-MAP IE including the User Bitmap

Proposed AWD text Change #1 • 15. 3. 6. 5. 2. 5 Group Resource Allocation A-MAP IE - Adopt the proposed text # 1 in CIEEE 802. 16 m-09_xxx or the latest revision of the contribution.