Base Frame Structure for IEEE m IEEE Presentation Submission Template (Rev. 9) Document Number: IEEE S802.16m-08/081 Date Submitted: xx Source: Jerry Chow, Sean Cai, Qu Hongyun, Fang HuiyingVoice:[Telephone Number (optional)] ZTE Juejin Liu, Sean McBeath, Jianmin Lu, Lian Yang, Mingyang Sun {juejunliu, smcbeath, Huawei Technologies Dong Xiaolu, Du CATR Xiao Shanpeng, Liao China Mobile Suo Datang Mobile Su Xin, Zhong Tsinghua University * Venue: IEEE m-07/047 – Call for Contributions on Project m System Description Document (SDD) – Frame Structure Base Contribution: IEEE m-08/081 Purpose: Adopt proposed text in base contribution into Project m SDD under the topic of Frame Structure 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 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 Patent Policy: The contributor is familiar with the IEEE-SA Patent Policy and Procedures: and. Further information is located at and.

2 IEEE S802.16m-08/ m Frame Structure: Framework Overview

3 IEEE S802.16m-08/081 Design Approach for 16m Frame Structure Define flexible framework –16m required to satisfy many diverse requirements, such as wide range of mobile speeds and wide range of coverage ranges –To facilitate appropriate tradeoffs, avoid tightly coupling aspects that should be controlled independently (e.g. frequency of frame sync vs. frequency of DL/UL switching) Mitigate impact of legacy support on 16m operation –Maintain as much independence as possible between 16m and legacy operation Common framework for TDD, FDD, H-FDD, and multi- carrier Minimize control overhead while retaining sufficient flexibility

4 IEEE S802.16m-08/081 General 16m Frame Structure

5 IEEE S802.16m-08/081 Main Elements of 16m Frame Structure Frame –Outer structure with synchronization signal(s) to allow MS to acquire alignment with frame structure Frame Partition –Allows shorter timeframe than a frame for which decisions on allocations to MSs and radio resource configurations apply Subframe –A continuous duration within frame partition with transmissions in a common direction (downlink or uplink) Subframe Partition –A continuous duration within subframe possessing particular PHY properties

6 IEEE S802.16m-08/081 Main Elements of 16m Frame Structure (Cont’d) Unit Subframe –Smallest time unit structure within frame (above OFDM symbol) –Is comprised of one or more OFDM symbols and possibly time gaps (idle times) –Has particular PHY structure and resource organization –Contains indivdiually addressable radio resource units

7 IEEE S802.16m-08/081 Unit Subframe

8 IEEE S802.16m-08/081 Legacy Support via TDM in TDD Mode

9 IEEE S802.16m-08/081 Key Aspects of Legacy 16e Support Within 16m frame structure, reserve NULL sub-frame partitions for legacy 16e use 16m has separate frame boundary from legacy 16e –16m frame has new Preamble distinct from the existing Preamble for legacy 16e – allows independent operation for Legacy 16e MSs and new 16m MSs Fixed relative offset between start of 16m frame and start(s) of legacy 16e frames that reside within the time window of the 16m frame –Set 16m frame duration to be an integer multiple of the imbedded legacy 16e frame(s)

10 IEEE S802.16m-08/081 Key Aspects of Legacy 16e Support (Cont’d) Allow 16m subframe partition(s) of possibly opposite direction in between legacy 16e allocations within the legacy 16e DL or UL subframe – mitigate delay impact on 16m operation Can dynamically switch between 16m and legacy 16e use on 16m subframe-partition basis as long as directions (DL, UL) are same –e.g. subframe partitions designated for DL in 16m can be used for 16e DL within the 16e DL subframe time

11 IEEE S802.16m-08/081 FDD/Multi-carrier Via Simple Extension

12 IEEE S802.16m-08/081 Key 16m Frame Structure Attributes Common frame structure elements and control as used for 16m TDD frame Define FDD case as a subset case of general operation with multiple-carrier BS –Should be same configuration and control mechanisms –Main characteristic of FDD sub-case is that main carrier is configured to have only DL sub-frames and an auxiliary carrier is configured to have UL sub-frames only H-FDD supported in framework via appropriate offset of corresponding frame partitions between DL and UL carriers

13 IEEE S802.16m-08/ m Frame Structure: Considerations on Preamble

14 IEEE S802.16m-08/081 Preamble – Option 1 The 16m frame preamble in the Frame Sync and Control signal is located at the start of the 16m frame.

15 IEEE S802.16m-08/081 Preamble – option 2 The frame preamble consists of three OFDM symbols, which are located at the end of a DL subframe, which precedes an UL subframe. The cyclic prefix length of the P-SCH and S-SCH is fixed.

16 IEEE S802.16m-08/081 Preamble – option2 (cont.) Superframe Preamble –2 OFDM Symbols (P-SCH and S-SCH) with a fixed cyclic prefix length P-SCH –Located in the center of the traffic bandwidth –Occupies 5 MHz bandwidth (around the center frequency when bandwidth is above 5MHz ) S-SCH –Sector Identity Broadcast Channel (BCH) contains the following information: –CP length for the traffic symbols –The size of the multicast control segment –Antenna configuration –Other content for further study

17 IEEE S802.16m-08/ m Frame Structure: Example Configuration and Details on Resource Control within Unit Subframe

18 IEEE S802.16m-08/081 Example Configuration of m Frame

19 IEEE S802.16m-08/081 Unit Subframe Resource Addressing via Channel Tree To reduce control channel overhead, a channel tree is defined for 16m. –A unique channel tree is defined within each unit subframe (or within subframe partition TBD) A channel tree is defined by its base-nodes. –Tradeoff between resource granularity and control channel overhead must be considered. –One base node: 14 subcarriers (data + traffic) × 6 OFDM symbols 10 MHz = 60 base nodes 5 MHz = 30 base nodes Other resource assignment method is under consideration

20 IEEE S802.16m-08/081 Unit Subframe Resource Addressing (Opt. 1) Option 1: Organized as Nodes in Annular Channel Tree 32 Base Node Example Base nodes on outside of circle Parent nodes on inside of circle

21 IEEE S802.16m-08/081 Unit Subframe Resource Addressing (Opt. 2) Option 2: Organized as Hybrid Between Binary Channel Tree and Bitmap Example 1: Parent Node 6 + bitmap ‘1000’ = base node 27 Example 2: Parent Node 4 + bitmap ‘1110’ = base nodes 19, 20, 21 Example 3: Parent Node 0 + bitmap ‘1100’ = channel tree nodes 3, 4 This delineation is a system parameter, thereby making the assignment overhead flexible.

22 IEEE S802.16m-08/081 Unit Subframe Control Channels The control channel is composed of two pieces: multicast and unicast –The multicast control segment contains the following information, which is jointly encoded: Indication of the division of the frequency domain into multiple subzones Subcarrier permutation Other content for further study –Multiple unicast control segments are defined, where each segment contains one assignment The unicast assignments are located at the beginning of each subzone –The assigned time-frequency resource is not restricted to the corresponding subzone

23 IEEE S802.16m-08/081 Unit Subframe Control Channels (Cont’d)