1. Long CP frame structure design enabling time-multiplexed unicast and E-MBS Document Number: IEEE S80216m-08/1130r1 Date Submitted: 2008-09-15 Source: Dong Li, Hongwei Yang, Liyu Cai Voice:+86-21-58541240 Ext. 7796 Alcatel Shanghai Bell Co., Ltd E-mail:Hongwei.yang@alcatel-sbell.com.cnHongwei.yang@alcatel-sbell.com.cn Sophie Vrzic, Robert Novak, Mo-Han Fong, Dongsheng Yu, Jun Yuan, Hosein Nikopourdeilami Nortel Networks * http://standards.ieee.org/faqs/affiliationFAQ.html Venue: IEEE session #57, Kobe Base Contribution: IEEE C80216m-08/1130r2 Purpose: For discussion on the topic of SDD Cleanup-PHY. 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 S802.16m-08/1130r1

2. Introduction E-MBS is an important application scenario in 16m. Multi-cell SFN transmission of E-MBS may have to be relied on to provide sufficiently high SINR to achieve the E-MBS performance target specified in SRD The multi-cell SFN transmission will lead to large channel delay spread, which essentially requires a longer CP than 1/8 CP to avoid inter-symbol interference. A long CP subframe structure is provided, which enables efficient E-MBS SFN transmission on mixed carrier (TDM or hybrid TDM/FDM between unicast and E-MBS) or dedicated carrier.

3. Option 1: Unfixed SF duration with 1/4 CP ParametersValue Subcarrier spacing (KHz)10.9375 CP length (us) ， T CP 22.8571 Useful symbol time (us) ， T u 91.4286 Symbol time (us) ， T s = T CP +T u 114.2857 Num of OFDM symbols per frame43 Num of OFDM symbols per subframe5 or 6 Idle time (us)85.714 Problems with this option Unicast with normal CP cannot be time-multiplexed at the subframe level Legacy support (e.g., TDM at subframe level in DL/UL) may be disabled. The DL/UL cannot be exactly aligned with legacy network, which may result in some interference.

4. Option 2: Fixed SF duration with halved subcarrier spacing ParametersValue Subcarrier spacing (KHz)10.9375 CP length (us) ， T CP 22.8571 Useful symbol time (us) ， T u 91.4286 Symbol time (us) ， T s = T CP +T u 114.2857 Num of OFDM symbols per frame43 Num of OFDM symbols per subframe5 or 6 Idle time (us)85.714 Pros E-MBS SFN with longer CP can be time-multiplexed with unicast with 1/8 CP at the subframe level. Cons The halved subcarrier spacing will bring some performance degradation due to the increased sensitivity to frequency offset.

5. Option 3: Fixed subframe duration and subcarrier spacing (5.5 OFDM symbols/subframe) ParametersValue Subcarrier spacing (KHz)10.9375 CP length (us) ， T CP 18.9286 or 19.1071 Useful symbol time (us) ， T u 91.428 (45.714 for half symbol) Symbol time (us) ， T s = T CP +T u 110.54 or 110.36 (64.64 for half symbol) Num of OFDM symbols per frame40 full symbols and 8 half symbols Num of OFDM symbols per subframe5 full symbols and one half symbol Idle time (us)62.857 The potential problem is that the half OFDM symbol may bring some inconvenience in BB PHY processing

6. Option 4: Fixed subframe duration and subcarrier spacing (5 OFDM symbols/subframe) ParametersValue Subcarrier spacing (KHz)10.9375 CP length (us) ， T CP 31.964 Useful symbol time (us) ， T u 91.428 Symbol time (us) ， T s = T CP +T u 123.393 Num of OFDM symbols per subframe5 symbols Idle time at the end of subframe(us)0.179 SF duration = 0.617ms (i.e., equal to that of 1/8 CP SF) The long CP SF can be multiplexed with 1/8 CP SFs The long CP subframe can also be used to all the subframes.

7. Text Proposal Please refer to base contribution IEEE C80216m-08/1130r2.