E-MBS Zone Specific Pilot Patterns for MBSFN Document Number: IEEE C80216m-09/0929 Date Submitted: 2009-05-01 Source: Debdeep Chatterjee, Huaning Niu, Jong-kae (JK) Fwu, Hujun Yin Email: {debdeep.chatterjee@intel.com, huaning.niu@intel.com, jong-kae.fwu@intel.com, hujun.yin@intel.com} Intel Corporation Venue: IEEE Session #61, Cairo, Egypt. Re: Category: SDD CR / Area: Chapter 11.5.3.2 (E-MBS zone specific pilot patterns for MBSFN) “Comments on SDD section 11.5.3.2 E-MBS zone specific pilot patterns for MBSFN” Purpose: To discuss and adopt the proposed text in the revision of the 802.16m SDD. 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/sect6-7.html#6> and <http://standards.ieee.org/guides/opman/sect6.html#6.3>. Further information is located at <http://standards.ieee.org/board/pat/pat-material.html> and <http://standards.ieee.org/board/pat >.

Overview E-MBS content is to be transmitted in the SFN mode, with multiple BSs transmitting the same information for a particular MBS zone Delay spread is higher than typical unicast scenarios, and is dependent on the ISD and the MBSFN channel model Unicast pilot patterns are not sufficient Need new pilot pattern designs for E-MBS

Simulation Parameters OFDM parameters 10 MHz (1024 subcarriers) Number of OFDM symbols per subframe 6 Data burst size 4 PRUs distributed uniformly over 48 PRUs Permutation Tone based LDRU Number of total RU in one subframe 48 Number of Antennas 2 transmitter antennas, 2 receiver antennas [2Tx,2Rx] 1 transmitter antenna, 2 receiver antennas [1Tx,2Rx] Transmission mode Rate 1 transmission scheme: SFBC, SIMO Rate 2 transmission scheme: Spatial Multiplexing (SM) Channel coding LTE FEC with 8 Turbo decoding iterations Modulation/Coding QPSK ½, QPSK ¾, 16QAM ½, and 16QAM ¾ (for rate-1 transmission) 16QAM ½, and 16QAM ¾, 64QAM ½, and 64QAM ¾ (for rate-2 transmission) Channel model MBSFN channel models for 1.5km ISD and 5km ISD with MS speeds of 3kmph and 120kmph Channel estimation 2-D MMSE channel estimator with 3 PRU level CE Delay Spread perfectly known Actual PDP unknown, assumed to be flat at receiver MIMO detector LMMSE for SFBC and SM MRC for SIMO Scenarios Noise limited

Pilot Patterns Evaluated (1 of 3) = pilot tone (ant. 1); = pilot tone (ant. 2); = data tone

Pilot Patterns Evaluated (2 of 3) = pilot tone (ant. 1); = pilot tone (ant. 2); = data tone

Pilot Patterns Evaluated (3 of 3) = pilot tone (ant. 1); = pilot tone (ant. 2); = data tone

Power Delay Profile: MBSFN, 1.5km ISD

Throughput: 1.5km ISD, Speed=120kmph, 2x2SFBC INTC 5.5% pattern is the best choice, with very similar performances by MediaTek 5.56% and Samsung 5.56% patterns

Throughput: 1.5km ISD, Speed=120kmph, 1x2SIMO INTC 5.5% pattern is the best choice, with very similar performances by MediaTek 5.56% and Samsung 5.56% patterns

Throughput: 1.5km ISD, Speed=120kmph, SFBC & SIMO Comparison 1x2 SIMO is a better option as compared to 2x2 SFBC as a rate-1 scheme (Also check C.E. MSE on slide # 20)

Throughput: 1.5km ISD, Speed=120kmph, 2x2 SM INTC 5.5% pattern is the best choice, and slightly outperforms MediaTek 5.56% and Samsung 5.56% patterns ITRI 8.33% pattern slightly outperforms INTC 8.33%

5km ISD

Throughput: 5km ISD, Speed = 120kmph, 1x2 SIMO INTC 11.11% pattern appears to be the optimal choice INTC 8.33% pattern also provides a decent tradeoff, and outperforms LGE 7.41%, ITRI 8.33%, and Samsung A pattern (8.33%)

Summary 1x2 SIMO is a better option than 2x2 SFBC for rate-1 transmission Better overall channel estimation with less overhead Transmit diversity of SFBC not sufficient to overcome the increased overhead penalty We recommend two pilot patterns for different scenarios INTC 5.56% pattern for small cell sizes (e.g. 1.5km ISD) INTC 11.11% pattern for larger cell sizes (e.g. 5km ISD) The following patterns may also be considered (with loss of optimality) LGE 7.41% INTC 8.33% ITRI 8.33% INTC 11.11% may be more suitable for larger cell sizes, like 5km ISD, especially, if 2x2 SM is considered for these scenarios Samsung’s and MediaTek’s 5.56% pilot density patterns perform very close to the INTC 5.56% pattern, with the latter slightly outperforming the former two. More importantly, the 5.56% pilot density patterns fail to provide acceptable performance for the 5km ISD scenario

Proposed SDD Text Change: Replace the following text in red on page 81, line 17 of Section 11.5.3.2: “The definitions of the E-MBS zone specific pilots are FFS” with the following text in blue: “The E-MBS zone specific pilot patterns are specified within a PRU. Pattern 1, shown in Fig. xxx, is to be used for small cell sizes (e.g. 1.5km ISD), whereas Pattern 2, shown in Fig. yyy, is to be used for larger cell sizes (e.g. 5km ISD), with the subcarrier indices increasing from top to bottom, and OFDM symbol indices increasing from left to right.” Fig. xxx: E-MBS zone specific pilot Pattern 1 Fig. yyy: E-MBS zone specific pilot Pattern 2 = pilot tone (ant. 1); = pilot tone (ant. 2); = data tone

Appendix 3kmph Speed Throughput vs. SNR Results 1.5km ISD, 2x2 SFBC and 1x2 SIMO 1.5km ISD, 2x2 SM 5km ISD, 1x2 SIMO Channel Estimation MSE vs. SNR Results 1.5km ISD, 2x2 SFBC & SIMO

Throughput: 1.5km ISD, Speed = 3kmph, SFBC & SIMO

Throughput: 1.5km ISD, Speed = 3kmph, 2x2 SM

Throughput: 5km ISD, Speed = 3kmph, 1x2 SIMO

Channel Estimation MSE: 1 Channel Estimation MSE: 1.5km ISD, Speed=120kmph, SFBC & SIMO Comparison

Channel Estimation MSE: 1.5km ISD, Speed=120kmph, 2x2 SM

Channel Estimation MSE: 5km ISD, Speed=120kmph, 1x2 SIMO