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Comparison of DL Pilot Patterns

IEEE 802.16 Presentation Submission Template (Rev. 9) Document Number:

IEEE C802.16m-08/798r1Date Submitted:

2008-07-07Source:

Jinsoo Choi, HanGyu Cho, Bin-chul Ihm, Wookbong LeeE-mail:{emptylie, hgcho, bcihm, wbong}@lge.comLG Electronics, Inc.

Venue:TGm call for comments on IEEE 802.16m-08/024. Specific topic : “DL Pilot scheme”

Base Contribution:N/A

Purpose: To be discussed and adopted by TGm

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.

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<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 >.

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Simulation Assumption◙ LLS Simulation defined by “C802.16m-08/518” Appendix A.

◙ Common pilot –MMSE channel estimation using pilots over multiple PRUs (frequency domain), Dedicated pilot - MMSE channel estimation per RU

◙ Normalized throughput for noise limited simulation

◙ 2Tx SM/SFBC, 4Tx SM/SFBC, 4Tx pre-coding rank1(fixed codebook)

◙ Pilot boosting (2Tx SM/SFBC: 3dB, 4Tx SM/SFBC : 6dB, 4Tx pre-coding rank1 : non boosting)

◙ MCS: QPSK ½, 16QAM ½, 64QAM ½

◙ Distributed subchannelization defined by “C80216m-08_517r1” for common pilot and localized subchannelization for dedicated pilot

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Common pilot patterns for 2Tx◙ Referred by “C802.16mDL_PHY-08/009r5”

<Intel> <Samsung> <Motorola> <LGE><MediaTek>

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Performance comparison for 2Tx common pilot patterns

◙ LGE, Intel, Samsung almost show best performance.

◙ Motorola shows good performance in some SNR regions.

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Common pilot patterns for 4Tx◙ Referred by “C802.16mDL_PHY-08/009r5”

<Intel> <Samsung> <Motorola> <LGE><MediaTek>

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Performance comparison for 4Tx common pilot patterns

◙ LGE shows almost best performance.

◙ Motorola shows good performance in some SNR regions.

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Dedicated pilot patterns for 4Tx◙ Referred by “C802.16mDL_PHY-08/009r5”

<Intel> <Samsung> <Motorola> <LGE><MediaTek>

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Performance comparison for 4Tx dedicated pilot patterns

◙ LGE, Motorola, MediaTek show best performance until 16dB region.

◙ Samsung and Intel show best performance over 16dB region.

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Conclusion◙ In 2Tx configuration with common pilot

With equal pilot density, each pattern has similar performance. 11.11% pilot density seems to be proper pilot overhead. LGE, Intel, Samsung have almost best performance.

◙ In 4Tx configuration with common pilot The pilot pattern of LGE shows almost best performance.

◙ In 4Tx configuration with dedicated pilot LGE, Motorola, MediaTek have best performance until middle SNR r

ange. Samsung and Intel show best performance in high SNR range.

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Proposed Text for SDD (1)Insert the following into SDD Section 11.5.3 in IEEE 802.16m-08/003r3

11.5.3 Pilot Structure11.5.3.1 Common pilot structure

<Figure x_1: 2 transmit pilot pattern>

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Proposed Text for SDD (2)

11.5.3 Pilot Structure11.5.3.2 Dedicated pilot structure

<Figure x_3: 2 transmit pilot pattern>

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Appendix – Separated results for each MCS

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2Tx common pilot patterns

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2Tx common pilot patterns

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4Tx common pilot patterns

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4Tx common pilot patterns

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4Tx dedicated pilot patterns