Mar 2020 doc IEEE 802 11 200456 r

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Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Tx EVM Requirement for

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Tx EVM Requirement for 4 k QAM Date: 03/12/2020 Authors: Name Phone Email Yaron Yoffe Yaron. [email protected] com Shlomi Vituri Shlomi. [email protected] com Qinghua Li Qinghua. [email protected] com Feng Jiang Xiaogang Chen Affiliation Address Intel Assaf Gurevitz Uri Perlmutter Gadi Shor Laurent Cariou Submission Slide 1 Y. Yoffe, et. al, Intel

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Problem Statement • 4

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Problem Statement • 4 k QAM boosts the peak data rate but requires high EVMs • However, there is a tradeoff between EVM and transmission power • In this contribution, we show the EVM requirements for 4 k QAM Submission Y. Yoffe, et. al, Intel

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Common Usage Scenario •

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Common Usage Scenario • 80 MHz channel, fading Channel D • 4 x 2 SU MIMO with 4 Tx antennas, 2 Rx antennas, 2 streams • Beamforming applied Bea mfo AP rmin g STA Submission Y. Yoffe, et. al, Intel

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Tx EVM • It

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Tx EVM • It includes channel estimation errors and is 3 d. B worse than the actual distortion at the transmitter • It is modeled as AWGN, which is the worst case • EVM due to phase noise can be mostly cancelled by pilot tracking MCS Parameters • Highest MCS with 4 k QAM and LDPC 5/6 • 4 k bytes per packet, 20 packets per PPDU Submission Y. Yoffe, et. al, Intel

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 With ideal channel estimation

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 With ideal channel estimation Curve spacing gets smaller and smaller Submission Y. Yoffe, et. al, Intel

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 With LTF based channel

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 With LTF based channel estimation Curve spacing gets smaller and smaller Submission Y. Yoffe, et. al, Intel

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Degradation vs. EVM •

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Degradation vs. EVM • Degradation is with respect to no EVM case • It gets harder and harder to reduce the degradation as the EVM approaches zero. Namely, each d. B of EVM drop produces less and less degradation drop e. g. 0. 1 -0. 2 d. B per EVM d. B drop. Tx EVM (d. Bc) -36 -37 -38 -39 Degradation with ideal Degradation with channel (d. B) estimated channel (d. B) 1. 1 0. 9 0. 7 0. 5 1. 1 0. 8 0. 6 0. 5 -38 EVM is a good choice balancing Tx power and distortion Submission Y. Yoffe, et. al, Intel

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Phase noise effect with

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Phase noise effect with ideal channel estimation • Phase noise power is calculated from 10 k – 200 MHz and normalized with respect to the total power of the other distortions Low frequency phase noises are cancelled by removing the common phase rotation Submission Y. Yoffe, et. al, Intel

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Conclusion • -38 d.

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Conclusion • -38 d. B Tx EVM is a reasonable choice • Degradation is small i. e. about 0. 6 d. B from the ideal • Further EVM reduction may require additional Tx power reduction that shortens the 4 k QAM usable range Submission Y. Yoffe, et. al, Intel

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Straw Poll • Do

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Straw Poll • Do you support -38 d. B as the Tx EVM requirement for 11 be 4 k QAM? • Y: Submission N: A: Y. Yoffe, et. al, Intel

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Backup Submission Y. Yoffe,

Mar 2020 doc. : IEEE 802. 11 -20/0456 r 0 Backup Submission Y. Yoffe, et. al, Intel