July 2010
doc.: IEEE 802.11-10/0811r1
Pilot Sequence for VHT-DATA
Date: 2010-07-12
Authors:
Name
Affiliations Address
Phone
email
Allert van Zelst
Qualcomm
+31 346 259663
[email protected]
Richard van Nee
Qualcomm
+31 346 259650
[email protected]
Hemanth Sampath
Qualcomm
VK Jones
Qualcomm
Youhan Kim
Atheros
Vinko Erceg
Broadcom
Eldad Perahia
Intel
Raja Banerjea
Marvell
Youngsoo Kim
Samsung
Submission
Straatweg 66-S, 3621 BR
Breukelen, The Netherlands
Straatweg 66-S, 3621 BR
Breukelen, The Netherlands
5775 Morehouse Drive,
San Diego, CA, 92121, USA
3105 Kifer Road,
Santa Clara, CA, 95051,
USA
5480 Great America Pkwy
Santa Clara, CA 95054, USA
16340 W Bernardo Dr;
San Diego CA 92127, USA
2111 NE 25th Ave
Hillsboro, OR 97124, USA
5488 Marvell Lane
Santa Clara, CA 95054, USA
Mt. 14-1 Nongseo-Ri,
Giheung-Eup
Yongin-Si, Gyeonggi-Do,
Korea 449-712
Slide 1
[email protected]
m
[email protected]
+1-408-830-5835
[email protected]
[email protected]
[email protected]
[email protected]
+82-31-280-9614
[email protected]
om
Allert van Zelst, Qualcomm
July 2010
doc.: IEEE 802.11-10/0811r1
Abstract
A pilot sequence is proposed for VHT-DATA that can be
used in combination with the phase tracking during VHTLTF ([1]).
Submission
Slide 2
Allert van Zelst, Qualcomm
July 2010
doc.: IEEE 802.11-10/0811r1
Introduction
• As indicated in [1], single stream pilot tones during the
VHT-LTFs can be used to improve MIMO channel
estimation considerably, especially in case of phase
noise and/or residual carrier frequency offset on the
VHT-LTFs
• The pilot tones in VHT-LTF only provide a SIMO
channel estimate
• Since VHT-LTF pilots are single-stream, it makes sense
to also use a single stream pilot mapping for VHTDATA
Submission
Slide 3
Allert van Zelst, Qualcomm
July 2010
doc.: IEEE 802.11-10/0811r1
Pilot Sequence
•
•
For 20 and 40 MHz, the pilot sequence shall be the single spatial stream
pilot sequence of 11n copied to the NSTS streams before the per-stream
CSDs are applied.
For 80 MHz, the pilot sequence shall be the following sequence (which is
the 40 MHz pilot sequence for NSTS = 1 extended with a [1, 1] on the right,
resulting in the lowest PAPR on the pilot tones after applying [1 -1 -1 -1]
rotation on the 20 MHz subbands), copied to the NSTS streams before the
per-stream CSDs are applied:
0
1
2
3
4
5
6
7
1
1
1
-1
-1
1
1
1
20 MHz 1ss pilot sequence
40 MHz 1ss pilot sequence
Submission
Slide 4
Allert van Zelst, Qualcomm
July 2010
doc.: IEEE 802.11-10/0811r1
Application of Pilot Sequence in 20 MHz
• The pilot tone mapping in 20 MHz shall be:

Pn{21, 7,7, 21}  1,1nmod 4 , 1,1(n1) mod 4 , 1,1(n2) mod 4 , 1,1(n3) mod 4

• where 1,1m is given by the NSTS = 1 row of Table 20-18
of the 11n standard, and where n is the VHT-DATA
symbol index starting at 0.
• Including the pseudo random scrambling sequence, the
pilot value for the kth tone, with k = {-21, -7, 7, 21}, is
pn+zPnk, where z = 4 for VHT, and where pn is defined in
Section 17.3.5.9 of IEEE802.11.
Submission
Slide 5
Allert van Zelst, Qualcomm
July 2010
doc.: IEEE 802.11-10/0811r1
Application of Pilot Sequence in 40 MHz
• The pilot tone mapping in 40 MHz shall be:
Pn{53, 25, 11,11, 25,53}  {1,1nmod 6 , 1,1(n 1) mod 6 , 1,1(n  2) mod 6 , 1,1(n 3) mod 6 ,...
1,1(n  4) mod 6 , 1,1(n 5) mod 6 }
• where 1,1m is given by the NSTS = 1 row of Table 20-19 of the 11n
standard , and where n is the VHT-DATA symbol index starting at
0.
• Including the pseudo random scrambling sequence, the pilot value
for the kth tone, with k = {-53, -25, -11, 11, 25, 53}, is pn+zPnk, where
z = 4 for VHT, and where pn is defined in Section 17.3.5.9 of
IEEE802.11.
• This does not include the rotation per 20 MHz subband yet.
Submission
Slide 6
Allert van Zelst, Qualcomm
July 2010
doc.: IEEE 802.11-10/0811r1
Application of Pilot Sequence in 80 MHz
• The pilot tone mapping in 80 MHz shall be:
Pn{103, 75, 39, 11,11,39,75,103}  {n mod 8 , ( n 1) mod 8 , ( n  2) mod 8 , ( n 3) mod 8 ,...
( n  4) mod 8 , ( n5) mod 8 , ( n 6) mod 8 , ( n 7 ) mod 8 }
• where m is given in the table on slide 3, and where n is the VHTDATA symbol index starting at 0.
• Including the pseudo random scrambling sequence, the pilot value
for the kth tone, with k = {-103, -75, -39, -11, 11, 39, 75, 103}, is
pn+zPnk, where z = 4 for VHT, and where pn is defined in Section
17.3.5.9 of IEEE802.11.
• This does not include the rotation per 20 MHz subband yet.
Submission
Slide 7
Allert van Zelst, Qualcomm
July 2010
doc.: IEEE 802.11-10/0811r1
Application of Pilot Sequence in 160 MHz
• For 160 MHz transmissions, the pilot mapping shall be
the replication of the 80 MHz pilot mapping (as given
on slide 7) in the two 80 MHz subbands for 160 MHz
VHT-DATA symbols.
Submission
Slide 8
Allert van Zelst, Qualcomm
July 2010
doc.: IEEE 802.11-10/0811r1
Straw Poll
• Do you support adding the following paragraph in the
specification framework document, 11-09/0992?
– Pilot Subcarriers
• [Copy the text of slides 4 – 8]
Submission
Slide 9
Allert van Zelst, Qualcomm
July 2010
doc.: IEEE 802.11-10/0811r1
References
[1]
Submission
Kai Shi et al, “Phase Tracking During VHT-LTF”,
IEEE 802.11-10/0771r0, July 2010
Slide 10
Allert van Zelst, Qualcomm