CTPClassification=CTP_PUBLIC:VisualMarkings=
doc.: IEE
IEEE P802.11
Wireless LANs
Clause 20 SC MCS Extension
Date: 2015-10-08
Author(s):
Name
Assaf Kasher
Alecsander Eitan
Payam Torab
Brad Lynch
Christopher
Hansen
Dmitry
Cherniavsky
HanGyu Cho
Affiliation
Intel
Corporation
Qualcomm Inc.
Broadcom Ltd.
Peraso
Address
Matam Industrial Park,
Haifa, Israel, 31015
Phone
email
+97248651547
[email protected]
[email protected]
[email protected]
[email protected]
Peraso
[email protected]
Sibeam
[email protected]
om
LGE
[email protected]
Abstract
This document provides the details of the changes needed for adding 7 more rates: one QPSK, two 16QAM and 4 64-QAM, to the SC PHY subclause. All references are to TGmc D5.0
Submission
page 1
CTPClassification=CTP_PUBLIC:VisualMarkings=
doc.: IEEE 802
Discussion (1):
In 11ad PHY (clause 20 in TGmc Draft 5.0) there is incompatibility between the OFDM mode
and the mandatory SC mode. When a packet is sent in OFDM mode, SC only receiver cannot
determine its length because it is coded inside an OFDM header. We therefore think that OFDM
should not be implemented. To achieve the high rates allowed by the OFDM mode, we propose
to add new MCSs to the SC mode. This is done in a way that is fully compatible with devices
complying with the 11ad standard.
Editor: replace the penultimate row of table 20-17 (SC header fields) with the following two
lines:
Extended SC MCS
1
44
Corresponds to the TXVECTOR parameter
Indication
EXTENDED_SC_MCS.
Set to 0 to indicate regular interpretation of
the MCS field.
Set to 1 to indicate that MCS 7-9 represent
64-QAM Modulations rather than QPSK
Modulation with the same code rate, MCS 10
represents 16-QAM modulation with code
rate 7/8, MCS12 represents 64-QAM
Modulations with code rate of 7/8, MCS5
represents 16-QAM Modulations with code
rate of 13/16, and MCS6 represents QPSK
modulation with code rate of 7/8 rather than
code rate of 1/2.
Reserved
3
45
set to 0, ignored by receiver
Editor: add the following text to the description of the length field in table 20-17 (SC header
fields):
If Extended SC MCS Indication field is 1, the length of the PSDU is computed according to
Table 20-NEW. The number of data octets in the PSDU shall not exceed 262143.
Table 20-NEW—Length value in SC header for Extended MCSs
Extended MCS
12.1
12.3, 12.4, 12.5
9.1,12.2, 12.6
Length
𝑑𝑎𝑡𝑎 𝑜𝑐𝑡𝑒𝑡𝑠 𝑖𝑛 𝑡ℎ𝑒 𝑃𝑆𝐷𝑈
⌈
⌉
4
𝑑𝑎𝑡𝑎 𝑜𝑐𝑡𝑒𝑡𝑠 𝑖𝑛 𝑡ℎ𝑒 𝑃𝑆𝐷𝑈
⌈
⌉
3
𝑑𝑎𝑡𝑎 𝑜𝑐𝑡𝑒𝑡𝑠 𝑖𝑛 𝑡ℎ𝑒 𝑃𝑆𝐷𝑈 × 4
⌈
⌉
7
value in MCS field
5
7,8,9
6, 10, 12
Editor: add the following line after line 10 of table 20-18 (Modulation and coding scheme for
SC):
9.1
π/2-QPSK
2
1
7/8
2695
Editor: add the following lines (at the end) to table 20-18 (Modulation and coding scheme for
SC):
Submission
page 2
CTPClassification=CTP_PUBLIC:VisualMarkings=
12.1
12.2
12.3
12.4
12.5
12.6
π/2-16QAM
π/2-16QAM
π/2-64QAM
π/2-64QAM
π/2-64QAM
π/2-64QAM
4
4
6
6
6
6
1
1
1
1
1
1
doc.: IEE
13/16
7/8
5/8
3/4
13/16
7/8
5005
5390
5775
6930
7507.5
8085
Editor: add the following subclause after subclause 20.6.3.2.4.4:
20.6.3.2.4.5 π/2-64QAM Modulation
In the π/2-64QAM modulation, the input bit stream is grouped in sets of 6 bits and mapped
according to the following equation:
𝑠̃𝑘
1
=
((8𝑐6𝑘 − 4) − (2𝑐6𝑘 − 1)(4𝑐6𝑘+1 − 2) + (2𝑐6𝑘 − 1)(2𝑐6𝑘+1 − 1)(2𝑐6𝑘+2 − 1))
√42
𝑗
+
((8𝑐6𝑘+3 − 4) − (2𝑐6𝑘+3 − 1)(4𝑐6𝑘+4 − 2) + (2𝑐6𝑘+3 − 1)(2𝑐6𝑘+4 − 1)(2𝑐6𝑘+5 − 1))
√42
where k is the output symbol index, k=0,1, …. Each output symbol is then rotated according to
the following equation 𝑠𝑘 = 𝑠̃𝑘 ∙ 𝑒
64QAM constellation bit encoding.
𝑗𝜋𝑘
2
. The constellation bit encoding is depicted in Figure 1c6kc6k+1c6k+2c6k+3c6k+4c6k+5
Q
000 100
001 100
011 100
010 100
7
110 100
111 100
101 100
100 100
000 101
001 101
011 101
010 101
5
110 101
111 101
101 101
100 101
000 111
001 111
011 111
010 111
3
110 111
111 111
101 111
100 111
000 110
001 110
011 110
010 110
1
110 110
111 110
101 110
100 110
-7
-5
-3
-1
1
3
5
7
000 010
001 010
011 010
010 010
-1
110 010
111 010
101 010
100 010
000 011
001 011
011 011
010 011
-3
110 011
111 011
101 011
100 011
000 001
001 001
011 001
010 001
-5
110 001
111 001
101 001
100 001
000 000
001 000
011 000
010 000
-7
110 000
111 000
101 000
100 000
I
Figure 1-64QAM constellation bit encoding
Editor: Add the following lines to table 20-20 (Values of NCBPB)
Submission
page 3
CTPClassification=CTP_PUBLIC:VisualMarkings=
π/2-64QAM
doc.: IEEE 802
2688
Editor: Add the following line after the 6th line of table 20-21 (EVM requirements of DMG SC mode)
9.1
7/8
-16
π/2-QPSK
Editor: Add the following lines to table 20-21 (EVM requirements of DMG SC mode)
12.1
13/16
-22
π/2-16QAM
12.2
7/8
-23
π/2-16QAM
12.3
5/8
-26
π/2-64QAM
12.4
3/4
-27
π/2-64QAM
12.5
13/16
-29
π/2-64QAM
12.6
7/8
-31
π/2-64QAM
Editor: Add the following line to table 20-3 (Receiver sensitivity) after the line of MCS Index
9:
-57
9.1
Editor: Add the following lines to table 20-3 (Receiver sensitivity) after the line of MCS Index
12:
-51
12.1
-50
12.2
-48
12.3
-46
12.4
-44
12.5
-42
12.6
Editor: add the following line to table 20-1 after the MCS line:
EXTENDED_SC_MCS Enumerated Type:
- NON_EXTENDED_MCS: indicates regular
interpretation of the MCS field
- EXTENDED_MCS: indicates that MCS 7-9
represent 64-QAM Modulations rather than QPSK
Modulation with the same code rate, MCS 10
represents 16-QAM with code rate 7/8, MCS12
represents 64-QAM Modulations with code rate of
7/8, MCS5 represents 16-QAM Modulations with
code rate of 13/16, and MCS6 represents QPSK
modulation with code rate of 7/8 rather than code
rate of 1/2.
This parameter is reserved for all other MCSs.
Y
Y
Editor: add at the end of section 20.6.3.1.1 General the following lines:
When the EXTENDED_SC_MCS field in the TXVECTOR (see table 20-1) is set to EXTENDED_MCS,
the rules for setting the bits X1–X7 of the initial scrambler state are as follows
Submission
page 4
CTPClassification=CTP_PUBLIC:VisualMarkings=
-
-
-
doc.: IEE
For MCS 12.1, bits (X6, X7) are set according to:
𝑑𝑎𝑡𝑎 𝑜𝑐𝑡𝑒𝑡𝑠 𝑖𝑛 𝑡ℎ𝑒 𝑃𝑆𝐷𝑈
⌈
⌉ ∗ 4 − 𝑑𝑎𝑡𝑎 𝑜𝑐𝑡𝑒𝑡𝑠 𝑖𝑛 𝑡ℎ𝑒 𝑃𝑆𝐷𝑈
4
Bits (X1-X5) are set according to the transmitter implementation.
For MCS 12.3, 12.4, 12.5 , bits (X6, X7) are set according to:
𝑑𝑎𝑡𝑎 𝑜𝑐𝑡𝑒𝑡𝑠 𝑖𝑛 𝑡ℎ𝑒 𝑃𝑆𝐷𝑈
⌈
⌉ ∗ 3 − 𝑑𝑎𝑡𝑎 𝑜𝑐𝑡𝑒𝑡𝑠 𝑖𝑛 𝑡ℎ𝑒 𝑃𝑆𝐷𝑈
3
Bits (X1-X5) are set according to the transmitter implementation.
For MCS 9.1, 12.2 and MCS 12.6, bit X7 is set according to:
𝑑𝑎𝑡𝑎 𝑜𝑐𝑡𝑒𝑡𝑠 𝑖𝑛 𝑡ℎ𝑒 𝑃𝑆𝐷𝑈 ∗ 4 7
⌊⌈
⌉ ∗ ⌋ − 𝑑𝑎𝑡𝑎 𝑜𝑐𝑡𝑒𝑡𝑠 𝑖𝑛 𝑡ℎ𝑒 𝑃𝑆𝐷𝑈
7
4
Bits (X1-X6) are set according to the transmitter implementation.
X1-X7 are sent in the Scramber Initialization field, as defined in 20.6.3.1.4, and 20.6.3.2.2..
Editor: Add the following text after P2465L29:
𝐿
When the code rate 𝑅 is 7/8, 𝐿𝐶𝑊 = 624 and for the purpose of 𝑁𝐶𝑊 computation 𝐶𝑊
𝑅 = 546.
𝜌
Editor: modify the text in P2465L36-44 as follows:
a. If  = 1, and the code rate is not 7/8
i. The output stream of the scrambler is broken into blocks of LCWD = LCW ×R bits


m)
such that the mth data word is b1( m ) , b2( m) ,...bL(CWD
, m NCW . .
ii. To each data word, n-k=LCW-R×LCW parity bits
to create the code word

 p  , p  ,
m
1
m
2

, pn mk are added
m)
c ( m)  b1( m) , b2( m) ,..., bL(CWD
, p1( m) ,... pn( mk)

such that
Hc m   0
T
If ρ = 1 and the code rate is 7/8, 48 bits are punctured from the parity bits of the rate
13/16 parity bits:
i.
The output stream of the scrambler is broken into blocks of 546 bits such that
(𝑚) (𝑚)
(𝑚)
the mth data word is (𝑏1 , 𝑏2 , … , 𝑏546 ) , 𝑚 ≤ 𝑁𝐶𝑊 .
ii.
(𝑚)
To each data word, 126 parity bits (𝑝1
(𝑚)
the code word 𝒄̃(𝑚) =(𝑏1
(𝑚)
(𝑚)
(𝑚)
, 𝑝2 , … , 𝑝126 ) are added to create
(𝑚)
(𝑚)
, 𝑏2 , … , 𝑏546 , 𝑝1
(𝑚)
(𝑚)
, 𝑝2 , … , 𝑝126 ) such that
𝑇
𝑯𝒄̃(𝑚) = 𝟎. The code word 𝒄(𝑚) is generated from 𝒄̃(𝑚) by removing the
(𝑚) (𝑚)
(𝑚) (𝑚) (𝑚)
(𝑚)
first 48 parity bits so that 𝒄(𝑚) = (𝑏1 , 𝑏2 , … , 𝑏546 , 𝑝49 , 𝑝50 , … , 𝑝126 )
Editor Add the following line after the line of MCS 9 in Table 20-23—Zero filling for SC BRP
packets:
9.1
π/2-QPSK 2
1
7/8
2695
25
Editor Add the following lines after the last line of Table 20-23—Zero filling for SC BRP
packets:
12.1
1
13/16
π/2-16QAM 4
5005
46
12.2
1
7/8
π/2-16QAM 4
5390
49
Submission
page 5
CTPClassification=CTP_PUBLIC:VisualMarkings=
π/2-64QAM
π/2-64QAM
π/2-64QAM
π/2-64QAM
12.3
12.4
12.5
12.6
6
6
6
6
1
1
1
1
doc.: IEEE 802
5/8
3/4
13/16
7/8
5775
6930
7507.5
8085
69
69
69
74
Editor: Add a 1 octet field to figure 9-502 (DMG Capabilities element format) in page 1010: Extended
SC MCS capabilities
Element
Element ID
ID
Length
Length
STA
STA Address
Address
AID
AID
DMG
DMG STA
STA Capability
Capability
Information
Information
DMG
DMG AP
AP or
or PCP
PCP
Capability
Capability
Information
Information
DMG
DMG STA
STA Beam
Beam
Tracking
Tracking Time
Time
Limit
Limit
Extended
Extended SC
SC
MCS
MCS
Capabilities
Capabilities
1
1
6
1
8
2
2
1
Editor: Add the following subclause at P1016L21 (before 9.4.2.129)
9.4.2.128.5 Extended SC MCS Capabilities field
The Extended SC MCS Capabilities field (see figure 9-50X) advertises the support of the STA to
extended SC MCSs.
B0
B2
Maximum Extended SC
Tx MCS
Bits:
3
B3
B4
B6
B7
Code
Rate
7/8 Tx
Maximum Extended SC
Rx MCS
Code
Rate
7/8 Rx
1
3
1
Figure 9-50X Extended SC MCS capabilities field
The Maximum Extended SC Tx MCS subfield indicates the maximum transmit extended SC MCS
supported by the STA. The values in the subfield are ordered as shown in table 9-22X:
Table 9-22X – Mapping of Extended SC MCS to Maximum Supported Rx/Tx MCS subfields values
Extended MCS name
Value in Maximum
Extended SC Rx/Tx
MCS field
None
0
MCS 9.1
1
MCS 12.1
2
MCS 12.2
3
MCS 12.3
4
MCS 12.4
5
MCS 12.5
6
MCS 12.6
7
A STA that indicates support for transmission of an Extended SC MCS by setting the value in the
Maximum Extended SC Tx MCS subfield to k, supports all Extended SC MCSs with values lower than or
equal to k.
A STA indicates support for transmission of code rate 7/8 by setting the value in this subfield to 1. If
STA indicates that it does not support code rate 7/8, then the STA does not support MCS 9.1 or 12.2 even
if the value in the Maximum Extended SC Tx MCS subfield is greater than 1 or 3 respectively.
A STA that indicates support for reception of an an Extended SC MCS by setting the value in the
Maximum Extended SC Rx MCS subfield to k, supports all Extended SC MCSs with values lower than or
equal to k.
A STA indicates support for reception of code rate 7/8 by setting the value in this subfield to 1. If STA
indicates that it does not support code rate 7/8, the the STA does not support MCS 9.1 or 12.2 even if the
value in the Maximum Extended SC Rx MCS field is greater than 1 or 3 respectively.
Submission
page 6
CTPClassification=CTP_PUBLIC:VisualMarkings=
Editor: modify the text in P1013L16-18 as follows:
The Maximum SC Rx MCS subfield contains the value of the maximum MCS index the STA
supports for reception of single-carrier frames. Values 0-3 of this (#3097) subfield are reserved.
Possible values for this subfield are shown in Table 20-18 (Modulation and coding scheme for
SC) (values for Extended SC MCSs are not valid for this field).
Editor: modify the text in P1013L27-29 as follows:
The Maximum SC Tx MCS subfield contains the value of the maximum MCS index the STA
supports for transmission of single-carrierframes. Values 0-3 of this (#3097) subfield are
reserved. Possible values for this subfield are shown in Table 20-18 (Modulation and coding
scheme for SC) (values for Extended SC MCSs are not valid for this field).
Editor: Modify the text in P1033L31-35 (in subclause 9.4.2.141.1)
The MCS field is set to an MCS value that the STA sending this element recommends that the
peer STA indicated in the RA field of the Link Measurement Report frame use to transmit
frames to this STA. The reference PER for selection of the MCS is 10-2 for an MPDU length of
4096 octets. The method by which the sending STA determines a suitable MCS for the peer STA
is implementation specific. If the most significant bit of the MCS field is set to 1, and the lower
7 bits indicate values of 5 to 10, or 12, the MCS should be interpreted as an Extended SC MCS,
with MCSs 9.1, 12.1, 12.2 ,12.3, 12.4, 12.5 or 12 6 respectively, for lower bits values of
5,6,7,8,9,10,12 respectively. The most significant bit of the MCS field is set to 1 only if the
receiving STA indicated support for the extended SC MCSs by adding the Extended SC MCS
capabilities to the DMG capability element.
Editor: Modify the text in P1325L61 (in subclause 10.7.9)
Replace 1<=MCS<=12 by 1<=MCS<=12.6
References:
All referenced sections and Tables are based on: Draft P802.11REVmc_D5.0.pdf
Submission
page 7
doc.: IEE