802.11ak Physical Rates
What are physical rates in 802.11ak?
Physical rates refer to the data transmission speeds supported at the PHY layer, inherited from base Wi-Fi standards.
Does 802.11ak define new physical rates?
No, it uses the physical rates defined by underlying standards like 802.11a/b/g/n/ac.
How does 802.11ak influence physical rate selection?
It provides measurement data that helps devices adapt rates based on channel conditions and interference.
What modulation schemes are used in 802.11ak physical rates?
Standard schemes like DSSS, OFDM, and those from 802.11n/ac depending on the device.
Can 802.11ak devices dynamically change rates?
Yes, devices use link and channel quality measurements to select optimal transmission rates.
How do channel load reports affect physical rates?
High channel load can prompt devices to lower rates to reduce retransmissions and interference.
Are multi-link transmissions supported at physical rate level?
Yes, 802.11ak supports multiple links, each potentially operating at different physical rates.
How is physical rate adaptation coordinated in multi-link scenarios?
Using measurement reports and link feedback to balance rates across links for efficiency.
Does 802.11ak support MIMO technologies affecting physical rates?
It inherits MIMO support from base standards, enabling higher rates through spatial streams.
What role does SNR play in determining physical rates in 802.11ak?
Higher Signal-to-Noise Ratio enables selection of higher modulation and coding schemes for faster rates.
How do devices handle rate fallback in poor conditions?
They reduce modulation rates or spatial streams to maintain reliable communication.
Is physical rate information reported to the AP in 802.11ak?
Yes, devices report link quality metrics to assist APs in resource and rate management.
Are there any new physical rate metrics introduced in 802.11ak?
No new rates, but enhanced measurement feedback helps optimize existing rates.
Can physical rates vary between different links in 802.11ak?
Yes, each link can use the most suitable rate based on local conditions.
How does interference impact physical rates in 802.11ak?
Increased interference typically forces lower rates to ensure data integrity.
Is physical rate control centralized or distributed in 802.11ak?
Both approaches can be used; APs may guide rates using reports, or clients adapt locally.
Does 802.11ak physical rate selection affect power consumption?
Yes, higher rates generally require more power but reduce transmission time.
How do physical rates in 802.11ak compare with previous standards?
They match or extend previous standard rates through multi-link and enhanced measurement capabilities.
Where can I find official documentation on 802.11ak physical rates?
Refer to the IEEE 802.11ak amendment and related PHY standards like 802.11n/ac documents.
Topics in this section,
Modulation |
BW |
Tsc |
FSP=BW/Tsc |
Tdata=1/FSP |
GI=Tdata/4 |
Symbol=Tdata+GI |
1/Symbol |
Bits/Symbol |
Code rate |
Usable sc |
Rate (Mbps) |
|---|---|---|---|---|---|---|---|---|---|---|---|
BPSK |
5 |
64 |
78.125 |
12.8 |
3.2 |
16 |
0.0625 |
1 |
1/2 |
48 |
1.5 |
BPSK |
5 |
64 |
78.125 |
12.8 |
3.2 |
16 |
0.0625 |
1 |
3/4 |
48 |
2.25 |
QPSK |
5 |
64 |
78.125 |
12.8 |
3.2 |
16 |
0.0625 |
2 |
1/2 |
48 |
3 |
QPSK |
5 |
64 |
78.125 |
12.8 |
3.2 |
16 |
0.0625 |
2 |
3/4 |
48 |
4.5 |
16-QAM |
5 |
64 |
78.125 |
12.8 |
3.2 |
16 |
0.0625 |
4 |
1/2 |
48 |
6 |
16-QAM |
5 |
64 |
78.125 |
12.8 |
3.2 |
16 |
0.0625 |
4 |
3/4 |
48 |
9 |
64-QAM |
5 |
64 |
78.125 |
12.8 |
3.2 |
16 |
0.0625 |
6 |
2/3 |
48 |
12 |
64-QAM |
5 |
64 |
78.125 |
12.8 |
3.2 |
16 |
0.0625 |
6 |
3/4 |
48 |
13.5 |
256-QAM |
5 |
64 |
78.125 |
12.8 |
3.2 |
16 |
0.0625 |
8 |
3/4 |
48 |
18 |
256-QAM |
5 |
64 |
78.125 |
12.8 |
3.2 |
16 |
0.0625 |
8 |
5/6 |
48 |
20 |
BPSK |
10 |
64 |
156.25 |
6.4 |
1.6 |
8 |
0.125 |
1 |
1/2 |
48 |
3 |
BPSK |
10 |
64 |
156.25 |
6.4 |
1.6 |
8 |
0.125 |
1 |
3/4 |
48 |
4.5 |
QPSK |
10 |
64 |
156.25 |
6.4 |
1.6 |
8 |
0.125 |
2 |
1/2 |
48 |
6 |
QPSK |
10 |
64 |
156.25 |
6.4 |
1.6 |
8 |
0.125 |
2 |
3/4 |
48 |
9 |
16-QAM |
10 |
64 |
156.25 |
6.4 |
1.6 |
8 |
0.125 |
4 |
1/2 |
48 |
12 |
16-QAM |
10 |
64 |
156.25 |
6.4 |
1.6 |
8 |
0.125 |
4 |
3/4 |
48 |
18 |
64-QAM |
10 |
64 |
156.25 |
6.4 |
1.6 |
8 |
0.125 |
6 |
2/3 |
48 |
24 |
64-QAM |
10 |
64 |
156.25 |
6.4 |
1.6 |
8 |
0.125 |
6 |
3/4 |
48 |
27 |
256-QAM |
10 |
64 |
156.25 |
6.4 |
1.6 |
8 |
0.125 |
8 |
3/4 |
48 |
36 |
256-QAM |
10 |
64 |
156.25 |
6.4 |
1.6 |
8 |
0.125 |
8 |
5/6 |
48 |
40 |
BPSK |
20 |
64 |
312.5 |
3.2 |
0.8 |
4 |
0.25 |
1 |
1/2 |
48 |
6 |
BPSK |
20 |
64 |
312.5 |
3.2 |
0.8 |
4 |
0.25 |
1 |
3/4 |
48 |
9 |
QPSK |
20 |
64 |
312.5 |
3.2 |
0.8 |
4 |
0.25 |
2 |
1/2 |
48 |
12 |
QPSK |
20 |
64 |
312.5 |
3.2 |
0.8 |
4 |
0.25 |
2 |
3/4 |
48 |
18 |
16-QAM |
20 |
64 |
312.5 |
3.2 |
0.8 |
4 |
0.25 |
4 |
1/2 |
48 |
24 |
16-QAM |
20 |
64 |
312.5 |
3.2 |
0.8 |
4 |
0.25 |
4 |
3/4 |
48 |
36 |
64-QAM |
20 |
64 |
312.5 |
3.2 |
0.8 |
4 |
0.25 |
6 |
2/3 |
48 |
48 |
64-QAM |
20 |
64 |
312.5 |
3.2 |
0.8 |
4 |
0.25 |
6 |
3/4 |
48 |
54 |
256-QAM |
20 |
64 |
312.5 |
3.2 |
0.8 |
4 |
0.25 |
8 |
3/4 |
48 |
72 |
256-QAM |
20 |
64 |
312.5 |
3.2 |
0.8 |
4 |
0.25 |
8 |
5/6 |
48 |
80 |
Reference links