System and method for setting link parameters in a WiFi link

Patent metadata

Field	Value
Publication number	US-11336388-B2
Application number	US-202016991987-A
Country	US
Kind code	B2
Filing date	Aug 12, 2020
Priority date	Feb 19, 2019
Publication date	May 17, 2022
Grant date	May 17, 2022

Abstract

A method for operating a link method includes estimating a plurality of throughputs, each throughput corresponding to one of a plurality of modulation and coding schemes, each one of the plurality of modulation and coding schemes corresponding to one of a plurality of combinations of spatial stream numbers and bandwidths, selecting a maximum throughput from the plurality of throughputs, and transmitting data according to a modulation and coding scheme, a spatial stream number, and a bandwidth corresponding to the maximum throughput.

First claim

What is claimed is:

1. A method for operating a link, the method comprising:
estimating a plurality of throughputs, each throughput corresponding to one of a plurality of modulation and coding schemes, each one of the plurality of modulation and coding schemes corresponding to one of a plurality of combinations of spatial stream numbers and bandwidths;
selecting a maximum throughput from the plurality of throughputs;
transmitting data according to a modulation and coding scheme, a spatial stream number, and a bandwidth corresponding to the maximum throughput; and
adjusting an estimated signal to interference and noise ratio for a first combination of the plurality of combinations of spatial stream numbers and bandwidths, which comprises:
transmitting a first quantity of data using the first combination;
receiving N1 acknowledgment signals, N1 being a nonnegative integer;
receiving N2 negative acknowledgment signals, N2 being a nonnegative integer; and
adjusting an estimated signal to interference and noise ratio for the first combination based on N1 and N2.

2. The method of claim 1 , wherein the adjusting of the estimated signal to interference and noise ratio comprises:
calculating an adjustment based on an estimated error rate, the adjustment being:
greater than zero when the estimated error rate is zero, and
less than zero when the estimated error rate is one; and

adding the adjustment to a previously estimated signal to interference and noise ratio for the first combination.

3. The method of claim 2 , wherein:
a number of spatial streams of a second combination of the plurality of combinations of spatial stream numbers and bandwidths exceeds that of the first combination, or a bandwidth of the second combination exceeds that of the first combination,
the estimating of a throughput, from among the plurality of throughputs, corresponding to the modulation and coding scheme of the second combination comprises adjusting an estimated signal to interference and noise ratio for the second combination, and
the adjusting of the estimated signal to interference and noise ratio for the second combination comprises adding, to a previously estimated signal to interference and noise ratio for the second combination, the adjustment based on the estimated error rate.

4. The method of claim 3 , wherein:
the previously estimated signal to interference and noise ratio for the first combination is a sum of:
a first reference signal to interference and noise ratio, and
an offset, and

the adding of the adjustment to the previously estimated signal to interference and noise ratio for the first combination comprises adding the adjustment to the offset.

5. The method of claim 4 , further comprising:
calculating the first reference signal to interference and noise ratio based on a signal to interference and noise ratio measured during reception of a beacon signal.

6. The method of claim 4 , wherein the calculating of the adjustment comprises:
determining whether:
the estimated error rate is less than a target error rate,
a current modulation coding scheme is equal to a maximum modulation coding scheme, and
the offset exceeds a first threshold; and

in response to determining that:
the estimated error rate is less than the target error rate,
the current modulation coding scheme is equal to the maximum modulation coding scheme, and
the offset exceeds the first threshold,

setting the adjustment to zero.

7. The method of claim 4 , wherein the calculating of the adjustment comprises:
determining whether:
the estimated error rate is greater than a target error rate,
a current modulation coding scheme is equal to a minimum modulation coding scheme, and
the offset is less than a second threshold; and

in response to determining that:
the estimated error rate is greater than the target error rate,
the current modulation coding scheme is equal to the minimum modulation coding scheme, and
the offset is less than the second threshold,

setting the adjustment to zero.

8. The method of claim 2 , wherein the adjustment is calculated according to
(1−PER)*snrStep/(1/targetPer−1)+PER*(−snrStep),
where PER is the estimated error rate, targetPer is a target error rate, and snrStep is an adjustment rate parameter.

9. The method of claim 8 , wherein the estimated error rate is calculated as N2/(N1+N2).

10. The method of claim 8 , wherein the target error rate is calculated based on a number of consecutive errors.

11. A system comprising a WiFi transmitter comprising a processing circuit, the processing circuit being configured to:
estimate a plurality of throughputs, each throughput corresponding to one of a plurality of modulation and coding schemes, each one of the plurality of modulation and coding schemes corresponding to one of a plurality of combinations of spatial stream numbers and bandwidths;
select a maximum throughput from the plurality of throughputs;
transmit data according to a modulation and coding scheme, a spatial stream number, and a bandwidth corresponding to the maximum throughput; and
adjusting an estimated signal to interference and noise ratio for a first combination of the plurality of combinations of spatial stream numbers and bandwidths, which comprises:
transmitting a first quantity of data using the first combination;
receiving N1 acknowledgment signals, N1 being a nonnegative integer;
receiving N2 negative acknowledgment signals, N2 being a nonnegative integer; and
adjusting an estimated signal to interference and noise ratio for the first combination based on N1 and N2.

12. The system of claim 11 , wherein the adjusting of the estimated signal to interference and noise ratio comprises:
calculating an adjustment based on an estimated error rate, the adjustment being:
greater than zero when the estimated error rate is zero, and
less than zero when the estimated error rate is one; and

adding the adjustment to a previously estimated signal to interference and noise ratio.

13. The system of claim 12 , wherein:
a number of spatial streams of a second combination of the plurality of combinations of spatial stream numbers and bandwidths, exceeds that of the first combination, or a bandwidth of the second combination exceeds that of the first combination, and
the estimating of a throughput, from among the plurality of throughputs, corresponding to the modulation and coding scheme of the second combination comprises adjusting an estimated signal to interference and noise ratio for the second combination,
the adjusting of the estimated signal to interference and noise ratio for the second combination comprises adding, to a previously estimated signal to interference and noise ratio for the second combination, the adjustment based on the estimated error rate.

14. The system of claim 13 , wherein:
the previously estimated signal to interference and noise ratio for the first combination is a sum of:
a first reference signal to interference and noise ratio, and
an offset; and

the adding of the adjustment to the previously estimated signal to interference and noise ratio for the first combination comprises adding the adjustment to the offset.

15. The system of claim 14 , wherein the processing circuit is further configured to calculate the first reference signal to interference and noise ratio based on a signal to interference and noise ratio measured during reception of a beacon signal.

16. The system of claim 14 , wherein the calculating of the adjustment comprises:
determining whether:
the estimated error rate is les

Assignees

• Samsung Electronics Co Ltd

Inventors

• Lee Wook Bong
• Ray Moumita
• Duan Ruchen

Classifications

• H04W52/241

  taking into account channel quality metrics, e.g. SIR, SNR, CIR or Eb/lo · CPC title

• H04L1/0625

  Transmitter arrangements · CPC title

• H04L1/203

  Details of error rate determination, e.g. BER, FER or WER · CPC title

• H04L1/1614

  using bitmaps · CPC title

• H04L1/0009

  by adapting the channel coding (H04L1/1812 takes precedence) · CPC title