Motion-aware modulation and coding scheme adaptation

Patent metadata

Field	Value
Publication number	US-10284328-B2
Application number	US-201415307505-A
Country	US
Kind code	B2
Filing date	Jun 13, 2014
Priority date	Jun 13, 2014
Publication date	May 7, 2019
Grant date	May 7, 2019

Abstract

According to an example, motion-aware MCS adaptation may include determining whether a device is static relative to a wireless AP, moving towards the wireless AP, or moving away from the wireless AP. A device static rate probing interval, a device moving rate probing interval, first and second frame retransmission limits, a device static PER smoothing factor, and a device moving PER smoothing factor may be determined. In response to a determination that the device is static relative to the wireless AP, moving towards the wireless AP, or moving away from the wireless AP, an appropriate rate probing interval, an appropriate frame retransmission limit, and an appropriate PER smoothing factor may be used to determine a MCS value from a plurality of available MCS values to be used for transmitting data between the device and the wireless AP.

First claim

What is claimed is:

1. A method for motion-aware modulation and coding scheme (MCS) adaptation, the method comprising:
determining whether a device is static relative to a wireless access point (AP), moving towards the wireless AP, or moving away from the wireless AP;
determining a device static rate probing interval and a device moving rate probing interval to determine how frequently the wireless AP is to use a higher MCS value for data transmission to the device;
determining first and second frame retransmission limits to determine a number of times a failed frame transmission is to be retried with a same MCS value before using a lower MCS value, wherein the first frame retransmission limit is greater than the second frame retransmission limit;
determining a device static packet error ratio (PER) smoothing factor and a device moving PER smoothing factor to maintain a PER history for rate evaluation; and
in response to a determination that the device is static relative to the wireless AP, moving towards the wireless AP, or moving away from the wireless AP, using an appropriate rate probing interval of the determined rate probing intervals, an appropriate frame retransmission limit of the determined frame retransmission limits, and an appropriate PER smoothing factor of the determined PER smoothing factors to determine, by a processor, a MCS value from a plurality of available MCS values to be used for transmitting data between the device and the wireless AP, thereby using the determined MCS value that is a relatively best MCS value to minimize performance degradation.

2. The method of claim 1 , wherein determining whether a device is static relative to a wireless AP, moving towards the wireless AP, or moving away from the wireless AP further comprises:
determining a time-of-flight (ToF) for a signal transmitted between the device and the wireless AP.

3. The method of claim 1 , wherein determining whether a device is static relative to a wireless AP, moving towards the wireless AP, or moving away from the wireless AP further comprises:
sending a NULL data frame from one of the device and the wireless AP to determine a time-of-flight (ToF) for a signal transmitted between the device and the wireless AP based on receipt of an acknowledgement from the other one of the device and the wireless AP.

4. The method of claim 1 , wherein determining whether a device is static relative to a wireless AP, moving towards the wireless AP, or moving away from the wireless AP further comprises:
evaluating changes in time-of-flight (ToF) for signals transmitted between the device and the wireless AP.

5. The method of claim 1 , wherein in response to a determination that the device is static relative to the wireless AP, using an appropriate rate probing interval of the determined rate probing intervals, an appropriate frame retransmission limit of the determined frame retransmission limits, and an appropriate PER smoothing factor of the determined PER smoothing factors to determine a MCS value from a plurality of available MCS values to be used for transmitting data between the device and the wireless AP further comprises:
using the device static rate probing interval as the appropriate rate probing interval of the determined rate probing intervals, the second frame retransmission limit as the appropriate frame retransmission limit of the determined frame retransmission limits, and the device static PER smoothing factor as the appropriate PER smoothing factor of the determined PER smoothing factors to determine the MCS value from the plurality of available MCS values to be used for transmitting data between the device and the wireless AP.

6. The method of claim 1 , wherein in response to a determination that the device is moving towards the wireless AP, using an appropriate rate probing interval of the determined rate probing intervals, an appropriate frame retransmission limit of the determined frame retransmission limits, and an appropriate PER smoothing factor of the determined PER smoothing factors to determine a MCS value from a plurality of available MCS values to be used for transmitting data between the device and the wireless AP further comprises:
using the device moving rate probing interval as the appropriate rate probing interval of the determined rate probing intervals, the first frame retransmission limit as the appropriate frame retransmission limit of the determined frame retransmission limits, and the device moving PER smoothing factor as the appropriate PER smoothing factor of the determined PER smoothing factors to determine the MCS value from the plurality of available MCS values to be used for transmitting data between the device and the wireless AP.

7. The method of claim 1 , wherein in response to a determination that the device is moving away from the wireless AP, using an appropriate rate probing interval of the determined rate probing intervals, an appropriate frame retransmission limit of the determined frame retransmission limits, and an appropriate PER smoothing factor of the determined PER smoothing factors to determine a MCS value from a plurality of available MCS values to be used for transmitting data between the device and the wireless AP further comprises:
using the device static rate probing interval as the appropriate rate probing interval of the determined rate probing intervals, the second frame retransmission limit as the appropriate frame retransmission limit of the determined frame retransmission limits, and the device moving PER smoothing factor as the appropriate PER smoothing factor of the determined PER smoothing factors to determine the MCS value from the plurality of available MCS values to be used for transmitting data between the device and the wireless AP.

8. The method of claim 1 , wherein the device static rate probing interval is greater than the device moving rate probing interval.

9. The method of claim 1 , wherein the device static PER smoothing factor is greater than the device moving PER smoothing factor.

10. A motion-aware modulation and coding scheme (MCS) adaptation apparatus comprising:
a processor; and
a memory storing machine readable instructions that when executed by the processor cause the processor to:
determine whether a device is static relative to a wireless access point (AP), moving towards the wireless AP, or moving away from the wireless AP by determining time-of-flight (ToF) for signals transmitted between the device and the wireless AP;
determine a rate probing interval, a frame retransmission limit, and a packet error ratio (PER) smoothing factor; and
in response to a determination that the device is static relative to the wireless AP, moving towards the wireless AP, or moving away from the wireless AP, use the determined rate probing interval, the frame retransmission limit, and the PER smoothing factor to determine a MCS value from a plurality of available MCS values to be used for transmitting data between the device and the wireless AP, thereby using the determined MCS value that is a relatively best MCS value to minimize performance degradation.

11. The motion-aware MCS adaptation apparatus according to claim 10 , wherein the device is one of a smartphone and a tablet.

12. The motion-aware MCS adaptation apparatus according to claim 10 , wherein the machine readable instructions to determine whether a device is static relative to a wireless AP, moving towards the wireless AP, or moving away from the wireless AP by determining ToF for signals transmitted between the device and the wireless AP, when executed by the processor, further cause the processor to:
evaluate changes in the ToF for the signals transm

Assignees

• Hewlett Packard Entpr Dev Lp

Inventors

• Sen Souvik
• Sun Li

Classifications

• H04L1/1825

  Adaptation of specific ARQ protocol parameters according to transmission conditions · CPC title

• H04L5/006

  Quality of the received signal, e.g. BER, SNR, water filling · CPC title

• H04W84/12

  WLAN [Wireless Local Area Networks] · CPC title

• H04L1/0003 Primary

  by switching between different modulation schemes · CPC title

• H04L5/0055

  Physical resource allocation for ACK/NACK (for physical mapping arrangements in ARQ protocols H04L1/1861) · CPC title