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Machine translation
4. (WO2015191081) MOTION-AWARE MODULATION AND CODING SCHEME ADAPTATION
Note: Text based on automatic Optical Character Recognition processes. Please use the PDF version for legal matters

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.

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-f light (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.

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 transmitted between the device and the wireless AP.

13. A non-transitory computer readable medium having stored thereon machine readable instructions to provide motion-aware modulation and coding scheme (MCS) adaptation, the machine readable instructions, when executed, cause a processor to:

determine whether a device is static relative to a wireless access point (AP), or moving relative to the wireless AP; and

determine a rate probing interval, a frame retransmission limit, and a packet error ratio (PER) smoothing factor based on whether the device is determined to be static relative to the wireless AP, or moving relative to the wireless AP 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.

14. The non-transitory computer readable medium of claim 13, wherein the machine readable instructions to determine whether a device is static relative to a wireless AP, or moving relative to the wireless AP, further cause the processor to: send 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.

15. The non-transitory computer readable medium of claim 13, wherein the machine readable instructions to determine whether a device is static relative to a wireless AP, or moving relative to the wireless AP, further cause the processor to: evaluate changes in time-of-flight (ToF) for signals transmitted between the device and the wireless AP.