System and method for improving success rate of beacon frame reception in wireless networks

1 . A method, comprising:

determining, by one or more processors of a client station (STA), a reference time interval based on a difference between a second transmission time of a second beacon frame and a first transmission time of a first beacon frame;

determining, by the one or more processors of the STA, an STA time interval based on a difference between a second receipt time of the second beacon frame and a first receipt time of the first beacon frame;

determining, by the one or more processors of the STA, a delta REF-STA time value based on the determined reference time interval and the determined STA time interval;

determining, by the one or more processors of the STA, a normalized delta REF-STA time value based on the delta REF-STA time value, a predetermined beacon interval, and the reference time interval;

determining, by the one or more processors of the STA, a target beacon transmission time (TBTT) of a subsequent beacon frame based on a transmission time of a current beacon frame and a predetermined beacon interval;

determining, by the one or more processors of the STA, an STA wake-up time based on the TBTT of the subsequent beacon frame and the normalized delta REF-STA time value; and

waking, by the one or more processors of the STA, the STA from a power-saving mode at the STA wake-up time to prepare for receiving the subsequent beacon frame.

2 . The method of claim 1 , wherein the normalized delta REF-STA time value is determined by multiplying the delta REF-STA time value by the predetermined beacon interval and dividing by the reference time interval.

3 . The method of claim 1 , wherein the normalized delta REF-STA time value is a first normalized delta REF-STA time value; and the method further comprises:

receiving one or more additional beacon frames;

for each beacon frame of the one or more additional beacon frames,

measuring a receipt time of the each beacon frame of the one or more additional beacon frames according to an STA's clock;

determining an additional reference time interval based on a difference between a transmission time of the each beacon frame of the one or more additional beacon frames and a transmission time of a preceding beacon frame;

determining an additional STA time interval based on a difference between the receipt time of the each beacon frame of the one or more additional beacon frames and a receipt time of the preceding beacon frame;

determining an additional delta REF-STA time value based on a difference between the additional reference time interval and the additional STA time interval; and

determining an additional normalized delta REF-STA time value based on the additional delta REF-STA time value, a predetermined beacon interval, and the additional reference time interval, resulting in one or more additional normalized delta REF-STA time values; and

selecting an optimal normalized delta REF-STA time value from the one or more additional normalized delta REF-STA time values and the first normalized delta REF-STA time value; and

wherein the STA wake-up time is determined based on the TBTT of the subsequent beacon frame and the optimal normalized delta REF-STA time value.

4 . The method of claim 3 , further comprising:

determining the transmission time of the each beacon frame of the one or more additional beacon frames based on a timing synchronization function (TSF) value of the each beacon frame of the one or more additional beacon frames; and

wherein the additional reference time interval is determined based on a difference between the TSF value of the each beacon frame of the one or more additional beacon frames and a TSF value of a preceding beacon frame.

5 . The method of claim 3 , wherein the optimal normalized delta REF-STA time value is a maximum value among the one or more additional normalized delta REF-STA time values and the first normalized delta REF-STA time value.

6 . The method of claim 3 , wherein the optimal normalized delta REF-STA time value is zero based on the one or more additional normalized delta REF-STA time values and the first normalized delta REF-STA time value comprising at least one negative number.

7 . The method of claim 3 , wherein:

the additional reference time intervals are first additional reference time intervals;

the additional STA time intervals are first additional STA time intervals;

the additional delta REF-STA time values are first additional delta REF-STA time values;

the additional normalized delta REF-STA time values are first additional normalized delta REF-STA time values; and

the optimal normalized delta REF-STA time value is a first optimal normalized delta REF-STA time value; and

the method further comprising:

detecting a predetermined number of consecutive failures to receive beacon frames from an access point;

re-initiating following operations in response to detecting the predetermined number of consecutive failures to receive beacon frames from the access point:

receiving at least two additional beacon frames;

for each beacon frame of the at least two additional beacon frames,

measuring a receipt time of the each beacon frame of the at least two additional beacon frames according to the STA's clock;

determining a second additional reference time interval based on a difference between a transmission time of the each beacon frame of the at least two additional beacon frames and a transmission time of a preceding beacon frame;

determining a second additional STA time interval based on a difference between the receipt time of the each beacon frame of the at least two additional beacon frames and a receipt time of the preceding beacon frame;

determining a second additional delta REF-STA time value based on a difference between the second additional reference time interval and the second additional STA time interval; and

determining a second additional normalized delta REF-STA time value based on the second additional delta REF-STA time value, a predetermined beacon interval, and the second additional reference time interval, resulting in one or more second additional normalized delta REF-STA time values; and

selecting a second optimal normalized delta REF-STA time value from the one or more second additional normalized delta REF-STA time values and the first normalized delta REF-STA time value; and

wherein the STA wake-up time is determined based on the TBTT of the subsequent beacon frame and the second optimal normalized delta REF-STA time value.

8 . The method of claim 7 , further comprising:

determining the transmission time of the each beacon frame of the at least two additional beacon frames based on a TSF value of the each beacon frame of the at least two additional beacon frames; and

wherein the second additional reference time interval is determined based on a difference between the TSF value of the each beacon frame of the at least two additional beacon frames and a TSF value of a preceding beacon frame.

9 . The method of claim 1 , wherein the TBTT of the subsequent beacon frame is determined based on the receipt time of the current beacon frame and the predetermined beacon interval comprises:

determining a current cycle number by performing a floor division of the transmission time of the current beacon frame by the predetermined beacon interval; and

determining the TBTT of the subsequent beacon frame based on the current cycle number and the predetermined beacon interval.

10 . A client station comprising:

one or more processors; and

a non-transitory memory storing instructions that, when executed by the one or more processors, configure the client station (STA) to:

determine a reference time interval based on a difference between a second transmission time of a second beacon frame and a first transmission time of a first beacon frame;

determine an STA time interval based on a difference between a second receipt time of the second beacon frame and a first receipt time of the first beacon frame;

determine a delta REF-STA time value based on the determined reference time interval and the determined STA time interval;

determine a normalized delta REF-STA time value based on the delta REF-STA time value, a predetermined beacon interval, and the reference time interval;

determine a target beacon transmission time (TBTT) of a subsequent beacon frame based on a TSF value of a current beacon frame and a predetermined beacon interval;

determine an STA wake-up time based on the TBTT of the subsequent beacon frame and the normalized delta REF-STA time value; and

wake the STA from a power-saving mode at the STA wake-up time to prepare for receiving the subsequent beacon frame.

11 . The client station of claim 10 , wherein the normalized delta REF-STA time value is determined by multiplying the delta REF-STA time value by the predetermined beacon interval and dividing by the reference time interval.

12 . The client station of claim 10 , wherein the normalized delta REF-STA time value is a first normalized delta REF-STA time value; and the client station is further configured to:

receive one or more additional beacon frames;

for each beacon frame of the one or more additional beacon frames,

measure a receipt time of the each beacon frame of the one or more additional beacon frames according to an STA's clock;

determine an additional reference time interval based on a difference between a transmission time of the each beacon frame of the one or more additional beacon frames and a transmission time of a preceding beacon frame;

determine an additional STA time interval based on a difference between the receipt time of the each beacon frame of the one or more additional beacon frames and a receipt time of the preceding beacon frame;

determine an additional delta REF-STA time value based on a difference between the additional reference time interval and the additional STA time interval; and

determine an additional normalized delta REF-STA time value based on the additional delta REF-STA time value, a predetermined beacon interval, and the additional reference time interval, resulting in one or more additional normalized delta REF-STA time values; and

select an optimal normalized delta REF-STA time value from the one or more additional normalized delta REF-STA time values and the first normalized delta REF-STA time value; and

wherein the STA wake-up time is determined based on the TBTT of the subsequent beacon frame and the optimal normalized delta REF-STA time value.

13 . The client station of claim 12 , wherein the client station is further configured to:

determine the transmission time of the each beacon frame of the one or more additional beacon frames based on a timing synchronization function (TSF) value of the each beacon frame of the one or more additional beacon frames; and

wherein the additional reference time interval is determined based on a difference between the TSF value of the each beacon frame of the one or more additional beacon frames and a TSF value of a preceding beacon frame.

14 . The client station of claim 12 , wherein the optimal normalized delta REF-STA time value is a maximum value among the one or more additional normalized delta REF-STA time values and the first normalized delta REF-STA time value.

15 . The client station of claim 12 , wherein the optimal normalized delta REF-STA time value is zero based on the one or more additional normalized delta REF-STA time values and the first normalized delta REF-STA time value comprising at least one negative number.

16 . The client station of claim 12 , wherein:

the additional reference time intervals are first additional reference time intervals;

the additional STA time intervals are first additional STA time intervals;

the additional delta REF-STA time values are first additional delta REF-STA time values;

the additional normalized delta REF-STA time values are first additional normalized delta REF-STA time values; and

the optimal normalized delta REF-STA time value is a first optimal normalized delta REF-STA time value; and

the client station is further configured to:

detect a predetermined number of consecutive failures to receive beacon frames from an access point;

re-initiate following operations in response to detecting the predetermined number of consecutive failures to receive beacon frames from the access point:

receive at least two additional beacon frames;

for each beacon frame of the at least two additional beacon frames,

measure a receipt time of the each beacon frame of the at least two additional beacon frames according to the STA's clock;

determine a second additional reference time interval based on a difference between a transmission time of the each beacon frame of the at least two additional beacon frames and a transmission time of a preceding beacon frame;

determine a second additional STA time interval based on a difference between the receipt time of the each beacon frame of the at least two additional beacon frames and a receipt time of the preceding beacon frame;

determine a second additional delta REF-STA time value based on a difference between the second additional reference time interval and the second additional STA time interval; and

determine a second additional normalized delta REF-STA time value based on the second additional delta REF-STA time value, a predetermined beacon interval, and the second additional reference time interval, resulting in one or more second additional normalized delta REF-STA time values; and

select a second optimal normalized delta REF-STA time value from the one or more second additional normalized delta REF-STA time values and the first normalized delta REF-STA time value; and

wherein the STA wake-up time is determined based on the TBTT of the subsequent beacon frame and the second optimal normalized delta REF-STA time value.

17 . The client station of claim 16 , wherein the client station is further configured to:

determine the transmission time of the each beacon frame of the at least two additional beacon frames based on a TSF value of the each beacon frame of the at least two additional beacon frames; and

wherein the second additional reference time interval is determined based on a difference between the TSF value of the each beacon frame of the at least two additional beacon frames and a TSF value of a preceding beacon frame.

18 . A non-transitory computer-readable storage medium including instructions that when executed by one or more processors of a client station (STA), cause the client station to:

determine a reference time interval based on a difference between a second transmission time of a second beacon frame and a first transmission time of a first beacon frame;

determine an STA time interval based on a difference between a second receipt time of the second beacon frame and a first receipt time of the first beacon frame;

determine a delta REF-STA time value based on the determined reference time interval and the determined STA time interval;

determine a normalized delta REF-STA time value based on the delta REF-STA time value, a predetermined beacon interval, and the reference time interval;

determine a target beacon transmission time (TBTT) of a subsequent beacon frame based on a TSF value of a current beacon frame and a predetermined beacon interval;

determine an STA wake-up time based on the TBTT of the subsequent beacon frame and the normalized delta REF-STA time value; and

wake the STA from a power-saving mode at the STA wake-up time to prepare for receiving the subsequent beacon frame.

19 . The non-transitory computer-readable storage medium of claim 18 , wherein the normalized delta REF-STA time value is determined by multiplying the delta REF-STA time value by the predetermined beacon interval and dividing by the reference time interval.

20 . The non-transitory computer-readable storage medium of claim 18 , wherein the normalized delta REF-STA time value is a first normalized delta REF-STA time value and the instructions further cause the client station to:

receive one or more additional beacon frames;

for each beacon frame of the one or more additional beacon frames,

measure a receipt time of the each beacon frame of the one or more additional beacon frames according to an STA's clock;

determine an additional reference time interval based on a difference between a transmission time of the each beacon frame of the one or more additional beacon frames and a transmission time of a preceding beacon frame;

determine an additional STA time interval based on a difference between the receipt time of the each beacon frame of the one or more additional beacon frames and a receipt time of the preceding beacon frame;

determine an additional delta REF-STA time value based on a difference between the additional reference time interval and the additional STA time interval; and

determine an additional normalized delta REF-STA time value based on the additional delta REF-STA time value, a predetermined beacon interval, and the additional reference time interval, resulting in one or more additional normalized delta REF-STA time values; and

select an optimal normalized delta REF-STA time value from the one or more additional normalized delta REF-STA time values and the first normalized delta REF-STA time value; and

wherein the STA wake-up time is determined based on the TBTT of the subsequent beacon frame and the optimal normalized delta REF-STA time value.