Scan channel reduction to improve wi-fi system power

Patent metadata

Field	Value
Publication number	US-2016183181-A1
Application number	US-201514619675-A
Country	US
Kind code	A1
Filing date	Feb 11, 2015
Priority date	Dec 18, 2014
Publication date	Jun 23, 2016
Grant date	—

Abstract

A system and method are disclosed that may selectively switch a station's association from a first AP to a second AP based, at least in part, on whether an indication of first RSSI values for the first AP is greater than an indication of second RSSI values for the second AP by more than a difference value. For some embodiments, the difference value may be dynamically adjusted based, at least in part, on the first RSSI values, on a connection history of the station, and/or on a user selection.

First claim

What is claimed is:

1 . A method for selectively switching a mobile station's association from a first access point (AP) to a second AP, the method performed by the mobile station (STA) and comprising:
determining a number of first received signal strength indicator (RSSI) values for the first AP; determining a number of second RSSI values for the second AP; comparing an indication of the first RSSI values and an indication of the second RSSI values; if the indication of the second RSSI values is greater than the indication of the first RSSI values by more than a difference value, disassociating from the first AP and associating with the second AP; if the indication of the second RSSI values is not greater than the indication of the first RSSI values by more than the difference value, maintaining the association with the first AP; and dynamically adjusting the difference value based, at least in part, on the number of first RSSI values by:
increasing the difference value if a moving average of the first RSSI values indicates that the first RSSI values are increasing over time; and
decreasing the difference value if the moving average of the first RSSI values indicates that the first RSSI values are decreasing over time.

2 . The method of claim 1 , wherein the indication of the first RSSI values comprises an average of the first RSSI values, and the indication of the second RSSI values comprises an average of the second RSSI values.

3 . The method of claim 2 , wherein dynamically adjusting the difference value further comprises:
increasing the difference value if the STA has been associated with the first AP for more than a predetermined time period; and decreasing the difference value if the STA has not been associated with the first AP for more than the predetermined time period.

4 . The method of claim 1 , wherein the difference value is based, at least in part, on a user selection of a first mode or a second mode.

5 . The method of claim 4 , wherein:
if the user selection is the first mode, setting the difference value to a relatively high value; and if the user selection is the second mode, setting the difference value to a relatively low value.

6 . A mobile station (STA) that selectively switches its association from a first access point (AP) to a second AP, the STA comprising:
means for determining a number of first received signal indicator (RSSI) values for the first AP; means for determining a number of second RSSI values for the second AP; means for comparing an indication of the first RSSI values and an indication of the second RSSI values; means for disassociating from the first AP and associating with the second AP if the indication of the second RSSI values is greater than the indication of the first RSSI values by more than a difference value; means for maintaining the association with the first AP if the indication of the second RSSI values is not greater than the indication of the first RSSI values by more than the difference value; and means for dynamically adjusting the difference value based, at least in part, on the number of first RSSI values, means for dynamically adjusting is to:
increase the difference value if a moving average of the first RSSI values indicates that the first RSSI values are increasing over time; and
decrease the difference value if the moving average of the first RSSI values indicates that the first RSSI values are decreasing over time.

7 . The mobile station of claim 6 , wherein the indication of the first RSSI values comprises an average of the first RSSI values, and the indication of the second RSSI values comprises an average of the second RSSI values.

8 . The mobile station of claim 6 , wherein the means for dynamically adjusting the difference value is to further:
increase the difference value if the STA has been associated with the first AP for more than a predetermined time period; and decrease the difference value if the STA has not been associated with the first AP for more than the predetermined time period.

9 . The mobile station of claim 6 , wherein the difference value is based, at least in part, on a user selection of a first mode or a second mode.

10 . The mobile station of claim 9 , further comprising:
means for setting the difference value to a relatively high value if the user selection is the first mode; and means for setting the difference value to a relatively low value if the user selection is the second mode.

11 . A mobile station (STA) that selectively switches its association from a first access point (AP) to a second AP, the STA comprising:
a processor; and a memory storing instructions that, when executed by the processor, cause the STA to perform operations comprising:
determining a number of first received signal indicator (RSSI) values for the first AP;
determining a number of second RSSI values for the second AP;
comparing an indication of the first RSSI values and an indication of the second RSSI values;
disassociating from the first AP and associating with the second AP if the indication of the second RSSI values is greater than the indication of the first RSSI values by more than a difference value;
maintaining the association with the first AP if the indication of the second RSSI values is not greater than the indication of the first RSSI values by more than the difference value; and
dynamically adjust the difference value based, at least in part, on the number of first RSSI values, wherein execution of the instructions to dynamically adjust the difference value causes the STA to perform operations further comprising:
increasing the difference value if a moving average of the first RSSI values indicates that the first RSSI values are increasing over time; and
decreasing the difference value if the moving average of the first RSSI values indicates that the first RSSI values are decreasing over time.

12 . The mobile station of claim 11 , wherein the indication of the first RSSI values comprises an average of the first RSSI values, and the indication of the second RSSI values comprises an average of the second RSSI values.

13 . The mobile station of claim 11 , wherein execution of the instructions to dynamically adjust the difference value causes the STA to:
increase the difference value if the STA has been associated with the first AP for more than a predetermined time period; and decrease the difference value if the STA has not been associated with the first AP for more than the predetermined time period.

14 . The mobile station of claim 11 , wherein the difference value is based, at least in part, on a user selection of a first mode or a second mode.

15 . The mobile station of claim 14 , wherein execution of the instructions causes the STA to perform operations further comprising:
setting the difference value to a relatively high value if the user selection is the first mode; and setting the difference value to a relatively low value if the user selection is the second mode.

16 . A non-transitory computer-readable storage medium storing one or more programs containing instructions that, when executed by a mobile station (STA) to selectively switch its association from a first access point (AP) to a second AP, cause the STA to:
determine a number of first received signal indicator (RSSI) values for the first AP; determine a number of second RSSI values for the second AP; compare an indication of the first RSSI values and an indication of the second RSSI values; disassociate from the first AP and associating with the second AP

Assignees

• Qualcomm Inc

Inventors

• Lee Jin Won
• Teague Edward Harrison

Classifications

• H04B17/318

  Received signal strength · CPC title

• H04W48/16

  Discovering, processing access restriction or access information · CPC title

• H04W48/20 Primary

  Selecting an access point · CPC title

• H04B17/26

  using historical data, averaging values or statistics · CPC title

• H04W36/008375

  based on historical data · CPC title