Wlan scanning according to channel order representing decreasing relative prevalence of access point deployment

Abstract

A channel order that is specific to a population of access points is stored in a wireless local area network client device. The order of channels in the channel order represents the decreasing relative prevalence of access point deployment in the population. The wireless local area network client device scans for wireless local area networks according to the channel order.

What is claimed is: 
     
         1 . A method in a wireless local area network device, the method comprising:
 storing in the wireless local area network device an indication of a channel order for a plurality of channels, wherein the channel order is specific to a population of access points and is ordered by decreasing relative prevalence of access point deployment on each of the channels, and wherein the channels are partitioned, based on the channel order, into a first group of one or more channels on which more access points in the population are deployed, and N second groups of channels on which fewer access points in the population are deployed, wherein N is a whole number greater than or equal to two, and wherein each second group comprises one or more channels; and   scanning for wireless local area networks, in one or more scan sessions, according to a scanning scheme in which the channels in the first group are scanned once per scan session, and the channels in each of the N second groups are scanned once per N scan sessions,   initiating a subsequent scan session of the one or more scan sessions in the event that a current scan session does not locate any wireless local area networks.   
     
     
         2 . The method as claimed in  claim 1 , further comprising:
 waiting for a period of time between the current scan session and the subsequent scan session.   
     
     
         3 . The method as claimed in  claim 2 , further comprising:
 increasing the period of time with each successive scan session.   
     
     
         4 . The method as claimed in  claim 2 , further comprising:
 entering a reduced power state during the period of time.   
     
     
         5 . The method as claimed in  claim 1 , wherein the population is a general population of access points worldwide, or a general population of access points in a single regulatory domain, or a general population of access points in a single market, or a general population of access points in a single country. 
     
     
         6 . The method as claimed in  claim 1 , wherein scanning on the channels in the first group comprises:
 in the event that there is more than one channel in the first group, scanning on the channels in the first group according to an order of decreasing relative prevalence of access point deployment on each of the channels in the first group.   
     
     
         7 . The method as claimed in  claim 1 , wherein scanning on the channels in any one of the N second groups comprises:
 in the event that there is more than one channel in the one second group, scanning on the channels in the one second group according to an order of decreasing relative prevalence of access point deployment on each of the channels in the one second group.   
     
     
         8 . A device comprising:
 a processor;   a wireless local area network interface coupled to the processor, the wireless local area network interface comprising a wireless local area network controller and a radio;   an antenna coupled to the radio; and   a memory coupled to the processor,   the memory arranged to store an indication of a channel order for a plurality of channels, wherein the channel order is specific to a population of access points and is ordered by decreasing relative prevalence of access point deployment on each of the channels, and wherein the channels are partitioned, based on the channel order, into a first group of one or more channels on which more access points in the population are deployed, and N second groups of channels on which fewer access points in the population are deployed, wherein N is a whole number greater than or equal to two, and wherein each second group comprises one or more channels; and   the memory further arranged to store executable code which, when executed by the processor, controls the wireless local area network controller:
 to scan for wireless local area networks, in one or more scan sessions, according to a scanning scheme in which the channels in the first group are scanned once per scan session, and the channels in each of the N second groups are scanned once per N scan sessions; and 
 to initiate a subsequent scan session of the one or more scan sessions in the event that a current scan session does not locate any wireless local area networks. 
   
     
     
         9 . The device as claimed in  claim 8 , wherein the executable code, when executed by the processor, further controls the wireless local area network controller:
 to wait for a period of time between the current scan session and the subsequent scan session.   
     
     
         10 . The device as claimed in  claim 9 , wherein the executable code, when executed by the processor, further controls the wireless local area network controller:
 to increase the period of time with each successive scan session.   
     
     
         11 . The device as claimed in  claim 9 , wherein the executable code, when executed by the processor, controls the device:
 to enter a reduced power state during the period of time.   
     
     
         12 . The device as claimed in  claim 8 , wherein the population is a general population of access points worldwide, or a general population of access points in a single regulatory domain, or a general population of access points in a single market, or a general population of access points in a single country. 
     
     
         13 . The device as claimed in  claim 8 , wherein scanning on the channels in the first group comprises:
 in the event that there is more than one channel in the first group, scanning on the channels in the first group according to an order of decreasing relative prevalence of access point deployment on each of the channels in the first group.   
     
     
         14 . The device as claimed in  claim 8 , wherein scanning on the channels in any one of the N second groups comprises:
 in the event that there is more than one channel in the one second group, scanning on the channels in the one second group according to an order of decreasing relative prevalence of access point deployment on each of the channels in the one second group.   
     
     
         15 . A non-transitory computer readable medium storing computer executable instructions which, when executed by a processor of a wireless local area network device cause the device to be operable:
 to arrange for a memory of the wireless local area network device that is coupled to the processor to store an indication of a channel order for a plurality of channels, wherein the channel order is specific to a population of access points and is ordered by decreasing relative prevalence of access point deployment on each of the channels, and wherein the channels are partitioned, based on the channel order, into a first group of one or more channels on which more access points in the population are deployed, and N second groups of channels on which fewer access points in the population are deployed, wherein N is a whole number greater than or equal to two, and wherein each second group comprises one or more channels; and   to control a wireless local area network interface coupled to the processor:
 to scan for wireless local area networks, in one or more scan sessions, according to a scanning scheme in which the channels in the first group are scanned once per scan session, and the channels in each of the N second groups are scanned once per N scan sessions; and 
 to initiate a subsequent scan session of the one or more scan sessions in the event that a current scan session does not locate any wireless local area networks. 
   
     
     
         16 . The non-transitory computer readable medium as claimed in  claim 15 , wherein the computer executable instructions, when executed by the processor, further control the wireless local area network interface:
 to wait for a period of time between the current scan session and the subsequent scan session.   
     
     
         17 . The non-transitory computer readable medium as claimed in  claim 16 , wherein the computer executable instructions, when executed by the processor, further control the wireless local area network interface:
 to increase the period of time with each successive scan session.   
     
     
         18 . The non-transitory computer readable medium as claimed in  claim 16 , wherein the computer executable instructions, when executed by the processor, control the wireless local area network device:
 to enter a reduced power state during the period of time.   
     
     
         19 . The non-transitory computer readable medium as claimed in  claim 15 , wherein the population is a general population of access points worldwide, or a general population of access points in a single regulatory domain, or a general population of access points in a single market, or a general population of access points in a single country. 
     
     
         20 . The non-transitory computer readable medium as claimed in  claim 15 , wherein scanning on the channels in the first group comprises:
 in the event that there is more than one channel in the first group, scanning on the channels in the first group according to an order of decreasing relative prevalence of access point deployment on each of the channels in the first group.   
     
     
         21 . The non-transitory computer readable medium as claimed in  claim 15 , wherein scanning on the channels in any one of the N second groups comprises:
 in the event that there is more than one channel in the one second group, scanning on the channels in the one second group according to an order of decreasing relative prevalence of access point deployment on each of the channels in the one second group.