Apparatus and methods for adapting mobile unit to wireless lan

A method for operating a mobile unit, the mobile unit designed for use in a wireless network and located in a geographic region, the method comprising the steps of:

• scanning the frequency spectrum until an announcement message from an access point is detected;
• examining the frequency characteristics of said announcement message;
• comparing said frequency characteristics with a table in memory;
• determining the geographic region by matching said frequency characteristics with a geographic region listed in said table, said table also listing a frequency range for each geographic region;
• and
• adjusting the operating frequency range of the mobile unit to correspond with said frequency range corresponding to the geographic region.

A mobile unit for use in a wireless data communications network including one or more access points, wherein the frequency set of the mobile unit may be modified and the mobile unit includes:

• a receiver which receives in the mobile unit announcement messages broadcast by one or more of the access points, each of said messages having a unique frequency characteristic associated with the geographic location of the access point from which it was sent;
• a processing unit, which determines an allowable frequency set in the geographic region associated with the access point from which each of said messages was sent;
• and
• a frequency set adjuster, which adjusts the frequency set to send messages on said allowable frequency set.

A mobile unit for use in a wireless network, the mobile unit located in a geographic region and including:

• a frequency scanner, which scans the frequency spectrum until an announcement message from an access point is detected;
• a frequency characteristics detector, which examines the frequency characteristics of said announcement message;
• a comparator, which compares said frequency characteristics with a table in memory;
• a determiner, which determines the geographic region by matching said frequency characteristics with a geographic region listed in said table, said table also listing a frequency range for each geographic region;
• and
• a frequency adjuster, which adjusts the operating frequency range of the mobile unit to correspond with said frequency range corresponding to the geographic region.