Rapid acquisition and system selection of mobile wireless devices using a system map

Abstract

The present invention enhances service system selection by a mobile unit in a wireless communication system. The mobile unit determines its geographic position, and based on that position selects the proper service system. The geographic position may be determined using a global position system, deck reckoning, or estimated from a last known position. The distance of varying service systems from the mobile station can then be calculated and a service system selected based on this distance. The mobile station may also use the position information in combination with a database including position information of service systems to select the proper service system. The position information of the service systems can be included in the system selection database. The mobile station may also map service systems based on position information and service availability. The mobile station can then subsequently refer to these maps to estimate available service.

What is claimed is:  
     
         1 . A method of prioritizing a plurality of service systems in a wireless communication system comprising: 
 determining a reference location;    calculating a distance from the reference location to each of the plurality of service systems; and    prioritizing the plurality of service systems based on the distance from the reference location.    
     
     
         2 . The method of  claim 1 , wherein the reference location is determined using a global positioning system.  
     
     
         3 . The method of  claim 1 , wherein the reference location is determined using dead reckoning.  
     
     
         4 . The method of  claim 1 , wherein the reference location is a last known location of a mobile station.  
     
     
         5 . The method of  claim 1 , wherein the calculating step further comprises: 
 determining a drift term; and    adjusting the reference location based on the drift term.    
     
     
         6 . The method of  claim 5 , wherein the drift term is determined using the equation:  
       radius d =( t−t   last-system ) V   max    
       where t is a current time, t last-system  is a time that service was last available on a last known system, and V max  is a maximum expected velocity that a mobile station would travel during the period without service.  
     
     
         7 . The method of  claim 6 , wherein the distance is calculated using the equation:  
       
         
           
             
               
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                       radius 
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         8 . A method of prioritizing a plurality of service systems in a wireless communication system comprising: 
 determining a reference location; and    obtaining a prioritized list of service systems based on the reference location.    
     
     
         9 . The method of  claim 8 , wherein the reference location is determined using a global positioning system.  
     
     
         10 . The method of  claim 8 , wherein the reference location is determined using dead reckoning.  
     
     
         11 . The method of  claim 1 , wherein the prioritized list of service systems based on the reference location is obtained from stored data within a mobile station.  
     
     
         12 . The method of  claim 11 , wherein the data is stored in the system selection database.  
     
     
         13 . The method of  claim 12 , wherein the system selection database includes a position reference for each of the plurality of service systems.  
     
     
         14 . A mobile station for use in a wireless communication system comprising: 
 a position determination device; and    a database of system providers based on position information.    
     
     
         15 . The mobile station of  claim 14 , wherein the position determination device is a global positioning system.  
     
     
         16 . The mobile station of  claim 14 , wherein the database is included in the system selection database.  
     
     
         17 . The mobile station of  claim 14 , wherein the mobile station selects one of the system providers based on the database information.  
     
     
         18 . A mobile station for use in a wireless communication system comprising: 
 a position determination device;    a service detector which determines if service is available at any given position; and    memory locations for storing data regarding service availability for a plurality of locations, wherein the grouping of the memory locations provides a map of a service area showing service availability.    
     
     
         19 . The mobile station of  claim 18 , wherein the position determination device is a global positioning system.  
     
     
         20 . The mobile station of  claim 18 , wherein a grouping of memory locations containing position information can be converted to a formula defining a service area.  
     
     
         21 . The mobile station of  claim 18 , wherein each memory location stores both a latitude and a longitude of a position along with information indicating whether service was available at the position.  
     
     
         22 . A method of mapping a service system for a wireless communication system comprising: 
 establishing a reference location;    determining service availability for the reference location; and    storing the information on service availability for the reference location.    
     
     
         23 . The method of  claim 22 , wherein the reference location is established using a global positioning system.  
     
     
         24 . The method of  claim 22 , wherein the reference location is determined using dead reckoning.  
     
     
         25 . The method of  claim 22 , further comprising: 
 collecting data on service information for a plurality of reference locations; and    combining the data to provide a map of a service area showing service availability.    
     
     
         26 . The method of  claim 25 , further comprising converting the combined data into a formula defining a service area.  
     
     
         27 . The method of  claim 22 , wherein the stored information includes both a latitude and a longitude of the reference location along with information indicating whether service was available at the reference location.