Reactive hybrid location determination method and apparatus

Abstract

A method is described of using the mobile device so as to control the drain of power from the power source of the mobile device, the mobile device having at least two location determination techniques having respective power drain characteristics, the method includes selecting the location determination technique having a lower power drain characteristic the greater the determined distance of the mobile device from a predetermined location or area, and selecting the location determination technique having the greater power drain characteristic the smaller the determined distance of the mobile device from a predetermined location or area. The method thus uses the least accurate technique when furthest away and the most accurate technique when closer to a predetermined location or area.

1 . A method for determining a location of a mobile device using a plurality of location determination techniques available to the mobile device each location determination technique having a respective accuracy of determination, the method comprising:
 a) calculating, at the mobile device, a first location of the mobile device using a first location determination technique, the first location determination technique having a first accuracy of determination, the first accuracy of determination associated with a first error distance;   b) determining a distance of the mobile device at the determined location to a predetermined location and adding the first error distance;   responsive to the determined distance including the first error distance being more than a first predetermined distance;
 c) calculating, at the mobile device, a second location of the mobile using a second location determination technique, the second location determination technique having a second accuracy of determination, the second accuracy of determination associated with a second error distance wherein the second accuracy of determination is greater than the first accuracy of determination; 
 d) determining a second distance of the mobile device at the determined to a predetermined location and adding including the second error distance. 
   
     
     
         2 . The method of  claim 1 , further comprising:
 responsive to the second determined distance including the second error distance being less than a second predetermined distance;   e) calculating, at the mobile device, a third location of the mobile device using a third location determination technique, the third location determination technique having a third accuracy of determination, the third accuracy of determination associated with a third error distance wherein the third accuracy of determination is greater than the second accuracy of determination;   f) determining a third distance of the mobile device at the determined to a predetermined location including the third error distance.   
     
     
         3 . The method of  claim 1 , a further comprising:
 adjusting the accuracy of determination for a location determination technique and the associated error distance according to the location determined in a prior location determination using that location determination technique.   
     
     
         4 . The method of  claim 1 , & further comprising:
 adjusting any one or more of the error distances by a marginal distance. 
 
     
     
         5 . The method of  claim 2 , & further comprising:
 adjusting the third error distances by a marginal distance. 
 
     
     
         6 . The method of  claim 1 , & further comprising:
 repeating step a) a predetermined times before performing step b). 
 
     
     
         7 . The method of  claim 1 , further comprising:
 repeating step c) a predetermined times before performing step d).   
     
     
         8 . The method of  claim 2 , further comprising:
 repeating step e) a predetermined times before performing step f).   
     
     
         9 . The method of  claim 1 , further comprising:
 determining a travel speed of the mobile device; and adjusting the first accuracy of determination based on the travel speed.   
     
     
         10 . The method of  claim 1 , further comprising:
 determining a travel speed of the mobile device; and adjusting the second accuracy of determination based on the travel speed.   
     
     
         11 . The method of  claim 2 , further comprising:
 determining a travel speed of the mobile device; and adjusting the third accuracy of determination based on the travel speed.   
     
     
         12 . The method of  claim 1 , wherein a frequency of location determination is determined based on the determined distance.