The present invention leverages changes in the sensed strength of radio signals at different locations to determine a device's location. In one instance of the invention, inference procedures are used to process ambient commercial radio signals, to estimate a location or a probability distribution over...http://www.google.fr/patents/US7319877?utm_source=gb-gplus-shareBrevet US7319877 - Methods for determining the approximate location of a device from ambient signals
Methods for determining the approximate location of a device from ambient ...
