Mobile device utilizing time of flight for personal security and localization

Abstract

A mobile device case for functional connection and physical attachment to a mobile device, the mobile device case comprises an application adapted to run in the mobile device and a cradle configured for removable attachment with the mobile device, the cradle comprising a controller capable of functional connection with the application, where the cradle is adapted to protect the mobile device while attached to the mobile device and the cradle is adapted to functionally pair with the application to create at least a portion of a mesh network.

What is claimed herein is:  
     
       1. A method for determining the location of a frequency receiver device from a frequency originator device of a known location, said method comprising:
 (a) synchronizing a clock of said frequency originator device with a clock of the frequency receiver device; 
 (b) receiving by said frequency receiver device a directional message containing a broadcast time at which said directional message is broadcasted at an orientation from the frequency originator device; 
 (c) calculating a time of flight of said directional message by calculating the difference between a receive time at which said directional message is received by said frequency receiver device and said broadcast time and determining the distance between the frequency originator device and said frequency receiver device by multiplying said time of flight of said directional message by the speed of said directional message; 
 (d) determining the frequency of said directional message and determining said orientation by looking up a table containing orientations of messages about the frequency originator device with respect to the frequency of the messages; and 
 (e) determining the location of said frequency receiver device based on said orientation and the known location of the frequency originator device. 
 
     
     
       2. The method of  claim 1 , wherein the frequency originator device comprises a device selected from the group consisting of a long range acoustic device (LRAD) and a phased array speaker system. 
     
     
       3. The method of  claim 1 , wherein at least one of said frequency receiver device and said frequency originator device is a mobile device. 
     
     
       4. The method of  claim 1 , wherein said frequency receiver device and the frequency originator device are capable of underwater operation. 
     
     
       5. The method of  claim 1 , wherein the known location is movable. 
     
     
       6. The method of  claim 1 , wherein said synchronizing step is performed via a mechanism selected from the group consisting of a peer-to-peer arrangement and a web server arrangement.