Patent ID: 7245215

Claim:
A position tracking device for use in position tracking system, wherein the position tracking device is associated with a mobile object to be tracked by the position tracking system such that the position tracking device moves with the mobile object, the position tracking device comprising: an inertial sensor assembly; a reference position receiver; and a high resolution module in communication with the inertial sensor assembly and the reference position receiver, wherein the high resolution module is for computing the location of the mobile object in real-time based on a combination of input from the inertial sensor assembly and a reference position signal received by the reference position receiver when the mobile object is located in a first area requiring high position resolution, wherein the high resolution module is for computing the location of the object by: detecting a current mode of movement for the mobile object based on the input from the inertial sensor assembly and historical information about the location of the mobile object; determining a first estimated position of the mobile object based at least on a motion model for the current mode of movement for the mobile object: determining a second estimated position of mobile object based on the input from the inertial sensor assembly and the historical information about the location of the mobile object; and estimating a real-time location of the mobile object based on the first and second estimated positions.