Object Tracking Using Magnetic Field Sensing and Backscatter Transmissions

An object tracking device, comprising:

• a magnetic field sensor comprising one or more receiving coils;
• position tracking circuitry in communication with the magnetic field sensor, the position tracking circuitry configured to determine at least one field strength associated with at least one stationary magnetic field sensed at the one or more receiving coils in response to movement of the object tracking device relative to a surface remote from a source of the at least one stationary magnetic field, the position tracking circuitry configured to determine position information associated with a handwriting input to the object tracking device based at least in part on the at least one field strength;
• and
• a communication interface configured to transmit the position information to at least one remote computing device.

An object tracking system, comprising:

• a magnetic field transmitter comprising one or more transmitting coils configured to generate at least one stationary magnetic field;
• a plurality of object tracking devices, each object tracking device comprising a magnetic field sensor configured to sense the at least one stationary magnetic field in response to movement of the object tracking device relative to a surface remote from the magnetic field transmitter, each object tracking device comprising a communication interface configured to transmit position information based on a sensed strength of the at least one stationary magnetic field;
• and
• one or more computing devices configured to receive the position information from the communication interface and to initiate at least one action based on the position information.