A common method for providing user-input to an electronic system consists of tracking the position and motion of an object moved by the user and conveying this information to the electronic system. One embodiment of a positional tracking system for an object has an external and stationary magnetic-field emitter, a magnetic-field sensor which moves with the tracked object, and a microprocessor that compares magnetic-field intensity measurements taken by the sensor and compares it to magnetic-field characteristics defined for the external magnetic field emitter. A nonlinear equation solver, particle filter, or other method is used to determine the position of the sensor in the magnetic field. In this way the position of an object can be tracked using a single magnetic field emission source. This positional information can be combined with an inertial tracking system to mitigate drift errors.