Nutating electromagnetic field transmitter

Abstract From the Canadian patent

A field (e.g. a magnetic field) which nutates about a pointing vector is used to both track or locate an object in addition to determining the relative orientation of this object. Apparatus for generating such a field includes mutually orthogonal coils and circuitry for supplying an unmodulated carrier, hereafter called DC signal to one, coil and an AC modulated carrier signal hereafter called AC, signal, to at least one (usually two) other coil such that, the maximum intensity vector of a magnetic field produced by the currents in the coils nutates about a means axis called the pointing vector direction of the field. The generated field is sensed in at least two orthogonal directions at …