Self-calibrating fluxgate magnetometer and methods of using

A continuously self-calibrating fluxgate magnetometer comprising:

• a ferromagnetic core;
• at least three pairs of mutually orthogonal drive coils surrounding the ferromagnetic core, at least one pair of drive coils corresponding to each principal axis of the magnetometer;
• drive electronics adapted to provide power to one or more of the drive coils or pairs of drive coils in order to generate a drive signal in at least one drive coil, the drive electronics comprising a function generator and a vector generation module, the function generator adapted to determine a waveform and frequency, the vector generation module adapted to determine a pattern for orientation, and the waveform, frequency, and pattern for orientation are adapted to be provided to one or more of the drive coils or pairs of drive coils to generate the drive signal and a measurement signal in at least one measurement coil, the at least one measurement coil adapted to measure a local magnetic field, and the measurement signal based at least in part on the drive signal interacting with the ferromagnetic core;
• and
• a virtual calibration spheroid comprising one or more of the drive signals in the at least one measurement coil,
• wherein the at least one measurement coil is adapted to measure a local minimum magnetic field and a local maximum magnetic field and the local minimum magnetic field correlates negatively to the Earth's local magnetic field and the local maximum magnetic field correlates positively to the Earth's local magnetic field and the vector generation module and calibration spheroid are adapted to calibrate the magnetometer by electrically, but not physically, rotating and/or selecting an axis of the magnetometer to be the measurement coil.

A continuously self-calibrating fluxgate magnetometer comprising:

• a ferromagnetic core;
• at least three pairs of mutually orthogonal drive coils surrounding the ferromagnetic core, at least one pair of drive coils corresponding to each principal axis of the magnetometer;
• drive electronics adapted to provide power to one or more of the drive coils or pairs of drive coils in order to generate a drive signal in at least one drive coil, the drive electronics comprising a function generator and a vector generation module, the function generator adapted to determine a waveform and frequency, the vector generation module adapted to determine a pattern for orientation, and the waveform, frequency, and pattern for orientation are adapted to be provided to one or more of the drive coils or pairs of drive coils to generate the drive signal and a measurement signal in at least one measurement coil, lithe at least one measurement coil adapted to measure a local magnetic field, and the measurement signal based at least in part on the drive signal interacting with the ferromagnetic core;
• a processor adapted to determine a local minimum in the magnetic field and a local maximum in the magnetic field and to generate a connecting vector to connect the local minimum and the local maximum magnetic fields, the connecting vector being indicative of Earth's local magnetic field;
• and
• a virtual calibration spheroid comprising one or more of the measurement signal(s) in the at least one measurement coil,
• wherein the vector generation module and calibration spheroid are adapted to calibrate the magnetometer by electrically, but not physically, rotating and/or selecting an axis of the magnetometer to be the measurement coil.