Method and system for continuous position detection of moving parts in relation to each other

A method comprising:

• generating by a magnetic field source of a first magnetic field density of a first magnetic field with a first field polarization and, at a later time, generating a sequential second magnetic field density of a second magnetic field with a second field polarization, where the second field polarization differs from the first field polarization,
• determining said two different sequential magnetic field densities of said magnetic fields with the different field polarization generated by said one magnetic field source by a magnetometer sensor,
• determining a distance between the magnetic field source and magnetometer sensor based on a difference of the first magnetic field density and the sequential second magnetic field density determined by said magnetometer sensor, and
• compensating an offset drifting caused by a magnetic field environment based at least in part on the determined distance.

A mobile device comprising:

• a first part and a second part movable attached to said first part,
• a magnetic field source in said first part configured to generate a first magnetic field density of a first magnetic field with a first field polarization and to generate, at a later time, a sequential second magnetic field density of a second magnetic field with a second field polarization, where the second field polarization differs from the first field polarization,
• a magnetometer sensor in said second part configured to determine said two different sequential magnetic field densities of said magnetic fields with the different field polarization generated by said one magnetic field source, and
• a measurement unit configured to determine of a distance between the magnetic field source and magnetometer sensor based on a difference of the first magnetic field density and the sequential second magnetic field density determined by said magnetometer sensor, and thereby to determine the distance between the first and second part of the mobile device, and to compensate an offset drifting cuased by a magnetic field environment based at least in part on the determined distance between the first and second part of the mobile device.

A computer program product comprising machine readable instructions stored on a computer readable medium having computer executable components configured to control:

• a generation by a magnetic field source of a first magnetic field density of a first magnetic field with a first field polarization and, at a later time, generation of a sequential second magnetic field density of a second magnetic field with a second field polarization, where the second field polarization differs from the first field polarization,
• a determination of said two different sequential magnetic field densities of said magnetic fields with the different field polarization generated by said one magnetic field source by a magnetometer sensor,
• a determination of a distance between the magnetic field source and magnetometer sensor based on a difference of the first magnetic field density and the sequential second magnetic field density determined by said magnetometer sensor, and
• a compensation of an offset drifting caused by a magnetic field environment based at least in part on the determined distance.