METHOD AND SYSTEM FOR MOBILE DEVICE LOCALIZATION IN MAGNETIC FIELDS
A method and system of localizing a mobile device having a processor and a memory. The method comprises localizing the mobile device, using the processor and the memory, along a sequence of positions describing a route being traversed in an indoor facility based on a set of data fusion inputs, detecting, based on magnetic field data from a magnetic field sensor device coupled to the processor of the mobile device, in conjunction with map feature data of the indoor facility, existence of a distortive magnetic field, and using the processor, localizing the mobile device based on a subset of the set of data fusion inputs.
1 . A method for localizing a mobile device having a processor and a memory, the method comprising:
localizing the mobile device, using the processor and the memory, along a sequence of positions describing a route being traversed in an indoor facility based on a set of data fusion inputs;
detecting, based on magnetic field data from a magnetic field sensor device coupled to the processor of the mobile device, in conjunction with map feature data of the indoor facility, existence of a distortive magnetic field; and
using the processor, localizing the mobile device based on a subset of the set of data fusion inputs.
2 . The method of claim 1 wherein the set of data fusion inputs includes wireless signal data, inertial sensor data, and the magnetic field data of the magnetic field sensor.
3 . The method of claim 2 wherein the set of data fusion inputs further includes at least one of barometric data and optical line of sight data.
4 . The method of claim 2 wherein the subset of the set of data fusion inputs excludes the magnetic field data.
5 . The method of claim 2 wherein the magnetic field data includes at least one of a magnetic field strength, an orientation and a magnetic dip angle.
6 . The method of claim 2 wherein the magnetic sensor device comprises a magnetometer of the mobile device.
7 . The method of claim 6 further comprising deactivating the magnetometer during the existence of the distortive magnetic field;
8 . The method of claim 2 wherein the map feature data is accessed from a localization fingerprint database for the indoor facility.
9 . The method of claim 1 further comprising detecting a transition out of the distortive magnetic field based on the map feature data.
10 . The method of claim 9 further comprising reverting to localizing the mobile device based on the set of data fusion inputs.
11 . A mobile device comprising:
a processor;
a memory storing a set of instructions, the instructions executable in the processor to:
localize the mobile device, using the processor and the memory, along a sequence of positions describing a route being traversed in an indoor facility based on a set of data fusion inputs;
detect, based on magnetic field data from a magnetic field sensor device coupled to the processor of the mobile device, in conjunction with map feature data of the indoor facility, existence of a distortive magnetic field; and
using the processor, localize the mobile device based on a subset of the set of data fusion inputs.
12 . The mobile device of claim 1 wherein the set of data fusion inputs includes wireless signal data, inertial sensor data, and the magnetic field data of the magnetic field sensor.
13 . The mobile device of claim 12 wherein the set of data fusion inputs further includes at least one of barometric data and optical line of sight data.
14 . The mobile device of claim 12 wherein the subset of the set of data fusion inputs excludes the magnetic field data.
15 . The mobile device of claim 12 wherein the magnetic field data includes at least one of a magnetic field strength, an orientation and a magnetic dip angle.
16 . The mobile device of claim 12 wherein the magnetic sensor device comprises a magnetometer of the mobile device.
17 . The mobile device of claim 16 further comprising instructions executable in the processor to deactivate the magnetometer during the existence of the distortive magnetic field;
18 . The mobile device of claim 12 wherein the map feature data is accessed from a localization fingerprint database for the indoor facility.
19 . The mobile device of claim 11 further comprising detecting a transition out of the distortive magnetic field based on the map feature data.
20 . The mobile device of claim 19 further comprising instructions executable in the processor that revert to localizing the mobile device based on the set of data fusion inputs.