A digital compass with two or more multi-axis magnetometers and a processing element to determine a heading and detect any offset error in the heading is described. One electronic device includes first and second magnetometers. The second magnetometer can be disposed at least a specified distance or co-located and offset at least a specified angle from the first magnetometer. A processing device determines a magnetic field at the electronic device using a first output from the first magnetometer, detects an offset error in the magnetic field using a second output from the second magnetometer, and reports the offset error in the magnetic field.

A digital compass with two or more multi-axis magnetometers and a processing element to determine a heading and detect any offset error in the heading is described. One electronic device includes first and second magnetometers. The second magnetometer can be disposed at least a specified distance or co-located and offset at least a specified angle from the first magnetometer. A processing device determines a magnetic field at the electronic device using a first output from the first magnetometer, detects an offset error in the magnetic field using a second output from the second magnetometer, and reports the offset error in the magnetic field.

An electronic device may include a magnetic sensor and at least one processor operatively connected with the magnetic sensor, wherein the at least one processor may be configured to: collect a plurality of pieces of path data based on first magnetic data related to a plurality of movements of the electronic device, by using the magnetic sensor; identify a plurality of pieces of second magnetic data, which have at least a predetermined level of mutual similarity, from among the plurality of pieces of path data; determine, to be an intersection area related to the plurality of movements of the electronic device, an area range in which the plurality of pieces of second magnetic data are collected; determine, on the basis of the intersection area, a first space and a second space related to the plurality of movements of the electronic device; and determine, on the basis of the third magnetic data acquired by using the magnetic sensor, the space in which the electronic device is located from among the first space and the second space.

Systems and methods are presented for establishing a communication link between two or more electronic devices. A portable eyewear electronic device is configured to communicate with a handheld electronic device, such as a ring, that in turn is retained by an accessory electronic device to establish a wired communication link. The accessory electronic device may be retained or housed by a second accessory electronic device, such as a remote control or wearable device.

Systems and methods are presented for establishing a communication link between two or more electronic devices. A portable eyewear electronic device is configured to communicate with a handheld electronic device, such as a ring, that in turn is retained by an accessory electronic device to establish a wired communication link. The accessory electronic device may be retained or housed by a second accessory electronic device, such as a remote control or wearable device.

Magnetic field measurement by a set of magnetometers which are linked to a same moveable support and which have different orientations of eigendirections with respect to this support A processor determines, during a measurement in a given position and orientation of the support and of the set of magnetometers, for each magnetometer, of the orientation deviation between the eigendirections of the magnetometer and a candidate magnetic field, the magnetometer for which this deviation is minimal, the magnetic field measured by this sensor being selected as the magnetic field measured by the set of magnetometers. The magnetometers are distributed in space in order to cover a maximum of different orientations.

Magnetic field measurement by a set of magnetometers which are linked to a same moveable support and which have different orientations of eigendirections with respect to this support A processor determines, during a measurement in a given position and orientation of the support and of the set of magnetometers, for each magnetometer, of the orientation deviation between the eigendirections of the magnetometer and a candidate magnetic field, the magnetometer for which this deviation is minimal, the magnetic field measured by this sensor being selected as the magnetic field measured by the set of magnetometers. The magnetometers are distributed in space in order to cover a maximum of different orientations.

In one implementation, a method of estimating the heading of a device is performed by the device including a processor, non-transitory memory, and an image sensor. The method includes determining a geographic location of the device. The method includes capturing, using the image sensor, an image at the geographic location. The method includes detecting one or more lines within the image. The method includes determining a heading of the device based on the one or more lines and the geographic location.

Systems and methods for determining azimuth of a wellbore while drilling. A method of drilling a wellbore that includes rotating a drill bit to extend the wellbore into a subterranean formation. The method may further include measuring magnetic toolface with a first magnetometer while rotating the drill bit. The method may further include obtaining a cross-axial magnetic field measurement. The method may further include determining azimuth at a point in the wellbore using at least the magnetic toolface and the cross-axial magnetic field measurement. The method may further include using the azimuth as feedback in the drilling the wellbore.

In one embodiment, a method includes accessing a magnetic map of an area that includes magnetic-field values for locations in the area. The method also includes accessing an image file that includes pixels that correspond to the locations and include components. The image file also includes a first matrix with elements that each include color values. The components of the pixels include links to elements in the first matrix. The method also includes embedding portions of the magnetic map into the image file by generating a second matrix for the image file including elements that represent the magnetic-field values and, for the locations in the area, writing to the components of the pixels corresponding to the locations links to elements of the second matrix. The method also includes communicating the image file, with the portions of the magnetic map embedded in it, to computing devices for navigation or localization.