| 摘要 |
A navigation device (1) comprises: - a navigation state estimation unit (11) for repeatedly providing a navigation state estimate comprising at least one of the position, the velocity and the attitude of the device, - a prediction unit (12) for providing, using the navigation state estimate, a predicted magnetic property value, - a storage unit (13) for retrieving, using the navigation state estimate, a previously stored magnetic property value, - a subtraction unit (14) for producing the difference of the predicted magnetic property value and the retrieved magnetic property value, - a filter unit (15) for producing, using said difference, a navigation state correction value, and - a correction unit (16) for correcting, using said navigation state correction value, a corrected navigation state estimate. The prediction unit (12) comprises: - a magnetic measuring unit for repeatedly providing a measured magnetic field strength value, and - an integrating unit for integrating the measured magnetic field strength values to produce the magnetic property value corresponding with the navigation state estimate. |
