| 摘要 |
A portable navigation device comprises an accelerometer, a GPS receiver, and a calibration module The calibration module generates calibration parameters that enable acceleration data from the accelerometer to be accurately converted into speed and heading data and integrated over time to give distance data The calibration parameters are calculated from GPS derived speed and heading data and resolve or otherwise compensate for (i) the attitude of the portable device with respect to the horizontal plane ("pitch") and (ii) the angle between the forward direction of the device and the driving direction of a vehicle the device is mounted in ("yaw") |
