The Accuracy Of The Gps-Derived Acceleration Vector, A Novel Attitude Reference

The accuracy with which acceleration can be determined from GPS data has been investigated. This has been done to evaluate whether the GPS acceleration could provide a reasonably accurate attitude reference when compared to the acceleration measured by an accelerometer on board a vehicle. The accuracy of the GPS acceleration signal has been investigated in 2 ways. One way has been to use actual receiver data for receivers with known accelerations. The other way has been to mathematically determine the acceleration inaccuracy induced by Selective Availability and based on a model of this principal noise source. Experimental acceleration accuracy of 0.009 g was obtained at a I Hz sampling frequency. The predicted achievable accuracy is 0.04 g at a 20 Hz sampling frequency. In this latter situation the acceleration vector could provide an attitude reference that is accurate to about 20.