In loose combined navigation system

using the SINS error as state quantity

the difference between the position and velocity of the SINS solution and the difference of position and velocity measured by GPS as measurement information. In order to improve the precision of integrated navigation

using the eatended Kalman filtering（ EKF） algorithm in loose combination of navigation

through simulation

trajectory speed

attitude

position tracking of the carrier are carried out. The simulation results show that the system enters the steady state after 8 minutes

and it can accurately track the carrier. Therefore

the nonlinear filtering based on EKF can effectively track the position

velocity and attitude of the carrier.