A new adaptive Kalman filter for navigation systems of carrier-based aircraft

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The features of carrier-based aircraft\'s navigation systems during the approach and land-ing phases are investigated.A new adaptive Kalman filter with unknown state noise statistics is pro-posed to improve the accuracy of the INS/GNSS integrated navigation system.The adaptive filtering algorithm aims to estimate and adapt the unknown state noise covariance Q in high dynamic conditions,when the measurement noise covariance R is assumed to be known empirically in advance.The new adaptive Kalman filter based on the innovation sequence and pseudo-measurement vector approach makes it more effective to estimate and adapt Q.The simulation results and semi-physical experiments show that the application of the proposed adaptive Kalman filter can guarantee a higher estimation accuracy of the state variables.
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