Design of master-slave filter and its application to transfer alignment

A master-slave adaptive filter is designed and its application to shipboard transfer alignment is studied. Although the velocity and angular rate matching scheme offers a rapid transfer-alignment for shipboard inertial navigation systems, it is sensitive to ship flexure. The flexure is modeled as a time-varying noise, of which the stochastic properties are estimated by an adaptive filter. Two Kalman filters are designed, one is the master filter for estimating the dynamic states, the other is for estimating the measurement noise statistics based on the master filter residuals. These two filters exchange information and run simultaneously. Simulation results show that the misalignment angles of slave navigation system can be estimated rapidly and accurately by the proposed filter.