Initial Alignment of Strapdown Inertial Navigation System with the Aid of Doppler Velocity Log

This paper proposes an initial alignment approach for strapdown inertial navigation system with external information from Doppler velocity logs, aimed at improving navigated accuracy. Based on Kalman filtering theory, we make an analysis comparison between two different error models according to simulation results. Then, we respectively discuss the effects that measured velocity errors, height channel and different models do to the initial alignment accuracy of strapdown inertial navigation system. The experimental results show that the proposed approach can not only apply to initial alignment of height channel within short time, but also determine the velocity and position with satisfied precision.