In order to improve the rapid response ability of the inertial navigation system mounted on the aircrafts which are onboard a ship, a novel rapid transfer alignment method of the strapdown inertial navigation system (SINS) on a rocking base is put forward.Interfering motions such as rolling, pitching, and yawing motions caused by sea waves are effectively used. Meanwhile, to remedy the effects of modeling uncertainty and adapt the nonlinear character in the error models, a robust SDRE (state-dependent Riccati equation) filter design is developed based on the infinity-norm minimization criterion. The filter presented can solve the problem that the standard Kalman filter cannot give the optimal solution when the system model and stochastic information are unknown accurately. Simulation results show that the misalignment angle error estimation can be upgraded dramatically and the new algorithm is less sensitive to uncertainty noise.

Certain type of microwave range finder has been designed by adopting the technologies of DDS (direct digital frequently synthesis) digital signal synthesis and online signal detection, synthetically applying equal-accuracy frequency measuring method, automatic control of frequncy drift and quick interpolation method, combining WINDOWS API programming, Labview programing and fault disgnosis expert system. Eventually, accuracy verification and fault defect of microwave range finder are accomplished.