Relative navigation of missile formation and INS error correction methods

Relative navigation of the missile formation is one of the key technologies for missile autonomous formation flight and cooperative detection. A relative navigation algorithm and an inertial navigation system (INS) error correction method based on mutual ranging and relative motion were proposed, using real-time ranging and data communication supported by the missile-borne data link in the global navigation satellite system (GNSS) free environment. Firstly, the measurement polygon with rotational ambiguity was obtained by the metric multidimensional scaling (MDS) method based on mutual ranging. Then the ambiguity was determined by the nodes' relative motions. Finally, the polygon translation method was applied to estimate INS errors according to the rank-defect network adjustment theory. Simulation results show that the proposed methods solve the rotational ambiguity problem for range-only relative navigation without inter-node angle measurements, as well as slow down the divergence trends of the INS position errors. For the formation of five missiles, the relative navigation accuracy is less than 30m when the ranging error is 20m and the INS accuracy is about three times of the original value.