Design of horizontal damping network for INS based on complementary filtering

Schuler oscillation damping is one of the key technologies to improve the long-term precision of INS.It is difficult for inertial systems using low-order networks to perfectly perform restraining on both high-frequency and low-frequency reference velocity errors.In this paper,a high-order horizontal damping network based on complementary filtering was designed,in which the damped Schuler loop may obtain 40 dB/10 deg or higher attenuation to both high-frequency and low-frequency reference velocity errors.Such single loop is equivalent to two-loop of integrated system using low-order damping network which perform good in high frequency and low frequency respectively.Computer simulation and sea trial results show that inertial systems adopting the designed high-order network achieve excellent filtering characteristics in both high frequency and low frequency,which are better than those using low-order networks and have merits in engineering applications.