System level compensating method of platform type inertial navigation system

The invention provides a system level compensating method of a platform type inertial navigation system, for solving the problem that the inertial navigation system has slowly accumulated errors in a use process. According to the system level compensating method disclosed by the invention, a navigation gyroscope is changed to be a dual-shaft gyroscope on the basis of the condition that two conventional ship long endurance inertial navigation systems are used to work individually and are backed up mutually, so that data processing is carried out by using output information to modify shift of the gyroscope. With the adoption of the system level compensating method disclosed by the invention, the volume and the weight of the platform type inertial navigation system can be effectively reduced. Meanwhile, the slowly accumulated errors of the inertial navigation system in the use process are removed, so that the reliability of the system is improved.