Aiming at problem of modulation result of gyro drift affects the navigation characteristics of rotation inertial navigation system(SINS).Gyro drift modulation characteristic caused by rotation device of double-axis rotation SINS is deduced.By means of Fourier transform
the crucial component of gyro drift after modulation is extracted.By inertial navigation error expression
navigation error characteristic of conditions with various rotation and stop time is solved and analyzed
and the optimized rotation scheme is confirmed.Computer comparison simulation result shows that the optimized scheme can enhance the position characteristics effectively.