Use of spectral methods in strapdown ISS data processing

Characteristic frequencies and frequency bands are identified in the output of the inertial sensor block in a Ring Laser Gyro Strapdown Survey System by using Fast Fourier Transformation and are related to physical causes such as vehicle motion, environmental noise and sensor errors. A significant disturbance in the gyro and accelerometer outputs caused by the dither mechanism of the laser gyro is discussed. A frequency filtering approache to decrease the disturbing frequencies are studied. The effect of the filtering on the system performance is presented for field test results.