Method for designing digital filter applied in inertia device

The invention relates to a method for designing a digital filter applied in an inertia device. The method is characterized by comprising the following steps of: determining an amplitude attenuation allowable value according to the precision of the inertia device, determining a phase delay allowable value according to the performance index of a strap-down inertial navigation system, and determining certain technical parameters of the filter according to the actual signal power spectrum analysis of the inertia device; designing a reference analog filter, converting the reference analog filter into an infinite impulse response (IIR) digital filter by using a bilinear transform method, observing a bode diagram in the filter parameter adjusting process, and performing off-line simulation calculation according to the actually measured data; and performing judgment by using de-noising effect, common cutoff frequency, amplitude attenuation and phase delay as fuzzy variables and using fuzzy rules to optimize the integ