Application of wavelet threshold method to DTG signal processing

In the process of azimuth measuring, the output signal of a gyro always contains noises caused by gyro drifting and ambient environmental influence. In order to reduce the noises and recover the original signal, conventional digital filtering methods such as IIR and FIR could be used. But the outputs of these filters would be distorted or in lack of smoothness under some special conditions. Wavelet analysis is suitable to this circumstance for its characteristic of multi-resolution of time and frequency and localization in space. Therefore, a wavelet threshold filter is designed, and the simulating result is given. A comparison was made on the results of wavelet threshold, IIR and FIR filtering method. The analysis demonstrates that wavelet threshold filtering performance is the best.