Cyclic Wiener Filtering Algorithm in Discrete Cosine Transform Domain for Vibration Signal

Abstract

In order to solve the problem that the effect of using cyclic Wiener filter directly to remove the noise on the non-stationary vibration signal is poor, the paper applies discrete cosine transform to the cyclic Wiener filter, proposing the cyclic Wiener filtering algorithm in discrete cosine transform domain for the vibration signal. Using the energy concentration characteristic of discrete cosine transform and the linear phase characteristic of cyclic Wiener filtering, the paper adopts the method of combining both of them with segmented processing to give full play to the performance of the Wiener filter and achieves a better filtering effect with a lower filter order. Combining with industrial field turbine vibration signal, paper makes a simulation analysis for this algorithm. The result of simulation shows that the algorithm has a good noise filtering effect, and the filtered signal has no obvious phase distortion. So, the algorithm is suitable for removing noise on vibration signal and the filtering effect is better than just using cyclic Wiener filter or DCT filter only.