基于VMD和CWT的MEMS陀螺仪输出降噪研究

Research on Noise Reduction of MEMS Gyroscope Output Based on VMD and CWT

针对MEMS陀螺仪信号噪声的问题,提出了一种基于变分模态分解(VMD)和连续小波变换(CWT)相结合的去噪方法。方法首先利用VMD算法将MEMS陀螺仪信号分解成若干不同频率的本征模态分量(IMF),有效的抑制了LMD分解中存在的模态混叠现象和端点效应等问题,经过信号重构之后,再用CWT算法进行二次去噪处理,分离出有效的低频信号。将上述方法应用到实际工程中,并与传统的VMD去噪和传统的CWT去噪方法作对比,实验结果表明VMD和CWT联合降噪方法可以有效地去除MEMS陀螺仪输出信号中的噪声,对改善MEMS陀螺仪零偏稳定性有着较好的作用,为工程中解决MEMS陀螺仪降噪问题提供了新思路。

Aiming at the problem of signal noise of MEMS gyroscope, this paper proposed a denoising method based on the combination of variational mode decomposition(VMD) and continuous wavelet transform(CWT). Firstly, the VMD algorithm was used to decompose the MEMS gyroscope signal into several eigenmode components(IMF) of different frequencies, which effectively suppressed the modal aliasing phenomenon and end effect in the LMD decomposition. After that, the CWT algorithm was used for secondary denoising to separate the effective low-frequency signals. The method was applied to the actual engineering and compared with the traditional VMD denoising and the traditional CWT denoising method. The experimental results show that the VMD and CWT joint noise reduction method can effectively remove the noise in the output signal of the MEMS gyroscope. It has a good effect on improving the zero-bias stability of MEMS gyroscopes and provides a new idea for solving the problem of noise reduction of MEMS gyroscopes in engineering.