激光与光电子学进展, 2020, 57 (21): 210401, 网络出版: 2020-11-11
改进自适应小波降噪在激光陀螺仪信号处理中的应用 下载: 996次
Application of Improved Adaptive Wavelet Noise Reduction in Laser Gyroscope Signal Processing
探测器 激光陀螺仪 小波阈值降噪 最优阈值 最优分解层数 Allan方差 detectors laser gyroscope wavelet threshold noise reduction optimal threshold optimal number of decomposition layers Allan variance
摘要
针对传统小波函数处理激光陀螺仪输出信号存在的问题,提出一种含参数的阈值函数、自适应确定最优的分解层数和最优阈值相结合的小波阈值降噪方法。首先提出新的自适应阈值函数,然后基于最大能量熵原则计算小波比例能量熵以自适应确定小波最优的分解层数,并使用SURE(Stein Unbiased Risk Estimator)无偏估计原则与牛顿迭代法的结合方法自适应确定信号随时间变化的最优阈值,最后利用实测数据和Allan方差分析进行实验验证。实验结果表明,无论是静态激光陀螺仪信号还是动态激光捷联惯组信号,改进的自适应小波降噪方法的降噪效果优于传统的小波降噪方法以及标准卡尔曼滤波方法,且该方法处理后的信号精度更高、均方误差更小和噪声系数更小,有效抑制噪声对激光陀螺仪输出信号的干扰。
Abstract
Aiming at the problem of traditional wavelet function in processing laser gyroscope output signal, a new wavelet threshold denoising method with parameter threshold function, adaptive determination of optimal decomposition layer number and optimal threshold is proposed. First, a new adaptive thresholding function is proposed. Then, the wavelet proportional energy entropy is calculated based on the principle of maximum energy entropy, and the optimal number of decomposition levels of the wavelet is adaptively determined, and the combination method of SURE (Stein Unbiased Risk Estimator) unbiased estimation principle and Newton iteration method is used to determine the optimal threshold of signal change with time adaptively. Finally, the experimental verification is carried out by using the measured data and Allan variance analysis. Experimental results show that both static laser gyroscope signal and dynamic laser strapdown imu signal, the improved adaptive wavelet noise reduction method of the noise reduction result is better than that of the traditional wavelet thresholding method and the standard Kalman filtering method, and the method processed signal higher precision, smaller mean square error and smaller noise coefficient, which effectively restrain the interference of noise of laser gyroscope output signal.
李想, 汪立新, 段志强. 改进自适应小波降噪在激光陀螺仪信号处理中的应用[J]. 激光与光电子学进展, 2020, 57(21): 210401. Li Xiang, Wang Lixin, Duan Zhiqiang. Application of Improved Adaptive Wavelet Noise Reduction in Laser Gyroscope Signal Processing[J]. Laser & Optoelectronics Progress, 2020, 57(21): 210401.