作者：王辛望1, 沈小林1, 刘新生2
作者单位：1. 中北大学计算机与控制工程学院, 山西 太原 030051;
2. 江苏曙光光电有限公司, 江苏 扬州 225009
关键词：随机误差;MEMS陀螺;阈值函数;小波阈值去噪;Allan方差;信噪比
摘要：
由于传统小波阈值去噪法在减小MEMS陀螺随机误差有很大的局限性，介绍一种改进阈值函数去噪法，通过调整阈值函数，克服传统方法的缺点和不足，从而减小MEMS陀螺随机误差，提高MEMS陀螺的精度。首先介绍传统阈值函数去噪法，然后基于传统阈值函数进行改进，提出一种新的阈值函数。采用改进后的方法对MEMS陀螺输出数据进行处理，并用Allan分析法比较传统方法与改进方法的效果。实验结果表明，角度随机游走（N）减少78.85%，零偏不稳定性（B）减小82.14%，角速率随机游走（R）减少92.53%，均值下降90.6%，均方差下降70%，信噪比增加26.43%，提高MEMS陀螺的精度。
Application of improved wavelet thresholding method for analysising MEMS gyroscope random error
WANG Xinwang1, SHEN Xiaolin1, LIU Xinsheng2
1. School of Computer and Control Engineering, North University of China, Taiyuan 030051, China;
2. Jiangsu Shuguang opto-electronics Co., Ltd., Yangzhou 225009, China
Abstract: Because the traditional wavelet threshold de-noising method has limitations in reducing the random error of MEMS gyroscope, this paper introduces an improved threshold function de-noising method, by adjusting the threshold function, to overcome the shortcomings of traditional methods, so as to reduce the random error and to improve the accuracy of MEMS gyroscope. The traditional threshold function de-noising methods have been introduced first, and then the methods have been improved, a new threshold function has been proposed. The new method and Allan analysis are used to analyze the random error of MEMS gyroscope and compare to the effect of these methods. Experimental results indicate that the angular random walk is reduced by 78.85%, the bias instability is reduced by 82.14%, the rate random walk is reduced by 92.53%, the average is declined 90.6%, average variance is decreased by 70%, the SNR is increased by 26.43% and the accuracy of MEMS gyroscope is improved.
Keywords: random error;MEMS gyroscope;threshold function;wavelet threshold de-noising;Allan variance;signal-noise ratio
2017, 43(11): 26-30 收稿日期: 2017-03-09;收到修改稿日期: 2017-05-04
基金项目:
作者简介: 王辛望(1991-),男,河北石家庄市人,硕士研究生,专业方向为控制理论与控制工程,导航、制导与控制。
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