CAJ | 학술논문

各种随机噪声是导致激光陀螺产生误差的主要因素,且其性质特殊,很难用传统的滤波方法去除.为了抑制激光陀螺的随机漂移,提高使用精度,提出了一种新型经验模态分解方法对陀螺随机漂移测试信号进行滤波处理.该方法将经验模态分解的内模函数中两个相邻过零点之间的信号定义为模态单元,并作为基本分析对象,通过对模态单元振幅的阈值处理来判断模态单元的类型,进而建立模态单元滤波模型.分析了经验模态分解法在分解不同Hurst指数分形高斯噪声时模态振幅的演化规律,并建立了一种用于高斯消噪的阈值选取规则.运用该方法对激光陀螺测试数据进行了滤波降噪实验,并用Allan方差法对不同降噪算法的降噪效果进行了比较分析,实验结果验证了该方法的有效性和优越性.
각충수궤조성시도치격광타라산생오차적주요인소,차기성질특수,흔난용전통적려파방법거제.위료억제격광타라적수궤표이,제고사용정도,제출료일충신형경험모태분해방법대타라수궤표이측시신호진행려파처리.해방법장경험모태분해적내모함수중량개상린과영점지간적신호정의위모태단원,병작위기본분석대상,통과대모태단원진폭적역치처리래판단모태단원적류형,진이건립모태단원려파모형.분석료경험모태분해법재분해불동Hurst지수분형고사조성시모태진폭적연화규률,병건립료일충용우고사소조적역치선취규칙.운용해방법대격광타라측시수거진행료려파강조실험,병용Allan방차법대불동강조산법적강조효과진행료비교분석,실험결과험증료해방법적유효성화우월성.
The various random noises in laser gyro are the main factors generating errors. In accordance with the special property of laser gyro's noise, traditional filtering methods have many shortages to remove the noise. In order to restrain the random floating and improve the applicability precision for laser gyro, an improved de-noising algorithm based on the empirical mode decomposition (EMD) was proposed. The signal between the two adjacent zero crossing points within the intrinsic mode function (IMF) of EMD was defined as the modular cell by the method, which was treated as the basic analyzable object. Categories for the modular cell were judged by dealing with the amplitude of the cell, and then the filtering model was established. Evolutional rules of the amplitude for the modular cell were analyzed when the noisy signal corrupted by fractional Gaussian noise with different Hurst exponent were decomposed by EMD method, and threshold choosing rules used in Gaussian de-noising were also established. A signal de-noising test for laser gyro was performed to demonstrate the performance of the method. Compared with different de-nosing algorithms based on Allan variance method, the experimental results demonstrate the validity and superiority of the proposed algorithm.