用于改善捷联寻北仪抗动态干扰能力的小波消噪法

文章基于小波变换的消噪原理，结合待测信号的特点，创造性地提出一种适用于捷联寻北仪的小波消噪法。由于陀螺和加速度计输出的有用信号为平稳信号，不存在能被小波检测出的奇异性，因此对李氏指数大干零的干扰，用模极大值进行检测，并把模极大值用其左右相邻的几个非模极大值的平均值替代，滤去干扰：对李氏指数小于零的干扰采用软阈值法滤噪。该方法可显著提高捷联寻北仪抗动态干扰的能力。

Wavelet Denoising Method Using in Strapdown North Seeking System to Improve the Dynamic Disturbance

Base on wavelet denoising theory as well as the characteristic of the signal, a wavelet denoising method applied to Strapdown north seeking system was proposed. Because the signal of gyro and accelerometer is steady, there is no singularity to be examined by the wavelet. So this method uses mean value of non-maximum modules adjacent to the selected maximum module to alternate the maximum value, which is different from the old local maximum module reconstruction method. Disturbance whose Lipschitz exponent is bigger than zero is filterd. Soft-thresholding is used to filter noise whose Lipschitz exponent is smaller than zero. The method can improve the dynamic disturbance remarkably.