针对地下磁性掩埋物检测时,磁异常信号信噪比低的问题,提出基于小波熵的微弱磁异常信号降噪方法.小波变换对弱磁异常信号进行提取的关键在于确定小波系数的阈值.为此,引入反映信号能量分布特性的小波熵概念和一个调节因子,最终确定阈值,利用软阈值方法处理高频系数.通过计算机仿真对算法进行了检验.结果表明:该算法可以有效地提高信噪比,还原原始信号.%A denoising method based on wavelet entropy is presented to solve the problem of low SNR in detecting magnetic anomaly signal of the hidden ferromagnetic objects.The key in extracting weak magnetic anomaly signal with wavelet transform is to determine the threshold of wavelet coefficients.Therefore,the concept of wavelet entropy and a coefficient that reflects the characteristic of signal energy distribution is introduced to determine the threshold,afterwards,the soft-threshold method is used to estimate the threshold of high-frequency coefficients.The proposed method is verified by simulation on computer.The results show that this method is effective to improve the SNR and recover the original signal.
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