频域除噪是信号降噪技术中的重要内容。由于噪声多为高频,频域除噪技术一般利用低通滤波器滤除含噪信号中的高频部分,以达到除噪的目的。然而图像信号的轮廓以及某些细节部分也为高频,会被低通滤波器当作噪声滤除,降低除噪效果。利用分数阶微积分,对滤波器算法进行细微变换和调整,使其能够更加精确地区分噪声与高频信号,从而在滤除噪声的同时更多地保留高频信号部分。文中通过大量的仿真,证明了该方法较传统的滤波除噪技术具有很大的进步性。

The denoising of frequency domain is an important content of signal denoising technology. For the frequency of noise is often high, low-pass filter is often used to filter out the high frequency part of noisy signal in the denoising of frequency domain, so the noise cancellation purpose is achieved. But the frequency of the outline and some details of image signal is high, they can be considered as noise and filtered out by low-pass filter, so the effect of denoising is reduced. Fractional calculus is used to transform and adjust the algorithm of filter slightly, so high frequent signal and noise will be divided more accurately. then more high frequent signal will be reserved while denoising. After lots of simulating, we proved that this method is more advanced than traditional filter denoising technology.

TN972+. 4