补偿圆滑滤波方法

FILTERING OF SMOOTH COMPENSATION

在实际工作中,总希望有这样一种压制高频干扰的理想滤波器:它能把大于某一指定频率的成份“绝对”地压制掉,又“绝对”地使小于这一指定频率的成份不发生畸变.但是,在数字滤波中,到目前为止还未见到有一种充分光滑的函数可以作为这种滤波器,补偿圆滑滤波方法就是为了解决这个问题而提出来的.在频率域中,对于压制信号中的高频成份来说,现有的充分光滑的函数,虽然能起很大的压制作用,但同时也会在一定程度上压制中频和低频成份,这种对中频和低频成份的压制,却是我们所不希望发生的.为了减少这种对中、低频成份的压制,我们提出了一种新的滤波方法,这就是本文所要介绍的补偿圆滑滤波法.

Practically, it is always hoped that such an ideal HF noise suppression filter could be acquired: which can absolutely suppress all the frequencies higher than a given value, and at the same time, it wouldn't bring any distortions to those which are lower than that of the given value. However, even up to now, we have never seen such a function which is smooth enough and can be used as this kind of filtering mentioned above. The smooth compensation filtering presented here is just for the purpose of solving this problem.As is well known, in frequency domain, though the fully smooth functions now available could suppress the HF frequencies ever so much, it suppresses, to some extent, the MF and the LF frequencies simultaneously. That shouldn't really be expected anyway.In order to decrease such kind of suppressions to minimum, a newfiltering method has thus been worked out at last--this is the so called"Smooth Compensation Filtering" described in this paper.