1、Mask the signal set with the unwanted signals.
2、the presence of an unwanted signal via an accidental coupling.
3、Electrical noise - essentially any unwanted signal - can arise from a number of sources.
4、Filter is a useful signal can pass while the frequency of the unwanted signal suppression (or attenuation) of the electronic devices.
5、The classification of the errors due to unwanted signals is described.
6、On a communications link, noise or unwanted signals that impair the receipt or correct interpretation of speech or data.
