The biological signal may be contaminated with noise from a variety of sources. Powerline noise has a significant effect on the signal, which occurs at 50 Hz frequency and reduces the SNR. As a result, the quality of the received signal decreases, and the extracted features cannot be reliable. Therefore, it is necessary to filter the available noise as much as possible to achieve the maximum SNR.

This is an Elliptical Notch filter for power line 50 Hz noise cancellation.