Notch filter

Notch filter refers to a filter that can quickly attenuate the input signal at a certain frequency point to achieve a filtering effect that prevents the signal of this frequency from passing through. The notch filter is a type of band stop filter, but its stop band is very narrow, and the starting order must be second order (including second order) or above.


Some applications of notch filters include:

(1) Notch filters are commonly used in communication systems, instrumentation and control systems, and biomedical fields to eliminate 50/60Hz power line interference.

(2) Notch filters or band stop filters are widely used in electronic and communication circuits to suppress unwanted frequency bands and allow other frequencies to be transmitted with minimal loss.

(3) The switching types of AC and DC motor drives, converters and inverters can cause sinusoidal disturbances at certain harmonics of the line frequency. The use of a notch filter eliminates this unwanted interference and enables accurate measurements.

(4) It is used in telephone technology, DSL and other Internet services as a line noise reducer to reduce unwanted interference.

(5) Rejection of unwanted frequencies, i.e. noise, is highly preferred in image, audio and signal processing.

(6) It is used in medical field applications, i.e. ECG (electrocardiogram) measurements, to eliminate the DC component.

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Post time: May-23-2024