Notch Filter to remove noise from an ECG Signal
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This experiment is based on a question at the Lab Exam (EN1093).
According to the following difference equation which relates output (y[n]) and input (x[n]) we were asked to derive the transfer function H(z). This filter removes the 50Hz noise component.
download the ECG Signal distorted with noise
Pole-zero Plot
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MATLAB code to implement the Notch Filter with the above characteristics
Implementation output ->
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For Further reading:
https://en.wikibooks.org/wiki/Control_Systems/Poles_and_Zeros
http://web.mit.edu/2.14/www/Handouts/PoleZero.pdf
https://dsp.stackexchange.com/questions/6103/adding-noise-to-an-ecg-signal