# High pass filter not attenuating signal at start of input

I have implemented digital high pass filter with below specs:

Sampling frequency = 5333 Hz
Cutoff frequency = 10 Hz
Order = 3


We are facing problem like below:

As per result shown above signal gets attenuation after $$1000$$ data points. How can solve this kind of issue?

Any help/ suggestion would be great and appreciable! Thanks in advance.

• Please show us the unfiltered data and then the filtered data.
– Ben
Nov 2, 2020 at 14:20
• Also, what is the filter transfer function ?
– Ben
Nov 2, 2020 at 14:21
• If the filter you are using has a long impulse response, it will take a large number of samples to essentially fill/enter the filter before it becomes effective. Additionally, if the frequency content in the first 1000 samples is in the passband of the filter, then it wouldn't be much. Nov 2, 2020 at 14:30
• Nov 4, 2020 at 11:07
• Transfer Function: $$y = {(0.9883 s^3 - 2.965 s^2 + 2.965 s - 0.9883)} / {(s^3 - 2.976 s^2 + 2.953 s - 0.9767)}$$ Nov 4, 2020 at 11:12