How to create a filter in the time domain.

I have accelerometer data that I would like to filter but have to create the filter in the time domain. Does this mean I have to create a low pass filter using convolution or am I open to using the Matlab functions such as butter to create a low pas filter?

Answer 1

[Star Strider]

First, do an fft on your data so you can distinguish the frequency bands that have a valid signal from the low- and high-frequency noise. (That is explained in the fft documentation.) I would use a bandpass filter design to eliminate the d-c offset and baseline drift as well as high-frequency noise. A concise description of digital filter design is here. You may have to experiment a bit to get your filter to work as you want it to.