Digital Band pass filter on Arduino

Question

I am working with sensors on Arduino and would like to filter the sensor's output to a certain band of frequencies.

I found many examples online on how to implement simple digital low-pass filters in Arduino code, but not for band pass filters.

Is it even possible to achieve this in the scope of an Arduino program? If anyone can share some tutorial for this, that would be much appreciated.

• Majenko: On an Arduino I would be tempted to do it in hardware. You really need a DSP to do filtering like that.
• Mikael Patel: See iowahills.com/Example%20Code/WindowedFIRFilterWebCode.txt from iowahills.com/A7ExampleCodePage.html

Answer 1

A band pass filter simply means that it a filter between a certain interval of frequencies thus it can be made from a high pass filter and a low pass filter

e.g. this fact is mentioned here http://www.electronics-tutorials.ws/filter/filter_4.html

as well as lots of other web pages which a search by you can find. So yes a band pass filter can be implemented on arduino if you can implement the corresponding high pass and low pass filter too.

• TanyaV: The link you posted leads to analog filters where i specifically asked about ones implemented within the Arduino code, im afraid it is not relevant. if i were to somehow implement both a low pass and a high pass filter separately in an arduino program, ill just lose both my high and low frequencies as they will both get filtered out.
• Pete: Its easy enough to find the defintion of a band pass filter by a simple search which you can do
• Pete: for a more relevant link
• Pete: Sounds like you need to use two arduino (or at least two different signal filter circuits) to make a band pass filter
• Pete: you implmented a low pass filter, you merely have to implment a high pass filter then combine the two to get a band pass filter.