How can I low-pass filter a high sample rate signal and output the signal at a lower rate in real time?

Hi,

I'm attempting some real-time Simulink for the first time and need a bit of advice.

I would like to clean up a noisy signal I am sampling so as to use it to generate an output signal.

Can anyone suggest how I can filter my high resolution input signal and then output a lower rate output signal with phase delay minimised?

Many thanks,

David

Answer 1

[Sandip Kumar]

Ideally you want to create a low-pass filter with phase delay minimization, and then downsample the signal.

For "low-pass filter with phase delay minimization":

• MATLAB: In MATLAB there is 'filtfilt' which does zero phase delay and can design a low-pass filter.
• Simulink: In Simulink, when working with blocks, you will have to use 'fdatool' to design a low-pass filter and tune the optimization options to have minimum phase delay

For 'downsampling' of signal:

• MATLAB: There is 'downsample' function
• Simulink: There is 'downsample' block

Thanks, Sandip