How to set minimum frequency to be analyzed with wavelet transform of ECG signal???

I am creating a gui that is meant to help with ecg signal analysis using wavelet transform. Currently there is no problem analyzing the signals and the program runs smoothly. However, I would like to add in a way to cut out data with a frequency lower than .05 HZ. In otherwards, I only want the data passed through the transform if it is between .05Hz and 100 Hz.

Currently, I'm using wavdec() to perform the transfoms with multiple wavelets and at different levels. Would I have to create a separate filter to pass the data through first? If so how would I go about doing that?

Answer 1

[Star Strider]

I’m not sufficiently skilled in wavelet filters to suggest a way to use them for your application. I would simply go with a digital bandpass filter (Chebychev may be best for your application, Butterworth is also an option). The second-order-section implementation is relatively easy to implement with the Signal Processing Toolbox.

I looked online to see what approaches are in the available (free) literature, and the digital filter seems to be the standard, so I feel safe in suggesting it. (See for example ‘Heartbeat Electrocardiogram (ECG) Signal Feature Extraction Using Discrete Wavelet Transforms (DWT)’, ‘Analysis of Butterworth and Chebyshev Filters for ECG Denoising Using Wavelets’, ‘FILTERING TECHNIQUES FOR ECG SIGNAL PROCESSING’.)

In the interests of time, I didn’t search the NCBI but I recommend it to you. It — particularly PubMed — likely has significantly more information.

[Connor]

Thanks so much!

[Star Strider]

My pleasure!