I want to compare two signals registered starting at the same time. The sampling frequency is 1 Hz for one signal and 200 Hz for the other one. It would be acceptable to average the signal at higher frequency to 1 Hz, so that a 1-to-1 link between signals over time may be established. To do so, I designed the following formula in Excel: =IF(MOD(B201;200)=0;AVERAGE(C2:C201);""), where B column contains a progressive count starting from 1 and and C the signal value. Unfortunately, the values sampled ad 200 Hz exceed Excel maximal row numbers. Is it possible to do the same using different programmes, such as MATLAB? Thank you in advance!
Hi, here is a link to a function that resamples your signal with minimal loss. For example, high frequency components are not smoothed away. Maybe this is useful for you.
https://de.mathworks.com/matlabcentral/fileexchange/35194-table-breakpoint-optimization
If your 200 Hz Signal is not too noisy you can simply pick every 200th value with the downsample function:
https://de.mathworks.com/help/signal/ref/downsample.html
If you want to follow the averaging approach you used in Excel, you may use a for-loop:
clear
data_1 = [0:1:1000]'; % generate 1 Hz Signal
data_200 = [0:0.005:1000]'; % generate 200 Hz Signal
j = 1;
for i = 1:length(data_200)
if mod(i, 200)==0
data_down(j,1) = mean(data_200(i-199:i,1)); % generate new Signal
j = j+1;
end
end
- Badges
- Science topic
- Similar topics
- Analytical Chemistry
- Column