Signal Decomposition for a mixed signal
11 views (last 30 days)
Show older comments
Hi friends,
Suppose we have a mixed signal X composed of three component signals x1, x2, and x3:
t=0:0.00001:0.3;
x1=(exp(-3*t)).*(0.2*sin(2*pi*400*t));
x2=1.2+(exp(-1.5*t)).*(1.1*sin(2*pi*40*t+pi/6));
x3=(exp(-5*t)).*(0.8*sin(2*pi*75*t+pi/3));
X=x1+x2+x3;
subplot(4,1,1);
plot(t,x1);title('Component signal: x1');
subplot(4,1,2);
plot(t,x2);title('Component signal: x2');
subplot(4,1,3);
plot(t,x3);title('Component signal: x3');
subplot(4,1,4);
plot(t,X);title('Mixed signal: X=x1+x2+x3');
Now, inversely, how can we obtain the samples of the three component signals x1, x2, and x3 without any additional information except the samples of the mixed signal X?
I would be very grateful if anyone could provide a code or efficient technique for this challenging example.
Thanks in advance for your help.
Note: Unfortunately, the ICA package and also the function emd() did not lead to a desired result. Is there any other practical solution for this example?
5 Comments
Accepted Answer
Ridwan Alam
on 19 Dec 2019
t=0:0.00001:0.3;
x1=(exp(-3*t)).*(0.2*sin(2*pi*400*t));
x2=1.2+(exp(-1.5*t)).*(1.1*sin(2*pi*40*t+pi/6));
x3=(exp(-5*t)).*(0.8*sin(2*pi*75*t+pi/3));
X=x1+x2+x3;
fs = 1/.00001;
z1 = highpass(X,350,fs);
z3 = bandpass(X,[60 100],fs);
z2 = X - (z1 + z3);
Z = z1 + z2 + z3;
3 Comments
Ridwan Alam
on 23 Dec 2019
Edited: Ridwan Alam
on 23 Dec 2019
Indeed. This answer assumes the pass bands are known beforehand. Moreover, the exponentially decaying function is not really decomposed well, as their frequency bands are different than the sin components. It just answers toy examples for learning filters, do not use in real general purpose applications.
Srivatsa Dasa
on 2 Apr 2022
how to decompose a random .wav signal if its pass bands are unknown. Is it possible to decompose the signal
More Answers (0)
See Also
Categories
Find more on Transforms in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!