Hello ,i am trying to show frequency domain transform of 3 sinuos signal.I samples it twice the frequency of the highest frequency in the signal.
Althogh i get 3 harmonics but i dont get them at the 10,30,70 Hz and their amplitude is not 10(As shown in the code bello)
Where did i go wrong?
Thanks.
t=0:0.001:1f1=10;f2=30;f3=70;y1=10*sin(2*pi*f1*t);y2=10*sin(2*pi*f2*t);y3=10*sin(2*pi*f3*t);y4=y1+y2+y3;% twice the sampling rate
Fs=2*70;Ts=1/Fs;Tn=0:Ts:1;fft_L=length(Tn);y4_samples=10*sin(2*pi*f1*Tn)+10*sin(2*pi*f2*Tn)+10*sin(2*pi*f3*Tn);%stem(Tn_new,y4_samples);
ff=fft(y4,fft_L);plot(abs(ff));
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