MATLAB: Transfer Function and Input Signal

transfer function time algebra relation filter filters input output matrix matrices signal frequency

I have have the following transfer function for a noise filter
R=220;
a=.95;
C=900.*10^-9;
num=[(R^2.*C^2) 0 1];
den=[(R^2.*C^2) (4.*R.*C.*(1-a)) 1];
H=tf(num/den);
bode(H)
This is also define as Vo/Vi and it filters input signals at a frequency of 5khz. i was given an Input Voltage on a data table and im trying to graph the Vo. Im using my relation H=(Vo/Vi) to graph Vo as Vo=H(Vi). Im doing this the following way
H=(num/den).*(ttsignal)
ttsignal is my input voltage btw…
after i do this and i graph my plot basically overlaps, my output signal perfectly matches my input signal.which basically means the filter is doing nothing… its getting and input and the output has no change whatsoever…
what im doing wrong in here…
ill appreaciate any help
thank

Best Answer

Use the lsim function with your time vector and matching ‘ttsignal’ input.