Plot the amplitude and phase response for the given FIR system.

1-2z^-1+4z^-2

Plot the amplitude and phase response for the given FIR system.

[Walter Roberson]

How does this differ from https://www.mathworks.com/matlabcentral/answers/1909670-plot-fir-system-magnitude-and-phase?s_tid=srchtitle ?

Answer 1

[Sarvesh Kale]

Hi Abod,

To plot the frequency response of FIR system use the following code

b=[1 -2 4]; % define numerator coefficient 
a=[1];      % define denominator coefficient  
figure ;
freqz(b,a,2048) % plot frequency response for 2048 points 

You can take a look at following documentation of freqz and phasez to get more information on them

https://in.mathworks.com/help/signal/ref/freqz.html and

https://in.mathworks.com/help/signal/ref/phasez.html

I hope this answers your queries, please accept the answer if it does.

Thank you.

Answer 2

[Sulaymon Eshkabilov]

Use tf() and bode():

z = tf('z',0.1);
H = (4*(z^-2)-2*(z^-1)+1) /1

H =
 
  z^3 - 2 z^2 + 4 z
  -----------------
         z^3
 
Sample time: 0.1 seconds
Discrete-time transfer function.

bode(H)