Bandwidth of transfer function

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Bandwidth of transfer function

Θύμιος Γρίβας
Hello there,
I want to calculate the bandwidth of a transfer function but i have a problem.
this is my code:
pkg load control
A=tf(20,[1 2 30]);
bandwidth(A)

Of course A is not a matrix and this is a problem.
How can i calculate the bandwidth? I can not find any solution in the internet.

Thank you in advance,
Grivas Efthimios


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Re: Bandwidth of transfer function

Doug Stewart-4


On Sun, Mar 25, 2018 at 11:54 AM, Θύμιος Γρίβας <[hidden email]> wrote:
Hello there,
I want to calculate the bandwidth of a transfer function but i have a problem.
this is my code:
pkg load control
A=tf(20,[1 2 30]);
bandwidth(A)

Of course A is not a matrix and this is a problem.
How can i calculate the bandwidth? I can not find any solution in the internet.

Thank you in advance,
Grivas Efthimios



The bandwidth that you are seeing is from the linear math matrix section.

For a control signal bandwidth: here is a quick rendition.
save this as lpbandwidth.m

 A=tf(20,[1 2 30]);
 bode(A)
 dcgain1=dcgain(A)
 [ mag,p,w]=bode(A);
 q=find(mag<dcgain1/2);
 index1=q(1);
 gain2=mag(index1)
 bw=w(index1)
 st1=mat2str(bw,6)
 disp(["the bandwidth of this lowpass filter is " st1 " radians per second"])


I will work on making a bandwidth function in the control tool box.



--
DAS



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Re: Bandwidth of transfer function

Θύμιος Γρίβας
Thanks for the quick response. 

Στις Κυρ, 25 Μαρ 2018, 20:53 ο χρήστης Doug Stewart <[hidden email]> έγραψε:


On Sun, Mar 25, 2018 at 11:54 AM, Θύμιος Γρίβας <[hidden email]> wrote:
Hello there,
I want to calculate the bandwidth of a transfer function but i have a problem.
this is my code:
pkg load control
A=tf(20,[1 2 30]);
bandwidth(A)

Of course A is not a matrix and this is a problem.
How can i calculate the bandwidth? I can not find any solution in the internet.

Thank you in advance,
Grivas Efthimios



The bandwidth that you are seeing is from the linear math matrix section.

For a control signal bandwidth: here is a quick rendition.
save this as lpbandwidth.m

 A=tf(20,[1 2 30]);
 bode(A)
 dcgain1=dcgain(A)
 [ mag,p,w]=bode(A);
 q=find(mag<dcgain1/2);
 index1=q(1);
 gain2=mag(index1)
 bw=w(index1)
 st1=mat2str(bw,6)
 disp(["the bandwidth of this lowpass filter is " st1 " radians per second"])


I will work on making a bandwidth function in the control tool box.



--
DAS