Skip to main content
added 178 characters in body
Source Link
Andy aka
  • 503.2k
  • 35
  • 401
  • 886

I don't understand the question nor do I understand why the bode plot is marked with a pole and a zero and here's why: -

A typical pole zero diagram for a 2nd order low pass filter: -

enter image description here

The vertical axis is jw and this is also the base frequency axis of a bode plot like this one (also a 2nd order low pass filter): -

enter image description here

Behind the resonant peak in the bode plot above is lurking a pole but you cannot draw it on the bode plot because neither of the pole's co-ordinates are exactly along the frequency axis.

And together, in 3 dimensions they look like this: -

enter image description here

As you can see, you cannot mark a pole on a bode plot unless it occurs right on the jw axis but, then the bode plot peak would rise to infinity and it doesn't on your bode plot.

You also cannot mark a zero on a bode plot for the same reasonreasons namely the bode plot HAS to be zero if there is a zero with a co-ordinate along the jw axis. If it's not there then you can't mark it on the bode plot because it makes no sense.

Pictures from here.

I don't understand the question nor do I understand why the bode plot is marked with a pole and a zero and here's why: -

A typical pole zero diagram for a 2nd order low pass filter: -

enter image description here

The vertical axis is jw and this is also the base frequency axis of a bode plot like this one (also a 2nd order low pass filter): -

enter image description here

Behind the resonant peak in the bode plot above is lurking a pole but you cannot draw it on the bode plot because neither of the pole's co-ordinates are exactly along the frequency axis.

And together, in 3 dimensions they look like this: -

enter image description here

As you can see, you cannot mark a pole on a bode plot unless it occurs right on the jw axis but, then the bode plot peak would rise to infinity and it doesn't on your bode plot.

You also cannot mark a zero on a bode plot for the same reason.

Pictures from here.

I don't understand the question nor do I understand why the bode plot is marked with a pole and a zero and here's why: -

A typical pole zero diagram for a 2nd order low pass filter: -

enter image description here

The vertical axis is jw and this is also the base frequency axis of a bode plot like this one (also a 2nd order low pass filter): -

enter image description here

Behind the resonant peak in the bode plot above is lurking a pole but you cannot draw it on the bode plot because neither of the pole's co-ordinates are exactly along the frequency axis.

And together, in 3 dimensions they look like this: -

enter image description here

As you can see, you cannot mark a pole on a bode plot unless it occurs right on the jw axis but, then the bode plot peak would rise to infinity and it doesn't on your bode plot.

You also cannot mark a zero on a bode plot for the same reasons namely the bode plot HAS to be zero if there is a zero with a co-ordinate along the jw axis. If it's not there then you can't mark it on the bode plot because it makes no sense.

Pictures from here.

Source Link
Andy aka
  • 503.2k
  • 35
  • 401
  • 886

I don't understand the question nor do I understand why the bode plot is marked with a pole and a zero and here's why: -

A typical pole zero diagram for a 2nd order low pass filter: -

enter image description here

The vertical axis is jw and this is also the base frequency axis of a bode plot like this one (also a 2nd order low pass filter): -

enter image description here

Behind the resonant peak in the bode plot above is lurking a pole but you cannot draw it on the bode plot because neither of the pole's co-ordinates are exactly along the frequency axis.

And together, in 3 dimensions they look like this: -

enter image description here

As you can see, you cannot mark a pole on a bode plot unless it occurs right on the jw axis but, then the bode plot peak would rise to infinity and it doesn't on your bode plot.

You also cannot mark a zero on a bode plot for the same reason.

Pictures from here.