Bode plot normalization process

• jeffy
In summary, the person is trying to normalize a 8th order s-domain transfer function for plotting a bode plot. They want to normalize the frequency by dividing it by a frequency f0 instead of just using j2πf. They are unsure if they should divide all the terms by (1/ω0)^8 or extract the 1/w0 factor out of the coefficients. They also question if normalizing the plot will still result in j(w/w0) being equal to s.

jeffy

Hi,

I have a 8th order s-domain transfer function that i would like to normalize for plotting a bode plot. The transfer function is in expanded form i.e. s^8 +s^7+s^6 etc.

i want to normalise the frequency f by frequency f0 such that s = j(f/f0) instead of just s = j2πf. the reason i want to do this is because i see some strange behaviour (asymptotes) if i plot the non-normalised version, so I am hoping this will solve the problem.

the thing I am unsure of is that, since my highest degree is 8 (in the denominator), is it as simple as dividing all the terms by (1/ω0)^8? is there some other methods that i can use since the transfer function is not one that is really simple to work with. (coefficients in the range of 1e-30)

OR

would i be extracting the 1/w0 factor out of my coefficients? i.e. if the term is 5s^2, would the normalised version be 5/(w0^2) s^2? (this compared to the above where i would have 5/(w0^8)s^2.

i suppose I am also curious if we normalise the plot, does j(w/w0) still equal to s? why does this still work?

thanks all

What you asked is equivalent to choosing a different unit of time. Instead of f being cycles per second, it is cycles per bazfaz. That changes nothing.

What is a Bode plot normalization process?

The Bode plot normalization process is a technique used in signal processing to convert the frequency response of a system into a standard form. This allows for easier comparison and analysis of different systems.

Why is Bode plot normalization necessary?

Bode plot normalization is necessary because it helps to remove the effects of the system's gain and time constant, allowing for a clearer representation of the system's frequency response. It also allows for easier comparison between different systems.

How is Bode plot normalization performed?

Bode plot normalization is typically performed by dividing the frequency response by the system's gain and time constant. This results in a standardized plot with a magnitude of 1 at the system's corner frequency.

What are the benefits of using Bode plot normalization?

Bode plot normalization has several benefits, including allowing for easier comparison and analysis of different systems, removing the effects of gain and time constant, and providing a standardized form of the frequency response for better understanding and interpretation.

Are there any limitations to the Bode plot normalization process?

While Bode plot normalization can be a useful tool, it does have limitations. For example, it may not be appropriate for systems with complex dynamics or nonlinearities. Additionally, the normalization process may introduce errors in the frequency response, so it should be used with caution and in conjunction with other methods for system analysis.