Frequency response of rational function object
[resp,outfreq] = freqresp(h,infreq)
[resp,outfreq] = freqresp(h,infreq) computes
the frequency response,
resp, of the rational function
h, at the frequencies specified by
h is the handle of a rational function
object returned by
a vector of positive frequencies, in Hz, over which the frequency
response is calculated.
The output argument
outfreq is a vector that
contains the same frequencies as the input frequency vector, in order
of increasing frequency. The frequency response,
is a vector of frequency response values corresponding to these frequencies.
It is computed using the analytical form of the rational function
Delay are properties of the rational function
Compute the frequency response of data stored in the file,|passive.s2p| by reading it into an
rfdata object, fitting a rational function object to the data, and using the
freqresp method to compute the frequency response of the object
orig_data=read(rfdata.data,'passive.s2p') freq=orig_data.Freq; data=orig_data.S_Parameters(2,1,:); fit_data=rationalfit(freq,data) [resp,freq]=freqresp(fit_data,freq); plot(freq/1e9,20*log10(abs(resp))); figure plot(freq/1e9,unwrap(angle(resp)));
orig_data = rfdata.data with properties: Freq: [202x1 double] S_Parameters: [2x2x202 double] GroupDelay: [202x1 double] NF: [202x1 double] OIP3: [202x1 double] Z0: 50.0000 + 0.0000i ZS: 50.0000 + 0.0000i ZL: 50.0000 + 0.0000i IntpType: 'Linear' Name: 'Data object' fit_data = rfmodel.rational with properties: A: [6x1 double] C: [6x1 double] D: 0 Delay: 0 Name: 'Rational Function'