How do I export data from an .s2p file in MATLAB?

Hi,

I have a sequence of .s2p touchstone files that I need to analyze data from. I am currently using the RF toolbox and have used these commands to export the data:

%load in touchstone s2p data file

data = read(rfdata.data,myfilename);

%sort by data

freq = data.Freq;

s_params = extract(data,'S_PARAMETERS',50);

% data

s11 = s_params(1,1,:);

s22 = s_params(2,2,:);

s21 = s_params(2,1,:);

s12 = s_params(1,2,:);

However, I'd prefer to export the data in a more manual way and not use the toolbox command, because I'm not sure if it is identifying the correct columns of data... it doesn't make 100% sense when I do this. Is there a way I can open the file and import the file as a matrix then seperate out the data? I'm thinking of using something like this:

f = myfilename(:,1); ReS11 = myfilename(:,2); ImS11 = myfilename(:,3); ReS21 = myfilename(:,4); ImS21 = myfilename(:,5); ReS12 = myfilename(:,6); ImS12 = myfilename(:,7); ReS22 = myfilename(:,8); ImS22 = myfilename(:,9);

%Creating the S Parameter Matrix

s11=ReS11+1i*(ImS11);

s12=ReS12+1i*(ImS12);

s21=ReS21+1i*(ImS21);

s22=ReS22+1i*(ImS22);

I just am not sure how to actually get the data imported into my MATLAB script in an automated way. Please help!

Thanks,

[Walter Roberson]

https://www.mathworks.com/matlabcentral/answers/109467-reading-an-s2p-file-issues

The full file format appears to be described at http://na.support.keysight.com/plts/help/WebHelp/FilePrint/SnP_File_Format.htm

[Alexandria Will-Cole]

I understand the file format of touchstone files, but my coding in MATLAB is still novice. I just want to know how to import the .s2p file into MATLAB without using the RF Toolbox in MATLAB, because it is not importing correctly. How can I do this manually in MATLAB?I also want my code to be fairly generic in case I want to change languages from MATLAB to something like python.

Answer 1

[Mark]

The RF Toolbox offers an sparameters object that can read in and manipulate data from Touchstone files

Calculate S-parameters for RF data, network, circuit, and matching network objects - MATLAB sparameters (mathworks.com)

>> obj = sparameters('passive.s2p')

obj =

sparameters: S-parameters object

NumPorts: 2

Frequencies: [202×1 double]

Parameters: [2×2×202 double]

Impedance: 50

rfparam(obj,i,j) returns S-parameter Sij

The RF Toolbox also offers many functions for manipulating and plotting S-parameter data.

Answer 2

[Alexandria Will-Cole]

Okay, I just noticed the first link. The only problem I have with that is that they are reading in a text file. Do you know how I can change the file extension on my .s2p files within my script? There are too many to do prior to the code.