- hann - https://www.mathworks.com/help/signal/ref/hann.html
- ftt - https://www.mathworks.com/help/matlab/ref/fft.html
How to calculate S11 from time domain response (TDR)?
57 views (last 30 days)
Show older comments
Hello!
There is an example of calculating the response in the time domain (TDR) for a given reflection coefficient (S11) - https://www.mathworks.com/help/rf/ug/modeling-a-high-speed-backplane-part-3-4-port-s-parameters-to-differential-tdr-and-tdt.html.
How to solve the inverse problem - to find the reflection coefficient (S11) from the time domain response (TDR)?
0 Comments
Answers (1)
Ayush Modi
on 21 Feb 2024
Hi Stepan,
You can calculate the S11 parameter from tdr data by performing Fourier Transform analysis. Here is an example to demonstrate how you can achieve this:
Step 1: Calculate Hann window using "hann" function.
windowed_tdr = tdr .* hann(length(tdr));
Step 2: Calculate fourier transform uisng "fft" function.
% Calculate fft
fft_result = fft(windowed_tdr);
% Process the FFT result
% Normalize the frequency axis
Fs = 1 / (t(2) - t(1)); % Sampling frequency, assuming uniform time step
n = length(fft_result); % Number of points in FFT
f = (0:n-1)*(Fs/n); % Frequency vector
% Scale the FFT result to account for the length of the signal and the window function
fft_scaled = fft_result / (sum(hann(length(tdr))) / length(tdr));
Step 3: Extract s11 parameters
% Extract S11
s11 = fft_scaled(1:n/2); % Take only the first half of the FFT result
s11_magnitude = abs(s11); % Magnitude of S11
s11_phase = angle(s11); % Phase of S11
Please refer to the following MathWorks documentation for more information on:
Hope this helps!
0 Comments
See Also
Categories
Find more on Spectral Measurements in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!