WUID
Member level 2
Hi all
I am doing for my final year project a simulation with OFDM system.
i needed a fast function to calculate the LLR, so
I found this code on mathworks,
https://www.mathworks.com/matlabcentral/fileexchange/30110-calculation-of-llr-values-with-variable-noise-variance/content/test_sim.m
the code is working great, but i having difficult to understand the last line:
% do demodulation (with variable NOISE_VAR sigma_n2./abs(H).^2)
llr = calc_llr(llr_demod_obj, r_hat, sigma_n2./abs(H).^2);
why he divided sigma_n2 by the H?
and does it means that I should divide my estimated Noise power by the estimated Channel (did that in my simulation)
it's very important to me to know how to explain this line,
thanks in advance
I am doing for my final year project a simulation with OFDM system.
i needed a fast function to calculate the LLR, so
I found this code on mathworks,
https://www.mathworks.com/matlabcentral/fileexchange/30110-calculation-of-llr-values-with-variable-noise-variance/content/test_sim.m
the code is working great, but i having difficult to understand the last line:
% do demodulation (with variable NOISE_VAR sigma_n2./abs(H).^2)
llr = calc_llr(llr_demod_obj, r_hat, sigma_n2./abs(H).^2);
why he divided sigma_n2 by the H?
and does it means that I should divide my estimated Noise power by the estimated Channel (did that in my simulation)
it's very important to me to know how to explain this line,
thanks in advance
