Files
imdd_silas/Functions/Metrics/calc_snr.m
Silas Oettinghaus 5dbc48abc0 Many changes here and there. I lost track... :-(
Current work is on MLSE and SD Decoding etc. MLSE is currently not 100% working, the scalings are maybe off?!
2025-08-11 07:42:04 +02:00

45 lines
1.6 KiB
Matlab

function [snr_all, snr_per_level] = calc_snr(tx_signal, eq_noise)
% CALC_SNR Calculates overall SNR and level-wise SNR for a PAM-M constellation.
%
% [snr_all, snr_per_level] = calc_snr(tx_signal, eq_noise)
%
% Inputs:
% tx_signal - Vector of transmitted signal values.
% eq_noise - Vector of corresponding noise samples.
%
% Outputs:
% snr_all - Overall SNR computed using all signal values.
% snr_per_level - A vector where each element is the SNR computed
% for a unique amplitude level in tx_signal.
%
% The function first computes the overall SNR using the full signal vectors.
% Then it uses the unique levels in tx_signal to calculate the SNR for
% the symbols corresponding to each level separately.
if isa(tx_signal,'Signal')
tx_signal = tx_signal.signal;
end
if isa(eq_noise,'Signal')
eq_noise = eq_noise.signal;
end
% Calculate overall SNR using the complete signals
snr_all = snr(tx_signal, eq_noise);
% Get the unique amplitude levels in the transmitted signal
levels = unique(tx_signal);
% Preallocate an array to store the SNR for each unique level
% Loop over each unique level to compute the SNR for that level
for i = 1:length(levels)
% Find indices where tx_signal equals the current level
idx = (tx_signal == levels(i));
% Compute the SNR for these indices
snr_per_level(i) = snr(tx_signal(idx), eq_noise(idx));
histogram(eq_noise(idx));
end
end