m3MIMO/qpsk_demodulation.m at master · Restuccia-Group/m3MIMO · GitHub

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% function [rx_bits, corrected_bits] = qpsk_demodulation(rx_symbols)
%     % QPSK Demodulation function with Hamming decoding
%     % Input: rx_symbols - Received QPSK symbols
%     % Output: rx_bits - Demodulated bits
%     %         corrected_bits - Corrected bits after Hamming decoding
%
%     % Demodulate QPSK symbols
%     rx_bits_I = real(rx_symbols) > 0; % Demodulate I-channel: 1 -> 1, 0 -> 0
%     rx_bits_Q = imag(rx_symbols) > 0; % Demodulate Q-channel: 1 -> 1, 0 -> 0
%
%     % Combine demodulated bits
%     rx_bits = zeros(1, 2 * length(rx_symbols));
%     rx_bits(1:2:end) = rx_bits_I;
%     rx_bits(2:2:end) = rx_bits_Q;
%
%     % Ensure the received bits length is a multiple of 7 for Hamming(7,4) decoding
%     n = length(rx_bits);
%     if mod(n, 7) ~= 0
%         error('Received bits length must be a multiple of 7');
%     end
%
%     % Decode received bits using Hamming code
%     corrected_bits = decode(rx_bits, 7, 4, 'hamming/binary');
% end

function [rx_bits, corrected_bits] = qpsk_demodulation(rx_symbols)
    % QPSK Demodulation function with Hamming decoding
    % Input: rx_symbols - Received QPSK symbols
    % Output: rx_bits - Demodulated bits
    %         corrected_bits - Corrected bits after Hamming decoding

    % Demodulate QPSK symbols
    rx_bits_I = real(rx_symbols) > 0; % Demodulate I-channel: 1 -> 1, 0 -> 0
    rx_bits_Q = imag(rx_symbols) > 0; % Demodulate Q-channel: 1 -> 1, 0 -> 0

    % Combine demodulated bits
    rx_bits = zeros(1, 2 * length(rx_symbols));
    rx_bits(1:2:end) = rx_bits_I;
    rx_bits(2:2:end) = rx_bits_Q;

    % Decode received bits using Hamming code
    corrected_bits = decode(rx_bits, 7, 4, 'hamming/binary');
end