【正文】 end end % for j end % for nfunction vHat = decodeProbDomain(rx, H, N0, iteration)% Probabilitydomain sum product algorithm LDPC decoder%% rx : Received signal vector (column vector)% H : LDPC matrix% N0 : Noise variance% iteration : Number of iteration%% vHat 。30 end end % for k % Bit decoding if numOfOnes + ci(j) = length(r1) numOfOnes vHat(j) = 1。, excluding r1(k) if numOfOnes + ci(j) = length(r1) numOfOnes + rji(r1(k), j) qij(r1(k), j) = 1。 for majority of 1s else 39。 for k = 1:length(r1) % Update qij, set 39。 end % for k end % for i % Vertical step for j = 1:N % Find nonzero in the row r1 = find(H(:, j))。 % Horizontal step for i = 1:M % Find nonzeros in the column c1 = find(H(i, :))。Iteration : %d\n39。% Asscociate the ci matrix with nonzero elements of Hqij = H.*repmat(ci, M, 1)。) + 1)。function vHat = decodeBitFlipping(rx, H, iteration)% Harddecision/bit flipping sum product algorithm LDPC decoder%29% rx : Received signal vector (column vector)% H : LDPC matrix% iteration : Number of iteration%% vHat : Decoded vector (0/1) %%% Copyright Bagawan S. Nugroho, 2022 % [M N] = size(H)。Message encoded.\n39。 % Return the rearrange H newH = H。 end % if end % for i% Find z = mod(H(:, (N M) + 1:end)*dSource, 2)。 % There will be no rows operation at the last row if i M % Find the later rows with nonzero elements in column i [r2, c2] = find(F((i + 1):end, i))。 % Fill the LU matrices column by column L(i:end, i) = F(i:end, i)。 F(:, chosenCol) = tmp1。 F(:, i) = F(:, chosenCol)。 end % switch % Reordering columns of both H and F tmp1 = F(:, i)。Please select columns reordering strategy!\n39。 % Add offset to the chosen row index to match the dimension of the... % original matrix F chosenCol = c(rowIndex(ix)) + (i 1)。 % Find nonzero diagonal element candidates rowIndex = find(r == i)。 colWeight = sum(F(:, i:end), 1) 1。Minprod39。 % Add offset to the chosen row index to match the dimension of the... % original matrix F chosenCol = c(rowIndex(ix)) + (i 1)。 % Find nonzero diagonal element candidates rowIndex = find(r == i)。 strategy case {1} % Find nonzero elements (1s) for the diagonal [r, c] = find(F(:, i:end))。 % Create diagonally structured matrix using 39。 % Find nonzero diagonal element candidates rowIndex = find(r == i)。First39。 1 = Mincol。U = zeros(M, N M)。% Set a new matrix F for LU depositionF = H。)。 end end % if end % if end % for j end % for i end % iffprintf(39。 if lc 1 % If found, flip one 1 to 0 in the row with less number of 1s if length(find(H(i, :))) length(find(H(j, :))) % Repeat the process until only one column left for cc = 1:lc 1 H(j, c1(cc)) = 0。 c1 = find(w)。 % Add one 1 if row has only one 1 elseif length(find(r == i)) == 1 H(i, n(1)) = 1。 % Add two 1s if row has no 1 if length(find(r == i)) == 0 H(i, n(1)) = 1。26 H = full(S)。 r = reshape(tmp, N*onePerCol, 1)。 % Order column index based on row index for i = 1:N*onePerCol cSort(i, :) = c(ix(i))。 c = reshape(tmp, N*onePerCol, 1)。 end % Create non zero elements (1s) index r = reshape(onesInCol(1:onePerCol, :), N*onePerCol, 1)。 % Create sparse matrix H H = full(sparse(r, c, 1, M, N))。 tmp = repmat([1:N], onePerCol, 1)。switch method % Evencol case {0} % Distribute 1s uniformly at random within column for i = 1:N onesInCol(:, i) = randperm(M)39。Creating LDPC matrix...\n39。endonePerRow = (N/M)*onePerCol。Code rate must be 1/2\n39。hold off。)。semilogy(EbN0, ber2, 39。)。 end % for i% Plot the resultsemilogy(EbN0, ber1, 39。 end % for j % Get average of BER ber1(i) = ber1(i)/frame。, u)。 ber1(i) = (ber1(i) + rat1)。 % Get bit error rate (for brevity, BER calculation includes parity bits) [num1, rat1] = biterr(vhat139。 vhat2 = decodeLogDomainSimple(tx, newH, iter)。 % Decoding (select decoding method) %vhat = decodeProbDomain(tx, H, newN0, iter)。 % Additional white gaussian noise N0 = 1/(exp(EbN0(i)*log(10)/10))。 dSource(:, j)]。 % Encoding message [c, newH] = makeParityChk(dSource(:, j), H, strategy)。Frame : %d\n39。 % Make random data (0/1) dSource = round(rand(M, frame))。for i = 1:length(EbN0) ber1(i) = 0。% Number of frame (N bits per frame)frame = 10。% Number of iteration。 2 = Minprod)strategy = 2。% LDPC matrix reorder strategy (0 = First。% Eliminate length4 cyclenoCycle = 1。% Method for creating LDPC matrix (0 = Evencol。% LDPC matrix size, rate must be 1/2% Warning: encoding decoding can be very long for large LDPC matrix!M = 1000。致 謝22參考文獻(xiàn)[1] 賀鶴云. LDPC 碼基礎(chǔ)與應(yīng)用. 人民郵電出版社,2022[2] 袁東風(fēng), 張海剛. LDPC 碼理論與應(yīng)用, 人民郵電出版社,2022[3] 符初生,周亮,文紅. LDPC 碼原理與應(yīng)用. 電子科技大學(xué)出版社,2022[4] （美）傳特. 通信系統(tǒng)仿真原理與無線應(yīng)用. 機械工業(yè)出版社,2022[5] 周建興. MATLAB 從入門到精通. 人民郵電出版社, 2022[6] （美）亨塞爾曼， （美）利特菲爾德. 精通 Matlab 7. 清華大學(xué)出版社,2022