球形译码算法在5G通信系统中的应用.matlab2021a运行测试

function softBits = nrSoftModuDemapper(symbsIn,moduType,N0,method) % nrSoftModuDemapper demodulates symbols to soft bits % softBits = nrSoftModuDemapper(symbsIn,moduType,N0,method) demodulates the complex symbols % symbsIn using soft decision. The modulation scheme, moduType must be one % of 'BPSK', 'QPSK', '16QAM', '64QAM', '256QAM'. symbsIn must be % a column vector. % 'mothod' - Specified as 'max-log-map' or 'approx'. % % Demodulation is performed according to the constellations given in % TS 38.211 section 5.1 including the power normalization factors % specified. % % Source Paper: Mao, Juquan, et al. "A low complexity 256QAM soft demapper for 5G mobile system." % Author: Dr J Mao % Email: juquan.justin.mao@gmail.com % Date: 2021 Nov % Example: % %Demonstrates 16-QAM demodulation. % msg = randi([0 1],100,1,'int8'); % symb = nrModuMapper(msg,'16QAM'); % N0 = 0.1; % rxsymb = symb + sqrt(N0/2)*randn(size(symb)) ; % msg_hat = nrSoftModuDemapper(msg_hat,'16QAM',N0,'max-log-map'); % numErr = sum(msg ~=(msg_hat < 0)); N0 = max(N0,0.001); switch lower(moduType) case 'bpsk' softBits = 4/N0 * real(exp(-1j*pi/4)*symbsIn); case 'qpsk' softBits = zeros(2,length(symbsIn)); A = 1/sqrt(2); softBits(1,:) = 4*A/N0 * real(symbsIn); softBits(2,:) = 4*A/N0 * imag(symbsIn); softBits = softBits(:); case '16qam' softBits = qam16SoftDemodulation(symbsIn,N0,method); case '64qam' softBits = qam64SoftDemodulation(symbsIn,N0,method); case '256qam' softBits = qam256SoftDemodulation(symbsIn,N0,method); end end %%============================================================= % 16QAM %%============================================================= function softBits = qam16SoftDemodulation(symbsIn,N0,method) softBits = zeros(4,length(symbsIn)); A = 1/sqrt(10); reX = real(symbsIn); imX = imag(symbsIn); if strcmpi(method,'approx') softBits(1,:) = 4*A/N0 * reX; softBits(2,:) = 4*A/N0 * imX; else % max-log-MAP softBits(1,:) = maxLogMapQam16SoftDemodulation_1_2(reX,N0); softBits(2,:) = maxLogMapQam16SoftDemodulation_1_2(imX,N0); end softBits(3,:) = 4*A/N0 * (-abs(reX)+ 2*A); softBits(4,:) = 4*A/N0 * (-abs(imX)+ 2*A); softBits = softBits(:); end function softBits = maxLogMapQam16SoftDemodulation_1_2(realSymbIn, N0) A = 1/sqrt(10); X = realSymbIn; Y = zeros(size(X)); for i = 1: length(X) if X(i) < -2*A Y(i) = 8*A/N0 * (X(i) + A); elseif X(i) < 2*A Y(i) = 4*A/N0 * X(i); else Y(i) = 8*A/N0 * (X(i) - A); end end softBits = Y; end %%============================================================= % 64QAM %%============================================================= function softBits = qam64SoftDemodulation(symbsIn,N0,method) softBits = zeros(4,length(symbsIn)); A = 1/sqrt(42); reX = real(symbsIn); imX = imag(symbsIn); if strcmpi(method,'approx') softBits(1,:) = 4*A/N0 * reX; softBits(2,:) = 4*A/N0 * imX; softBits(3,:) = 4*A/N0 * (-abs(reX) + 4*A); softBits(4,:) = 4*A/N0 * (-abs(imX) + 4*A); else % max-log-MAP softBits(1,:) = maxLogMapQam64SoftDemodulation_1_2(reX, N0); softBits(2,:) = maxLogMapQam64SoftDemodulation_1_2(imX, N0); softBits(3,:) = maxLogMapQam64SoftDemodulation_3_4(reX, N0); softBits(4,:) = maxLogMapQam64SoftDemodulation_3_4(imX, N0); end softBits(5,:) = 4*A/N0 * (-abs(-abs(reX)+ 4*A)+2*A); softBits(6,:) = 4*A/N0 * (-abs(-abs(imX)+ 4*A)+2*A); softBits = softBits(:); end function softBits = maxLogMapQam64SoftDemodulation_1_2(realSymbIn, N0) A = 1/sqrt(42); X = realSymbIn; Y = zeros(size(X)); for i = 1: length(X) if X(i) < -6*A Y(i) = 16*A/N0 * (X(i) + 3*A); elseif X(i) < -4*A Y(i) = 12*A/N0 * (X(i) + 2*A); elseif X(i) < -2*A Y(i) = 8*A/N0 * (X(i) + A); elseif X(i) < 2*A Y(i) = 4*A/N0 * X(i) ; elseif X(i) < 4*A Y(i) = 8*A/N0 * (X(i) - A); elseif X(i) < 6*A Y(i) = 12*A/N0 * (X(i) - 2*A); else Y(i) = 16*A/N0 * (X(i) - 3*A); end end softBits = Y; end function softBits = maxLogMapQam64SoftDemodulation_3_4(realSymbIn, N0) A = 1/sqrt(42); X = realSymbIn; Y = zeros(size(X)); for i = 1: length(X) if X(i) < -6*A Y(i) = 8*A/N0 * (X(i) + 5*A); elseif X(i) < -2*A Y(i) = 4*A/N0 * (X(i) + 4*A); elseif X(i) < 0 Y(i) = 8*A/N0 * (X(i) + 3*A); elseif X(i) < 2*A Y(i) = 8*A/N0 * (-X(i) + 3*A); elseif X(i) < 6*A Y(i) = 4*A/N0 * (-X(i) + 4*A); else Y(i) = 8*A/N0 * (-X(i) + 5*A); end end softBits = Y; end %%============================================================= % 256QAM %%============================================================= function softBits = qam256SoftDemodulation(symbsIn,N0,method) softBits = zeros(8,length(symbsIn)); A = 1/sqrt(170); reX = real(symbsIn); imX = imag(symbsIn); if strcmpi(method,'approx') softBits(1,:) = 4*A/N0 * reX; softBits(2,:) = 4*A/N0 * imX; softBits(3,:) = 4*A/N0 * (-abs(reX) + 8*A); softBits(4,:) = 4*A/N0 * (-abs(imX) + 8*A); softBits(5,:) = 4*A/N0 * (-abs(-abs(reX)+8*A) + 4*A); softBits(6,:) = 4*A/N0 * (-abs(-abs(imX)+8*A) + 4*A); else % max-log-MAP softBits(1,:) = maxLogMapQam256SoftDemodulation_1_2(reX, N0); softBits(2,:) = maxLogMapQam256SoftDemodulation_1_2(imX, N0); softBits(3,:) = maxLogMapQam256SoftDemodulation_3_4(reX, N0); softBits(4,:) = maxLogMapQam256SoftDemodulation_3_4(imX, N0); softBits(5,:) = maxLogMapQam256SoftDemodulation_5_6(reX, N0); softBits(6,:) = maxLogMapQam256SoftDemodulation_5_6(imX, N0); end softBits(7,:) = 4*A/N0 * (-abs(-abs(-abs(reX)+8*A) + 4*A)+2*A); softBits(8,:) = 4*A/N0 * (-abs(-abs(-abs(imX)+8*A) + 4*A)+2*A); softBits = softBits(:); end function softBits = maxLogMapQam256SoftDemodulation_1_2(realSymbIn, N0) A = 1/sqrt(170); X = realSymbIn; Y = zeros(size(X)); for i = 1: length(X) if X(i) < -14*A Y(i) = 32*A/N0 * (X(i) + 7*A); elseif X(i) < -12*A Y(i) = 28*A/N0 * (X(i) + 6*A); elseif X(i) < -10*A Y(i) = 24*A/N0 * (X(i) + 5*A); elseif X(i) < -8*A Y(i) = 20*A/N0 * (X(i) + 4*A); elseif X(i) < -6*A Y(i) = 16*A/N0 * (X(i) + 3*A); elseif X(i) < -4*A Y(i) = 12*A/N0 * (X(i) + 2*A); elseif X(i) < -2*A Y(i) = 8*A/N0 * (X(i) + A); elseif X(i) < 2*A Y(i) = 4*A/N0 * X(i); elseif X(i) < 4*A Y(i) = 8*A/N0 * (X(i) - A); elseif X(i) < 6*A Y(i) = 12*A/N0 * (X(i) - 2*A); elseif X(i) < 8*A Y(i) = 16*A/N0 * (X(i) - 3*A); elseif X(i) < 10*A Y(i) = 20*A/N0 * (X(i) - 4*A); elseif X(i) < 12*A Y(i) = 24*A/N0 * (X(i) - 5*A); elseif X(i) < 14*A Y(i) = 28*A/N0 * (X(i) - 6*A); else Y(i) = 32*A/N0 * (X(i) - 7*A); end end softBits = Y; end function softBits = maxLogMapQam256SoftDemodulation_3_4(realSymbIn, N0) A = 1/sqrt(170); X = realSymbIn; Y = zeros(size(X)); for i = 1: length(X) if X(i) < -14*A Y(i) = 16*A/N0 * (X(i) + 11*A); elseif X(i) < -12*A Y(i) = 12*A/N0 * (X(i) + 10*A); elseif X(