MRC.rar_combining technique_mrc

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% All rights reserved by Krishna Pillai, http://www.dsplog.com % The file may not be re-distributed without explicit authorization % from Krishna Pillai. % Checked for proper operation with Octave Version 3.0.0 % Author : Krishna Pillai % Email : krishna@dsplog.com % Version : 1.0 % Date : 6th September 2008 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % %Script for computing the BER for BPSK modulation in a % Rayleigh fading channel with Maximal Ratio Combining clear all N = 10^6; % number of bits or symbols % Transmitter ip = rand(1,N)>0.5; % generating 0,1 with equal probability s = 2*ip-1; % BPSK modulation 0 -> -1; 1 -> 0 nRx = [1 2]; Eb_N0_dB = [0:35]; % multiple Eb/N0 values for jj = 1:length(nRx) for ii = 1:length(Eb_N0_dB) n = 1/sqrt(2)*[randn(nRx(jj),N) + j*randn(nRx(jj),N)]; % white gaussian noise, 0dB variance h = 1/sqrt(2)*[randn(nRx(jj),N) + j*randn(nRx(jj),N)]; % Rayleigh channel % Channel and noise Noise addition sD = kron(ones(nRx(jj),1),s); y = h.*sD + 10^(-Eb_N0_dB(ii)/20)*n; % equalization maximal ratio combining yHat = sum(conj(h).*y,1)./sum(h.*conj(h),1); % receiver - hard decision decoding ipHat = real(yHat)>0; % counting the errors nErr(jj,ii) = size(find([ip- ipHat]),2); end end simBer = nErr/N; % simulated ber EbN0Lin = 10.^(Eb_N0_dB/10); theoryBer_nRx1 = 0.5.*(1-1*(1+1./EbN0Lin).^(-0.5)); p = 1/2 - 1/2*(1+1./EbN0Lin).^(-1/2); theoryBer_nRx2 = p.^2.*(1+2*(1-p)); close all figure semilogy(Eb_N0_dB,theoryBer_nRx1,'bp-','LineWidth',2); hold on semilogy(Eb_N0_dB,simBer(1,:),'mo-','LineWidth',2); semilogy(Eb_N0_dB,theoryBer_nRx2,'rd-','LineWidth',2); semilogy(Eb_N0_dB,simBer(2,:),'ks-','LineWidth',2); axis([0 35 10^-5 0.5]) grid on legend('nRx=1 (theory)', 'nRx=1 (sim)', 'nRx=2 (theory)', 'nRx=2 (sim)'); xlabel('Eb/No, dB'); ylabel('Bit Error Rate'); title('BER for BPSK modulation with Maximal Ratio Combining in Rayleigh channel');