BPSK.rar_AWGN_AWGN channel_BPSK AWGN channel_bpsk_bpsk awgn

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Author : Rouijel awatif % Email : rawatif@hotmail.com % Date : 30/2/2009 % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% clear N = 10^6 % number of bits or symbols rand('state',100); % initializing the rand() function randn('state',200); % initializing the randn() function % Transmitter ip = rand(1,N)>0.5; % generating 0,1 with equal probability s = 2*ip-1; % BPSK modulation 0 -> -1; 1 -> 0 n = 1/sqrt(2)*[randn(1,N) + j*randn(1,N)]; % white gaussian noise, 0dB variance Eb_N0_dB = [-3:10]; % multiple Eb/N0 values for ii = 1:length(Eb_N0_dB) % Noise addition y = s + 10^(-Eb_N0_dB(ii)/20)*n; % additive white gaussian noise % receiver - hard decision decoding ipHat = real(y)>0; % counting the errors nErr(ii) = size(find([ip- ipHat]),2); end simBer = nErr/N; % simulated ber theoryBer = 0.5*erfc(sqrt(10.^(Eb_N0_dB/10))); % theoretical ber % plot close all figure semilogy(Eb_N0_dB,theoryBer,'b.-'); hold on semilogy(Eb_N0_dB,simBer,'mx-'); axis([-3 10 10^-5 0.5]) grid on legend('theory', 'simulation'); xlabel('Eb/No, dB'); ylabel('Bit Error Rate'); title('courbe de BER (Bit error probability) pour une modulation BPSK');