7/25/2019 Ber for Bpsk Modulation With Selection Diveristy in Rayleigh Channel

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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 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 selection diversity

clearN = 10^6; % number of bits or symbols

% Transmitterip = rand(1,N)>0.5; % generating 0,1 with equal probabilitys = 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 gaussiannoise, 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;

% finding the power of the channel on all rx chain hPower = h.*conj(h);

% finding the maximum power [hMaxVal ind] = max(hPower,[],1); hMaxValMat = kron(ones(nRx(jj),1),hMaxVal);

% selecting the chain with the maximum power ySel = y(hPower==hMaxValMat); hSel = h(hPower==hMaxValMat);

% equalization with the selected rx chain

yHat = ySel./hSel; yHat = reshape(yHat,1,N); % just to get the matrix dimension proper

% receiver - hard decision decoding ipHat = real(yHat)>0;

% counting the errors nErr(jj,ii) = size(find([ip- ipHat]),2);

end

7/25/2019 Ber for Bpsk Modulation With Selection Diveristy in Rayleigh Channel

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endsimBer = nErr/N; % simulated berEbN0Lin = 10.^(Eb_N0_dB/10);theoryBer_nRx1 = 0.5.*(1-1*(1+1./EbN0Lin).^(-0.5));theoryBer_nRx2 = 0.5.*(1-2*(1+1./EbN0Lin).^(-0.5) + (1+2./EbN0Lin).^(-0.5));

% plotclose allfigure

semilogy(Eb_N0_dB,theoryBer_nRx1,'bp-','LineWidth',2);hold onsemilogy(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 onlegend('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 Selection diveristy in Rayleigh channel');