Sherif Mohamed Dec 2018.rar_IM-OFDM_MIMO OFDM 2018_OFDM WITH IM_

clc clear all; close all; % rand('seed',183); randn('seed',321); %% MODEULATION AND DEMODULATION OBJECT M = 4; Eac = 2; taps=10; %% SNR = 0:2:50 ; % signal-to-noise ratio in dB No = (Eac)*10.^(-SNR/10); % noise variance L_SNR = length(SNR); % length of SNR ber = zeros (L_SNR,1); % initializating BER Result_table=zeros(4 ,128); % bit_RL=zeros(L_SNR,1); bit_RLA=zeros(L_SNR,1); Nframe=1000; bit_RL=zeros(L_SNR,1); ; %digMod1=zeros(2 , length(digMod)); ; % initializating BER ab= zeros(2 , 128); Result_table=zeros(4 ,128); block = zeros(4 , 128); ; %% ============================= Transmitter =============================== for iL=1:Nframe % sending 1000 frame bit_T= randi([0 1],512,1); % generate random bits G_bits = reshape(bit_T,4,128); % grouping bits into blocks %% taking the first two rows for index modulation selection Index_selection= [G_bits(1:2,:)].'; %% Doing BPSK modulation for third and fourth rows for G_bits AW=reshape(G_bits(2+1:end,:),1,[]); digMod1 = 2*(AW)-1; digMod=reshape(digMod1,2,[]); % digMod = 2*(G_bits(2+1:end,:))-1; %% Create a block 4x128 to add result for BPSK modulation depending on sub carrier position block = zeros(4 , length(digMod)); ab= zeros(2 , 128); % ML = zeros(1,16); %% Chosing which sub carrier active in each colum for i=1:length(Index_selection) if Index_selection(i,1:end)==[0 0] sub_no(i,1:2)=[1,3]; elseif Index_selection(i,1:2)==[0 1] sub_no(i,1:2)=[2,4]; elseif Index_selection(i,1:2)==[1 0] sub_no(i,1:2)=[1,4]; elseif Index_selection(i,1:end)==[1 1] sub_no(i,1:2)=[2,3]; end %% Adding the modulated signal on active carriers block(sub_no(i,1:2) , i)=digMod(1:2,i); end transmitted_signa =block; % transmitted_signal %% Pass the signal through IFFT transmitted_signa1=reshape(transmitted_signa,512,1); IFFT_data = ifft(fftshift(transmitted_signa1.')).'; % IFFT_data = ifft((transmitted_signa1)); a=max(max(abs(IFFT_data))); transmitted_signa_IFFT=IFFT_data./a; % normalization %% % transmitted sinal with IFFT transmitted_signa_IFFTB=reshape(transmitted_signa_IFFT,4,128); %% Appending cylic prefix transmitted_signa_IFFTC = [transmitted_signa_IFFTB(:,[113:128]) transmitted_signa_IFFTB]; transmitted_signa_IFFTD=reshape(transmitted_signa_IFFTC,[],1); %% Calling a table for all posible position for BPSK modulation in INdex modaulation table=BPSKAA; % for iL=1:Nframe %% Creating a channel and receiver ber=[]; for ii =1: L_SNR % for pp = 1 :128 %% Creating channel and noise ch = sqrt(.5)*( randn(1,1,1) + 1i*randn(1,1,1)); % No = 1/10^(SNR(ii)/10); % noise = sqrt(.5)*(randn(1 , 1) + 1i*randn(1 , 1))* sqrt(No); % white gaussian noise, 0dB variance % ch = 1/sqrt(2)*[randn(1,1) + j*randn(1,1)]; % Rayleigh fading channel %% Passing signal through noise amd channel % % % received_signal = ch.*transmitted_signa_IFFT + noise; % received_signal=received_signal./ch; % transmitted_signa_IFFT=reshape(transmitted_signa_IFFT,1,512); % ch = 1/sqrt(2)*[randn(1,length(transmitted_signa_IFFT)) + j*randn(1,length(transmitted_signa_IFFT))]; % % Send over Gaussian Link to the receiver % received_signal = ch.*transmitted_signa_IFFT + sqrt(No/2)*(randn(1,length(transmitted_signa_IFFT))+i*randn(1,length(transmitted_signa_IFFT))); noise = sqrt(.5)*(randn(1 , 1) + 1i*randn(1 , 1))* sqrt(No(ii)); %--------------------------------------------------------------- % Equalization to remove fading effects. Ideal Equalization % Considered % received_signal = received_signal./ch; % received_signalY=awgn( (ch.*transmitted_signa_IFFTD),SNR(ii)); % received_signal=reshape(received_signal,512,1); % received_signalER=reshape(received_signalY,4,144); received=(ch.*transmitted_signa_IFFTD) + noise; received_signalER=reshape(received,4,144); %% removing cyclic prefix received_signalA = received_signalER(:,[17:144]); received_signal=reshape(received_signalA,[],1); %% Applying FFT and normalize the signal % received_signal=reshape(received_signal,4,128); received_signal1 = a.*fftshift(fft(received_signal.' )).'; % received_signal1 = a.*fft((received_signal )); received_signal2=reshape(received_signal1,4,128); for pp= 1 : 128 %% Maximum Likelihood ML = zeros(1,16); A=received_signal2(:,pp); B= repmat(A,[1,16]); % AAA=awgn(table,SNR(ii)); %ch* ML= sum(abs( (B) - (table)).^2); % % % [temp1 temp2] = min(ML); KL(pp)=temp2; % %% finding which sub carrier active in each colum if ( KL(pp)>=1 && KL(pp)<=4) P_sub_B(pp,1:2)= [1,3]; GET_INDEX_Selec(pp,1:2)=[0,0]; elseif ( KL(pp)>=5 && KL(pp)<=8) P_sub_B(pp,1:2)=[2,4]; GET_INDEX_Selec(pp,1:2)=[0,1]; elseif ( KL(pp)>=9 && KL(pp)<=12) P_sub_B(pp,1:2)=[1,4]; GET_INDEX_Selec(pp,1:2)=[1,0]; elseif ( KL(pp)>=13 && KL(pp)<=16) P_sub_B(pp,1:2)=[2,3]; GET_INDEX_Selec(pp,1:2)=[1,1]; end AC_subcarrier=P_sub_B; %%chosing the two colum for the postion os subcarrier %% Demodulate the transmiited_signal using the Index selection bits you detected in receiver after you chose for the first colum ab(1:2,pp)= (block(AC_subcarrier(pp,1:2),pp)); % converting modulated values into 0 and 1 bi_demod(1:2,pp) = ( (ab(1:2,pp))+1)/2 ; %% Creating a Result_table 4x128 after you detected the INdex selection bits and demodulated signal bits % % % GET_INDEX_Selec1=GET_INDEX_Selec(pp,1:2).'; bi_demod1= bi_demod(1:2,pp); % % % %% Creating a Result_table 4x128 after you detected the INdex selection bits and demodulated signal bits % % % Result_table(:,pp)=[ GET_INDEX_Selec1; bi_demod1]; end bit_R=reshape( floor(Result_table),512,1); [~,ber(ii,1)] = biterr(bit_T(:,1),bit_R(:)); end %% Adding the previous ber for thw previous frame with the next frame after it bit_RL= bit_RL+ ber; end bit_RL=bit_RL/Nframe; semilogy(SNR,bit_RL(:,1),'-','LineWidth',2); grid on; % % hold on; % % theoryBer = (1/4)*3/2*erfc(sqrt(4*0.1*(10.^(SNR/10)))); % % semilogy(SNR,theoryBer ,'--b','linewidth',2); % % axis([0 15 10^-5 1])