基于MATLAB的MIMO-OFDMA系统的设计与仿真-毕业论文

南京林业大学本科生毕业设计（论文）

XX((con_r-1)*carrier_count+1:con_r*carrier_count,con_c)=conj(data((abs(real(O(con_r,con_c)))-1)*carrier_count+1:abs(real(O(con_r,con_c)))...

*carrier_count,1))*sign(real(O(con_r,con_c))); end end end

end

XX=[tx_training_symbols;XX];

rx_buf=zeros(1,addprefix_length*(co_time+1),Nr); for rev=1:Nr for ii=1:Nt

tx_buf=reshape(XX(:,ii),carrier_count,co_time+1); IFFT_tx_buf=zeros(IFFT_bin_length,co_time+1); IFFT_tx_buf(carriers,:)=tx_buf(1:carrier_count,:);

IFFT_tx_buf(conjugate_carriers,:)=conj(tx_buf(1:carrier_count,:)); time_matrix=ifft(IFFT_tx_buf);

time_matrix=[time_matrix((IFFT_bin_length-cp_length+1):IFFT_bin_length,:);time_matrix];

tx=time_matrix(:)';

%------------------------------------------------------------------------ %d=randint(1,4,[1,7]); %a=randint(1,4,[2,7])/10; tx_tmp=tx;

d=[4,5,6,2;4,5,6,2;4,5,6,2;4,5,6,2];

a=[0.2,0.3,0.4,0.5;0.2,0.3,0.4,0.5;0.2,0.3,0.4,0.5;0.2,0.3,0.4,0.5]; for jj=1:size(d,2)

copy=zeros(size(tx)) ;

for kk = 1 + d(ii,jj): length(tx)

copy(kk) = a(ii,jj)*tx(kk - d(ii,jj)) ; end

tx_tmp=tx_tmp+copy; end

%------------------------------------------------------------------------

txch=awgn(tx_tmp,SNR,'measured');

rx_buf(1,:,rev)=rx_buf(1,:,rev)+txch;

end

rx_spectrum=reshape(rx_buf(1,:,rev),addprefix_length,co_time+1); rx_spectrum=rx_spectrum(cp_length+1:addprefix_length,:);

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南京林业大学本科生毕业设计（论文）

FFT_tx_buf=zeros(IFFT_bin_length,co_time+1); FFT_tx_buf=fft(rx_spectrum);

spectrum_matrix=FFT_tx_buf(carriers,:); Y_buf=(spectrum_matrix(:,2:co_time+1)); Y_buf=conj(Y_buf');

spectrum_matrix1=spectrum_matrix(:,1); Wk=exp((-2*pi/carrier_count)*i); L=10;

p=zeros(L*Nt,1); for jj=1:Nt

for l=0:L-1

for kk=0:carrier_count-1

p(l+(jj-1)*L+1,1)=p(l+(jj-1)*L+1,1)+spectrum_matrix1(kk+1,1)*conj(tx_training_symbols(kk+1,jj))*Wk^(-(kk*l)); end end end

h=p/carrier_count;

H_buf=zeros(carrier_count,Nt); for ii=1:Nt

for kk=0:carrier_count-1 for l=0:L-1

H_buf(kk+1,ii)=H_buf(kk+1,ii)+h(l+(ii-1)*L+1,1)*Wk^(kk*l); end end end

H_buf=conj(H_buf');

RRR=[];

for kk=1:carrier_count Y=Y_buf(:,kk); H=H_buf(:,kk); for co_ii=1:num_X

for co_tt=1:size(eta,2) if eta(co_ii,co_tt)~=0

if coj_mt(eta(co_ii,co_tt),co_ii)==0

r_til(eta(co_ii,co_tt),:,co_ii)=Y(eta(co_ii,co_tt),:);

a_til(eta(co_ii,co_tt),:,co_ii)=conj(H(epsilon(eta(co_ii,co_tt),co_ii),:));

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南京林业大学本科生毕业设计（论文）

else

r_til(eta(co_ii,co_tt),:,co_ii)=conj(Y(eta(co_ii,co_tt),:));

a_til(eta(co_ii,co_tt),:,co_ii)=H(epsilon(eta(co_ii,co_tt),co_ii),:); end end end end

RR=zeros(num_X,1); for

iii=1:num_X %Generate decision statistics for the transmitted signal \ for ttt=1:size(eta,2) if eta(iii,ttt)~=0

RR(iii,1)=RR(iii,1)+r_til(eta(iii,ttt),1,iii)*a_til(eta(iii,ttt),1,iii)*delta(eta(iii,ttt),iii); end end end

RRR=[RRR;conj(RR')]; end

r_sym=pskdemod(RRR,M_psk,0);

re_met_sym_buf(:,tt:tt+Nt-1,rev)=r_sym; end end

re_met_sym=zeros(baseband_out_length,1,Nr);

for rev=1:Nr

re_met_sym_buf_buf=re_met_sym_buf(:,:,rev); re_met_sym(:,1,rev)= re_met_sym_buf_buf(:); re_met_bit(:,:,rev)=de2bi(re_met_sym(:,1,rev));

for con_dec_ro=1:baseband_out_length if re_met_sym(con_dec_ro,1,rev)~=de_data(con_dec_ro,1) n_err_sym(1,rev)=n_err_sym(1,rev)+1; for con_dec_co=1:bits_per_symbol if

re_met_bit(con_dec_ro,con_dec_co,rev)~=baseband_out(con_dec_ro,con_dec_co) n_err_bit(1,rev)=n_err_bit(1,rev)+1; end

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南京林业大学本科生毕业设计（论文）

end end end

graph_inf_sym(SNR-snr_min+1,1,rev)=SNR; graph_inf_bit(SNR-snr_min+1,1,rev)=SNR;

Perr_sym(1,rev)=n_err_sym(1,rev)/(baseband_out_length);

%Count number of error bits and symbols

graph_inf_sym(SNR-snr_min+1,2,rev)=Perr_sym(1,rev);

Perr_bit(1,rev)=n_err_bit(1,rev)/(baseband_out_length*bits_per_symbol); graph_inf_bit(SNR-snr_min+1,2,rev)=Perr_bit(1,rev); end end

for rev=1:rev

x_sym=graph_inf_sym(:,1,rev);

%Generate plot

y_sym=graph_inf_sym(:,2,rev); subplot(Nr,1,rev);

semilogy(x_sym,y_sym,'k-v'); axis([2 16 0.0001 1]); xlabel('SNR, [dB]');

ylabel('Symbol Error Probability'); grid on %hold on end

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