OQAM_OFDM_IAM2_youhua.rar_OFDM/OQAM_OFDM优化_OQAM信道估计_ofdm-oqam_信道

%------------------论文曲线——有改进--------------------- clear all; tic %-----------------仿真参数---------------------------- fs_filter=2048;%滤波器的采样率 N=2048;%子载波个数 Ns=40;%symbol个数 dsource_buf=zeros(1,2048*Ns-6); dsource=zeros(1,2048*Ns-6); N_frame=2;%仿真次数 SNR=0:1:10; BER=zeros(1,length(SNR)); out_interleaving=zeros(1,163840); out_interleaving1=zeros(2,81920); data=zeros(2048,40); d_source=zeros(2048,80); %---------------产生训练序列------------------------- pilot=zeros(2048,3); for m=1:512 pilot(4*m-3,:)=[0,1,0]; pilot(4*m-2,:)=[0,1,0]; pilot(4*m-1,:)=[0,-1,0]; pilot(4*m,:)=[0,-1,0]; end %-------------- 多径衰落信道：IEEE802.22----------------------------------- SampR = 1/9.14; % 信号速率 9.14M h = zeros(1,round(14/SampR)+1); % 信道冲激响应初始化 h(1) = 10^((-6)/10); h(round(3/SampR)+1) = 1; % 信道长度：6 chips h(round(5/SampR)+1) = 10^((-7.0)/10); h(round(7/SampR)+1) = 10^((-22.0)/10); h(round(10/SampR)+1) = 10^((-16.0)/10); h(round(14/SampR)+1) = 10^((-20.0)/10); %---------------------------------------------------------------------- H=fft(h,N); for isnr=1:length(SNR) count=0; for n_frame=1:N_frame %------------------产生数据符号----------------------------- dsource_buf=randn(1,N*Ns-6); dsource_buf=dsource_buf>0; dsource=[dsource_buf,0,0,0,0,0,0];%生成一帧内的随机二进制比特流，此帧为发送端发送的数据 %----------FEC coder---------- d_trellis=poly2trellis(7,[133 171]); out_fec=convenc(dsource,d_trellis);%编码，输入1bit输出2bit %----------interleaving---------- k=0:163839; %first step interleaving s=10240*mod(k,16)+floor(k/16); out_interleaving(k+1)=out_fec(s+1); for m=1:81920 out_interleaving1(1,m)=out_interleaving(2*m-1); out_interleaving1(2,m)=out_interleaving(2*m); end modObj = modem.pskmod('M',4, 'PhaseOffset',pi/4,'SymbolOrder', 'binary', 'InputType', 'bit'); modulatedsig = modulate(modObj, out_interleaving1); for m=1:40 data(1:2048,m)=modulatedsig(2048*(m-1)+1:2048*m); end %-------------------------------滤波器设计--------------------------------- rolloff=1;%滚降系数 L=4*fs_filter;%滤波器阶数 h_sqrt_nyquist = rcosine(1,fs_filter,'fir/sqrt',rolloff,L/(2*fs_filter));%产生滤波器 % pilot(h_sqrt_nyquist);grid on;hold on %------------------------------发送端------------------------------------ %for m=0:2047 % for n=0:79 % d_source(m+1,n+1)=d_source(m+1,n+1)*exp(i*(m+n)); %end %end %--------------------------------------------------------------- %signal_up=(upsample(d_source.',fs_filter/2)).';%对信号上采样 %signal_filtered=zeros(N,length(signal_up)+length(h_sqrt_nyquist)-1); %for m=1:2048 %signal_filtered(m,:)=conv(signal_up,h_sqrt_nyquist); %end %----------------------------------------------------------------------------- signal_new=zeros(N,2*Ns); signal_real=real(data); signal_imag=imag(data); for m=1:1024 signal_new(2*m-1,1:2:2*Ns-1)=signal_real(2*m-1,:); signal_new(2*m-1,2:2:2*Ns)=signal_imag(2*m-1,:); signal_new(2*m,1:2:2*Ns-1)=signal_imag(2*m,:); signal_new(2*m,2:2:2*Ns)=signal_real(2*m,:); end signal_new_pilot=[pilot,signal_new]; signal_modulation=zeros(N,2*Ns+3); for m=1:N for n=1:2*Ns+3 signal_modulation(m,n)=signal_new_pilot(m,n)*exp(1i*(m+n-2)*pi/2); end end %for n=1:N %signal_modulation(n,:)=signal_new(n,:)*exp(1i*(n-1)*pi/2); %signal_modulation(n,2:2:2*Ns)=signal_modulation(n,2:2:2*Ns)*exp(1i*pi/2); %end signal_ifft=zeros(2*Ns+3,N); signal_filtered=zeros(2*Ns+3,length(h_sqrt_nyquist)); signal_carrier=zeros(2*Ns+3,length(h_sqrt_nyquist)+(2*Ns+3-1)*fs_filter/2); for n=1:2*Ns+3 signal_ifft(n,:)=ifft(signal_modulation(:,n),N)*N; signal_ifft(n,:)=circshift(signal_ifft(n,:).',-N/2*(n-1)).'; signal_filtered(n,1:N)=signal_ifft(n,:).*h_sqrt_nyquist(1:N); signal_filtered(n,N+1:2*N)=signal_ifft(n,:).*h_sqrt_nyquist(N+1:2*N); signal_filtered(n,2*N+1:3*N)=signal_ifft(n,:).*h_sqrt_nyquist(2*N+1:3*N); signal_filtered(n,3*N+1:4*N)=signal_ifft(n,:).*h_sqrt_nyquist(3*N+1:4*N); signal_filtered(n,4*N+1:(length(h_sqrt_nyquist)))=signal_ifft(n,(length(h_sqrt_nyquist)-4*N)).*h_sqrt_nyquist(4*N+1:(length(h_sqrt_nyquist))); signal_filtered_shift=[zeros(1,(n-1)*fs_filter/2),signal_filtered(n,:)]; signal_carrier(n,:)=[signal_filtered_shift,zeros(1,length(signal_carrier)-length(signal_filtered_shift))]; end signal_transmit=sum(signal_carrier); %-------------------------------通过信道------------------------------- out_channel=conv(h,signal_transmit); power=var(signal_transmit); sigma=sqrt(power/(10^(SNR(1,isnr)/10))); power_db=10*log10(power); awgn_signal_transmit=awgn(out_channel,SNR(isnr),power_db); %----------------接收端------------------------------------ signal_received= awgn_signal_transmit(1,1:length(signal_transmit)); h_sqrt_nyquist_shift=zeros(2*Ns+3,length(signal_received)); signal_received_filtered=zeros(2*Ns+3,length(signal_received)); signal_received_filtered1=zeros(2*Ns+3,N*(L/fs_filter+(Ns+1.5))); for n=1:2*Ns+3 h_sqrt_nyquist_temp=[zeros(1,(n-1)*fs_filter/2),h_sqrt_nyquist]; h_sqrt_nyquist_shift(n,:)=[h_sqrt_nyquist_temp,zeros(1,length(signal_received)-length(h_sqrt_nyquist_temp))]; signal_received_filtered(n,:)=h_sqrt_nyquist_shift(n,:).*signal_received; signal_received_filtered1(n,:)=[signal_received_filtered(n,:),zeros(1,length(signal_received_filtered1)-length(signal_received_filtered))]; end signal_received_filtered_new=zeros(2*Ns+3,N); signal_received_fft=zeros(2*Ns+3,N); signal_received_demodulation=zeros(2*Ns+3,N); signal_received_demodulation1=zeros(2*Ns+3,N); for n=1:2*Ns+3 for m=1:N signal_received_filtered_new(n,m)=sum(signal_received_filtered1(n,1+(m-1):N:(N*(L/fs_filter+(Ns+1.5)-1)+(m-1)))); end signal_received_fft(n,:)=fft(signal_received_filtered_new(n,:),N); end for m=1:N for n=1:2*Ns+3 signal_received_demodulation(n,m)=signal_received_fft(n,m)*exp(-1i*(m+n-2)*pi/2); end end %for n=1:N %signal_received_demodulation(:,n)=signal_received_fft(:,n)*exp(-1i*(n-1)*pi/2); %end %signal_received_demodulation1(1:2:2*Ns-1,:)=real(signal_received_demodulation(1:2:2*Ns-1,:)); %signal_received_demodulation1(2:2:2*Ns,:)=real(signal_received_demodulation(2:2:2*Ns,:)); % variance_real=mean((signal_demod_real_filtered_down(:,1:N_symbol).'-real(signal).').^2);%实部信号不同载波上方差 % variance_imag=mean((signal_demod_imag_filtered_down(:,1:N_symbol).'-imag(signal).').^2);%虚部信号不同载波上方差 % variance_r_n(n_time)=mean(variance_real); % variance_i_n(n_time)=mean(variance_imag); signal_final=signal_received_demodulation.'; H_channel=zeros(1,N); H_channel_final=zeros(1,N); %--------------------信道均衡-------------------------------------------- H_channel(1,1)=signal_final(1,2)/(pilot(1,2)+1i*(pilot(1,1)*(-0.5004)+pilot(1,3)*(+0.5004)+pilot(2,1)*0.2501+pilot(2,2)*(-0.3183)+pilot(2,3)*0.2501)); H_channel(1,2)=signal_final(2,2)/(pilot(2,2)+1i*(pilot(1,1)*0.2501+pilot(1,2)*0.3183+pilot(1,3)*0.2501+pilot(2,1)*(-0.5004)+pilot(2,3)*(+0.5004)+pilot(3,1)*0.2501+pilot(3,2)*(-0.3183)+pilot(3,3)*0.2501)); H_channel(1,3)=signal_final(3,2)/(pilot(3,2)+1i*(pilot(2,1)*0.2501+pilot(2,2)*0.3183+pilot(2,3)*0.2501+pilot(3,1)*(-0.5004)+pilot(3,3)*(+0.5004)+pilot(4,1)*0.2501+pilot(4,2)*(-0.3183)+pilot(4,3)*0.2501)); for m=1:681 H_channel(1,3*m+1)=signal_final(3*m+1,2)/(pilot(3*m+1,2)+1i*(p