matlab-多径衰落信道中仿真其对相关峰的影响,信号为BOC调制信号,相关峰采用CA码产生-源码

clc; clear; close all; warning off; addpath(genpath(pwd)); c=CA_code(1);% generate CA code L_CA=length(c); m=1;k=1;%BOC modulation settings Rc=k*1.023e6;% code rate Tc=1/Rc;% chip width f_sample=500e6; T_sample=1/f_sample; Tp=1e-3-T_sample; fs=m*1.023e6; Ts=1/fs/2; %% multipath parameters MDR_dB=-6; MDR=10^(MDR_dB/20); % delay_t=linspace(0,1.2*Tc,N_C); delay_t = 0.1*Tc; %% BW=200*1.023e6;d=0.5*Tc;% front end filter and correlator spacing settings % filter N_BW=10000; f=linspace(-BW/2,BW/2,N_BW); PSD_BOC=PSDcal_BOCs(f, fs, Tc); power_loss_filter_dB=10*log10(trapz(f,PSD_BOC)); %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %% C=1;%number of CNo C_N0_dB=20-power_loss_filter_dB; C_N0=10.^(C_N0_dB/10); N0=C/C_N0;% noise power %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% I_NoisePower=0;% Q_NoisePower=0; %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %% N_tao=201; tao=linspace(-1.5*Tc,1.5*Tc,N_tao); R_BPSK_like_multipath_added=zeros(1,N_tao); %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %% t_begin=0; t_end = t_begin+Tp; [S_CA_receiver,t_receiver]=yt_BPSK_function(c,t_begin,t_begin+Tp,Tc,f_sample); h_wait=waitbar(0); for k=1:N_tao % for k=251 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% [s_E,t_E]=yt_BPSK_function(c,t_begin-tao(k)+d/2,t_begin-tao(k)+Tp+d/2,Tc,f_sample); [s_P,t_P]=yt_BPSK_function(c,t_begin-tao(k),t_begin-tao(k)+Tp,Tc,f_sample); [s_L,t_L]=yt_BPSK_function(c,t_begin-tao(k)-d/2,t_begin-tao(k)+Tp-d/2,Tc,f_sample); %% N_zong=length(t_P); % S_receiver_I=sqrt(2*C)*S_CA_receiver+sqrt(I_NoisePower)*randn(1,N_zong); %% multipath added signal [S_CA_receiver_multipath,t]=yt_BPSK_function(c,t_begin-delay_t,t_end-delay_t,Tc,f_sample); S_CA_receiver_multipath_added=S_CA_receiver+MDR*S_CA_receiver_multipath; S_receiver_I1=S_CA_receiver_multipath_added; S_receiver_Q1=0*randn(1,N_zong); fft_sig = fft((S_receiver_I1 + 1i*S_receiver_Q1)); L_res = round(BW/f_sample/2*N_zong); fft_sig(L_res+1:end-L_res) = 0; sigBandL = ifft(fft_sig); RecSigI_multipath_added = real(sigBandL); RecSigQ_multipath_added = imag(sigBandL); %% LOS signal S_receiver_I_LOS=S_CA_receiver+I_NoisePower*randn(1,N_zong); S_receiver_Q_LOS=sqrt(Q_NoisePower)*randn(1,N_zong); fft_sig = fft((S_receiver_I_LOS + 1i*S_receiver_Q_LOS)); L_res = round(BW/f_sample/2*N_zong); fft_sig(L_res+1:end-L_res) = 0; sigBandL = ifft(fft_sig); RecSigI_LOS = real(sigBandL); RecSigQ_LOS = imag(sigBandL); %% multipath signal S_receiver_I_multipath=MDR*S_CA_receiver_multipath+I_NoisePower*randn(1,N_zong); S_receiver_Q_multipath=sqrt(Q_NoisePower)*randn(1,N_zong); fft_sig = fft((S_receiver_I_multipath + 1i*S_receiver_Q_multipath)); L_res = round(BW/f_sample/2*N_zong); fft_sig(L_res+1:end-L_res) = 0; sigBandL = ifft(fft_sig); RecSigI_multipath = real(sigBandL); RecSigQ_multipath = imag(sigBandL); %% IE=sum(RecSigI_multipath_added.*s_E)/N_zong;QE=sum(RecSigQ_multipath_added.*s_E)/N_zong; % IE_up=sum(RecSigI_up.*s_E)/N_zong;QE_up=sum(RecSigQ_up.*s_E)/N_zong; IP_multipath_added=sum(RecSigI_multipath_added.*s_P)/N_zong;QP_multipath_added=sum(RecSigQ_multipath_added.*s_P)/N_zong; IP_multipath=sum(RecSigI_multipath.*s_P)/N_zong;QP_multipath=sum(RecSigQ_multipath.*s_P)/N_zong; IP_LOS=sum(RecSigI_LOS.*s_P)/N_zong;QP_LOS=sum(RecSigQ_LOS.*s_P)/N_zong; % IP_up=sum(RecSigI_up.*s_P)/N_zong;QP_up=sum(RecSigQ_up.*s_P)/N_zong; IL=sum(RecSigI_multipath_added.*s_L)/N_zong;QL=sum(RecSigQ_multipath_added.*s_L)/N_zong; % IL_up=sum(RecSigI_up.*s_L)/N_zong;QL_up=sum(RecSigQ_up.*s_L)/N_zong; %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% R_BPSK_like_multipath_added(k)=sqrt(IP_multipath_added^2+QP_multipath_added^2);% R_BPSK_like_multipath(k)=sqrt(IP_multipath^2+QP_multipath^2); R_BPSK_like_LOS(k)=sqrt(IP_LOS^2+QP_LOS^2); Discriminator_out(k)=((IE^2+QE^2)-(IL^2+QL^2))/( (IE^2+QE^2)+(IL^2+QL^2) ); temp_string=['Running ' num2str(ceil(k/N_tao*10000)/100) '%']; waitbar(k/N_tao,h_wait,temp_string); end close(h_wait); %% figure; plot(tao/Tc,R_BPSK_like_multipath_added,'LineWidth',2);grid on; hold on;plot(tao/Tc,R_BPSK_like_multipath,'LineWidth',2);grid on; hold on;plot(tao/Tc,R_BPSK_like_LOS,'LineWidth',2);grid on; legend('multipath added signal','multipath signal','LOS signal'); % figure; % plot(tao/Tc,Discriminator_out);grid on; % saveas(gcf,'DIS_BPSK.fig');