1132146548_DCO-OFDM_可见光通信_dcoofdm_通信系统仿真_matlab

clc; clear all ; close all; global N_sc; N_sc=256;%有效数据的子载波数 BitperSymbol=4; %每符号的比特数 DataSymlength=22; %传输的符号数 512 Data_Bitlength=DataSymlength*N_sc*BitperSymbol; %% 产生数据信号 ------------(X_Data) Y_BitSource=round(rand(1,DataSymlength*BitperSymbol*N_sc)); s ysym=bi2de(reshape(Y_BitSource',BitperSymbol,length(Y_BitSource)/BitperSymbol).','left-msb'); % 十进制数 graycode=[0 1 3 2 4 5 7 6 12 13 15 14 8 9 11 10]; %格雷码编码规则 nsg=graycode(ysym+1); %将随机数映射成格雷码 %% ------------------------------------------串并变换-----ysym--------------------------- Y_input=reshape(nsg,N_sc/4,[]); %% -----------------------------------------MQMAM调制------------------------- hI = modem.qammod(2^BitperSymbol); hII = modem.qamdemod(2^BitperSymbol); Y_Data = modulate(hI,Y_input); % 复数 % figure (1) % plot(Y_Data,'*r'); %画接收信号的星座图 % axis([-4, 4, -4, 4]); % grid on %% 自共轭 %% Hermitian对称 %% -----------------------------------DCO信号调整--------------------------------------- NumLoop=length(Y_Data(1,:)); SymIFFT_Y = zeros(130,NumLoop); SymIFFTtmptmp_Y = zeros(130,NumLoop); SymIFFTtmp_Y = reshape(Y_Data,64,NumLoop); SymIFFTtmptmp_Y(1,:) = SymIFFT_Y(1,:); % 实数 SymIFFTtmptmp_Y(2:65,:) = SymIFFTtmp_Y; % 实数 SymIFFTtmptmp_Y(66,:)=SymIFFT_Y(66,:); SymIFFTtmptmp_Y(65+1,:) = SymIFFT_Y(65+1,:); SymIFFTtmptmp_Y(65+2:65*2,:) = flipdim(conj(SymIFFTtmptmp_Y(2:65,:)),1); %% ---------------------------------------------ifft变换------------------------- Y1_ifft_output=ifft(SymIFFTtmptmp_Y); %% ---------------------------------------------DCO偏置-------------------------- Y1_ifft_output_D=std2(Y1_ifft_output); U=2.15;%偏置系数 % U=1.9;%偏置系数 Din_y=U*sqrt(Y1_ifft_output_D); Din=Din_y*ones(130,NumLoop); Y1_ifft_output_y=Y1_ifft_output+Din; Y1_ifft_output_y(find(Y1_ifft_output_y<0))=0; si=1; s1=zeros(1,snr_shu+1); s2=zeros(1,snr_shu+1); %% ---------------------------------------------------------------------------信道---------------------------------------- for snr = 0:1:snr_shu; for num = 100; % snr=10; ofdm_sig_y=awgn(Y1_ifft_output_y, snr,'measured' ); %% ----------------------------------------------DCO去偏置------------------------------------- ofdm_sig_y_1=ofdm_sig_y-Din; %% --------------------------------------------FFT运算------------------------------------- RY1_QAMSymbol=fft(ofdm_sig_y_1); %% ---------------------------------反Hermitian对称---------------------- %% DCO SymEqtmp1_y=zeros(64,NumLoop); SymEqtmp1_y_1= RY1_QAMSymbol(2:65,:); %% ---------MQAM解调------------ %% DCO DY1_int = demodulate(hII,SymEqtmp1_y_1); nsg1=graycode(DY1_int+1); % nsg1_1=reshape(nsg1,[],1); DY1_Bit = de2bi(nsg1,'left-msb'); nsg2=graycode(y_2+1); DY1_Bit_1 = de2bi(nsg2,'left-msb'); %% 并串变换 DY1_Bit_chuan=reshape(DY1_Bit',1,[]); DY1_Bit_chuan_1=reshape(DY1_Bit_1',1,[]); %% BER计算 %% DCO L1=length(DY1_Bit_chuan_1); L2=length(Y_BitSource); % Y_input_ceshi=Y_BitSource(L2-L1+1:L2); % DY1_Bit_ceshi=DY1_Bit_chuan(L2-L1+1:L2); Y_input_ceshi=Y_BitSource; DY1_Bit_ceshi=DY1_Bit_chuan; % [number_of_errors_y,bit_error_rate_y]=biterr(DY1_Bit_chuan_3,DY1_Bit_ceshi); [number_of_errors_y,bit_error_rate_y]=biterr(Y_input_ceshi,DY1_Bit_ceshi); xlbf=DY1_Bit_chuan(1:L2-L1); DY1_Bit_ceshi_1=[xlbf DY1_Bit_chuan_1]; % DY1_Bit_ceshi_1=DY1_Bit_chuan_1; [number_of_errors_y_1,bit_error_rate_y_1]=biterr(Y_input_ceshi,DY1_Bit_ceshi_1);