matlab纤无线通信系统的仿真，用的是4QAM调制，LS信道估计，还包括Optisystem的仿真，非常珍贵.rar

RF_signal = InputPort1.Sampled.Signal; %将Optisystem输入数据采样序列赋值到RF_signal变量 RF_length=length(RF_signal_sin); OutputPort1=InputPort1; Bitrate =Parameter0;%2.5GHz Q =Parameter1;% 采样比特=64 global pilot_signal; global data_after; Tu=length(binary)/Bitrate; fc=Bitrate; Rs=Q*Bitrate; t=1/Rs:1/Rs:Tu; size_fft=256; % 进行FFT/IFFT的长度=64 r_tilde=exp(-1i*2*pi*fc.*t).*RF_signal; %将序列乘以一个频率为fc的信号 [B,AA] = butter(13,3/4); r_info=2*filter(B,AA,r_tilde); %通过带通滤波器，进行中频解调 data_r = r_info(1:2*Q:length(r_info));%进行间隔为2*Q的抽样， 与调制匹配 data_r1 = data_r(65:320);%去循环前缀保护间隔 data_r2 =fft(data_r1,size_fft)/size_fft;%FFT调制，进行OFDM解调 f_data =data_r2(1:8:256);%取出传输后的导频信号 H = f_data./pilot_signal;%求出信道 H_1 = ifft(H,32); H_r =fft([H_1(1:16),zeros(1,224),H_1(17:32)],size_fft);%将信道变成信号的长度 data_r3 =data_r2./H_r;%进行信道估计，相位均衡 figure(1) plot(real(data_r2),imag(data_r2),'r*');%输出均衡前的QAM输出 figure(2) plot(real(data_r3),imag(data_r3),'k.');%输出均衡后的QAM输出 data_out1 = [data_r3,data_after]; data_out=de_QAM_code4(data_out1);%4QAM 1.25GHz for i=1:length(data_out) binary_out((Q*(i-1)+1):Q*i)=data_out(i);%将数字比特变成模拟信号 end OutputPort1 = InputPort1; for i=1:RF_length OutputPort1.Sampled.Signal(i) =binary_out(i);%输出到optisystem end