mimo.rar_MIMO信道_mimo_mimo 多径_多径 MIMO_多径MIMO

clear all; %main %general parameters Tx=2; % the number of transmit antennas Rx=2; % the number of receive anntennas NumberOfSubfreq=512; % the number of sub_carrier wave in OFDM subsystem NumberOfBurst=100; % the number of bursts NumberOfSymbols=10; % the number of ofdm symbols per burst NumberOfbits=952; % the number of bits per ofdm symbol. NumberOfbits=(NumberOfSubfreq-2*number_of_pilot)*Tx*modulate_type*1/2 % channel parameters pathnumber=1; % the number of multipath jakes_fd =100; % Hz jakes_fs = 5000000; % Hz in_number= NumberOfSymbols*NumberOfBurst*(512+128); disp('please select modulate type: 1 BPSK; 2 QPSK; 3 8PSK; 4 16QAM') %modulate_type=input('modulate type=:'); % 1 BPSK 2 QPSK 3 8PSK 4 16QAM modulate_type=2; begin=-8; step=2; for s=1:8 % loop of iteration SNR(s)=begin+(s-1)*step; %generate SNR No = power(10,-SNR(s)/10)/modulate_type; %calculate No sigma=sqrt(No/2); % loop of each burst for Number_Of_burst=1:NumberOfBurst % generate original_bit rand('state',0); original_bit=round(rand(NumberOfSymbols,NumberOfbits));% dimension NumberOfSymbols*NumberOfbits=10*952; about 10k bits % loop of each ofdm symbol for NumberOfLoops=1:NumberOfSymbols %-------------------------transmit part ---------------------------------------% input_bits=original_bit(NumberOfLoops,:);% dimension 1*952 %modulate temp_modulate_symbol=modulate(modulate_type,input_bits,NumberOfbits);%dimension 1*476 %transmit power normal modulate_symbol=temp_modulate_symbol./sqrt(Tx); % dimension 1*476 %serial to paralle length_of_column=NumberOfbits/(Tx*modulate_type);% 238 vector=reshape(modulate_symbol,Tx,length_of_column); % dimension 2*238 % MIMO Alamouti coding for k=1:length_of_column X=vector(:,k); % dimension 2*1 Alamouti_coding=Alamouti(X); % dimension 2*2 MIMO_coding(:,(2*k-1):(2*k))=Alamouti_coding; % dimension 2*476 end %end of Alamouti coding tx1_symbol=MIMO_coding(1,:);% the transmited data of tx1 dimension 1*476 tx2_symbol=MIMO_coding(2,:);% the transmited data of tx2 dimension 1*476 %insert pilot [ofdm_input_tx1,ofdm_input_tx2]=add_pilot_fast_fading(tx1_symbol,tx2_symbol);% dimension 1*512 %OFDM guard_interval=128; output_ofdm_tx1=ifft_cp_tx_blk(ofdm_input_tx1,NumberOfSubfreq,guard_interval);% dimension 1*(512+128) output_ofdm_tx2=ifft_cp_tx_blk(ofdm_input_tx2,NumberOfSubfreq,guard_interval);% dimension 1*(512+128) %-------------------- end of transmit part--------------------------------------------------------% %-------------------- Start of channel part--------------------------------------------------------% % read channel weighs rayleigh_I=load('D:\MIMO\MIMO+OFDM\all\rayleigh_I.txt'); rayleigh_Q=load('D:\MIMO\MIMO+OFDM\all\rayleigh_Q.txt'); position=Number_Of_burst*NumberOfLoops; % extrat data of n_th ofdm symbol rayleigh=rayleigh_I(2560*position-2559:2560*position)+1i*rayleigh_Q(2560*position-2559:2560*position); for i=1:640 H(1,1,i)=rayleigh(i); H(1,2,i)=rayleigh(i+640); H(2,1,i)=rayleigh(i+1280); H(2,2,i)=rayleigh(i+1920); end %input channel for i=1:640 X=[output_ofdm_tx1(i);output_ofdm_tx2(i)]; h=H(:,:,i); y=h*X; channel_output(:,i)=y; end %add AWGN noise noise=randn(2,640)*sigma/sqrt(NumberOfSubfreq); %生成高斯白噪声 %received data rx1=channel_output(1,:)+noise(1,:);% 维数 1×(512+128) rx2=channel_output(2,:)+noise(2,:);% 维数 1×(512+128) %-------------------- end of channel part--------------------------------------------------------% %------------------ receive part---------------------------------------------------------------% % OFDM demodulate ofdm_demodulate_rx1=fft_cp_rx_blk(rx1,NumberOfSubfreq,guard_interval);% dimension 1*512 ofdm_demodulate_rx2=fft_cp_rx_blk(rx2,NumberOfSubfreq,guard_interval);% dimension 1*512 % channel estimat [H_est,rx1_symbols,rx2_symbols]=est_fast_fading(ofdm_demodulate_rx1,ofdm_demodulate_rx2);% rx1_symbols dimension 1*476, H_est dimension 2*952 % MIMO decoding for i=1:length_of_column H_MIMO=( H_est(:,4*i-3:4*i-2)+H_est(:,4*i-1:4*i))/2; % H dimension 2*2 receiver_symbol(1,:)=rx1_symbols( (2*i-1) : 2*i);% dimension 1*2 receiver_symbol(2,:)=rx2_symbols( (2*i-1) : 2*i);% dimension 1*2 receiver_symbol的dimension 2*2 output_decoding=DeAlamouti(H_MIMO,receiver_symbol,Rx); % dimension 1*2 MIMO_decoding((2*i-1) : 2*i,1)=output_decoding; % dimension 476*1; end %end of MIMO decoding % demodulate [NumberOfRows,NumberOfcolumns]=size(MIMO_decoding); temp_receive_bits=demodulate(MIMO_decoding,modulate_type,NumberOfRows);% dimension2*476; receive_bit(NumberOfLoops,:)=reshape(temp_receive_bits,1,NumberOfbits);% dimension NumberOfSymbols*952 end % end of 每个帧的循环 % calculated the number of error bits per burst compare_matrix=(receive_bit ~= original_bit); error_bits(Number_Of_burst)=sum(sum(compare_matrix,2)); end % end of 每个迭代的主循环,即若干帧的循环 % calculate BER total_error_bits=sum(error_bits); total_bits=NumberOfBurst*NumberOfSymbols*NumberOfbits; BER(s)=total_error_bits/total_bits; end % end of 每个仿真点的主循环 % drwa figure draw_figure(SNR,BER,modulate_type,Rx,Tx);