ofdm.m

mimoofdm系统自适应功率分配算法

clear all;
close all;
%%%%%%%%%%%%%%%% Display the begin time
fprintf('year:%d ;month:%d ;day: %d; hour:%d ;minute:%d ;seconds: %d ',fix(clock));
fprintf('\n');
A = [1 exp(-1) exp(-2)];        % power delay profile
N = 64;                         % 64 number of symbols in a single OFDM symbol
GI =16;                         % 16 guard interval
Mt = 2;                         % number of Tx antennas
Mr = 2;                         % number of Rx antennas
sig2 = 1e-3;                    % noise variance
M = 8;                          % max constellation bit number
Mgap = 10.^(1:(1.7/10):2.7);    % gap; 间隙
Btot = 1*Mt;;%100*Mt;                  % total bits per OFDM symbol
TransmitIter = 5;%50;              % iterations of symbol transmissions for each channel instance
ChannelIter = 10;%100;              % iterations of independent identically distributed channel instances
GapIter = length(Mgap);

load ENC2.mat
load ENC4.mat
load ENC16.mat
load ENC64.mat
load ENC256.mat

TotEbNo = [];
Errors =[];
EbNo = [];
for lGap = 1:GapIter    %%%% 10
    lGap
    gap = Mgap(lGap);   %%%%%%
    totalErrors = 0;
    for lChan = 1:ChannelIter
        % create channel
        [H h_f]=create_channel(Mt, Mr, A, N+GI);
        % decompose each subchannel in the frequency domain
        %fprintf('year:%d ;month:%d ;day: %d; hour:%d ;minute:%d ;seconds: %d ',fix(clock))
        %fprintf('\n')
        [U S V] = svd_decompose_channel(Mt, Mr, h_f, N);
        %fprintf('year:%d ;month:%d ;day: %d; hour:%d ;minute:%d ;seconds: %d ',fix(clock))
        %fprintf('\n')
        % bitloading
        [bits_alloc,energy_alloc] = BitLoad(S,Btot,Mt*N,gap,sig2,M);
        for lTrans = 1:TransmitIter %%  50
            % bits to transmit
            x = (randn(1,Btot)>0);  %%% 100*Mt
            % modulate
            x_mod = modulate(x,bits_alloc,energy_alloc, s2,s4,s16,s64,s256);
            % precode modulated signal
            x_pre = precode(Mt, x_mod, V, N);
            % ifft, with cyclic prefix for each antenna
            ofdm_symbol =[];
            for i=1:Mt
                ofdm_symbol = [ofdm_symbol; ifft_cp_tx_blk(x_pre(i:Mt:Mt*(N-1)+i),N,GI)];
                %ofdm_symbol = ifft_cp_tx_blk((x_pre((1:Mt):Mt:Mt*(N-1)+(1:Mt))),N,GI);
                %ofdm_symbol =transpose(ofdm_symbol);
            end
            ofdm_symbol2 = reshape(ofdm_symbol,Mt*(N+GI),1);
            % channel
            y = transpose(channel(sig2, Mt, Mr, ofdm_symbol2, H, N+GI));    %%%%%转置
            % fft
            rec_symbol =[];
            for i=1:Mt
                rec_symbol = [rec_symbol; fft_cp_rx_blk(y(i:Mt:Mt*(N+GI-1)+i),N,GI)];
            end
            rec_symbol2 = reshape(rec_symbol,1,Mt*N);
            % shape received signal
            shaped_vals = shape(rec_symbol2, Mr, U, N);
            % demodulate
            y_demod = demodulate(shaped_vals, bits_alloc, energy_alloc, S, s2,s4,s16,s64,s256, c2,c4,c16,c64,c256);
            % comparison
            totalErrors = totalErrors + sum(xor(y_demod,x));
        end
        EbNo = [EbNo sum(energy_alloc)/Btot/sig2];
    end
    Errors = [Errors totalErrors/Btot/ChannelIter/TransmitIter]
    TotEbNo = [TotEbNo mean(EbNo)]
    EbNo = [];
end
%%%%%%%%%%%%%%%% Display the end time; And calculate the calculating_time  
fprintf('year:%d ;month:%d ;day: %d; hour:%d ;minute:%d ;seconds: %d \n',fix(clock))

semilogx(TotEbNo, Errors);
xlabel('Eb/No');
ylabel('BER');
grid on;
if Mt==1 
    if Mr==1 
        save SISO_adaptive2.mat Errors EbNo ;
        title('SISO link, adaptive rate and power');
    else 
        save SIMO_adaptive2.mat Errors EbNo ;
        title('SIMO link, adaptive rate and power');
    end;
else
    if Mr==1 
        save MISO_adaptive2.mat Errors EbNo ;
        title('MISO link, adaptive rate and power');
    else 
        save MIMO_adaptive2.mat Errors EbNo ;
        title('MIMO link, adaptive rate and power');
    end;
end;

display('Program finished!!')