hfskfadingcapacity.m

空间无线信道建模程序matlab

% File hFskFadingCapacity
%
% This is a set of scenarios for the Coded Modulation Library.
%
% The simulations specified in this file are for the Shannon capacity
% under modulation constraints.
%
% Last updated on July 4, 2006

% determine where your root directory is
load( 'CmlHome.mat' );

% determine where to store your files
base_name = 'FskCapacity';
if ispc
    data_directory = strcat( cml_home, '\output\', base_name, '\' );
else
    data_directory = strcat( cml_home, '/output/', base_name, '/' );
end
if ~exist( data_directory, 'dir' )
    mkdir(data_directory);
end

few_trials = 10;
many_trials = 200;
epsilon = 1e-4;

% list of values to simulate
% for naming convention, h should be no less than 0.01 apart
% h = 0.01:0.01:1;
% M = [4 8];
M = [2 4 8 16 32 64];
% h=0.45;
h = 1;
% M=2;

% M=4
% h=0.17

minEsNodB = -30;
maxEsNodB = 40;
spacing_coarse = 0.5;
spacing_fine = 0.1;

% What is the minimum BW we are interested in?
min_bandwidth_constraint = 1;

% get the BW information
load BW99percent

% this is the CM capacity in Rayleigh fading
record = 0;
for mcount=1:length(M)
    for hcount=1:length(h)
        record = record + 1;

        sim_param(record).comment = sprintf( 'CM capacity of %d-FSK w/ h=%1.2f in Fading\n', M(mcount), h(hcount) );

        % particular to this record
        sim_param(record).h = h(hcount);
        sim_param(record).mod_order = M(mcount);

        % create the filename and see if it exists
        filename = strcat( 'CM_', int2str( M(mcount) ), 'FSK_h' );

        if ( h(hcount) == 1)
            filename = strcat( filename, '1' );
        elseif (abs(h(hcount)-0.9) < epsilon )
            filename = strcat( filename, '09' );
        elseif (abs(h(hcount)-0.8) < epsilon )
            filename = strcat( filename, '08' );
        elseif (abs(h(hcount)-0.7) < epsilon )
            filename = strcat( filename, '07' );
        elseif (abs(h(hcount)-0.6) < epsilon )
            filename = strcat( filename, '06' );
        elseif (abs(h(hcount)-0.5) < epsilon )
            filename = strcat( filename, '05' );
        elseif (abs(h(hcount)-0.4) < epsilon )
            filename = strcat( filename, '04' );
        elseif (abs(h(hcount)-0.3) < epsilon )
            filename = strcat( filename, '03' );
        elseif (abs(h(hcount)-0.2) < epsilon )
            filename = strcat( filename, '02' );
        elseif (abs(h(hcount)-0.1) < epsilon )
            filename = strcat( filename, '01' );
        elseif ( h(hcount) < 0.1 )
            filename = strcat( filename, '00', int2str( 100*h(hcount) ) );
        else
            filename = strcat( filename, '0', int2str( 100*h(hcount) ) );
        end

        filename = strcat( filename, '_Rayleigh_CSI.mat' );

                % see if the file already exists
        sim_param(record).filename = strcat( data_directory, filename );
        fprintf( strcat ( 'Attempting to open file ', filename, '\n' ));
        fid = fopen( sim_param(record).filename );
        if (  fid > 0 )
            fprintf( 'File exists\n\n' );

            % load
            load(sim_param(record).filename);
            fclose( fid );          

            % determine the interesting range of SNR
            r = save_state.capacity_avg;
            rindex = find( r>epsilon & r< 1-epsilon);

            if (length(rindex)==0)
                fprintf( 'rindex is empty\n' );
                % create SNR
                sim_param(record).SNR = minEsNodB:spacing_coarse:maxEsNodB;
                sim_param(record).max_trials = few_trials*ones( 1, length( sim_param(record).SNR ) );
            else

                % first determine min EsNo (for unconstrained bandwidth)
                EsNo = 10.^(save_param.SNR(rindex)/10);
                EbNo = EsNo./(r(rindex)*log2(save_param.mod_order));

                [y,index] = min(EbNo);
                ThisMinEsNodB = 10*log10(EsNo(index));

                % then determine max EsNo (for constrained bandwidth)

                % determine the minimum allowable code rate
                M_values = find( BwMatrix(:,1) == save_param.mod_order );
                h_values = find( abs(BwMatrix(:,2) - save_param.h) < epsilon);
                Matching_row = min( intersect( M_values, h_values ) );
                bandwidth = BwMatrix( Matching_row, 3 );

                min_rate = bandwidth/log2(save_param.mod_order)/min_bandwidth_constraint;

                ThisMaxEsNodB = NaN;
                if (length(rindex) > 1 )
                    ThisMaxEsNodB = interp1( r(rindex), save_param.SNR(rindex), min_rate );
                end

                if ( isnan( ThisMaxEsNodB ) )
                    ThisMaxEsNodB = maxEsNodB;
                end

                fprintf( 'h=%1.2f min=%2.1f max=%2.1f\n', save_param.h, ThisMinEsNodB, ThisMaxEsNodB );
                fprintf( '\n' );

                coarse_spacings = (maxEsNodB-minEsNodB)/spacing_coarse + 1;
                fine_spacings = spacing_coarse/spacing_fine;                
                
                % create SNR vector
                EsNodB = minEsNodB;
                index = 1;
                for i=1:coarse_spacings                    
                    for j=1:fine_spacings
                        fine = (EsNodB >= ThisMinEsNodB - spacing_coarse )&(EsNodB <= ThisMaxEsNodB + spacing_coarse);
                        if (j==1)
                            sim_param(record).SNR(index) = EsNodB;
                            if ( fine )
                                sim_param(record).max_trials(index) = many_trials;
                            else
                                sim_param(record).max_trials(index) = few_trials;                            
                            end
                            index = index + 1;
                        elseif ( ( fine | sum( abs( save_param.SNR-EsNodB ) < epsilon ) )&(i<coarse_spacings) ) 
                            sim_param(record).SNR(index) = EsNodB;
                            sim_param(record).max_trials(index) = many_trials;
                            index = index + 1;
                        end                        
                        
                        EsNodB = EsNodB + spacing_fine;                        
                    end
                end
            end

        else
            % fprintf( 'File does not exist\n\n' );
            % create SNR
            sim_param(record).SNR = minEsNodB:spacing_coarse:maxEsNodB;
            sim_param(record).max_trials = few_trials*ones( 1, length( sim_param(record).SNR ) );
        end

        % generic to all records
        sim_param(record).sim_type = 'capacity';
        sim_param(record).SNR_type = 'Es/No in dB';
        sim_param(record).framesize = 10000;
        sim_param(record).modulation = 'FSK';
        sim_param(record).channel = 'Rayleigh';
        sim_param(record).csi_flag = 1; %noncoherent
        sim_param(record).bicm = 0;
        sim_param(record).demod_type = 0; % does not matter if not BICM
        sim_param(record).linetype = 'r:';
        sim_param(record).legend = sim_param(record).comment;
        sim_param(record).reset = 0;
        sim_param(record).save_rate = 50;
        sim_param(record).mapping = 'gray';
    end
end