gen_sourcebits.m

国外大学的同志作出来的好程序

function info_bits=gen_sourcebits(sim);
%Acorrding to sim,
%generate certain numbers of random bits
%
%
Nd=sim.frame_data_len;
if sim.tx_num==1,
    total_symbols = round((Nd * sim.frame_num));
elseif sim.tx_num>1
    total_symbols = round((Nd * sim.frame_num)*sim.stc_rate);
end

%there are tailing bits in trellis coding (convolutional coding).
%and zero-padding for puctured codes. So, sim.coding_reg_num is just a
%margin number.
total_bits=floor((total_symbols * sim.mapping_rate-(sim.coding_reg_num*sim.mapping_rate))*sim.coding_rate);

if total_bits<0,
    disp('[gen_sourcebits]Error: the number of source bits is minus.');
    info_bits=[];
    return;
elseif total_bits==0,
    disp('[gen_sourcebits]Warning: the number of source bits is zero.');
end
%random info_bitsrmation bits.
info_bits=(rand(total_bits,1)>0.5);