%ofdm data symbol var parameters
function ofdm_data_parm_var = update_ofdm_data_parm_var

    global ofdm_data_parm_const;
    global ofdm_data_parm_var;
    
    %Set ofdm_data_parm_var==========================================    
    if ofdm_data_parm_const.UsePilot
        %Set the index
        index = rem(ofdm_data_parm_var.Index, size(ofdm_data_parm_const.PilotSubcSymbol, 1));
        index = index + 1;
        ofdm_data_parm_var.Index = index;
        %Number of pilot in each ofdm symbol 
        ofdm_data_parm_var.NumPilotSubc = ofdm_data_parm_const.PilotScramble(index);
        %If the ofdm symbol have pilot
        ofdm_data_parm_var.HavePilot = (ofdm_data_parm_var.NumPilotSubc > 0);
        %Ofdm symbol's pilot index
        ofdm_data_parm_var.PilotSubcIdx = ofdm_data_parm_const.PilotSubcPatt(index, :);
        %Pilot symbol in ach ofdm symbol 
        ofdm_data_parm_var.PilotSymbol = ofdm_data_parm_const.PilotSubcSymbol(index, :);
        %Number of data in each ofdm symbol 
        ofdm_data_parm_var.NumDataSubc = ofdm_data_parm_const.UsedNumSubc - ofdm_data_parm_var.NumPilotSubc;
        %Ofdm symbol's data index
        ofdm_data_parm_var.DataSubcIdx = setdiff(ofdm_data_parm_const.UsedSubcIdx, ofdm_data_parm_var.PilotSubcIdx);
        %Transmit power
        ofdm_data_parm_var.TransmitPower = ones(1, ofdm_data_parm_var.NumDataSubc);
        %Calculate how much bits in each ofdm symbol
        mod_type = ofdm_data_parm_const.Modulation + 1;
        ofdm_data_parm_var.NumBits = ofdm_data_parm_const.ModulationBits(mod_type) * ofdm_data_parm_var.NumDataSubc;    
    end
end