sum of large scale daing and small scale fading

I have my measured signal in dBm units. My signal is the superpositiopn of large scale fadin and small scale fading. I know that the large scale fading is equal to the averadged power. I would like to separate them. Which on of this codes is correct:

    smallScaleFading_dBm=MeasuredPower_dBm - MeanPower_dBm; % subtruct in dBm units than convert to linear units
    smallScaleFading_linear=10.^((smallScaleFading_dBm-30)/20);
    
    %%%% code 2 %%%%
    MeasuredPower_linear=10.^((MeasuredPower_dBm-30)/20); % convert in linear units than subtruct
    MeanPower_linear=10.^((MeanPower_dBm-30)/20);
    smallScaleFading_linear=MeasuredPower_linear - MeanPower_linear;