I have a MATLAB code that calculates the nFFT points using the expression:
nFFT = 2^(ceil(log2(NRB * 12 / 0.85) + FFT_scaling)),
where NRB = 25 and FFT_scaling = 3.
I would like to understand the purpose of the factor 0.85 in the formula. Additionally, what is the effect of the extra scaling introduced by FFT_scaling? Does it impact the transmission bandwidth of the OFDM signal, or is it simply an oversampling factor?
