propagation model using neural network (I am beginner)
I believe you need a data for the response (PL) and data for the independent variables in order to find n.
you can find n using that data in SPSS, excel, Matlab etc.
Good luck.
Propagation model: 
P = 10 * n * log10 (d/do)
P = path loss (dB)
n = the path loss distance exponent
d = distance (m)
do = reference distance (m)
The initial idea is to make the loss measurements 'P' with respect to a distance 'd', and to determine the value of 'n'
my question: is this implementation possible using multi-layer Perceptron?
But what could be my inputs and outputs? I thought of something like:
input: distance 'd'
output: Loss "P"
But I could not think of a solution to determine 'n' from these parameters
the idea is that it is something simple, only for study and later improved