According to ITU-R Rec. P.452-5 the median path loss between transmitter and receiver is given by the following equation:
(Eq. 216)
where:
Lbd(p) is the basic loss in dB as function of the time percentage in %
f is the frequency in GHz
d is the distance in km
Ld(p) is the diffraction loss in dB as function of the time percentage in %
Ag is the attenuation due to atmospheric gas and water in dB