The Model
Log-distance path loss model is formally expressed as:
where
- is the total path loss measured in Decibel (dB)
- is the transmitted power in dBm, where
- is the transmitted power in watt.
- is the received power in dBm, where
- is the received power in watt.
- is the path loss at the reference distance d0. Unit: Decibel (dB)
- is the length of the path.
- is the reference distance, usually 1 km (or 1 mile).
- is the path loss exponent.
- is a normal (or Gaussian) random variable with zero mean, reflecting the attenuation (in decibel) caused by flat fading. In case of no fading, this variable is 0. In case of only shadow fading or slow fading, this random variable may have Gaussian distribution with standard deviation in dB, resulting in log-normal distribution of the received power in Watt. In case of only fast fading caused by multipath propagation, the corresponding gain in Watts may be modelled as a random variable with Rayleigh distribution or Ricean distribution.
Read more about this topic: Log-distance Path Loss Model, Mathematical Formulation
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