# Middle-Zone Model
## Equation
$P_L(d)=\left(\frac{4\pi f_cd}{c}\right)^2(F(d))^{k_1}(W(d))^{k_2}R(d)$
### Parameters
- F(d) and W(d) are floor and wall attenuation[^1]
- R(d) = reflection loss
- $k_1$ and $k_2$ are the number of floors and walls
- W(d) depends on the material of the wall [^2]
# References
1. [TELE4652-lecture-03](../../03%20-%20University/TELE4652/Lectures/TELE4652-lecture-03.pdf)
# Footnotes
[^1]: F(d) = 20-40dB
[^2]: Wood (15mm) = 2.5-3.5dB
Concrete block is 8-15dB