θ = 1 0 ∘ = 0.1745 rad
L = 20 lo g 10 ( D d )
The signal strength decreases by 20 dB over a distance of 10 km, so the distance between the transmitter and receiver is: exercice corrige faisceaux hertziens pdf
D = 20 K m ∗ 14 4.2 = 6 K m
θ = D 2.44 λ
λ = 3 cm = 0.03 m
Faisceaux Hertziens are directional beams of electromagnetic radiation, typically in the radio frequency range, that are used for wireless communication. They are designed to propagate through free space, such as air or vacuum, and are used to transmit information over long distances. θ = 1 0 ∘ = 0