Free Space Path Loss Calculator

Free Space Path Loss

Calculate the attenuation of a radio signal as it propagates through free space.

Path Loss (FSPL)
100.05
decibels (dB)

The Formula

FSPL (dB) = 20 log₁₀(d) + 20 log₁₀(f) + 92.45

Where d is distance in km and f is frequency in GHz. This formula assumes isotropic antennas and a clear line of sight.

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