Work out wi fi coverage area instantly with clear inputs, formula shown and shareable results.
Cell radius follows from the link budget — transmit power plus antenna gain minus the target edge signal — applied to a log-distance path loss model where received power falls as 10n log10(distance). The path loss exponent captures the environment: about 2 in open space, 3 in a partitioned office and 4 in industrial space with heavy obstruction.
Log-distance path loss
EIRP = Tx power + antenna gain; budget = EIRP - target RSSI; radius = 10^((budget - reference loss) / (10n)); area = pi r^2
Because path loss rises with the exponent. Doubling distance costs 6 dB in free space but 12 dB at an exponent of 4, so obstructed environments need many more access points.
The uplink. Client devices transmit at much lower power than access points, so a cell edge that looks fine on the AP's signal may fail when the client replies.