Work out the access point spacing and cell overlap that lets devices roam without dropping the connection.
Roaming needs adjacent cells to overlap so a client can associate with the next access point before losing the current one. Spacing cells at twice the radius less the overlap fraction gives the layout, and dividing floor area by the effective cell area gives the count. Too little overlap causes dropped calls as users walk between rooms; too much causes co-channel interference and clients that cling to a distant access point.
WiFi Roaming
Spacing = 2 × cell radius × (1 − overlap); access points = area ÷ effective cell area
Spacing = 2 × cell radius × (1 − overlap); access points = area ÷ effective cell area Roaming needs adjacent cells to overlap so a client can associate with the next access point before losing the current one. Spacing cells at twice the radius less the overlap fraction gives the layout, and dividing floor area by the effective cell area gives the count.
Too little overlap causes dropped calls as users walk between rooms; too much causes co-channel interference and clients that cling to a distant access point.
This calculator takes 4 inputs: Usable cell radius per access point, Designed cell overlap, Area to cover, Client roaming threshold. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.