The folks at Novarum, who include two of the pioneers of Wi-Fi, offer a free report on outdoor Wi-Fi network building: The recommendations aren't surprising to anyone who has followed this site. Novarum recommends a whopping 60 access points per square mile to exceed 90 percent coverage for 802.11n laptops at rates higher than expected 4G cellular network speeds.
That's a high bar, but Novarum has tested existing networks, and it's not far off from what's been documented in the field. There's a joke in the report in the form of a headline on page 5 that reads, "60 is the new 20." Way back in 2004/2005, metro-scale Wi-Fi companies were saying good coverage could be achieved with as few as 20 nodes, which proved laughably low.
Older 802.11g network hardware can't deliver, the company says, with 80 percent coverage provided for laptops and 50 percent for smartphones. However, Novarum also says smartphones might see just 50 to 75 percent coverage for smartphones from high-quality 802.11n network.
The company recommends that 802.11n be used in both 2.4 and 5 GHz bands, and that 802.11b be avoided on clients.
This report is based on 175 network analyses in 36 cities over a 3 1/2 year period.