As others mentioned, this is using LoRaWAN radios, which are typically stated as having a range of around ten miles. Here is a group that's trying to build up a worldwide LoRa network that's free and open: <a href="https://thethingsnetwork.org/" rel="nofollow">https://thethingsnetwork.org/</a>
They have a datasheet [0] for an "Environmental Monitoring Sensor" which lists a line-of-sight range of 50 miles and 1–3 miles in urban settings. For comparison, Digi's XBee PRO ZigBee wireless modules have a line-of-sight range of 2 miles [1]. I'm a little bit skeptical about the 50 mile range claim (seems too good to be true), but this is an interesting product nonetheless.<p>[0]: <a href="http://www.beepnetworks.com/img/datasheet.pdf" rel="nofollow">http://www.beepnetworks.com/img/datasheet.pdf</a><p>[1]: <a href="http://www.digi.com/products/xbee-rf-solutions/rf-modules/xbee-zigbee#specifications" rel="nofollow">http://www.digi.com/products/xbee-rf-solutions/rf-modules/xb...</a>
These are transmitters and the signals they send out have to be received somewhere. Where are the receivers, how much do they cost, and where would one get started building out the "receiving side" of one of these networks?
The range of operating temperature is undefined in the datasheet. Would that work outdoors in winter or in direct sunlight? Think Alaska or the tropics. Humidity is pretty important too.