The Arduino platform is well suited to building sensor networks, being low-power, low-cost, and beginner-friendly. For home or office use, there are plenty of connectivity options: Ethernet or Wi-Fi is easily added to an Arduino, as is Bluetooth; alternatively, short-range radio networks can be quickly assembled using unlicensed networks.
What do you do when your sensors are out in the field, though? A common solution is to use GSM connectivity - the data side of a mobile phone network, basically - but this comes with ongoing costs. Our friend Andrew Back is currently working on an alternative for his corner of the UK Maker Belt: a LoRaWAN network.
Named for its status as a low-power radio-based wide-area network, LoRaWan is designed specifically for long-range yet low-power devices. Its most well-known implementation is in The Things Network, and it's this network that Andrew seeks to expand by adding a Calderdale branch. Using a single homebrew LoRaWAN base-station running on the licence-free 868MHz radio spectrum, Andrew has been able to cover an estimated 15KM of the Calder valley with connectivity - and at a power draw of under 7W.
With the installation nearly completed, Andrew is shortly to move onto testing. Should it prove successful, the LoRaWAN network will be used to provide connectivity to a number of flood sensors built as part of the crowd-sourced Flood Network we discussed last year. The network itself, though, is device-agnostic: any LoRaWAN node, including Arduinos fitted with suitable radio hardware, could communicate using the same network - and without paying any subscription or data usage fees.
A great feature of LoRaWAN is that anyone can set up a gateway and there are solutions available from numerous different manufacturers. So you don't have to wait for the network to come to you — you can build the network yourself. Something that the originators of The Things Network in Amsterdam used to their advantage, crowdsourcing a complete city-wide network in only 6 weeks and achieving this with just 10 gateways.