09 Aug LoRaWAN GeoLocation
What is LoRa Geolocation
For those who don’t know, LoRa® Geolocation is a new way to locate devices in rural and urban areas based on the LoRa platform. The traditional way to track a device location (moving or static) is to install a GPS sensor within the device. This is a common solution for 3G/4G GPRS trackers. However, for LPWAN solutions, GPS isn’t a good fit. LPWAN solutions by design are low-power, and long battery life (up to 10 years). However, GPS sensors are power-hungry and can reduce the battery life of an LPWAN sensor by a factor or 40-50.
LoRa GeoLocation is a conceptual but practical solution to track LPWAN sensors, specifically LoRa sensors without GPS.
How does LoRa Geolocation Work?
The idea is that when a LoRa signal from a single device is picked up by 3 or more gateways, it’s possible to triangulate the position of the device using timestamps. The SemTech LoRa gateway chips have very accurate clocks that accurately record the time (to within nanoseconds) of when a transmission is received. If you know where the gateways are located, and the exact time they heard from the device, it’s possible to calculate the position.
The functionality is built into all LoRa devices, so this is an out-of-the-box solution that could retrospectively work with any LoRaWAN device. It doesn’t require the LoRa Device to have any specific firmware or code… that’s good news. Any v2.x gateways with the latest Semtech chipsets will support this functionality, and several LoRaWAN networks are working on solutions to triangulate the device position. It’s unfair to describe this as conceptual because they are live trials in progress. However, Semtech, the gateway manufacturers and LoRaWAN networks are still working on the implementation, so it’s not yet possible to describe it as ‘available’/
What’s the accuracy?
Bearing in mind that this is still conceptual, there is room for improvement. Kerlink have suggested that location accuracy of around 100m is possible. Its believed that this could be narrowed down to 50m but there are a number of factors to consider: (1) The number of Gateways in the area, (2) the topology and density of the area, e.g. Urban, (3) the location of the devices within, or under buildings, (4) whether the device is moving or static, and at what speed the device is moving.
With all this in mind, LoRa GeoLocation is never going to offer the same accuracy as GPS. But that doesn’t matter.
Where is GEOLocation Useful?
Asset Inventory: For a lot of assets, you don’t need super-accurate locations. Whether it’s containers, airport assets, cars, delivery drivers or gas canisters, just knowing it’s rough location to within 50 meters is enough.
Static Devices: We’re approached by companies who want to locate static assets. Sound crazy huh? No.. not really. If you a rail operator, and you have 1000’s of pieces of equipment, lighting, machinery, pallets of goods. 95% of the time these will be static. They won’t move or need to be moved. But for the purpose of inventory, to receive regular updates on their locations, ensures you can monitor and maintain an accurate inventory list. You can be alerted to theft more quickly.
Are you interested in GEOLocation?
We’re always excited to discuss new projects and ideas. If you have a requirement for LoRa® Geolocation give us a shout.
Note :LoRa® is a registered trademark of SemTech. The Locate/Navigate/Manage/track image is the copyright of SemTech. Please visit https://www.semtech.com/wireless-rf/lora-geolocation for more information.