Is your team the winner of the first Future City Challenge competition? Together IBM, Digita and Etteplan are organizing the first nationwide competition in Finland to design innovative solutions and applications that make everyday life in cities easier. The competition is aimed at companies, start-ups and students interested in resolving city challenges.
Join us in developing the city of the future!
We help the teams with LoRaWAN questions!
Digita provides participants access to Digita’s IoT network that is based on the nationwide LoRaWAN technology.
Below we have gathered the most common questions and answers of LoRaWAN technology:
What is Digita LoRaWAN network coverage?
You can find coverage maps here: http://digitaiot.navici.com/
Please note that if you are indoors, the coverage also depends on local conditions on site (type of building etc).
What is ADR?
ADR stands for Adaptative Data Rate and it’s one of the great features of LoRa technology. It enables low battery consumption devices to communicate over long distances. In short, the ADR is a trade-off between battery consumption and sensitivity.
The amount of time used by a device for sending a packet depends mostly on the data rate used. With the highest data rate (DR5) the battery consumption is minimized so is the sensitivity. And with the lowest data rate (DR0) the battery consumption is higher but the sensitivity is optimal which means that the device will be able to reach the network further away.
In Digita we even managed to get packets sent from Tallinn to Helsinki using DR0. That’s a distance of more than 80km.
How does the ADR mechanism work?
Most of the time, a LoRaWAN end-device will change its data rate when required by the network. Digita’s core network holds the logic which computes the optimal data rate for the end-device. The data rate calculation is based on the radio frequency (RF) parameters of packets received by the network. The data rate calculation is based on several samples to prevent the end-device from constantly switching its data rate. When the network decides that the end-device should change its data rate, it sends a downlink (DL) LoRaWAN command to the end-device.
There is also a “standalone” LoRaWAN mechanism which lowers end-device’s data rate independantly of the network. This is a slow mechanism which kicks in when an end-device attached to the network hasn’t receviced a DL for a while. Typically, it happens when an end-device has been moved from a place with a very good signal (e.g. near a gateway) to a place with a lesser signal strength and quality. By lowering its data rate the device increases its reach and capability to receive a DL from the network.
ADR is a powerful mechanism meant for fixed LoRaWAN end-devices. For mobile devices (e.g. trackers), a fixed data rate is the good practice (e.g. DR2)
Have you heard of Digita’s pilot where we are tracking reindeers? Well, that’s a typical case when we use a fixed data rate.
If your question is not on the list, please send a new one to: IoT_Services@digita.fi
We update the Q&A list continuously during the competition.