- what is ADR 3?
- I see a few new Connectivity plans in the devicemanager, what are these for? What are the costs?
- do existing RN2483 devices support ADR 3 (e.g. 1.0.3 and 1.0.4)?
- do existing Semtech/STM LoRa stacks support ADR 3?
- If not: will this requirement break communication for non-compliant nodes?
Beste antwoord door Tim B
ADR v3 is the abbreviation of Adaptive Data Rate version 3 and is the replacement of the older version 2. It’s not a specific LoRa Alliance feature, but an update in our network that changes the way our algorithm for data rate adjustment works. In the previous data rate adaption algorithm, the network would adjust the data rate, based on just antenna diversity settings (how many gateways are receiving the message), in the new situation the data rate adjustment will be based more heavily on Packet Error Rate (PER).
With an antenna diversity of 4 (aka ‘optimize the device so that an uplink is always received by 4 gateways), the network would adjust the spreading factor of the device for example directly from 8 to 10 if there was only 1 gateway reached for a number of messages.
In the new algorithm, more heavily based on Packet Error Rate (PER), the network adjusts not only the data rate, but also the NbTrans (Number of Transmissions) of a device. Additionally it will consider the required antenna diversity, which is very important in the Geolocation feature. Following our previous example, the network would check first if setting NbTrans=2 (send the same message twice, over different channels) has the desired effect of reaching the required 4 gateways with at least one of the messages. If it does, it will also verify if it does so over a prolonged period of time, so that it can confirm it will for example not exceed the PER of 10%. If not, it might raise the NbTrans 1 step further or increase the Spreading Factor to 9 and retry this whole step. This new algorithm is more complex and requires a device to handle the NbTrans command and will eventually result in a device that uses less airtime than before, since sending one message on SF10 is more energy consuming than sending two on SF8. Also a lot of our future developments will make use of some mechanics that work in the background of this new release.
Regarding your other questions:
- The new connectivity plans you see are meant for testing purposes, to verify if your device handles the ADR v3 mechanism correctly before we implement it. There are no costs involved for these plans, however, since they are for testing purposes only, they might be available for a limited time only.
- If your devices and the firmware are LoRa Alliance certified and not adjusted afterwards, they should handle ADR v3 correctly.
- We can’t predict how non-certified devices react to this release, since there might be many variations in the firmware. All could behave differently. It is unlikely for a quality device to disconnect due to this change, but it’s better to verify this by checking for certification or testing with the connectivity plan. Certified devices will not have any issues.
- Our Technical Service Description is available for all our customers under ‘Shared Documents’ at the right hand side of the dashboard of the Portal. It might be that you do not have the correct rights to access these documents. The same goes for why you might not have received the update about ADR v3. If this is the case, I would kindly ask you to contact our support desk via a request in the portal.