LoRaWAN™ devices log data and transmit them regularly.
But if the message is not received by the network, the data is lost.
2 observations:
- The option to send x times the same radio message is available on any LoRaWAN ™ device, but it considerably reduce the battery life.
- 1 gateway can hardly acknowledge receipt of each message from several hundred products.
To remedy this problem, SENSING LABS offers 2 solutions with Senlab LoRaWAN™ sensors!
- Temporal redundancy
- You are able to define a redundancy coefficient R, which is the number of times a value. will be integrated into datalog message.
- The device still send 1 message at tx frequency with N new logs.
- The message will also embed previous values according to the redundancy coefficient
Example of redundancy use (with redundancy = x2):
TX1 = log 1 log 2 log 3
TX2 = log 1 log 2 log 3 log 4 log 5 log 6
TX3 = log 4 log 5 log 6 log 7 log 8 log 9 …
You can have up to 48 logs !
- Data recover
This mode allows to identify missed messages and will immediately send a downlink recover request.
Example of data recover use:
STEP 1 : you receive a payload with the 6 last logs (1-6)
STEP 2 : you send a downlink 0x02 0x00 (to ask for 6 logs before the last received logs )
STEP 3 : you receive a payload (start with 82) with 6 logs (7-12)
STEP 4 : you send a downlink 0x02 0x00 (to ask for 6 logs before the last received logs )
STEP 5 : you receive a payload (start with 82) with 6 logs (13-18) …
(The maximum number of logs to retrieve is 48 logs.)