Periodic Transmission With Redundancy - ADEUNIS LoRaWAN COMFORT CO2 Guide Utilisateur

LoRaWAN COMFORT CO2 - Guide utilisateur / User guide version V1.1.1

2.7.1 Periodic transmission with redundancy

The redundancy mechanism allows the user to add previous data in the current frame (see here under example). Thanks to this mechanism the
device keep a number of samples in its local memory to send them again in the new frame.
The associated parameters linked to this mode are:
• Sampling period (register 321), historisation frequency (register 320) and transmission frequency (register 301)
• The number of samples to be repeated in the next frame (register 323).
When redundancy is activated the frame will contain the number of bytes corresponding to the total of samples, that is S301+S323.
At the start-up of the device, the redundant signed bytes are completed by zeros until there is memorized samples.
Example with redundancy:
Register Encoding Value
value
S321 Decimal 1800
S320 Decimal 1
S301 Decimal 2
S323 Decimal 4
In this example:
• 1 sampling done every hour (1800x2seconds = 60 minutes)
• The historisation is made at each sampling
• The transmission is made every 2 savings (historisation) so every 2 hours
• The device will send a frame with 2 new samples and 4 memorized samples.
In this example, thanks to redundancy, if a frame is lost, the data is recovered in the 2 next frames.
Frame 1
Frame 2
Frame 3
Frame 4
Frame 5
Frame 6
Frame 7
New samples
Memorized samples
Result
1 sample every hour
(1800 x 2 seconds = 60 minutes)
1 historisation at each sampling
1 transmission every 2 savings
4 redundant samples per frame
Historisation/
Saving
Transmission
1h 2h 3h 4h 5h 6h 7h 8h 9h 10h 11h 12h 13h 14h 15h
FR
EN
Time
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