I just got the Dragino LDDS75 LoRaWAN Distance Detection Sensor and connected it successully to TTN, configured the payload decoder and can receive the sensors readings in Cayenne.
What I want to achieve with the distance sensor is to monitor the amount of fluid level in a tank. What I get is a distance reading to the surface of the fluid. So I need to do some calculations:
($TANK_HEIGHT - $SENSOR_READING) x CONSTANT
to get the amount of fluid in the tank.
Where is the typical place to do such a thing? Should I modify the Payload Decoder or is there any other place to do this kind of stuff?
Thank you in advance!