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Borewell water level monitoring using time slotted star network of LORA radios.
One of our customers needed to monitor the water level in multiple borewells spread over a large area with heavy vegetation and uneven terrain. They tried LoRAWAN over a period of 3-4 years but could not get it to work reliably.
WiSense has developed an economical wireless sensing and control solution which employs a time slotted star network of LORA radios with a low cost single channel LoRA + WiFi gateway at the center.
Since our gateway is low cost, multiple such star networks can replace a single expensive multi channel gateway with all the bells and whistles.
We have deployed 3 separate star networks for this customer, each receiving data from borewells in the vicinity.
We integrated our general purpose wireless sensor nodes with borewell sensors previously bought by the customer.
Borewell water level monitoring involves comparatively higher data traffic since changes in water levels due to pumping and subsequent natural in flow can all happen in a matter of minutes. It is important to capture these events. Our star network is time slotted to avoid collisions between different nodes sending data to the same parent gateway.
The time slotted star network has dedicated uplink and downlink slots for each sensor node allowing collision free bi-directional communication with each sensor node. This allows easy reconfiguration of sensor node behavior.
Max transmit power is +22 dBm. We could get up to 1.5 km range through dense vegetation.
The sensor nodes are all solar powered. We offer a solar li-ion charger power supply PCB which also includes a couple of V/I sensors to monitor solar and battery voltage/currents at all times.
Each data packet sent by a sensor node includes the following information:
- 64 bit IEEE assigned globally unique id/address
- Borewell water level in mm
- Li-Ion battery voltage in mV.
- Li-Ion battery current in mA (negative value when discharging, positive value when charging)
- Solar panel voltage in mV.
- Solar panel current in mA
- A 32 bit message sequence number
- Data transmission interval in seconds
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One of the gateways mounted on top of a tall pole
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Snapshot of borewell water level chart taken from sensor dashboard hosted on AWS
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Snapshot of a specific borewell sensor node’s dashboard hosted on AWS
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