What is the LoRaWan protocol
History and definition
LoRa is a low frequency radio network, created in 2009 by a French startup (Cycléo), and then acquired in 2012 by the American semiconductor company Semtech.
LoRaWAN (Long Range Wide-Area Network) is a communication protocol based on the LoRa network.
The goal of LoRaWAN is to enable the communication of information between low-power devices (such as battery-powered sensors) and software on local networks or in the cloud. In this energy-saving goal, LoRaWAN is specially designed to transmit small amounts of data with a low data rate. Example: measuring ambient temperature every 15 minutes.
One of the main features of the LoRa network is its extended range: it is a wireless network allowing communication up to several kilometers*.
* In areas crowded with large metallic obstacles or infrastructure, the range of the network is limited. However, it remains significantly greater than that of the most popular wireless network: Wi-Fi.
* In areas crowded with large metallic obstacles or infrastructure, the range of the network is limited. However, it remains significantly greater than that of the most popular wireless network: Wi-Fi.
The typical architecture of a LoRa network
To set up a LoRa network, two types of devices are necessary:
- Transmitters, often sensors (temperature, vibration, current, etc.).
- Receivers, commonly referred to as gateways.
The gateways are equipped with a LoRa radio antenna, which allows them to receive messages sent by the sensors.
Depending on your geographical area, the frequency bands used and authorized for the LoRa network are different:
Europe: 863 - 870 MHz / 433 MHz*
United States: 902 - 928 MHz
China: 470 - 510 MHz / 779 - 787 MHz
Australia: 915 - 928 MHz
India: 865 - 867 MHz
Asia: 433 MHz
North America: 915 MHz
* The 863 - 870 MHz bands will have a theoretical range greater than the 433 MHz band, but the latter will be more suitable for environments crowded with infrastructure and congestion.
Make sure you have compatible equipment according to the authorized frequency bands in your region.
The purpose of the gateway is to receive the messages sent by connected sensors, to decode these messages, and then to send the decoded data to the desired software or database.
LoRaWAN messages are sent in hexadecimal format. Sensor manufacturers provide technical documentation to transform this raw data into intelligible data.
For example: for a current sensor e-green Sensor from the brand TCT, the raw data received in LoRaWAN is: "a00808970b00060a1039". Once decoding is complete, the gateway returns the following data:
[
[
{
"payload":{
"d":{
"XXXXX":{
"Val":{
"XXXXX:temperature":21.99,
"XXXXX:current":0.06,
"XXXXX:voltage":4.153
}
}
},
"ts":"2024-12-31T10:56:56.063Z"
}
}
]
]
