LoRa and Meshtastic

Meshtastic is described as an off-grid text message project. The text messages travel entirely over a network consisting of LoRa devices connected in a mesh. What does “off-grid” mean in this context? It means the text messages use a network that has nothing to do with wifi or the Internet or cell phone service. Instead the messages are transported over a mesh network made up of multiple LoRa devices. The device that sends and displays the texts is a smartphone, connected by bluetooth to a LoRa device. The LoRa device is in turn part of a mesh network with other LoRa devices. Again, wifi, the Internet, or the cellular network are not involved. Bluetooth is used only to connect between the smartphone and the LoRa device. Thus the entire end-to-end text message is completed off the grid. Meshtastic is a firmware version that is installed on a LoRa device. One example of a LoRa device is a TTGO T-Beam, shown below. Meshtastic firmware has been installed.

What does LoRa and Meshtastic have to do with a remote station?

The answer to that question is, it can be used for station telemetry. That means temperature, voltage, and current can be texted back to the client automatically. The text messages can be generated by an Arduino microcontroller or a Raspberry Pi Pico microcomputer and fed into the Lora device. On the other hand the client can send texts that turn on relays or turn off relays. Equipment can be rebooted. Equipment can be turned on and off.

It is a plan to implement a Meshtastic system at the W0QL remote station once a Lora signal path is reliable.

Upon further study, it appears that the above scenario would work fine if the two endpoints were less than 2 miles a part. With distances of 35 miles it is not a solution. Meshtastic requires the mesh nodes, that is, the relays in the middle, to be under the control of the same operator as the end points. Given the t-beam units have a range of 2 miles, several nodes will be necessary as relays. The purchase cost, maintenance, and installation of multiple nodes may be a limiting factor to using Meshtastic. Moving on to similar technologies, would LoraWAN work?

Research on LoraWAN shows it needs a gateway to the Internet. Any gateway at the remote station site would be down if the Internet is down and therefore not usable at the very time it is needed most. Finding another gateway that is reachable out in the country is a challenge. Gateways require authorization and that’s where this technology is limited. So as of now there doesn’t seem to be a solution for telemetry monitoring over a 35-mile link that is within reason. Project is on hold.


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