For security reasons, I want to be able to monitor door status through quite a bit of concrete. I tried a couple of options from Skylink but they couldn’t quite make it. LoRa can send signals to satellites, so I think LoRa is the answer.
LoRa (from Long Range) is a low-power, low-bandwidth, long-range radio protocol. It’s meant to transmit infrequent status information over long distances in a battery-efficient manner. (Or this case, through a lot of intermediate material)
CubeCell makes a very low-power, Arduino/ESP32-ish board with built-in battery circuitry, and which in practice can reach the distance I need.
Important notes
- Various frequencies are permitted in various countries. For Canada it’s 902–928 MHz so if you’re buying hardware, make sure to get a model that supports that. (Normally it’s listed as a 866MHz version)
- Operating radio transmitters w/o an antenna can damage them – make sure antenna are connected before use.
Overall idea:
I haven’t found any turn-key projects for this, so my current idea is to use two CubeCells as a battery-powered remote stations. These would transmit status every ~20 hours, or on status change. A base CubeCell would receive this, and re-transmit the information via wifi. I happen to have a HomeAssistant setup with MQTT and VOIP support so that’s my goal, but email, SMS gateway, or other would obviously be easy to do at that point.