When WiFi doesn’t go far sufficient, and LoRa goes to interrupt the financial institution, there’s at all times the great world of ISM band radios! The SympleLink radio system from Raging Bits would possibly simply be what you’re in search of. In contrast to the tremendous low-cost ISM gadgets that ship a single UART stream, the SympleLink has firmware which might deal with a UART, an I2C bus, and four GPIO! That’s sufficient to regulate absolutely anything on the receiving finish.
Every gadget has a novel deal with, and can solely join and talk with its related central gadget. The gadgets are able to as much as a half of mile (800m) transmission distance if line-of-sight is feasible. A single Central module can talk with many Peripheral boards, and the included documentation is kind of detailed and could have you up and operating very quickly.
The SympleLink makes use of the LPD433 band, which implies that it’s solely authorized to make use of in Europe and Malaysia as an ISM band gadget; licensed beginner radio operators could possibly use these gadgets in the event that they adjust to all of the necessary laws (together with transmitting your callsign) nevertheless it’s finest to verify the legal guidelines in your nation.