You can use NRF24 module. https://howtomechatronics.com/tutorials/arduino/arduino-wireless-communication-nrf24l01-tutorial/
What is a distance between gateways?
You can use NRF24 module. https://howtomechatronics.com/tutorials/arduino/arduino-wireless-communication-nrf24l01-tutorial/
What is a distance between gateways?