LoRa, developed by Semtech, refers to a technology dedicated to radio modulation and demodulation, which is a non-authorized band technology, which uses the current FM spread spectrum modulation technology, that is, the same as FSK (frequency shift keying) modulation Of the low power consumption characteristics, but also significantly increased the communication distance, while improving the network efficiency and eliminate the interference, that is, different expansion frequency sequence of the terminal, even if the same frequency at the same time to send will not interfere with each other, so on this basis Developed concentrator / gateway (concentrator / gateway), can receive and deal with multiple nodes in parallel data, greatly expanding the system capacity.