Abstract:

Aiming at the problem that the traditional fire alarm system cannot meet the actual fire alarm requirements in special occasions such as tall and narrow spaces, museums, cultural relics protection buildings, etc, designed a wireless fire alarm system based on LoRa and GPRS. The system used LoRa and GPRS separately for long- distance transmission of fire sensing information and fire alarm information. And Modbus communication is selected to connect LoRa and GPRS wireless module. The design process introduced the system control scheme, hardware composition and software design in detail, and carried out the system testing and experimental verification.The experimental results show that the system can monitor the field temperature and smoke data in real time, be able to alarm and send the information in time. The operation is stable, and the forecast is timely and accurate, which meets the needs of fire alarms on specific occasions. The application of the system can improve the ability of fire forecasting and enhance the emergency response capability of the fire, which is an effective supplement to the wired fire alarm system. 

Key words: LoRa, GPRS, fire alarm system, Modbus