Abstract: To optimize the energy consumption and battery life of fire alarms using narrowband cellular IoT, we conducted an experimental analysis of the communication energy consumption characteristics of these devices. By establishing a test environment for evaluating the wireless communication reliability and low-power consumption patterns of fire alarms, we analyzed the coupling characteristics of typical operational states, communication, and power consumption of narrowband cellular IoT based fire alarms under different signal conditions. This analysis aimed to identify the operational states and common causes of power loss that critically affect energy consumption. The results showed that the heartbeat connection is the most critical factor affecting the energy consumption of narrowband cellular IoT based fire alarms. Additionally, as network signal quality deteriorates, the communication energy consumption of fire alarms significantly worsens, with peak current increases up to 350% and usage duration reduced to as low as 20.8% of the ideal state. Therefore, it is crucial to enhance the link attenuation resistance of narrowband IoT fire alarms during wireless networking, prevent excessively low signal quality, reasonably limit the frequency of heartbeat connections, and consider battery selection under poor signal coverage conditions.

Key words: independent fire detection and alarm, narrowband cellular IoT, communication energy consumption, signal quality