Feasibility Analysis of Potential Fire Monitoring Based on Reconfigurable Intelligent Surface Assisted (RIS-Assisted) Radiometers

Fire accidents in forest or urban areas can result in serious casualties and financial losses. Due to the penetrating ability of low-frequency microwave signals, the microwave radiometer is able to detect a potential fire hazard before the fire breaks out. Considering the flexibility and convenience in practical applications, the fire monitoring system based on microwave radiometers faces problems. To solve the problems, a novel reconfigurable intelligent surface-assisted (RIS-assisted) radiometer is proposed in this article. The trigger model (also called the system model) of RIS-assisted radiometers for early fire warning is derived. The system models of single and distributed RIS-assisted radiometers are derived and analyzed. The derivations of the system models also expound the operating principle of RIS-assisted radiometers for potential fire monitoring in practical applications. The numerical simulations and experiments are conducted, and the results validate the feasibility of the RIS-assisted radiometer for potential fire monitoring. Finally, to understand the RIS-assisted radiometer more comprehensively in practical applications, the imperfections of the experiment are discussed. By utilizing the technique of the RIS, the microwave radiometric system may have the opportunity to be applied to potential fire monitoring with low hardware complexity and low cost.