On the possibility of sensing an early stage fire in moving vehicles by microwave radiometry

Microwave Radiometers for Fire Detection in Trains: Theory and Feasibility Study

“…A passenger train scenario is considered since it imposes the most severe constraints to the design of the radiometer hardware. According to [ 12 ], indeed, the radiometer is fixed and placed under a gate at a certain distance from the train. The instrument is able to scan the walls of each wagon, thanks to the train movement that happens at a known speed .…”

“…The latter is a very important instrument parameter similar to the exposition time of a common optical photo-camera. A quantitative description of this relationship can be found in [ 12 ]. From the qualitative point of view, however, it can be easily deduced that an increase of the train speed causes a reduction of the radiometer integration time and, as a consequence, a worse performance in terms of temperature resolution (this is discussed in Section 5 ).…”

“…From the qualitative point of view, however, it can be easily deduced that an increase of the train speed causes a reduction of the radiometer integration time and, as a consequence, a worse performance in terms of temperature resolution (this is discussed in Section 5 ). The main specifications of the microwave radiometer have been discussed in [ 12 ] and are summarized here in Table 1 .…”

“…The purpose of this research is to perform a feasibility study about the microwave fire detection in moving trains. A theoretical model of the scene sensed by a microwave radiometer has already been carried-out in a previous paper [ 12 ]. This model accounts for the presence of both fire spots and wall-like obstacles, while exploiting a rigorous definition of the filling factor.…”

“…From the study in [ 12 ] emerges the possibility of detecting fires in vehicles by using microwave sensors. The main assumption is that part of the vehicle body is made of non metallic materials or that the vehicle has dielectric walls or windows.…”