Check this article out, authored by my colleague, Bob Scannell. This is a great read, as it covers the state of technology that is evolving to address this important societal need.....
Bob summarizes this article in its opening lines:
"The precision location of first responders deep within GPS denied infrastructure has been an elusive goal of the fire safety and emergency personnel community for well over a decade. The objective is to pinpoint location to within a few meters, over the course of tens of minutes. These coincidentally are nearly the same goals as found in guidance systems on tactical missiles, for which the solutions of choice today can cost $10,000 minimum, and have prohibitive size, weight, and power. Those same solutions were used in early proof of concept demonstrators for first responders, but were proven to be barriers (cost and size) to actual deployment. First responder location determination, therefore, remains one of the most complex location applications in existence today. There is no one silver bullet sensor that can achieve the desired goals but multiple technology nodes are necessary, each of which are at the leading edge of capability. Furthermore, it involves a large scale sensor fusion and system integration approach. Cost-effective, high performance MEMS inertial sensors can now provide the seed for a potential solution. This article envisions a complete sensor-to-cloud sensor-fused system including highly sophisticated algorithm. "
